Rice, a staple food for more than half of the world’s population, is grown in >100 countries with 90% of the total global production from Asia. Although there are more than 110,000 cultivated varieties of rice that vary in quality and nutritional content, after post-harvest processing, rice can be categorized as either white or brown. Regional and cultural preferences as well as need for stability during storage and transport are the final determinants of market availability and final consumption. In addition to calories, rice is a good source of magnesium, phosphorus, manganese, selenium, iron, folic acid, thiamin and niacin; but it is low in fiber and fat. Although brown rice is promoted as being “healthier” because of bioactive compounds, including minerals and vitamins not present in white rice after polishing, white rice is more widely consumed than brown. This is for several reasons, including cooking ease, palatability, and shelf life. Polished rice has a higher glycemic load and may impact glucose homeostasis but when combined with other foods, it can be considered part of a “healthy” plate. With the projected increase in the global population, rice will remain a staple. However, it will be important to encourage intake of the whole grain (brown rice) and to identify ways to harness the phytonutrients that are lost during milling. Furthermore, as the world faces environmental challenges, changing demographics and consumer demands, farmers, healthcare providers, food manufacturers and nutritionists must work collaboratively to assure adequate supply, nutritional integrity and sustainability of rice production systems globally.

New evidence shows that the number of hungry people in the world is growing, reaching more than 820 million in 2018 (one in every nine people), up from 812 million in 2017. There are three main causes of food insecurity: high exposure and vulnerability to climate extremes, conflicts, and economic slowdown. Paradoxically, every year, roughly one third of the food produced in the world for human consumption—approximately 1.3 billion tonnes—is lost or wasted. It is estimated that, if the food lost or wasted globally could be reduced by just one quarter, this would be sufficient to feed the people suffering from chronic hunger in the world. Rice, an important staple food for over half the world’s population, is also affected. At the same time, evidence shows that the food lost or wasted is a major cause of greenhouse gas emission, which itself feeds into climate change and extreme weather, resulting in further food insecurity and malnutrition. This paper briefly introduces the Food and Agriculture Organization of the United Nations (FAO), presents the recent findings on the current situation of food security and nutrition in the world, and highlights the issue of food loss and waste and its impact on food security, with particular emphasis on the constraints it poses to the achievement of key Sustainable Development Goals (SDGs).

Rice (Oryza sativa) is one of the most important food crops in the world, and the effect of its consumption on human health is of great concern. Evidence has accumulated that rice contains several components, such as γ-oryzanol and rice bran fibers, which modulate the immune system. In addition, rice has other immunologically beneficial characteristics. It has a low allergenic potential and is gluten-free, reducing the risk of development of food allergies and diseases related to gluten sensitivity such as coeliac disease. This review presents the recent advances in our understanding of the immunomodulatory function of rice components.

Hunger and malnutrition, especially children, are still global issues today. Rice is a staple food for more than half of the world population and important nutritional source of not only carbohydrate but also protein. In recent aging societies, protein-energy malnutrition in elderly people emerges also as a social issue. Malnutrition in elderly people raises the risk of falling into age-related chronic diseases. Nutritional care can prevent elderly people from such age-related diseases. Rice and rice flour would be good foodstuff for preparation of diet suitable for and preferred by elderly people. Protein content of rice grains, like the other cereal grains, is less than 10% by weight, which is a little lower than meat and cheese, but higher than dairy milk and yoghurt. Nutritional quality of rice proteins is higher than the other cereal grains. Such relatively higher nutritional quality of rice proteins could be due to high copies of glutelin genes evolved from an ancestral gene common to soybean glycinin and resultant high content of legume-type seed storage proteins. Recently, rice flour became to be utilized for various processed food. The rice seed proteins as well as starch are accumulated in specific organelles termed protein bodies and amyloplast in the cells of endosperm and aleurone layer. By milling rice grains to flour particles consisting of protein and starch nanoparticles, processing characteristics of rice starch and proteins could be changed. To develop rice-based processed food for prevention of malnutrition, rice flour particles from various different rice sources could be blended for desired nutritional composition without spoiling the value of product food.

Inositol hexaphosphate (IP₆) and its parent compound myo-inositol (Ins) are active compounds from rice and other grains, with a broad spectrum of biological activities important in health and diseases. However, the most striking is the anticancer effect of IP₆ and Ins that has been actively investigated during the last decades. A consistent and reproducible anticancer action of IP₆ has been demonstrated in various experimental models. IP₆ reduces cell proliferation, induces apoptosis and differentiation of malignant cells via PI3K, MAPK, PKC, AP-1 and NF-kappaB. Very few clinical studies in humans and case reports have indicated that IP₆ is able to enhance the anticancer effect of conventional chemotherapy, control cancer metastases, and improve quality of life. Reduced burden of chemotherapy side-effects in patients receiving IP₆ alone or in combination with Ins has been reported. Because of the highly promising preclinical and emerging clinical data, large clinical trials and further mechanistic studies are warranted.

Production technology for rice in the world has been advancing. The supply curve has shifted to the rightward and become flatter over time as well as the scale of economies have been enlarged in many countries. This has led to a great increase in yield per ha. and greater production globally. Accordingly, the rice prices have been becoming more stable and cheaper over time in real term despite of price hike around 2010. Potential of rice production increases for the future is quite large, while demand for table rice has been somewhat stagnant in major producing countries. Because the technology advancement is overwhelming in all food production, it would be hard to expect a global food shortage in the future, unless man sabotages. Developments of new products using rice for functional food may be important for the rice industries, therefore. Meanwhile, in the global rice economies, japonica rice markets are becoming phenomenal in high demand relative to indica. This may be possibly due to a globally long-lasting booming of Japanese restaurants featured by Sushi. Demand for japonica rice has been so strong that the prices of japonica rices are about double of indica rice. Because of short in supply relative to demand for japonica rice marketed globally, there are emerging japonica rice production in many rice producing countries shifting from indica rice to japonica, although the japonica rice production in each new area is still small.

