Jie-Lun Hu

Polysaccharide from seeds of Plantago asiatica L. increases short-chain fatty acid production and fecal moisture along with lowering pH in mouse colon.

Mice (20.0 ± 2.0 g, n = 48 per group) were given 30 days oral administration of polysaccharide from Plantago asiatica L. seeds at the dose of 0.4 g/kg body weight by gavage to investigate the effects of the polysaccharide on mouse colon. Results showed that the concentrations of total short-chain fatty acids (SCFA), acetic, propionic, and n-butyric acids in mouse colonic content of polysaccharide treated group were all significantly higher than that of control group (water) (p < 0.05). In addition, moisture of mouse colonic content of polysaccharide treated group was also notably higher than that of the control group (p < 0.05) indicating the intake of polysaccharide from P. asiatica L. resulted in a stronger water-holding capacity for colonic content throughout the experimental period. Furthermore, a decreased pH (from 7.5 ± 0.1 to 7.2 ± 0.1) was observed in mouse colon of the polysaccharide treated group compared with the control group (pH from 7.5 ± 0.1 to 7.5 ± 0.1). These results suggested that the intake of the polysaccharide from P. asiatica L. might be beneficial for the colon health.

Artificial simulated saliva, gastric and intestinal digestion of polysaccharide from the seeds of Plantago asiatica L.

The saliva, gastric and intestinal digestion of polysaccharide from Plantago asiatica L. seeds was investigated in vitro. It was found that salivary amylase had no effect on the polysaccharide; however, the polysaccharide was influenced in later gastrointestinal digestion. A steady decrease in molecular weight (M(w)) of the polysaccharide from 1903.1±93.0 to 4.7±0.2 kDa was observed as digestion time increased. Meanwhile, the reducing ends were increased from 0.157±0.009 to 0.622±0.026 mM, indicating the decrease of M(w) may due to the breakdown of glycosidic bonds. In addition, there was no monosaccharide released throughout the whole digestion period, suggesting that the gastrointestinal digestion did not result in a production of free monosaccharide. These results may provide some information on the digestion of polysaccharide from P. asiatica L. in vitro, and may contribute to the methods of studying the digestion of other carbohydrates.

High pressure homogenization increases antioxidant capacity and short-chain fatty acid yield of polysaccharide from seeds of Plantago asiatica L.

Physiological properties of homogenized and non-homogenized polysaccharide from the seeds of Plantago asiatica L., including antioxidant capacity and short-chain fatty acid (SCFA) production, were compared in this study. High pressure homogenization decreased particle size of the polysaccharide, and changed the surface topography from large flake-like structure to smaller porous chips. FT-IR showed that high pressure homogenization did not alter the primary structure of the polysaccharide. However, high pressure homogenization increased antioxidant capacity of the polysaccharide, evaluated by 4 antioxidant capacity assays (hydroxyl radical-scavenging, superoxide radical-scavenging, 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH)-scavenging and lipid peroxidation inhibition). Additionally, the production of total SCFA, propionic acid and n-butyric acid in ceca and colons of mice significantly increased after dieting supplementation with homogenized polysaccharide. These results showed that high pressure homogenization treatment could be a promising approach for the production of value-added polysaccharides in the food industry.

Polysaccharide from Seeds of Plantago asiatica L. Affects Lipid Metabolism and Colon Microbiota of Mouse

Polysaccharide from the seeds of Plantago asiatica L. was given via oral administration to mice (0.4 g/kg body weight, 30 days) to observe its effects on mouse nutrient metabolism and colon microbiota. It was found the polysaccharide intake could lower the apparent absorption of lipid. Total triglyceride, cholesterol, and atherogenic index in blood serum with total lipid and cholesterol levels in liver of polysaccharide group mice were all significantly lower than those of the control group (p < 0.05). Furthermore, the effect of the polysaccharide intake on mouse colon bacterial communities was investigated. Mice from the polysaccharide group showed a higher colon bacterial diversity than the control group. Bacteroides sp., Eubacterium sp., butyrate-producing bacteria Butyrivibrio sp., and probiotics Bifidobacterium bifidum , Lactobacillus fermentum , and Lactobacillus reuteri in mouse colon were all increased after polysaccharide intake. These indicated that the intake of polysaccharide from P. asiatica L. could be beneficial for lipid metabolism and colon microbiota.

In vitro effects of a novel polysaccharide from the seeds of Plantago asiatica L. on intestinal function.

Effects of a novel polysaccharide (PLP) from the seeds of Plantago asiatica L. on intestinal function were investigated in vitro. Results showed that PLP had notable influence on slowing down glucose diffusion and inhibiting α-amylase activity. These might help prolong blood glucose response and hence control the postprandial glucose concentration. PLP could also decrease pancreatic lipase and protease activities, which may help lower the levels of serum lipids and modify protein digestibility. In addition, PLP was able to bind bile acids and may reduce cholesterol level. These results suggested that PLP may have potential benefits for human intestinal function and might be used as a potential ingredient in functional food applications.

