Healthy foods such as beans, mushrooms, vegetables, and seafood and healthy dietary patterns such as the Mediterranean diet and Japanese food have higher concentrations of polyamines (spermine and spermidine). The continuous intake of high-polyamine foods has been shown to increase whole blood polyamine levels in mice and humans. In addition, high-polyamine chow inhibited aging-associated pathological changes in Jc1:ICR male mice and extended their lifespan. Aging is accompanied by decreased DNA methyltransferase activities, increased proinflammatory status, and enhanced abnormal gene methylation status, which is considered to be part of the pathogenesis of aging-associated diseases. In vitro and in vivo experiments have shown that polyamine supplementation reversed such changes induced by aging and polyamine-deficiency. In addition, polyamines have many biological activities that may contribute to the inhibition of lifestyle-related diseases such as diabetes, hyperlipemia, and arteriosclerosis. The possible role of dietary polyamines in human health is discussed.
Specialty breads substituted with non-wheat flour like purple sweet potato have been attracting attention because of their added nutrients, flavor, and color. Although the addition of non-wheat flour to specialty breads often results in lower loaf volume, this can be improved by enzyme treatments. In this context, this study investigated the effects of purple sweet potato powder (PSPP) substitution and enzyme treatments using α-amylase and hemicellulase on gassing power (GP), gas retention of dough (GRD), color and specific loaf volume (SLV) of bread. Results showed that the addition of PSPP produces bread crumbs with light purple color but low GRD and SLV of bread. On the other hand, α-amylase and hemicellulase improved the GRD, SLV and GP of PSPP-substituted bread by degrading the damaged starch and hemicellulose. Thus, these improved properties indicate acceptable quality of the bread.
The objective of this study was to investigate the effect of inoculation with a probiotic strain Lactobacillus casei ŁOCK 0900 and ageing time on the formation of free amino acids (FAAs) and biogenic amines in dry-cured pork loins. The predominant FAAs were glutamic acid, threonine, alanine and leucine. The total FAAs content increased significantly (p < 0.05) during ageing. After the longest examined ageing time, FAAs content in the loins inoculated with a probiotic strain represented significant increase of about 25% in comparison with the control sample. Differences in FAAs concentration were determinant for taste attributes of examined loins. Histamine was not detected in any sample, irrespective of ageing time. Inoculation with a probiotic strain L. casei ŁOCK 0900 proved to be a protective measure against the accumulation of cadaverine, putrescine and tryptamine even though the loins inoculated with L. casei were characterized by higher availability of FAAs.
A consumer-oriented methodological approach for the quality evaluation of Cheddar cheese as a typical fermented food was developed. Datasets were obtained from gas chromatography/olfactometry (GC/O) analysis and sensory evaluation of 10 Cheddar cheese samples. The GC/O analysis identified 43 aroma components under the categories of 14 aroma descriptors. Consumer evaluation of palatability was performed by 59 housewives. Factor analysis of the GC/O data identified aroma descriptors that have positive or negative correlations with palatability scores. Twelve aroma components were prioritized using stepwise partial least-squares regression with variable importance in projection (PLS-VIP). An artificial neural network (ANN) model was constructed to demonstrate the nonlinear relationships among the raw GC/O data of the samples and the palatability scores. Coupling stepwise PLS-VIP and ANN resulted in successful identification and ranking of aroma components contributing to the palatability of Cheddar cheese, and in modeling their nonlinear relationships.
Rice is typically consumed after milling, a process of removing the husk and bran layers on rice surface. The degree of bran residue remaining on milled rice directly affects the rice quality. This work proposed to detect the bran residue on a single rice grain using fluorescence fingerprint-derived imaging nondestructively. In the experiment, combinations of fluorescence excitation and emission wavelengths that could effectively distinguish the bran and endosperm pixels were identified through fluorescence fingerprint (FF) spectroscopy. Fluorescence images of milled rice samples at these wavelengths were acquired. A support vector machine classifier was then developed to predict the bran residue on rice grains using the FF-derived images as the inputs. It was demonstrated that the proposed method could observe the distribution of bran residue and could predict the percentage of bran residue on milled rice grains with an error of 3.54%.
Processing of olive fruits using a three-phase extraction system for the production of virgin olive oil was analyzed to clarify the material balance of olive fruit components, i.e., oil, water, carbohydrates, proteins, minerals and polyphenols. The estimated total olive material balance based on mass flow indicated a final oil extraction yield of around 83.3%, with an initial olive fruit mass flow of 500 kg/h. The remaining oil was discharged as a by-product, mainly in olive cake (8.9%) and olive mill water (7.8%). The material balance of carbohydrates showed that the majority were discharged in olive cake (73.3 kg/h) and olive mill water (27.7 kg/h). The material balance of polyphenols, the most important functional compounds in olives, was determined because of their importance to olive oil chemical stability. Results showed an increase in polyphenols content during malaxation operation (17.6%), which was correlated with several enzymatic reactions directly reflected in the composition of virgin olive oil.