As a staple food crop rice caters to the energy needs of more than 4 billion people around the globe. Since the 1980s, rice breeding focused on breeding for superior grain quality with good texture, taste, palatability and aroma. The recent rise in double burden nutrition challenges suggests that there is a pressing need to focus on incorporating nutritional traits also in rice breeding efforts. The present rice based diet contains nutritional gaps mainly due to the milling process which removes health promoting compounds present in rice bran. Therefore, less milled or brown rice consumption is highly recommended to achieve nutrition sustainability. Brown rice contains relatively higher amounts of dietary fibre, moderate amount of proteins, unsaturated lipids, micronutrients and several bioactive compounds. Some landraces consumed as brown rice have low glycemic index properties; hence they might be helpful to counter the growing type II diabetes. Colored rice varieties with red or purple pericarps are known to possess high levels of bioactive compounds such as cyanidin-3-glucoside, various flavanoids and γ-oryzanol. Germinated brown rice has more potential health benefits, for example, 10-fold of γ-aminobutyric acid than milled rice. For future nutritional intervention, we recommend further explorations into the nutritional value of brown rice as well as to modify the endosperm for enhanced nutrition without altering the texture to ensure consumer acceptance.

Japan achieved remarkable economic development after World War II, which has led remarkable changes in risk factors of atherosclerotic diseases and led to epidemiological transition in Japan. Nowadays, obesity is pandemic around world, which is same case in Japan. BMI of Japanese population, especially young adult men increased gradually since the 1960s associated with increase in intake of fat as well as decrease in intake of rice, which has been revealed by the annual report of the Ministry of Health, Labour and Welfare. Such changes suggest the change of dietary habit from Japanese style to westernized style. In recent years such changes in lifestyle has been accompanied by a gradual increase in serum cholesterol in the Japanese population, which is associated with increase in the incidence of cardiovascular diseases (CVD). Japanese guidelines recommend “The Japan diet” to prevent CVD, because there are several epidemiological data to show the cardio-preventive effect of fish, soy bean, and vegetables, which are the major component of “The Japan Diet”. It is very important to recognize the diet habit is one of culture and that rice plays a pivotal role in “The Japan Diet”.

The dietary fat intake of Japanese is thought to be more appropriate than in Western countries; however there is a range of differences of individuals in the amounts of fat intake and n-6/n-3 ratio. Therefore, it is important what kind of vegetable oils are used for cooking in order to consider the total balance of fat intake. Rice bran oil (RBO) is expected to reduce plasma cholesterol and be useful for prevention of cardiovascular disease because it contains several effective ingredients. RBO is rich in linoleic and oleic acid. RBO contains γ-oryzanol, which is well known to reduce plasma cholesterol levels. Furthermore, it contains tocotrienols, which are analogs of vitamin E, reported to have unique bioactivity different from that of α-tocopherol. The biological function of these components and their potential to prevent Japanese lifestyle-related diseases are discussed.

Inspite that rice is a main staple and heaviliy consumed in most of Asian populations, health effect of rice has been less examined in nutritional epidemiologic studies compared to those of foods such as fruits, vegetables, meats and fish. Some recent meta-analyses that collected prospective cohort studies reported the associations between rice intake and incidence of and mortality from some chronic diseases especially type 2 diabetes. Concerning type 2 diabetes, the results are remarkably different between white (polished) rice and brown (unpolished) rice: the former increased and the latter decreased the risk. This difference may partly be explained by the different types and amounts of dietary fiber and different scores of dietary glycemic index. However, the results on dietary fiber and dietary glycemic index were not necessarily consistent. Indirect effect of rice intake has been examined through the studies on association of dietary patterns and breakfast skipping to type 2 diabetes. However, most of the results were inconclusive. Simple and straightforward judgement on the effect of rice to type 2 diabete should be avoided, and more nutritional epidemiologic studies with high research quality, including basic studies on dietary assessment, are needed, especially in Asian populations.

Although it is considered a staple food, rice intake is under serious debate for its physiological usefulness, especially for diabetic patients, because of starch content. However, rice protein, the second major component of rice, has gained attention recently for its newly-discovered functions, which were previously unknown. Rice protein, a plant protein, shows multiple beneficial functions on lipid metabolism and diabetes and its complications, nephropathy, fatty liver and osteoporosis. Rice proteins of endosperm and bran, an ingredient of white rice and an unused product of brown rice, respectively, are valuable components for human health.

Soft textured rice is the major source of calories in the diet of most South East (SE) Asian countries. However, it is most often consumed after polishing which removes the bran and embryo and hence most of the vitamins, minerals and dietary fibre (DF) are lost. Consequently, white rice comprises over 90% starch with only trace amounts of DF and is rapidly digested in the human gastrointestinal tract, resulting in a high glycaemic index (GI). The excessive consumption of high GI foods is associated with increased risks of a range of chronic diseases including type-2 diabetes, cardiovascular disease (CVD) and some types of cancer. Furthermore, the incidence of these conditions is dramatically increasing in areas where white rice is the staple food, notably Asia, with the prevalence of diabetes in SE Asia alone predicted to reach 120 million by 2030. It is therefore necessary to develop rice lines in which high energy content is combined with low GI. This may be achieved by combining acceptable levels of resistant starch (RS) with an increased content of the cell wall derived-dietary fibre components.

Parkinson’s disease (PD) is a common progressive neurodegenerative disease. It has been reported that oxidative stress contributes, at least in part, to its pathogenesis. Although dietary epidemiological studies suggest that sufficient intake of vitamin E may prevent the onset of PD, antioxidative therapy for PD with exogenous antioxidants involving α-tocopherol has not been successful in the clinical setting thus far. In recent years, the non-antioxidant activities of vitamin E have been given attention to. In the present study, to determine the antioxidant-independent cytoprotective activity of vitamin E, we investigated whether tocotrienols (T3s), another members of vitamin E family, exhibit the neuroprotective effect in cell and mouse models of PD independently of their antioxidant activities. Treatment with T3s, especially γ- and δ-T3s, exhibited cytoprotective effects via activation of PI3K/Akt signaling pathway in a cellular PD model. We also identified estrogen receptor (ER) β as an upstream mediator of PI3K/Akt signaling and demonstrated the direct binding of T3 to ERβ in vitro. Silencing expression of caveolin suppressed the cytoprotective effects of T3, indicating that caveola formation plays an important role in the cytoprotection by T3 via ERβ/PI3K/Akt signaling pathway. Thus it has been shown that T3 exerts cytoprotective function by a novel mechanism, which includes membrane ERβ/PI3K/Akt signaling via caveola formation as well as its antioxidant activity. Furthermore, we revealed that δ-T3 treatment relieved PD-related symptoms in PD model mice. These results suggest that T3 elicits the cytoprotective effects via ERβ/PI3K/Akt signaling pathway in cellular and murine PD models.

