Characterization, prebiotic and immune-enhancing activities of rhamnogalacturonan-I-rich polysaccharide fraction from molokhia leaves.

Plant-derived polysaccharides possess potential health benefits that improve intestinal health and the immune system. Molokhia leaves have a large amount of mucilage polysaccharide; in the present study, crude polysaccharide extract was prepared from molokhia leaves. The molecular weight of molokhia leaf polysaccharide fraction (MPF) was estimated to be 51.2 × 103 Da. Polysaccharide was methylated and the structure of MPF was mainly composed of rhamnogalacturonan-I structure with side chains, such as galactans and linear glucan (starch), as shown by GC-MS analysis. To study the biofunctional effects of MPF, its prebiotic and intestinal immune-enhancing activities were assayed in vitro. MPF exhibited good prebiotic activity, as shown by its high prebiotic scores, and increased contents of total short-chain fatty acids on five probiotic strains. In addition, MPF showed immune-enhancing activity on Peyer's patches, as revealed by the high bone marrow cell proliferating activity and production of immunoglobulin A and cytokines. These results demonstrate that MPF may be a potential beneficial prebiotic and intestinal immune-enhancer, which may have wide implications in the food industry.

Metabolomic unveiling of a diverse range of green tea (Camellia sinensis) metabolites dependent on geography.

Numerous factors such as geographical origin, cultivar, climate, cultural practices, and manufacturing processes influence the chemical compositions of tea, in the same way as growing conditions and grape variety affect wine quality. However, the relationships between these factors and tea chemical compositions are not well understood. In this study, a new approach for non-targeted or global analysis, i.e., metabolomics, which is highly reproducible and statistically effective in analysing a diverse range of compounds, was used to better understand the metabolome of Camellia sinensis and determine the influence of environmental factors, including geography, climate, and cultural practices, on tea-making. We found a strong correlation between environmental factors and the metabolome of green, white, and oolong teas from China, Japan, and South Korea. In particular, multivariate statistical analysis revealed strong inter-country and inter-city relationships in the levels of theanine and catechin derivatives found in green and white teas. This information might be useful for assessing tea quality or producing distinct tea products across different locations, and highlights simultaneous identification of diverse tea metabolites through an NMR-based metabolomics approach.

Metabolic dependence of green tea on plucking positions revisited: a metabolomic study.

The dependence of global green tea metabolome on plucking positions was investigated through (1)H nuclear magnetic resonance (NMR) analysis coupled with multivariate statistical data set. Pattern recognition methods, such as principal component analysis (PCA) and orthogonal projection on latent structure-discriminant analysis (OPLS-DA), were employed for a finding metabolic discrimination among fresh green tea leaves plucked at different positions from young to old leaves. In addition to clear metabolic discrimination among green tea leaves, elevations in theanine, caffeine, and gallic acid levels but reductions in catechins, such as epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and epigallocatechin-3-gallate (EGCG), glucose, and sucrose levels were observed, as the green tea plant grows up. On the other hand, the younger the green tea leaf is, the more theanine, caffeine, and gallic acid but the lesser catechins accumlated in the green tea leaf, revealing a reverse assocation between theanine and catechins levels due to incorporaton of theanine into catechins with growing up green tea plant. Moreover, as compared to the tea leaf, the observation of marked high levels of theanine and low levels of catechins in green tea stems exhibited a distinct tea plant metabolism between the tea leaf and the stem. This metabolomic approach highlights taking insight to global metabolic dependence of green tea leaf on plucking position, thereby providing distinct information on green tea production with specific tea quality.

[A case of chemical colitis caused by hydrogen peroxide enema].

Hydrogen peroxide is commonly used as a disinfectant that has been reported to cause chemical colitis. We report a case of 49 year-old man who presented with chemical colitis caused by self-inflicted hydrogen peroxide enema. In the sigmoidoscopic examination, diffuse erythematous and edematous mucosal change with multiple ulcerations and easy touch bleeding was noted from the rectum to the proximal sigmoid colon. Abdominal computed tomography showed diffuse wall thickening of the rectum and the sigmoid colon with inflammatory and reactive change at surrounding. The patient was treated with NPO, intravenous fluid, and antibiotic therapy. On 5th hospital day, abdominal pain and bloody stool disappeared, and the patient started oral feeding. He discharged on 6th hospital day with fully recovered state.

Geographical and climatic dependencies of green tea (Camellia sinensis) metabolites: a (1)H NMR-based metabolomics study.

The effects of climatic conditions on green tea metabolites in three different growing areas of Jeju Island, South Korea, were investigated through global metabolite profiling by (1)H nuclear magnetic resonance (NMR) spectroscopy. Pattern recognition methods, such as principal component analysis (PCA) and orthogonal projection on latent structure-discriminant analysis (OPLS-DA), revealed clear discriminations of green teas from the three different growing areas. Variations of theanine, isoleucine, leucine, valine, alanine, threonine, glutamine, quinic acid, glucose, epicatechin (EC), epigallocatechin (EGC), epigallocatechin-3-gallate (EGCG), and caffeine levels were responsible for the discriminations. Green teas grown in an area with high temperature, long sun exposure time, and high rainfall had higher levels of theanine but lower levels of isoleucine, leucine, valine, alanine, EC, EGC, EGCG, and caffeine than those grown in areas with relatively low temperature, short sun exposure time, and low rainfall. These results indicate that high temperature, long sun exposure, and high preciptation stimulate theanine synthesis in green tea during the spring season. This study highlights how metabolomics coupled with multivariate statistical analysis can illuminate the metabolic characteristics of green tea associated with climatic variables, thereby allowing for the assessment of quality strategy in green tea production.

Evidence of vintage effects on grape wines using 1H NMR-based metabolomic study.

The chemical composition of grape wines varies with grape variety, environmental factors of climate and soil, and bacterial strains, which can each affect the wine quality. Using (1)H NMR analysis coupled with multivariate statistical data sets, we investigated the effects of grape vintage on metabolic profiles of wine and the relationship between wine metabolites and meteorological data. Principal component analysis (PCA) showed a clear differentiation between Meoru wines that were vinified with the same yeast strain and Meoru grapes harvested from the same vineyard but with a different vintage. The metabolites contributing to the differentiation were identified as 2,3-butandiol, lactic acid, alanine, proline, gamma-aminobutyric acid (GABA), choline, and polyphenols, by complementary PCA loading plot. Markedly higher levels of proline, lactic acid and polyphenols were observed in the 2006 vintage wines compared to those of 2007 vintage, showing excellent agreement with the meteorological data that the sun-exposed time and rainfall in 2006 were approximately two times more and four times less, respectively, than those in 2007. These results revealed the important role of climate during ripening period in the chemical compositions of the grape. This study highlights the reliability of NMR-based metabolomic data by integration with meteorological data in characterizing wine or grape.