In the present study, the effect of exogenously supplemented amino acids on growth of Arabidopsis thaliana was comprehensively studied. After cultivation at 25°C for 10 days in the presence or absence of various amino acids, the inhibitory effect of each amino acid was analyzed qualitatively and quantitatively by taking photographs and by measuring body weight and lengths of hypocotyl and first true leaf of A. thaliana seedling, respectively. d-Ala, l-and d-Ser, l-Lys, d-Arg, l- and d-His, l-Met, l-Leu, l-allo-Ile, l-Ile, l-Val, l- and d-Tyr, l- and d-Trp and l- and d-Phe exhibited inhibitory effect. Other amino acids showed no inhibitory effect. The results suggested that, in the event of growth inhibition, the hydrophobicity, hydrophilicity, basicity and aromaticity of the amino acid side chain reflected in terms of enantioselectivity to some extent. The degree of the inhibitory effect depended on kinds of amino acid. These d- and l-amino acids repressed the increase of body weight and the elongation of hypocotyl and first true leaf of A. thaliana seedling concentration-dependently, and these results suggested that they inhibited the growth of whole plant body, not particular part of A. thaliana.

Phosphorus (P) is used as phosphates in a wide variety of processed food, such as fish cake, processed meat, cheese, frozen bakery products and carbonated beverages. Depending on individual dietary patterns, such additives may increase the intake of P. Excess dietary P is associated with a risk of inhibiting calcium (Ca) absorption in the intestine. Phosphates are added to surimi to improve water retention and prevent alteration during freezing. However, there is a tendency for consumers to avoid surimi because of the added phosphates. Currently, no information is available concerning the P and Ca solubility effect of fish protein (FP), which is contained in surimi. Therefore, we investigated the influence of FP on P and Ca solubility in vitro experiment. Experimental diets were formulated as follows: normal-P (0.3% P wt/wt, potassium dihydrogenphosphate) diet, high-P (1.5% P wt/wt, potassium dihydrogenphosphate) diet and high-polyphosphate (1.5% P wt/wt, sodium polyphosphate) diet. The protein source of each experimental diet was FP or chicken breast protein (CP). The experimental diets were exposed to simulated gastric digestion including HCl and pepsin for 120 min (pH 2.0) and then small intestinal digestion including NaHCO₃ and pancreatin for 120 min (pH 7.4). When the high-polyphosphate diets were digested, the FP diet tended to be higher Ca solubility than the CP diet (p = 0.10). When the normal-P and high-P diets were digested, there were no significant differences in the Ca solubility between the FP and CP diets. The obtained results indicate that FP might enhance Ca solubility under excess polyphosphate conditions.

Snow room (Yukimuro) storage is a traditional method for the preservation of foods in the snowy areas of Japan. A Yukimuro provides an environment with low temperature and high humidity that preserves food quality and improves their taste.

The aromatic compounds of roasted coffee beans are divided into three groups: an aldehyde group containing undesirable odors, a pyradine group containing sweet and roasted aromas, and a furan group containing components that characterize coffee aroma.

Previously, we reported that aldehydes of roasted coffee beans stored in a Yukimuro were markedly decreased, and aroma components were changed in a favorable. In a sensory assessment, the taste of coffee stored in a Yukimuro was better than that stored in a refrigerated room and a room under normal temperature.

In this study, we demonstrated the effect of Yukimuro storage on favorable changes in the aromatic components of roasted coffee beans by model experiments, using coffee flavor compounds and a refrigerator with the capability of constant low temperature and high humidity. 11 compounds (two aldehydes, four pyradine analogs, and five furan analogs) were used as coffee aromas. They were attached to glass beads and then stored in packages with an outward air valve in a refrigerated room (R: 2°C -5°C , 45% -60% humidity), a constant low temperature and high humidity room (Yukimuro: 2°C , 99% humidity), or a room under normal temperature (NT: 20°C , 45% -60% humidity) for four weeks. After storage, the flavor compounds remaining on the glass beads were extracted with water and assayed using gas chromatography.

All flavor compounds were greatly diminished in NT but remained relatively well preserved in R and Yukimuro. However, in the Yukimuro, aldehydes were significantly reduced, whereas pyradines and furans were relatively well preserved. In this study, the proportion of pyradines and furans increased in the Yukimuro. This result suggests that the Yukimuro storage enhances desirable aromatic components by reducing undesirable aldehydes and enhancing desirable pyradines and furans.