In this research the incapsulation of ferulic acid (FA) in advanced systems of protection with the aim of improving its stability and photostability was studied. Lipoparticles and polymeric microparticles as incapsulation systems were prepared and characterized. Lipoparticles were completely of natural origin, while microparticles were obtained using chitosan as natural polymer. In both systems FA stability was greatly increased and its organoleptic properties in the emulsions did not change.

Gestational Diabetes Mellitus (GDM) is one of the most frequent complications of pregnancy and is characterized by a carbohydrate intolerance which is diagnosed with the oral glucose tolerance test. The prevalence of GDM in our population is about 12%, but risk factors like a previous GDM, ethnicity, a parent with diabetes mellitus type 2 and maternal overweight may increase its occurrence. Complications of GDM are a pre-term birth (before 37 wk gestation), macrosomia (birth weight ≥4 kg) and gestational hypertension. Actually, GDM is principally treated with diet and, if it is necessary, with insulin; but the challenge is the prevention of GDM. Among the measures used, changes in life-style (diet+exercise) failed to prevent GDM whereas metformin showed conflicting results. A promising supplement is myo-inositol (MI) which was given from first trimester until delivery to women at risk for GDM reporting a significant decrease in GDM occurrence by more than 60% comparing to the placebo group. Recently, a secondary analysis from 3 randomized controlled trials demonstrated that MI may also significantly reduce some of GDM complications such as pre-term birth and macrosomia with a favorable impact on mother and fetus well being.

As an intermediate metabolite during the biosynthesis of sterols, squalene is found ubiquitously in plants and animals. In rice, squalene is contained in rice bran, and consequently, squalene in rice bran oil has gained attention. Studies have shown that the intake of squalene from food sources demonstrate various physiological benefits such as the prevention of cancer and cardiovascular disease. Squalene is also known as an effective antioxidant in edible oils. However, due to its chemical structure, squalene is susceptible to oxidation, which may cause a decline in the nutraceutical and antioxidative effects of squalene in edible oils. Oxidative degradation of squalene also results in the formation of scission products (i.e., aldehydes and ketones) which may lead to off-flavor. Since the rate of squalene oxidation depends on the factors that induce its oxidation (i.e., light or heat), emphasis on oxidation mechanisms is necessary. It has been demonstrated in previous studies that the oxidation products formed by the singlet oxygen oxidation and free radical oxidation of squalene are different, and more recently, we demonstrated that different squalene monohydroperoxide isomers are formed by each oxidation mechanism. We herein discuss the significance of squalene in rice bran oil as well as the oxidative degradation of squalene in edible oils with focus on oxidation mechanisms.

Low-carbohydrate, high-protein diets, known as carbohydrate-restricted diets, are in contrast to the carbohydrate-centric meals typical of the Japanese diet. Carbohydrate-restricted diets were reported to reduce visceral fat, owing to which they have attracted attention and been widely implemented. If, as proposed, carbohydrate-restricted diets are effective in delaying senescence, then Japanese diets have a hidden potential to evolve further. However, long-term carbohydrate restriction in mice was reported to have a negative effect on the cardiovascular system, with shortening of lifespan due to activation of mechanistic target of rapamycin (mTOR). As a result, the safety of long-term adherence to carbohydrate-restricted diets remains doubtful. Recently, we conducted a study using senescence-accelerated mouse-prone 8 (SAMP8) mice to examine the effects of a carbohydrate-restricted diet on aging and skin senescence, and to determine the effect of long-term carbohydrate restriction on the aging process in mice. Here, we discuss the safety of long-term carbohydrate restriction based on the findings obtained from animal studies.

γ-Oryzanol contained as a minor component in rice bran oil (RBO) is a group of phytosterol ferulates. The existence of γ-oryzanol in rice bran oil is very interesting because of the special biological functions. The methods to determine γ-oryzanol in crude RBO include the absorptiometry, thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). However, those methods need much solvent and long operating time. Moreover, some of those methods are not able to apply to refined RBO because of the low sensitivity. We have developed the method to determine γ-oryzanol in refined RBO using proton nuclear magnetic resonance (¹H-NMR). Refined RBO had a specific chemical shift due to the methoxy group of ferulate in γ-oryzanol at 3.9 ppm on the ¹H-NMR spectrum. The intensity of the chemical shift due to the methoxy group of ferulate was consistent with the amounts of γ-oryzanol in refined RBO. This NMR method was able to quickly and easily determine γ-oryzanol in refined RBO.

For Thai people, rice is not only regarded as a staple food but a sacred plant with a spirit, a life and a soul of its own. Many exquisite cultural traditions and customs associated with rice and Thai people are usually performed nationwide from sowing to harvesting such as the Royal Ploughing Ceremony, Morale Blessing Ceremony to Phosop. During the 2007-2016 period, while the planted area (72,217,000 rai), harvested area (68,332,000 rai), production (32,874,000 ton) and yield (480 kg/rai) varied slightly, the price (10,232 Baht/ton) and value (337,849 million Baht) at farm gate steadily decreased. To raise the farmers’ income, rice strategy must be changed to create higher value from exports of rice-based products by using innovation instead of exporting a high volume of commodity-grade traded at a low price. Various kinds of value-added healthy processed rice-based foods are accessible in the markets as well as food supplements, food ingredients, cosmetics and medicinal products. In Thailand, rice is mainly consumed as normal cooked rice or glutinous rice and processed into flour, noodle, alcoholic drink, snacks, baked foods, desserts and beverages. Recently, organic rice, pigmented rice and low glycemic index rice with higher price and nutritive value have been available as an alternative choice for health conscious consumers and people with non-communicable disease. Innovative and functional products from that premium rice have been widely encouraged. This will help to support Thai rice farmers and help in strengthening and leading to sustainable Thai economy.

Brown rice contains many ingredients that might protect against cognitive decline and Alzheimer’s disease. However, brown rice is very hard, difficult to cook, and is poorly digested; thus, it is difficult to eat long-term. To solve these problems, ultra-high hydrostatic pressurizing brown rice (UHHPBR) was prepared. We investigated the effects of dietary UHHPBR administration for 24 mo on cognitive function and mental health in the elderly. Healthy elderly participants (n=52) were randomized into UHHPBR and polished white rice (WR) groups. The UHHPBR group consumed 100 g of UHHPBR per day for 24 mo and the WR group consumed white rice. At baseline, and after 12 and 24 mo, cognitive functions were assessed using the Revised Hasegawa’s Dementia Scale, Mini-Mental State Examination, Frontal Assessment Battery (FAB), and the Cognitive Assessment for Dementia, iPad version (CADi). Mental health condition was also assessed using the Apathy Scale and the Zung Self-Rating Depression Scale, and serum biochemical parameters were determined. From baseline to month 24, the mean change in the FAB-sub item 1 scores was higher in the UHHPBR group compared to the WR group. Furthermore, apathy scores decreased, as well as the time required to answer all questions of the CADi, and plasma epinephrine levels increased. These results indicate that a 2-y oral consumption of UHHPBR increases information processing speed (as a measure of cognitive function) and improves apathy in the elderly, suggesting a protective effect of UHHPBR administration against age-related decline in brain cognition and motivation.