Identification of fake green tea is performed by sensory assessment which has significant drawbacks in terms of objectivity. In this works, sensory assessment and electronic tongue were utilized for identifying fake green tea. Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) were used to assess the feasibility and effectiveness of discrimination of electronic tongue. The PCA and HCA revealed a distinct separation between samples, which corresponded with the results of sensory assessment. Artificial Neural Network (ANN), including back propagation neural network with the Levenberg-Marquardt training algorithm (LMBP) and radial basis function neural network (RBF), were used as an automatic classifier and showed good performance in the training set and the prediction set. The results suggest that electronic tongue can be used for distinguishing fake Dongting Biluochun Tea from certified products characterized by protection of geographical indications product certification with pattern recognition methods instead of sensory assessment.
Dried salted fishes are some of the more common high quality, but cheap protein sources in the Philippines. Furthermore, production of salted fishes is the most common livelihood activity in near-shore villages in the country. This work sought to characterize and compare quality attributes of sun- and mechanically dried salted herrings in order to determine whether such products comply with established national standards; and identify key quality attributes that need to be addressed and improved by processors. The microbiological quality parameters including Total Plate Counts, Yeasts and Molds, Coliforms and Escherichia coli of all sun- and mechanically dried samples were compliant with national standards. Staphylococcus aureus of one sun-dried sample was however 0.7 log CFU/g higher than the limit and should be addressed through good hygienic and manufacturing practices. Physicochemical quality attributes of the samples did not significantly vary; while the sun-dried samples from Quezon were consistently given higher sensory scores. The results established in this work can serve as baseline information for the continuous effort to improve and maintain quality and safety of such products, especially that the country has just ratified the Philippine Food Safety Act of 2013; and as the country prepares for the Association of Southeast Asian Nations (ASEAN) integration in 2015.
The oral intake of probiotic microorganisms has been investigated as a potential approach to prevent IgE-associated allergic diseases, including atopic dermatitis (AD). However, the effects of potentially edible wild yeast strains of the genus Saccharomyces on allergic symptoms remain poorly understood. In this study, we investigated the effects in the NC/Nga AD mouse model of Saccharomyces paradoxus P01 (P01), a wild strain selected based on its suppressive effect on IgE production in vitro. Compared to animals on a P01-free diet, mice fed a P01-supplemented diet had a markedly reduced incidence of skin lesions and picryl chloride-induced ear thickening and inflammation. Serum IgE levels and IgE production by spleen cells in mice fed the P01-supplemented diet were significantly lower than those of control mice. These results suggest that oral intake of specific IgE-suppressive wild strains of Saccharomyces yeast may be effective in suppressing IgE production and alleviating IgE-associated allergic symptoms.
To evaluate the suppressive effects of green rooibos (Aspalathus linearis) unfermented tea on postprandial hyperglycemia, we orally administered four carbohydrates with or without green rooibos extract (GRE) and its major flavonoid aspalathin (Asp). GRE significantly suppressed the elevation of blood glucose levels after glucose, maltose, and starch intake. Asp also lowered the levels for all four carbohydrates. To clarify the mechanism underlying these results, we performed an intraperitoneal glucose tolerance test (IPGTT) and measured the ability of GRE and Asp to inhibit the activities of carbohydrate-hydrolyzing enzymes in vitro. In IPGTT, GRE and Asp did not show suppressive effects on blood glucose, while they dose-dependently inhibited the activities of α-glucosidase and α-amylase in vitro. These results showed that GRE and Asp suppress the elevation of blood glucose levels. It was indicated that these effects may result from the suppression of glucose absorption and the inhibition of carbohydrate-hydrolyzing enzyme activities by GRE and Asp.
Two widely used spices, Chili pepper (Capsicum frutescens L. var. conoides Bailey) and Sichuan pepper (Zanthoxylum bungeanum Maxim.) inoculated with Escherichia coli, Salmonella enterica Typhimurium and Aspergillus niger were irradiated with gamma ray. All inoculated samples were irradiated with a series of dosages. The efficacy of irradiation to inactivate pathogens was investigated. The results showed that irradiation at doses 4.00 kGy and 5.00 kGy was appropriate for eliminating almost all E. coli and S. Typhimurium in two peppers, respectively. A. niger was undetectable in chili and Sichuan pepper at doses 1.50 kGy and 1.00 kGy radiation. The D10-values of E. coli, S. Typhimurium and A. niger in Sichuan pepper were 0.81, 0.93 and 0.20 kGy , and 0.82, 0.69 and 0.49 kGy in chili pepper. The results indicated that irradiation at appropriate doses is a promising approach for producing safe and pathogen-free peppers for consumers.