Menadione, a naphtoquinone compound with vitamin K acitivity in animal, shows cellular toxicity, which may be ascribed to the reactive oxygen species. This work analyzed the menadione-dependent generation of reactive oxygen species in yeast. Menadione inactivated aconitase, the most sensitive enzyme to oxidative stress, in the presence of reducing reagent such as ascorbate or NADH and NADPH. No requirement of azide, an inhibitor of catalase, for the inactivation of aconitase by menadione with NADPH indicates that superoxide anion radical produced plays a principal role for the inactivation . Ascorbate stimulated the inactivation of aconitase by menadione with NADPH or NADH in the presence of azide, suggesting the generation of hydrogen peroxide. Menadione-dependent generation of reactive oxygen species can be explained by the NAD(P)H-quinone oxidoreductase 1-mediated reduction of menadione to quinol form, which participates in the production of reactive oxygen species in yeast. Possible role of ascorbate and glutathione in the reduction of menadione was also discussed.

The present study was conducted to clarify the effects of supplemental β-cryptoxanthin in maternal mice during pregnancy and lactation on IgA antibody-secreting cells (ASC) in the intestine and mammary glands of lactating mice. From 6.5 days postcoitus to 7 or 14 days postpartum (dpp), maternal mice were fed rodent feed or 50 mg/kg β-cryptoxanthin-supplemented rodent feed. Supplemental β-cryptoxanthin increased the numbers of IgA ASC and the mRNA expressions of IgA C-region, CCL25 and CCL28 in the jejunum at 14 dpp. Supplemental β-cryptoxanthin had no effects on the numbers of IgA ASC in the ileum and mammary glands, although supplemental β-cryptoxanthin increased the mRNA expression of IgA C-region in the ileum and mammary glands at 14 dpp. Supplemental β -cryptoxanthin had no effects on IgA concentrations in serum, stomach contents, intestines and feces of neonatal mice. These results imply that supplemental β-cryptoxanthin in maternal mice during pregnancy and lactation is effective to increase the numbers of IgA ASC in the jejunum during late lactation.

In this study, we investigated whether there were any regional or inter-variety differences in trace element contents between tea leaves grown in the isolated island of Yakushima and those grown in Shizuoka and Kyushu, and whether the trace element contents are effective in distinguishing the leaves produced in different regions within a small area.

The trace element contents in 32, 14, and 7 samples of tea leaves produced in Yakushima, Shizuoka, and Kyushu, respectively, were measured using an ICPS1000IV.

The scatter plot from discriminant analysis of varieties showed that each variety formed a cluster, but no differences in the trace element content were observed. The scatter plot from discriminant analysis of the samples from Yakushima, Shizuoka, and Kyushu showed that the samples from each region formed a distinct cluster, and it was possible to identify the origin based on the trace element content. No regional differences were found in the trace element content when analysis involved the samples collected in Yakushima only. However, when cultivated regions were categorized into two areas, the Yakushima samples were found to form two groups based on the Mg and Mn contents, those from northeast and southeast areas.

Trace elements such as manganese (Mn), zinc (Zn) and copper (Cu) are essential elements, but excess amounts of these elements are known to cause many neurodegenerative diseases including Alzheimer’s disease (AD) and Parkinson’s disease (PD). The risk of excessive intake of Mn, Zn and Cu is increased by taking food plus supplements. Some of botanical or animal origin supplements have been reported to contain high concentrations of Mn, Zn and Cu. We investigated the effects of long-term exposure to Mn, Zn and Cu on learning and memory in aged mice. 20-week-old ICR-JCL male mice were given 100 ppm Mn, Zn or Cu via drinking water for 58 weeks. The effects of Mn, Zn and Cu on non-spatial long-term memory were investigated using step-through-type passive avoidance task in male aged mice after 56-weeks administration. In the retention trials of the passive avoidance test, latencies to enter a dark compartment were shorter in the Mn- and Cu-exposed mice, compared to control mice. The behavioral test indicated the possibility that long-term exposure to Mn and Cu inhibited long-term memory.