Bone embrittlement with aging, namely osteoporosis, is characterized by low bone mass and deterioration of bone tissue, and can lead to increased risk of fracture. The development of functional foods that can prevent geriatric diseases is in progress. Our focus was on brown rice because of its properties. An interventional study using of ultra-high hydrostatic pressurized brown rice (UHHPBR) for human has not yet been conducted. In this study, we investigated whether long-term dietary intake of UHHPBR prevents aging-related decline of bone mineral density in elderly Japanese individuals. Elderly participants (n=40; mean 73.1 y) in Iinan-cho, Shimane, Japan, were randomly divided into two groups. The UHHPBR-intake group (n=20) consumed 100 g of UHHPBR and 100 g of white rice (WR) per day for 12 mo, while the WR-intake group (n=20) consumed 200 g of WR per day. Pre- and 12-mo post-intervention, bone mineral density was evaluated by quantitative ultrasound. After 12 mo of intervention, the UHHPBR group’s bone mineral density was significantly higher than the WR group’s bone mineral density. Moreover, chronic intake of UHHPBR had no adverse side effects on participants. Long-term oral UHHPBR intake may have beneficial effects on bone mineral density decline and may attenuate osteoporosis in the elderly.

Pregerminated brown rice (GBR) is assumed to be more beneficial than polished white rice (WR), with regard to nutrition and cardiovascular health. To support this with scientific evidence, cholesterol-lowering and antioxidative effects of GBR were studied in the present investigation. The most popular rice variety in Bangladesh BIRI-29 was used to prepare GBR and WR. Initially, we analyzed the proximate composition, antioxidative phytochemicals, in vitro 2, 2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging ability and anti-hemolytic effects of GBR. To examine the dietary impact and possible benefits of the GBR, experimentally-induced hypercholesterolemic (HC, 1% cholesterol) rats were fed with GBR against WR for 12 wk. At the end, plasma total cholesterol (TC), low- and high-density lipoprotein-cholesterol (LDL-C and HDL-C), triglyceride (TG), fecal TC, and hepatic TC, lipid peroxide (LPO) and proinflammatory TNFα levels were determined. Relative to WR, GBR contained higher amounts of total polyphenols, total flavonoids, β-carotene and lycopene, and exhibited a stronger in vitro DPPH-free radical scavenging ability and antihemolytic potentials. Levels of plasma TC, LDL-C, TG, and hepatic TC and TG significantly decreased, while plasma HDL-C and fecal TC levels significantly increased in the GBR-fed HC-rats, indicating dietary GBR demonstrates a stronger antilipidemic effect than WR. The hepatic levels of LPO and TNFα also decreased (p<0.05) to a greater extent in GBR-fed HC-rats than those in the WR-fed rats. It is thus concluded that dietary GBR could be a natural treatment of hypercholesterolemia and related cardiovascular risk factors, and a source of antioxidants to reduce hemolysis and related anemia.

Tricin present in rice and wheat exhibits antigrowth activity in several human cancer cell lines and anti-inflammatory potential. However, the chemopreventive activity has not yet been elucidated in preclinical animal models. This study was designed to determine whether dietary tricin exerts inflammation-associated colon carcinogenesis induced by azoxymethane (AOM) and dextran sulfate sodium (DSS) in mice. Male Crj: CD-1 mice were initiated with a single i.p. injection of AOM (10 mg/kg bw) and followed by a 1-week exposure to DSS (1.5%, w/v) in drinking water to induce colonic neoplasms. They were then given the experimental diet containing 50 or 250 ppm tricin. The experiment was terminated at week 18 to determine the chemopreventive efficacy of tricin. The effects of dietary tricin on the expression of several inflammatory cytokines, including tumor necrosis factor (TNF)-α, were also assayed. Feeding with tricin at both doses significantly inhibited the development of colonic tumors. Dietary tricin also significantly reduced the proliferation index and the numbers of mitoses/anaphase bridging of adenocarcinoma cells. Tricin feeding significantly suppressed the TNF-α expression in the normal appearing crypts. Our findings may suggest a potential use of tricin for clinical trials of colorectal cancer chemoprevention in the inflamed colon.

α-Tocopheryl succinate (TS) is a succinic acid ester of a well-known natural antioxidant α-tocopherol (α-T). Physicochemical characteristics of TS are entirely different from the original compound α-T. TS becomes vesicles via forming a lamella structure. Furthermore, although the antioxidative activity of α-T is lacked by esterification of phenolic hydroxyl (OH) moiety with succinate, TS has versatile biological functions, such as inhibition of cholinesterase activity, inhibition of nuclear factor-kappa B (NF-κB) activation, enhancement of lipopolysaccharide-induced nitric oxide production, and anticancer effect. Especially, we expect TS as a novel anticancer agent. TS nanovesicle shows significant anticancer activity in vitro and in vivo. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase produces superoxide which mediates the anticancer activity of TS. Moreover, it suggests that TS activates protein kinase C via direct interaction. Based on the analysis of structure and activity relationship, it ensures that succinate moiety of TS plays a vital role in anticancer activity. This review introduces the detail and mechanism of versatile biological functions of TS.

Astaxanthin (Asx) is known to be a potent quencher of singlet oxygen and an efficient scavenger of superoxide anion. However, the scavenging activity of Asx toward the hydroxyl radical was currently unclear because the high lipophilicity of Asx prevents analysis of such activity in water. Liposomes containing Asx (Asx-lipo) were previously shown to be dispersed in water. Analysis of the hydroxyl radical scavenging activity of Asx-lipo demonstrated a dose-dependence in water, with the effect of Asx being more potent than the vitamin E α-tocopherol (α-T). Furthermore, liposomes co-encapsulating Asx and vitamin E derivatives, namely tocotrienols (T3), showed a synergistic elimination effect on singlet oxygen and hydroxyl radical, although the antioxidative activity of liposomes co-encapsulating Asx and α-T was lower than the calculated additive value of each independent activity. A calculation of the most stable structure of Asx in the presence of α-T or T3, suggested that only T3 was able to hydrogen bond with Asx, and the Asx polyene chain partially interacting with the α-T3 triene chain, which could explain the synergistic effect between Asx and T3, but not Asx and α-T. This review introduces the hydroxyl radical scavenging activity of Asx, and its synergistic effect with T3.

