Hypolipidemic Effect of the Autoclaved Extract Prepared from Pea (Pisum sativum L.) Pods In Vivo and In Vitro.

By autoclaving, we obtained a polyphenol and dietary fiber from pea (Pisum sativum L.) pods in parallel without acid or alkali treatment or organic solvent extraction. Rats fed a high-sucrose (HS) diet containing 3% autoclaved extract (AE) for 4 wk exhibited significantly lower serum triglyceride and total cholesterol levels than rats fed a HS diet. AE and soluble dietary fiber (SDF) from AE exhibited pancreatic lipase inhibitory activity at 13.3 mg/mL in vitro. AE and insoluble dietary fiber (IDF) from AE adsorbed cholesterol. In total, 30% and 10% of a cholesterol micelle were significantly adsorbed by 2,000 mg of AE and 100 mg of IDF from AE in 7 mL, respectively. The amount of bifidobacteria in the cecum of the AE group was significantly increased compared with that in the HS group. These results suggest that AE has hypolipidemic, bifidogenic potential.

Hypolipidemic and bifidogenic potentials in the dietary fiber prepared from Mikan (Japanese mandarin orange: Citrus unshiu) albedo.

The albedo is the white part of the citrus peel, which acts as a water reservoir for the juice sacs, seeds and leaves in times of drought. As the functionality of the albedo is unknown, we examined in this study the hypolipidemic and bifidogenic potentials of dietary fiber (DF) prepared from the Mikan (Japanese mandarin orange: Citrus unshiu) albedo. The albedo was obtained from Mikan harvested in Arida, Wakayama Prefecture, and total DF (TDF), water soluble DF (SDF) and water insoluble DF (IDF) were extracted. Albedo TDF contained arabinose (37.21%), galactose (16.05%), xylose (18.30%) and glucose (13.94%), but did not contain detectable amounts of galacturonic acid. Albedo SDF inhibited the enzymatic digestion of triolein by pancreatic lipase in vitro. The SDF, at a concentration of 80 mg per 6 mL of substrate solution, significantly inhibited the activity of this enzyme (>50%). As compared to a control group on a 5% cellulose diet, rats fed a diet containing 1% albedo TDF for 4 wk showed significantly decreased serum triacylglycerol concentrations, increased fecal lipid excretion, and no changes in hepatic lipid content (triacylglycerol, total cholesterol, and phospholipid) or serum concentrations of total cholesterol or phospholipid. Consumption of albedo TDF also increased the number of bifidobacteria in the cecum. In this report, we have demonstrated that consumption of albedo TDF increased the levels bifidobacteria in the rat cecum, and decreased serum triacylglycerol concentrations due to the accelerated lipid excretion into the feces caused by the inhibition of pancreatic lipase.

The screening method of a bifidogenic dietary fiber extracted from inedible parts of vegetables.

Total dietary fiber (DF) was extracted from the inedible parts of vegetables such as peel of taro and Chinese yam, pea pod, broad bean pod, and broad bean testa. Effects of these fibers on the growth of bifidobacteria were determined by two kinds of experiments: one was to determine the increase of Bifidobacterium longum JCM1217 (B. longum) in medium containing DF, the other was an in vitro fermentation of the DF by anaerobic slurries of mixed human fecal or rat cecal microbiota. Anaerobic culture was carried out for 48 h in both experiments. In the pure culture of B. longum, the significant increase of bacterial number was observed as compared with 0 h in the medium containing the DF from peel of Chinese yam, pea pod and broad bean pod (p<0.05). On the other hand, bacterial number was decreased in the medium containing the DF from the peel of taro and broad bean testa. We selected the DF from pea pod because of its highest bifidogenic property in human fecal microbiota. In the fermentation of DF from pea pod by rat cecal microbiota, bifidobacteria and lactobacilli were increased. Bacteroidaceae and clostridia were decreased. These results suggested that DF from pea pod had possibility as a prebiotic. The bifidogenic property was affected by the sugar composition of DF.