Metabolic Fate and Expectation of Health Benefits of [U-14C]-Sucrose Inhibited from Digestion Using Morus alba Leaf Extract.

Morus alba leaf extract (MLE), a strong inhibitor of sucrase, suppresses blood glucose elevation following sucrose ingestion. To investigate that sucrose inhibited from digestion using MLE is utilized through gut microbiota, [U-14C]-sucrose solutions with or without MLE were administered orally to conventional and antibiotic-treated rats, and the excretion of 14CO2 and H2 produced by gut microbiota was measured for 24 h. After an administration of [U-14C]-sucrose to conventional rats, the unit excreted 14CO2 peaked at 4 h, and the cumulative 14CO2 excreted over 24 h was approximately 60% of the radioactivity administered. No H2 was excreted. Following an administration of [U-14C]-sucrose and MLE in conventional rats, the unit excreted 14CO2 peaked later, at 8 h, and was significantly lower (p<0.05). The cumulative 14CO2 excreted over 24 h was equal in both groups, although there was a time lag of 2-3 h in rats given [U-14C]-sucrose and MLE. The amount of H2 excreted by these rats peaked 8 h after administration. Following the administration of [U-14C]-sucrose and MLE to antibiotic-treated rats, the unit excreted 14CO2 peaked lower, and the cumulative 14CO2 excretion over 24 h was approximately 40%. In this group, H2 was minimally excreted. H2 and 14CO2 produced by gut microbiota were excreted simultaneously. In conclusion, sucrose inhibited from digestion using MLE was fermented spontaneously by gut microbiota and was not excreted into feces. In addition, it confirmed that H2 excretion could be used directly to indicate the degree of fermentation of nondigestible carbohydrates.

Comparison of utilisation and fermentation of highly cross-linked phosphate starches produced from two different plant origins, potato and tapioca in rats and humans.

The utilisation and fermentation of highly cross-linked phosphate starches made from two different origins, potato (HXL-P) and tapioca (HXL-T) were investigated in rats and humans. HXL-P and HXL-T were highly resistant to digestion by carbohydrate enzymes and were also resistant to fermentation by gut microbiota in rats. The postprandial blood glucose scarcely increased after administration of HXL-P or HXL-T in healthy humans. Incremental AUC of both HXL-P and HXL-T for 180 min was significantly lower than that of glucose (p < .05). Breath hydrogen excretion was very low after oral administration of HXL-P or HXL-T, and AUCs of breath hydrogen excretion for 13 h after administration were significantly lower than that of fructooligosaccharide as a reference of fermentation (p < .05). These results show that HXL-P and HXL-T were hardly digested and were highly resistant to fermentation. In conclusion, HXL-P and HXL-T could be good low-energy bulking ingredients to replace wheat flour.

Repeated ingestion of the leaf extract from Morus alba reduces insulin resistance in KK-Ay mice.

The objective of this study was to test the hypothesis that repeated ingestion of diet containing the leaf extract from a Morus alba (LEM) maintains the postprandial hypoglycemic response and suppresses the progression of insulin resistance in high-sucrose diet-fed KK-Ay mice with spontaneous type 2 diabetes mellitus (DM). This hypothesis is based on our previous studies where LEM competitively inhibited intestinal disaccharidases and suppressed the elevation of postprandial plasma glucose and insulin levels. Ten KK-Ay mice in each group were raised on 0%, 3%, or 6% LEM powder-containing high-sucrose diets for 8 weeks. Blood samples were collected to measure fasting plasma glucose and insulin levels at weeks 2, 4, and 7 after the start of feeding. Urinary glucose excretion was monitored as a parameter of insulin resistance in 3-day intervals. Fasting plasma glucose level and urinary glucose excretion were significantly lower in both 3% and 6% LEM groups compared with the control group throughout the experiment. The plasma insulin of the 6% LEM group was significantly lower compared with the 3% LEM and control groups. Maintenance of low blood glucose and insulin delayed the onset time of urinary glucose excretion and were reflected by the ratio of additional LEM to sucrose in the diet. We observed the suppressive effects on the progression of hyperglycemia and hyperinsulinemia in the repeated ingestion of the LEM-containing diet. Namely, repeated ingestion of the LEM-containing diet reduces insulin resistance and may delay the appearance of DM, especially type 2 DM. Therefore, daily intake of LEM may be suitable for the prevention of obesity and DM.

Inhibitory effects of extractives from leaves of Morus alba on human and rat small intestinal disaccharidase activity.

The inhibitory effect on human and rat intestinal disaccharidase by the extractive from the leaves of Morus alba (ELM) containing 0.24 % 1-deoxynojirimycin equivalent and its inhibitory activities were investigated by the modified Dahlqvist method. In the presence of 1000-fold diluted ELM solution, the sucrase activity of four human samples was inhibited by 96 % and that of maltase and isomaltase by 95 and 99 %, respectively. The activities of trehalase and lactase were inhibited by 44 and 38 %, respectively. The human disaccharidase activities varied from sample to sample because the samples were obtained from different resected regions after surgery. However, the ratio of the inhibitory effect for sucrase, maltase, isomaltase, trehalase and lactase was very similar among the four samples, and also that of resembled rat intestinal disaccharides. The inhibitory constant of the 1-deoxynojirimycin equivalent for sucrase, maltase and isomaltase was 2.1 x 10(-4), 2.5 x 10(-4) and 4.5 x 10(-4) mm, respectively, and these inhibitory activities were shown, using rat brush border membrane vesicles, to be competitive. These results demonstrate that digestion is inhibited when an appropriate amount of ELM is orally ingested with sucrose or polysaccharide in man. When ELM was orally administered in a sucrose solution to fasted rats, the elevation in blood glucose was significantly suppressed, depending on the concentration of ELM given. These results suggest that ELM could be used as an ingredient in health foods and in foods that help to prevent diabetes.

Composition of milk obtained from unmassaged versus massaged breasts of lactating mothers.

BACKGROUND: The Oketani method is a program of breast massage and clinical counseling developed by the midwife Satomi Oketani. The purpose of this study is to examine the effects of the method on the quality of breast milk by determining the chemical composition of the milk before and after massage. METHODS: Milk samples were obtained immediately before and after massage from healthy, exclusively breast-feeding Japanese mothers at two different periods of lactation one <3 months the other >3 months after parturition. Lipids, whey protein, casein, lactose, ash, and total solids in milk were measured in milk samples. The gross energy content of milk was estimated. RESULTS: Breast massage significantly increased lipids in the late lactating period but not in the early lactating period. In the early lactating period casein was increased by breast massage but was not significantly affected in the late lactating period. Breast massage caused a significant increase in total solids from the first day to 11 months post partum. The gross energy in the late lactating period was significantly increased by breast massage but not in the early lactating period. Lactose was not significantly changed by breast massage. CONCLUSIONS: Breast massage improves the quality of human milk by significantly increasing total solids, lipids, and casein concentration and gross energy. The milk of mothers treated by Oketani breast massage may improve the growth and development of infants.