Diabetes mellitus (DM) greatly impacts human health worldwide as over 400 million patients suffer from DM-related symptoms. Type 2 DM accounts for more than 90% of DM and is caused mainly by unhealthy lifestyles, such as high-calorie and high-fat diets. Such undesirable eating habitats induce resistance to insulin resulting in high blood sugar levels that cause induction of various symptoms and complications of DM. Therefore, management of blood sugar levels is important for preventing DM. Our group has recently found that rice (Oryza sativa L.) contains anti-diabetes compounds. Here, we summarize the effect of the bioactive ingredients in rice on preventing type 2 DM.

This study evaluated the postprandial glycemic response and physical properties of the high-amylose rice, Koshinokaori (KK), cooked under different conditions. Twelve healthy subjects (Japanese, 6 males, 6 females) were given cooked, white KK rice or tomato chicken rice (TCR) using KK rice. The Japanese standard rice, Koshihikari (KH), was used as reference. All meals contained the same amount (50 g) of available carbohydrate. Blood glucose levels were measured at 0 (fasting), 15, 30, 45, 60, 90, and 120 min after each meal. The results from the cooked, white KK rice showed a significant difference in blood glucose variation at 60, 90, and 120 min and the incremental area under the curve (IAUC) of blood glucose concentration for KK cooked at optimal water to rice ratio was observed. Blood glucose variation and IAUC after intake of TCR-KK rice was lower than that after TCR-KH rice intake. Addition of 5% trehalose to KK rice resulted in a smaller decrease in adhesiveness and stickiness of cooked rice after 180 min at 20ºC. The addition of 5% trehalose to KK rice also produced favorable results in the sensory evaluation. KK rice produces favourable postprandial glycemic responses and physical properties under varied cooking condition and thus, may be beneficial in the prevention of lifestyle-related diseases such as type 2 diabetes.

Dewaxed brown rice (DBR), which is prepared by removing only the outermost wax layer of brown rice using a new rice milling technique, has improved water absorbency, digestibility, and taste compared to regular brown rice. DBR has a nutritional value close to that of brown rice, including a rich amount of lipopolysaccharides that are known to improve cognitive function in mice. This study thus aimed to verify the influence of continuous DBR ingestion on cognitive function among elderly individuals. The present study employed a crossover comparison design using the Revised Hasegawa Dementia Scale to assess cognitive function. Our findings confirmed that long-term DBR ingestion contributed to the prevention and reduction of overall cognitive decline, especially among elderly individuals with low cognitive function. Thus, DBR has the potential to be a useful staple food that maintains brain homeostasis among elderly individuals.

A total of 101 local rice varieties, composted of 85 glutinous and 16 non-glutinous varieties grown in wet season 2016, were analyzed for tocopherols (TOC), tocotrienols (T3) and γ-oryzanol (Orz). Two popular varieties, RD6 and KDML105, were used as standard checks for glutinous and non-glutinous varieties, respectively. γ-TOC was found in all glutinous varieties (0.47-9.78 mg/kg), which were higher than RD6 (0.16 mg/kg). α-TOC was found in 40 varieties (1.02-6.29 mg/kg), only 6 varities were higher than RD6 (3.95 mg/kg). δ-T3 was found in 81 varieties (0.57-7.00 mg/kg), mostly varities were higher than RD6 (0.67 mg/kg). γ-T3 was found in all glutinous varieties (8.00-22.1 mg/kg), while RD6 contained 13.3 mg/kg. For α-T3, it was found in 39 glutinous varieties (1.52-9.94 mg/kg), mostly varities were higher than RD6 (2.62 mg/kg). Orz was found in all glutinous rice varieties (276-638 mg/kg), while RD6 contained 423 mg/kg. γ-TOC was found in all non-glutinous varieties (0.67-5.21 mg/kg), which were higher than KDML105. α-TOC was found in only 5 varieties (1.92-2.83 mg/kg), while KDML105 contained 2.23 mg/kg. δ-T3 was found in all non-glutinous varieties (1.64-8.87 mg/kg), which were higher than KDML105 (0.71 mg/kg). γ-T3 was also found in all non-glutinous varieties (8.80-17.58 mg/kg), while KDML105 contained 15.8 mg/kg. α-T3 was found in 9 non-glutinous varieties (4.56-8.93 mg/kg),while KDML105 contained only 0.86 mg/kg. Orz was also found in all those non-glutinous varieties (272-469 mg/kg), while KDML105 contained 469 mg/kg. These results indicate that γ-T3 was the highest vitamin E isomer present in all rice samples, while γ-TOC, α-TOC, δ-T3 and α-T3 were present in trace amounts. Orz was found in all local rice varieties.

Dehydrin proteins, group2 LEA proteins in rice bran and soybean whey were analyzed by two-dimensional (2D) electrophoresis, and the cryoprotective activity on freeze/thaw inactivation of lactate dehydrogenase was examined as a criterion of its function. Dehydrins in rice bran were detected by immunoblotting using antibody raised against a conserved lysine-rich motif sequence. In the water-soluble fraction of rice bran, 10 spots of 44 kDa and 23 kDa dehydrin-like polypeptides were detected on the immunoblotted membrane. Isoelectric points of the polypeptides were between 6.6 and 7.4. The 23 kDa dehydrin polypeptide was partially purified by ammonium sulfate fractionation and ion exchange column chromatography. CP₅₀ value, protein amount necessary to keep 50% of enzyme activity, of the 23 kDa dehydrin was 0.78 μM (15.6 μg/mL), slightly lower than that of bovine serum albumin. Heat-soluble soybean whey proteins were analyzed by SDS-PAGE and 2D-electrophoresis. Dehydrin appeared to be the most abundant protein in the fraction. CP₅₀ value for heat-soluble whey protein was estimated to be 15.8 μg/mL, while that of total whey was 355 μg/mL. The result indicated that simple heat fractionation is efficient to concentrate cryoprotective protein from soybean whey.

