Antidiabetic properties of polysaccharide- and polyphenolic-enriched fractions from the brown seaweed Ascophyllum nodosum.
نویسندگان
چکیده
We screened seaweed species from Atlantic Canada for antidiabetic activity by testing extracts for alpha-glucosidase inhibitory effect and glucose uptake stimulatory activity. An aqueous ethanolic extract of Ascophyllum nodosum was found to be active in both assays, inhibiting rat intestinal alpha-glucosidase (IC50 = 77 microg/mL) and stimulating basal glucose uptake into 3T3-L1 adipocytes during a 20-minute incubation by about 3-fold (at 400 microg/mL extract). Bioassay-guided fractionation of the A. nodosum extract showed that alpha-glucosidase inhibition was associated with polyphenolic components in the extract. These polyphenolics, along with other constituents appeared to be responsible for the stimulatory activity on glucose uptake. However, attempts to further concentrate this activity through fractionation techniques were unsuccessful. A crude polyphenol extract (PPE), an enriched polyphenolic fraction (PPE-F1) and a polysaccharide extract (PSE) were prepared from commercial A. nodosum powder and administered to streptozotocin-diabetic mice for up to 4-weeks by daily gavage at 200 mg/kg body mass. PPE and PPE-F1 improved fasting serum glucose level in diabetic mice; however, the effect was only statistically significant at day 14. In addition, PPE-F1 was shown to blunt the rise in blood glucose after an oral sucrose tolerance test in diabetic mice. Mice treated with PPE and PPE-F1 had decreased blood total cholesterol and glycated serum protein levels compared with untreated diabetic mice, whereas PPE also normalized the reduction in liver glycogen level that occurred in diabetic animals. All 3 A. nodosum preparations improved blood antioxidant capacity.
منابع مشابه
Effects of soilless growing media and extracts of brown seaweed Ascophyllum nodosum on the growth of Robinia pseudoacasia L. Behzad Kaviani1*, Naser Negahdar2 and Davood Hashemabadi1
Ascophyllum nodosum is the most important commercial seaweed. Seaweeds have been applied as soil conditioners in improving plant growth and development in agricultural crops. In current study and for the first time, extracts of brown seaweed A. nodosum improved the growth of Robinia pseudoacasia L., an ornamental tree. This research investigated the effect of cultivation beds (sand, perlite, co...
متن کاملThe Cultivable Surface Microbiota of the Brown Alga Ascophyllum nodosum is Enriched in Macroalgal-Polysaccharide-Degrading Bacteria
Bacteria degrading algal polysaccharides are key players in the global carbon cycle and in algal biomass recycling. Yet the water column, which has been studied largely by metagenomic approaches, is poor in such bacteria and their algal-polysaccharide-degrading enzymes. Even more surprisingly, the few published studies on seaweed-associated microbiomes have revealed low abundances of such bacte...
متن کاملEffect of foliar application of seaweed Ascophyllum nodosum extract on morpho-physiological characteristics of bean (Phaseolus vulgaris) under water stress
Seaweed extract can improve the physicochemical properties of the soil and has a favorable effect on the plant growth and development due to having high nutrient content, high water holding capacity, plant growth regulators and beneficial microorganisms. The aim of this experiment was to investigate the effect of Ascophyllum nodosum extract, a brown alga, on the morphophysiological characterist...
متن کاملEffect of epiphytism on reproductive and vegetative lateral formation in the brown, intertidal seaweed Ascophyllum nodosum (Phaeophyceae)
*To whom correspondence should be addressed. Email: akraberg@awi-bremerhaven.de Communicating editor: K. Kogame. †Present address: Alfred-Wegener Institute for Polar and Marine Research, Biological Station Helgoland, Kurpromenade 201, 27489 Helgoland, Germany. Received 22 June 2005; accepted 15 May 2006. doi: 10.1111/j.1440-1835.2006.00441.x Effect of epiphytism on reproductive and vegetative l...
متن کاملAscophyllum nodosum enriched bread reduces subsequent energy intake with no effect on post-prandial glucose and cholesterol in healthy, overweight males. A pilot study.
It is well recognised that the consumption of seaweed isolates (such as alginate) successfully reduce energy intake and modulate glycaemic and cholesterolaemic responses. However, to date, the effect of adding whole seaweed to bread has not been widely investigated. Hence, this study aims to investigate the acceptability of Ascophyllum nodosum enriched bread as part of a meal, and measure its e...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Canadian journal of physiology and pharmacology
دوره 85 11 شماره
صفحات -
تاریخ انتشار 2007