The methanol extracts of wasabi leaves (Wasabia japonica Matsumura) from Shizuoka, Japan have been found to inhibit the production of nitric oxide (NO) in an in vitro assay using murine macrophage J774.1 cells stimulated with lipopolysaccharide. Fourteen known compounds, including five phenylpropanoid glycosides (1 – 4 and 9), three phenylpropanoids (5 – 7), a phenolic glycoside (8), two flavonoid glycosides (10 and 11), two terpenoids (12 and 13) and a carotenoid (14), were isolated from wasabi leaves collected from Shizuoka and their structures elucidated using spectroscopic methods. This study therefore represents the first reported isolation of compounds 8, 9, 12, 13 and 14 from wasabi leaves. 5-Hydroxy ferulic acid methyl ester (5) and all-trans-lutein (14) were found to inhibit NO production in J774.1 cells with IC50 values of 22 and 25 µM, respectively. The results therefore suggested that these compounds are the active components of wasabi leaves.
Yacon (Smallanthus sonchifolius) tuber contains fructooligosaccharides (FOS). FOS are known as prebiotics that beneficially affect the host, i.e., improve the intestinal flora balance and enhance the immunomodulatory potential. In this study, we investigated the effect of a yacon extract rich in FOS (YOS) on the intestinal flora and immune system of BALB/c mice sensitized and challenged with ovalbumin in comparison with an extract with acid-degraded FOS (YAH). During the 4-week test period, the amount of YOS intake was lower than that of YAH; however, a significant increase in body weight was not shown among any of the test groups. Sneezing events were observed in OVA-treated mice. It was found that administration of yacon FOS improved the intestinal flora. Further, it was suggested that administration of yacon-derived FOS could epidemiologically improve the Th1/Th2 cytokine balance through its prebiotic effect on the number of beneficial bacteria in the animal gut.
The aim of this study was to analyze four different acidifying strains of Lactobacillus delbrueckii subsp. bulgaricus and their influence on the quality of yoghurt. The results showed L. bulgaricus IM1 and L. bulgaricus IM2 were fast acidifying strains, and L. bulgaricus IM3 and L. bulgaricus IM4 were slow acidifying strains. When the four strains were mixed with Streptococcus thermophilus TA040, the fermentation time of the yoghurt starter culture LS1 (IM1 and TA040) and LS2 (IM2 and TA040) was shorter than that of the yoghurt starter culture LS3 (IM3 and TA040) and LS4 (IM4 and TA040). However, yoghurt samples fermented by LS3 and LS4 had weaker post-acidification, higher viscosity and more exopolysaccharide (EPS). In addition, the highest acetaldehyde and diacetyl contents were observed in yoghurt fermented by the slowest acidifying yoghurt starter culture (LS4). Therefore, selecting slow acidifying L. bulgaricus strain is a considerate design to integrate advantageous performance of strains.
The physiologically active substances of okara koji, a fermented soybean residue from tofu (bean curd) manufacturing, were examined. First, kojis were made with rice or barley using 14 different koji molds. Next, the acid degree, protease activity, antioxidative activity (DPPH radical scavenging activity), and angiotensin-converting enzyme (ACE) inhibitory activity of the kojis were measured. Four koji molds were selected for high levels of physiologically active substances. Finally, it was confirmed that kojis produced using the selected koji molds showed increased levels of physiologically active substances such as acid proteases and ACE inhibitory substances.
The incidence, intraspecific diversity and toxigenic profile of Bacillus cereus in the Yellow-Water were investigated. Of 50 samples tested, 17 (34%) were contaminated by B. cereus with 3.7 × 103 − 4.9 × 103 CFU/mL. The intraspecific diversity of B. cereus was observed by repetitive (GTG)5 sequence polymorphism-PCR, with six subtypes, and were further discriminated into seven subtypes by 16S-23S rRNA intergenic transcribed spacer. 94% of isolates contained at least 2 toxin genes of nheABC, hblCDA, cytK, entFM and EM1, but 6.0% carried none of them. The detection rates of nheABC, hblCDA, cytK and entFM were 94%, 88%, 46% and 70%, respectively. All isolates with nheABC could produce NHE, but of the isolates harbored hblCDA, 52% was positive for HBL. Only 6.0% isolates possessed EM1 and they were positive for emetic toxin assay. The results suggested that Yellow-Water needs stricter microbial standard as a fermented food flavor enhancer.
Natural killer (NK) cells play a critical role in early host defense against tumor and virus-infected cells. Here, we report that two coffee diterpenes, cafestol and kahweol, potentiate the cytotoxic activity of KHYG-1, an NK leukemia cell line, against the NK-sensitive cell line K562. Western blot analysis and quantitative real-time PCR indicated that cafestol and kahweol markedly enhanced the expression of granzyme B. While both diterpenes had no or little effect on the expression of other cytotoxic effector molecules, kahweol elevated the phosphorylated forms of ATF-2, c-Jun and CREB transcription factors, which might participate in granzyme B gene expression. These results suggested that cafestol and kahweol upregulate granzyme B expression by activating transcription factors, leading to enhanced cytolytic activity of NK cells.