Antimicrobial activity of saponin-rich fraction from Camellia oleifera cake and its effect on cell viability of mouse macrophage RAW 264.7

BACKGROUND As a by-product of oil production, several million tons of Camellia oleifera cake is discarded every year in China. The aim of this study was to evaluate the antimicrobial activity of a saponin-rich fraction isolated from C. oleifera cake and investigate its effect on the cell viability of RAW 264.7, a macrophage-like cell line present in almost all mouse tissues. RESULTS The saponin-rich fraction was isolated from C. oleifera cake in several steps and had a saponin content of 95.42 ± 0.10% (w/w). It showed significant inhibitory activity against the bacteria Staphylococcus aureus, Escherichia coli and Bacillus subtilis and the fungi Mucor racemosus, Aspergillus oryzae, Rhizopus stolonifer, Saccharomyces cerevisiae and Penicillium glaucum, with minimum inhibitory concentrations of 31.3, 31.3, 62.5, 250, 250, 250, 31.3 and 125 µg ml(-1) respectively. In addition, mouse macrophage RAW 264.7 pretreated with the saponin-rich fraction (80-200 µg mL(-1) ) exhibited a significant loss of cell viability in a dose-dependent manner. CONCLUSION These results may be useful for the future application of saponins from C. oleifera cake. However, the potential use of the saponin-rich fraction as an antimicrobial agent should be decided according to the target micro-organisms in order to avoid causing harm in humans.

Microbial short-chain fatty acid production and extracellular enzymes activities during in vitro fermentation of polysaccharides from the seeds of Plantago asiatica L. treated with microwave irradiation.

Effects of microwave irradiation on microbial short-chain fatty acid production and the activites of extracellular enzymes during in vitro fermentation of the polysaccharide from Plantago asiatica L. were investigated in this study. It was found that the apparent viscosity, average molecular weight, and particle size of the polysaccharide decreased after microwave irradiation. Reducing sugar amount increased with molecular weight decrease, suggesting the degradation may derive from glycosidic bond rupture. The polysaccharide surface topography was changed from large flakelike structure to smaller chips. FT-IR showed that microwave irradiation did not alter the primary functional groups in the polysaccharide. However, short-chain fatty acid productions of the polysaccharide during in vitro fermentation significantly increased after microwave irradiation. Activities of microbial extracellular enzymes xylanase, arabinofuranosidase, xylosidase, and glucuronidase in fermentation cultures supplemented with microwave irradiation treated polysaccharide were also generally higher than those of untreated polysaccharide. This showed that microwave irradiation could be a promising degradation method for the production of value-added polysaccharides.

In vitro fermentation of the polysaccharides from Cyclocarya paliurus leaves by human fecal inoculums.

In vitro fermentation of polysaccharide from Cyclocarya paliurus leaves by human fecal inoculums was investigated by determining the changes in contents of neutral and reducing sugar and pH value, consumption of monosaccharide and production of short-chain fatty acids (SCFAs). During fermentation, the content of neutral sugar and reducing sugar decreased as fermentation time increased except that the content of reducing sugar increased within the fermentation time 0.5h. The pH value significantly dropped from 7.2 to 6.04. Remarkably, the greatest yields and the fastest consumption of galacturonic acid were found and the yield of glucose and arabinose were relatively high. The dominant SCFAs, which were acetic acid, propionic acid and n-butyric acid, significantly increased. These results showed that polysaccharide was partly fermented, glycosidic bonds with galacturonic acid being more susceptible to be attacked by gut bacteria and galacturonic acid might be deemed as the main producer of acetic acid.

Metabolism and Health Effects of Phyto-estrogens

ABSTRACT Phyto-estrogens are plant-derived compounds that can exert various estrogenic and anti-estrogenic effects, and are usually used as a natural alternative to estrogen replacement due to their health benefits, including a lowered risk of osteoporosis, heart disease, breast cancer, and menopausal symptoms. Phyto-estrogens are also considered as endocrine disruptors due to their structure similar to human female hormone 17-β oestradiol. However, the issue of whether phyto-estrogens are beneficial or harmful to human health remains unknown, as this may depend on the dose, form, level and duration of administration of phyto-estrogens, and influence by genetics, metabolism, gut physiology, age, diet, and the health status of individuals. Clarification on this issue is necessary for the sake of their two-side effects on human health and rapidly increasing global consumption of phyto-estrogens. This review mainly includes the metabolism of phyto-estrogens and weighs the evidence for and against the purported health benefits and adverse effects of phyto-estrogens.

Study on Dendrobium officinale O-Acetyl-glucomannan (Dendronan). 7. Improving Effects on Colonic Health of Mice.

This research was aimed to study the effect of Dendrobium officinale polysaccharide (Dendronan) on colonic health. Mice were fed Dendronan at doses of 40, 80, and 160 mg/kg body weight for 0, 10, 20, and 30 days, respectively. Results showed that Dendronan, which has a special structure formed by mannose and glucose, rich in O-acetyl groups, exhibited improving effects on colonic and fecal parameters of Balb/c mice. After Dendronan feeding, the content of short-chain fatty acids (SCFAs), colon length and index, and fecal moisture were increased, whereas colonic pH was decreased and defecation time was shortened. All of these changes were significantly different between polysaccharide-treated groups and the control group (p < 0.05). These findings suggested that an adequate intake of Dendronan is beneficial to the process of fermentation and regulation of colonic microenvironment, thus playing a role in the maintenance of colonic health.