Starch starts to retrograde and form a crystalline structure immediately after gelatinization upon heating with water. The retrogradation rate is affected by the starch granule size, degree of polymerization, amylose/amylopectin ratio, starch concentration, water content, and storage temperature. Retrogradation of amylose occurs over a short term, while that of amylopectin occurs over a long term. The degree of starch gelatinization and retrogradation is evaluated by the degree of crystalline structure formation, viscoelastic properties, molecular mobility, and enzymatic digestibility using thermal, rheological, spectroscopic, and chemical techniques. The addition of carbohydrates, lipids, proteins, salts, acids, polyols, and enzymes changes the starch retrogradation rate, and some of these prevent retrogradation.

scyllo-Inositol (SI) is one of the inositol stereoisomers, rare in the nature, and expected as a promising disease-modifying therapeutic agent for Alzheimer’s disease. On the other hand, myo-inositol (MI) is another inositol stereoisomer most abundant in nature and thus supplied from agricultural byproducts including rice bran. Bacillus subtilis was genetically modified in its inositol metabolism and phytase secretion, to develope the bioconversion processes to produce SI from rice bran. Phytase, an enzyme that degrades phytate in rice bran into MI, was secreted in a B. subtilis strain with the optimized signal peptide. Another B. subtilis strain was constructed with the constitutive and simultaneous overexpression of IolG and IolW, which are the two inositol dehydrogenases responsible for the conversion, to demonstrate an efficient conversion of MI into SI with a rate up to 10 g/L/48 h. In order to devise further elevation in the conversion efficiency, we attempted to improve the substrate uptake by overexpressing iolT for the major MI transporter. In addition, Escherichia coli pntAB encoding the membrane-bound transhydrogenase was introduced aiming at enhanced supply of NADPH required for the rate-limiting IolW reaction. These additional modifications successfully elevated the conversion efficiency with an improved rate up to almost 30 g/L/48 h. Together with the improved phytase secretion, technological infrastructure for social implementation of SI production from rice bran is on the way.

Rice are consumed mainly as polished rice grains. In the threshing and polishing processes of paddy rice, a considerable amount of husk and bran are separated as by-products. Rice bran is utilized for oil production, whereas rice husk as well as straw is not fully utilized. Defatted rice bran is rich in proteins and non-digestible polysaccharides, while husk and straw consist mainly of plant cell wall components, including cellulose, hemicellulose and pectin. Such non-digestible polysaccharides function in gastrointestinal lumen as dietary fiber, though physiological functions and their application are limited. Non-digestible oligosaccharides have recently been interested as prebiotics from a viewpoint of health benefit via utilization by intestinal microbiota. A diversity of non-digestible polysaccharides in rice bran and husk are good and ecological sources for production of both prebiotic and potentially prebiotic oligosaccharides. In this review, we summarize non-digestible polysaccharides constituting cell wall of rice grains including husk and degradation of the polysaccharides into oligo- and monosaccharides by microbial glycoside hydrolases. Prebiotic potential of such oligosaccharides derived from rice non-digestible polysaccharides are also introduced. Finally, our recent attempt for effective production of cello-oligosaccharides by regulated enzymatic degradation is briefly described.

Dietary therapy through a low-protein diet (LPD) has long been used for preserving the renal function of patients with chronic kidney disease (CKD). Reducing the amount of protein ingested from rice would make it possible to allocate the difference to side dishes, thereby improving the quality of meals and facilitating adherence to LPD. If it is possible to remove protein from rice, it would minimize the need to cut down on main dishes and make it easier for patients to follow the LPD. We developed exclusive technology for digesting and removing protein from rice grain using microorganism-derived enzyme product, and technology for processing the Low-Protein Rice (LPR) thus obtained into a palatable food product. By combining these technologies, we can reliably manufacture delicious, high quality, low protein rice product, which can be eaten repeatedly as staple. Our LPR products, “PLC Rice” series are helpful to enhance the quality of mealtimes for CKD patients by increasing their range of food choices. It is therefore reasonable to say that PLC Rice products offer high added value, as it not only facilitates adhesion to LPD but also add satisfaction and contentment to daily meals, helping to enhance the quality of life of patients with CKD.

Glucosylceramide (GlcCer), a representative sphingolipid in cell membranes of plants and fungi, is known to have certain benefits, such as prevention of intestinal impairment and improved skin moisturizing, when consumed. Recently, incidence rates of intestinal impairments have increased in East Asian countries due to changes of people’s diet and life style. Therefore, the occurrence of these impairments needs to be prevented through dietary improvement and supplements containing GlcCer. The in vitro and in vivo effects of GlcCer on colon impairment were explored in our previous studies, with focus on sphingolipid structure. Conversely, plant cell membrane contents such as GlcCer are known to be difficult to extract due to the thick cell wall. Therefore, human and other mammals may not be able to utilize GlcCer when digesting food of plant origin. To confirm this hypothesis, we investigated the effects of polished rice and the extract on intestinal impairment. In addition, we discuss the intestinal function of GlcCer contained in polished rice and the relationship between GlcCer and other lipophilic functional components.

Processing adds value to agricultural products, making them more nutritious and economically competitive. Brown rice, by its unremoved bran, contains substantial amounts of protein, dietary fiber, minerals and vitamins; while buffalo’s milk has higher protein and calcium and lower cholesterol than other dairy milks. These were suitable ingredients to develop healthy and nutritious value-added product. An ice cream sandwich was developed using brown rice flour (BRF) substituted at 0, 40, 50 and 60% (wt/wt), and fresh buffalo’s milk. Acceptability of the product was determined through a consumer survey (n=100; 15 to 30 y old). Consumer sensory evaluation showed that cracker substituted with 50% BRF complemented with buffalo’s milk-based ice cream produced an acceptable ice cream sandwich. This resulted in a brown rice cracker ice cream sandwich (BRICS) that has 164 kcal, 8 g fat, 5.7 g protein, 20 g carbohydrates and key minerals. Product testing revealed that taste, mouthfeel, and aroma were the top attributes considered by respondents in buying ice cream products, and BRICS achieved high acceptability rating in these attributes. BRICS obtained an overall acceptability rating of 8.9 in a 9-point hedonic scale. Eighty eight percent (88%) of the respodents were willing to buy BRICS at PhP15-20. Therefore, BRICS is a convenient, nutritious, and marketable value-added product made from BRF and buffalo’s milk.