Glycosphingolipids (GSLs) are complex macromolecules in cell membranes that play important roles in various biological processes. Fungi contain several types of GSLs that are distinct from those of mammals, but little is known about their physiological functions, metabolic regulation, or biosynthetic pathways. Most fungal species that possess fungal neogala-series GSLs (FNG-GSLs) are resistant to aureobasidin A (AbA), an antifungal agent that inhibits glycosylinositolphosphoceramide (GIPC) synthesis. We have previously reported that Mariannaea elegans has FNG-GSLs in its cell membrane, despite the fact that it is sensitive to AbA. In this study, we demonstrated that M. elegans contains GIPCs, which explains its sensitivity to AbA. We also found that both cell growth and GSL composition of M. elegans were affected by the presence or absence of different sugars in the culture medium. In contrast, sugars had no effect on the phenotypes and GSLs of AbA-resistant Rhizopus sp. lacking GIPCs. Further analysis revealed that FNG-GSL production can be modulated by the addition of 600 mM NaCl in a glucose-containing medium. Finally, sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of Golgi proteins from M. elegans showed that at least nine proteins were present exclusively in cells producing FNG-GSL, suggesting that those proteins are potential candidates for FNG-GSL synthesis.

Abbreviations: AbA, aureobasidin A; ER, endoplasmic reticulum; FNG-GSLs, fungal neogala-series GSLs; Gal-Cer, β-galactosylceramide; Glc-Cer, β-glucosylceramide; GSLs, glycosphingolipids; GIPCs, glycosylinositolphosphoceramides; IPC, inositolphosphoceramide; SDS-PAGE, sodium dodecyl sulfate polyacrylamide gel electrophoresis; TLC, thin-layer chromatography

Raw cow’s milk (test milk) and feed samples were obtained from two dairy farms in the coastal area of southeast Dianchi Lake, Kunming City, Yunnan Province, China in July and September, 2013, to determine their concentrations of cadmium (Cd) and lead (Pb) by inductively coupled plasma mass spectrometry (ICP-MS). As references, the concentrations of Cd and Pb in raw milk (control milk) and feed samples of cows conventionally reared in Japan were also determined. Concentrations of Cd were not significantly different between test milk (0.39 ± 0.23 μg/l in July and 1.73 ± 2.47 μg/l in September) and control milk (0.55 ± 0.26 μg/l). However, concentrations of Pb were higher in test milk (23.37 ± 6.83 μg/l in July and 26.22 ± 10.83 μg/l in September) than in control milk (10.43 ± 5.23 μg/l) (P < 0.01). The mean concentrations of Pb in test milk in July and September exceeded the maximum recommended level established by the European Commission, and the concentrations of Pb in some feeds from the study farms (corn stem and leaf feed and broad-bean stem feed) were also above the values given in Japanese standards. These results indicate the possibility of Pb contamination in milk and feeds at dairy farms in the present study area. Hence, special attention should be paid to Pb residues in milk and feed at dairy farms in this region of China.

Hijiki (Sargassum fusiforme ***) plant having genital organs was harvested on the Hime Coast, Kushimoto, Wakayama Prefecture, Japan, and the concentrations of accumulated arsenic, calcium, iron, magnesium, manganese, potassium, and zinc were determined. The fresh plants were washed thoroughly and cut at a length of 10 cm along the stalk from the bottom to the top of the plants. The twigs of the lower, middle and upper portions of the respective sections were separated to twig-stalks, twigs’ large leaves and twig’s small leaves. The genital organs of each section were also separated. The respective samples were weighed and stored under -40°C until freeze-dried. The lyophilized samples were decomposed with conc HNO₃ and HClO₄ on an electric furnace, and the respective elements were determined with an atomic absorption spectrophotometer. These plants, having genital organs contained rather constant levels of calcium, 11.7 ± 1.4 * (genital organs), 〜 12.2 ± 0.9 * (leaves) mg Ca/g of dried tissues. They also contained rather constant levels of arsenic, 83.6 ± 12.07 * (stalks) 〜 110 ± 27.2 * (leaves) μg As/ g dry weight of tissues. Genital organs of some sections showed lesser arsenic accumulation than in most other sections, suggesting that accumulation started later in these sections. The concentrations of magnesium, manganese and zinc have not become uniform yet. However, the correlation coefficients between the accumulated magnesium and manganese were 0.93 to 0.69, and those between the accumulated manganese and zinc were 0.59 to 0.67. Thus, these elements seem to be accumulating more abundantly. Iron accumulation was, in average, 100.3 to 134.0 μg Fe/ g dry weight of tissues, but seems to be further continuing, as their accumulated concentrations had not become uniform yet. ( * : average ± standard deviation)