Rice starch is gradually used as a food ingredient. The characteristics of native starch are limited for using in some products. Therefore, microwave heating which is a non-chemically method was used for modify rice starch in this study. Changing of rice starch properties during microwave heating was investigated aimed for improving food product quality. Pasting properties of native starch (NS) showed the highest value for pasting temperature (66.8°C) and pasting viscosity (peak=3,583 cP, trough=1,542 cP, final=2,805 cP and setback=956 cP) than microwave treated rice starch (MRS) at 4 different time periods (10 s, 20 s, 30 s and 40 s). The results of pasting viscosity among MRS at 4 different time periods showed the lower values when increasing heating time. MRS at 40 s (MRS_40S) gave the lowest pasting temperature (52.9°C) which was needed lower temperature to gelatinize starch. NS had significant lower To (60.0°C), Tp (68.8°C), and Tc (75.5°C), and higher enthalpy (12.22 J/g) than the MRS. To, Tp and Tc of MRS was increased when treated time increasing, while enthalpy was decreased due to starch was gradually gelatinized and loss of crystallinity. XRD patterns of NS were found to be A-type because it showed peak of 2θ at 15°, 17°, 18° and 23° while XRD pattern of MRS_40S was changed and displayed peak only at 2θ (V-type). These changing of XRD patterns may due to loss of crystallinity during heating. The results indicated that microwave heating could change rice starch properties, especially MRS_40S displayed complete gelatinization. In addition, MRS_40S could be applied for using as texture improver for some food products which needs low viscosity e.g. soup, curry sauces and some beverages.

Glutamate decarboxylase (GAD) is an important enzyme in biological metabolisms acting on catalyzing the irreversible α-decarboxylation of L-glutamic acid to γ-aminobutyric acid (GABA) and CO₂, which was focused in this study. Three rice varieties different in color were germinated at different times and used for crude GAD extraction. Crude GADs with an optimal germination time from germinated black (GBR), red (GRR), and white (GWR) rice were evaluated for enzymatic properties, including the effect of pHs, temperatures, and concentrations of both L-glutamic acid and pyridoxal 5′-phosphate (PLP). Crude GAD with optimum enzymatic properties was selected to be partially purified using ammonium sulfate (AMS) precipitation. The obtained GAD was supplemented to soymilk and determined for GABA content. All crude GADs from germinated rice at 10 germination days presented the highest enzyme activity. For enzymatic properties, crude GADs showed the highest activity at pH in a range of 5.6-6.0 at 60ºC. The Km values of crude GADs were in the range of 7.68-8.06 mM for L-glutamic acid and 0.15-0.20 μM for PLP and were the lowest in crude GAD from GBR. GAD from GBR presented the highest enzyme activity in the fraction with 50% saturation (v/v) after AMS precipitation and it was purified for 14.61 folds. The addition of this GAD (1.0%, v/v) resulted in the increasing of GABA content in soymilk to 53.79 mg/100 mL, accounted for 1.23 times compared with control.

Xylooligosaccharides (XOS) and arabinoxylooligosaccharides (AXOS), potential prebiotics, can be produced from rice bran arabinoxylan (RBAX) using commercial endoxylanase enzymes. However, differences in rice bran cultivars and endoxylanase enzyme types may affect extracted oligosaccharides (OS) yields. This study investigated extracted OS structures derived from three different RBAX using two commercial endoxylanase enzymes. RBAX extracted from commercially defatted rice bran (CDRB) yielded the greatest OS amount (456.69 mg/g RBAX), followed by that of the San-Pah-Tawng1 (SPT1) cultivar (231.7 mg/g RBAX), and lastly, the Chai-Nat1 (CN1) cultivar (172.57 mg/g RBAX), as evidenced via Ultraflo L enzyme hydrolysis. Ultraflo Max enzyme hydrolysis produced a similar trend, however, OS amounts from all RBAX sources were remarkably lower (83.39 mg/g RBAX extracted from CDRB, 27.05 mg/g RBAX from SPT1 cultivar, and 21.53 mg/g RBAX from CN1 cultivar). Interestingly, 3²-α-L-Araf-(1-4)-β-D-xylobiose (A³X) was the primary AXOS product in all RBAX hydrolysates prepared by Ultraflo Max. RBAX extracted from CDRB solubilized by Ultraflo L (45.67% weight of RBAX) had higher OS yields than that obtained via Ultraflo Max (8.3% weight of RBAX). Ultraflo L was therefore a suitable commercial enzyme for short-chain OS conversion from RBAX.

Previously, we found an unidentified sphingolipid in cabbage, and determined it as phytoceramide 1-phosphate (PC1P). PC1P is found to be produced from glycosylinositol phosphoceramide (GIPC) by the action of phospholipase D (PLD) activity. Although GIPC is abundant sphingolipid, especially in cruciferous vegetables, amount of daily intake, digestibility and nutritional activity of GIPC are not well understood. Here, we investigated amounts of GIPC and PC1P in vegetables. GIPC was found in all vegetables examined (13 kinds) at levels 3-20 mg/100 g (wet weight). On the other hand, PC1P was present in limited vegetables which show higher GIPC-PLD activity, such as inner cabbage leaves (5.2 mg/100 g). Because PC1P is formed during homogenization by activated GIPC-PLD, level of PC1P in boiled cabbage leaves was very low. Although digestibility of GIPC is unknown at present, a portion of dietary GIPC is considered to be converted to PC1P during mastication by plant-derived GIPC-PLD activity in some vegetables.

γ-Oryzanol (OZ), a functional substance found in rice bran, consists of multiple molecular species. In both in vitro and in vivo studies, the researches exploring the various function of rice bran OZ have been conducted for a long time, and it has become clear that OZ has a lot of pharmaceutical activities. It is assumed that each type of OZ molecular species may have different effects. In contrast, the profile behaviour of OZ inside the body has not been fully understood. This article reviews the previous studies about the digestion, absorption, metabolism, and effects of rice bran OZ and also introduces the new method to evaluate the OZ metabolic fate by using high-performance liquid chromatography (HPLC) combined with tandem mass-spectrometry (MS/MS) which has higher selectivity and sensitivity.

Vitamin E is a natural lipophilic vitamin, and the most famous function of vitamin E is an antioxidant activity. Because we have α-tocopherol transfer protein, many vitamin E-related reports are about α-tocopherol. Recently, other vitamin E isoforms, tocotrienols are focusing. Because tocotrienols have unique biological functions such as induction of apoptosis, neuroprotective and anti-obesity effects. Tocotrienols contain in annatto, palm, whole wheat and rice bran. Rice is a typical food in the East Asian countries and Japan. Recently, intake of whole rice is a popular in young women of Japan. Previously, we demonstrated that treatment with tocotrienols on the neuronal cells shows a strong antioxidant effect compared to the tocopherols. In this review, I introduce about neuroprotective and anti-obesity effects of tocotrienols. I would like to show daily intake of whole rice is very good for our health in this review.

Chalk is an inferior characteristic of rice because it leads to the poor milling quality. In addition, chalky rice is generally considered to have poor cooking and eating qualities. However, the data on the poor cooking and eating qualities of chalky rice is limited, especially in high amylose Thai chalky rice varieties. Therefore, this work aimed to compare the microstructure, water migration during cooking, texture and sensorial qualities of four Thai chalky rice varieties, Prachin Buri2 (PB2), Khao Bahn Nah432 (KBN432), Ayutthaya1 (AY1), and Plai Ngahm Prachin Buri (PNPB), with the translucent Thai rice variety, Phitsanuplok2 (PSL2). The loosely packed cell structure in all chalky rice varieties was observed under scanning electron microscope. KBN 432 had the highest degree of chalkiness. Water migrated in the KBN432 with the fastest speed. All cooked chalky rice had lower hardness than the translucent rice, except AY1. Softness scores of chalky rice samples were higher than translucent rice. However, there was no difference in overall acceptability between chalky rice and translucent rice. Therefore, chalky rice varieties studied in this work may be used for consumption with the same quality to the translucent rice variety.

The effects of potato starch, isolated from Snowden (SD) and Kitahime (KH) varieties, on cecal fermatation properties in rats were evaluated. In high-amylose cornstarch (HAS), SD and KH groups, cecal acetate and total short-chain fatty acid concentrations were increased and cecal pH was lowered compared to control (CON) group. Further, cecal immunoglobulin A levels were increased and cecal ammonia-nitrogen, p-cresol, skatole and indole concentrations were lowered in HAS, SD and KH groups compared to the CON group. Therefore, potato starch might possess beneficial intestinal fermentation properties.

The BADH1 was characterized by investigating its association to aroma, drought and salinity stress through sequence and gene expression analysis using the selected aromatic rice accessions from Central Luzon State University, Philippines. Polymorphisms including SNPs, were observed in genomic analysis between the resistant check and the susceptible varieties during saline condition. On the other hand, BADH1 transcript level in tolerant varieties revealed that during salt treatment, the salt tolerant check Pokkali and moderately salt tolerant accession Leyte Special have increased transcript level compared to non-treated saline condition relative to actin. The downstream investigation of the BADH1 using genomic and transcriptomic approach is important information to elucidate the molecular mechanism of fragrance development among aromatic rice in CLSU and its response to abiotic stresses.

Salt is an important seasoning that adds a salty taste to enhance or suppress other tastes in cooking. Porridge is treated with salt, even with the addition of a small amount of salt to tighten its taste. This salty taste intensity is also influenced by the amount of bittern component contained in the salt because not only the bittern component but also the change of pH affects the degree of swelling and penetration into rice. However, excessive salt intake causes lifestyle-related diseases. For that reason, salt intake reduction is recommended. When salt and citric acid are added to the porridge simultaneously, the contrasting effects of acidity and saltiness enhance the salty flavor, allowing for the reduction of salt intake.

Gluten-free rice breading (RB) is generally prepared by shredding of gluten-free rice bread. It is an alternative product for Celiac patients, who are gluten allergic. The aim of this research was to formulate gluten-free rice bread formula by using composited rice flour (RF) and pre-germinated brown rice flour (PGBRF) from two Thai rice cultivars, Pathum-Thani1 (15% amylose) and Phitsanulok2 (27% amylose) at the ratio of 1:1, by considering the structural properties of bread, health benefit of breading, and the properties of breading as coating material of fried frozen croquette (C-) and compared to those of samples prepared from wheat flour. Increasing PGBRF from 0% to 50% in gluten-free rice bread formula increased the puffed cell wall of air cell in gluten-free rice bread. Antioxidative activity of RB containing 50% PGBRF (RB-50%) was 4 and 9 times higher than RB without PGBRF (RB-0%) and wheat breading (WB), respectively. WB contained 356,289 mg/kg of gluten, while RB contained less than 2 mg/kg of gluten, which could be labeled “gluten-free”. When compared all breading samples as coating material of C-, oil absorption of C-RB-50% (14.32%) was 3 times lower than that of WB (44.36%). Therefore, the RB-50% had health benefits for consumers who are suffered from Celiac disease and also other health-conscious consumers considering the higher antioxidative properties and lower oil uptake than the consumption of WB.

Miniature air bubbles with a diameter of less than 200 nm were generated by a nanobubble aerator, and nanobubble water (NBW) was eventually obtained using the gas-liquid mixing system with hydrodynamic function. As the air bubbles have long lifetime and high gas solubility in the liquids, NBW is stable in nature and inside contains sufficient dissolved oxygen. At present, there is no report on the use of NBW to replace ordinary water to cultivate microalgae. In this research, effect of NBW on the growth and metabolism of different microalgae, including Haematococcus lacustris and Botryococcus braunii was investigated. The result demonstrated that the growth of H. lacustris and B. braunii was increased by NBW and the highest promotion ratio was up to 44% and 26%, respectively. For H. lacustris, the astaxanthin content in the NBW treatment group was also improved compared to the control group. As the main product of B. braunii, lipid content in the dry matter was decreased after the treatment of NBW, but total lipid production was significantly higher than that of the control group. In general, NBW could serve as the potentially effective tool to promote the growth of microalgae in the future.

Paramagnetic species (radicals) related pigments in Thai purple rice were investigated by electron paramagnetic resonance (EPR), X-band (9 GHz) EPR imaging (EPRI), and HPLC. The location and distribution of the paramagnetic species in purple and white rice were determined by EPR and EPRI. EPR primarily detected three paramagnetic species in purple rice, which were identified as organic radicals, Mn²⁺, and Fe³⁺ based on the g-values and hyperfine components of the EPR signals. Noninvasive two-dimensional (2D) EPRI revealed that these stable radicals are primarily located in the pigmented region of purple rice, while very few radicals were observed in the interior of the rice. HPLC revealed that the major compounds were cyanidin-3-O-glucoside and peonidin-3-O-glucoside. EPR, EPR imaging, and HPLC results indicate that the stable radicals contain the radical state of anthocyanins and are mostly found within the pigmented embryo region of purple rice. They could be either associated with antioxidant activities or could be one of the products of their oxidative decomposition.