The aim of this study was to investigate the influence of D-amino acids (D-AAs) on the food flavor profile of fermented foods. First, the content of fifteen D-AAs in eight soy sauces, eight soybean pastes and eight cheeses were analyzed by the HPLC method using derivatization reagents. Ten D-AAs in the soy sauces, ten D-AAs in the soybean pastes and twelve D-AAs in the cheeses were detected, and the minimum value of total D-AA concentration among the all foods was 1.3 mM. Second, two sensory evaluations by the Constant stimuli method and the TimeIntensity method were conducted to evaluate the influence of the D-amino acids at 1 mM concentrations on the profile of the five basic tastes (sourness, bitterness, saltiness, sweetness, and umami). Five basic taste solutions (0.025% citric acid, 0.075% caffeine, 1% NaCl, 4% sucrose, and 0.5% MSG) were prepared, to which were added 1 mM D-AA. From the results of the sensory evaluations, we found that D-Asp significantly suppressed sourness and bitterness, and that D-Pro strengthened continuity, sweetness, and umami compared with L-enantiomer. These results suggest that D-AAs play crucial roles in the fundamental tastes of fermented foods.

A considerable problem of insufficient vitamin intake exists among athletes. The objective of this study is to reveal the total thiamin concentration in whole blood of university student athletes and general students of the same age group, and to investigate the possibility of a lack of thiamin due to a difference in the amount of exercise. The results showed that the distribution of thiamin concentration for both male and female general students was within the standard value, and that there was an almost normal distribution. In contrast, for the distribution of thiamin concentration in athletes, there was a lower frequency marking higher values compared with that in general students. In addition, as the average thiamin concentration in both male and female student athletes was significantly lower than that in general students, we hypothesized the possibility of a latent thiamin deficiency among student athletes. To clarify this issue, other blood examination items should be further reviewed.

Introduction: Zinc (Zn) is an essential trace element in cellular metabolism and skeletal mineralization. It is well known that 90% of Zn in the entire body is found in muscle and bone. Fibroblast growth factor 23 (FGF23) is a key regulator ofPi homeostasis and contributes to several hypophosphatemic disorders through decreased expression of the Na-Pi co-transporter type IIa (Na/Pi IIa) and Na/Pi IIc on the renal cortical brush border membrane. Whether FGF23 regulates Pi metabolism in Zn-deficient (ZnD) rats is unclear. Therefore, we measured the serum levels of FGF23 and 1,25-dihydroxy vitamin D3 (1,25-VD₃) in ZnD rats, as well as the mRNA levels of bone FGF23, renal Klotho, Na/Pi IIa and Na/Pi IIc. Methods: The bone mineral density (BMD) of the femur and urinary Pi excretion estimated using a dual X-ray absorption method. Control groups consisted of rats on a paired calorie Zn-sufficient diet (Pf), and rats that were allowed to feed freely (F). Results: Compared with the Pf group, the serum levels of 1,25-VD₃ in the ZnD group were significantly reduced. Bone FGF23 mRNA expression, serum levels of FGF23, and urinary Pi excretion were significantly increased compared with the Pf group. The expression of Na/Pi IIc was significantly decreased compared with the F groups. Expression of Klotho mRNA was inhibited by Zn deficiency. Conclusion: These results suggest that Zn deficiency may inhibit 1,25-VD₃ synthase, resulting in increased serum FGF23. Moreover, increased FGF23 may reduce the reabsorption of Pi, resulting in a decrease in BMD.

The liver-derived peptide hormone hepcidin is a master regulator of systemic iron homeostatis. Hepcidin binds to an iron exporter ferroportin expressing on the basolateral membrane of enterocytes and induces the internalization and degradation of ferroportin, leading to a decrease in intestinal iron absorption. Various stimuli such as body iron stores, inflammation, erythropoiesis, and hypoxia affect hepcidin expression through the transcriptional regulation. This mini-review summarizes current understandings on the factors affecting hepcidin expression.