Flavonoids are known to be effective scavengers of free radicals. In particular, proanthocyanidins are flavonoids that possess cardiovascular protection, antioxidative activities, and immunomodulatory activities. Here, we evaluated proanthocyanidin contents in the total polyphenolic compounds of pine needle extracts prepared by hot water, ethanol, hexane, hot water-hexane (HWH), and hot water-ethanol (HWE). Analysis of each extract indicated that the ethanol extract contained the highest proanthocyanidin concentration. The HWH and hexane extracts also contained relatively high concentrations of proanthocyanidin. On the other hand, proanthocyanidin content analyses out of the total polyphenolic compounds indicated that the HWH extract contained the highest content. These results suggest that HWH extraction is a suitable method to obtain an extract with a high level of pure proanthocyanidins and a relatively high yield. The HWH extract possessed superior activity in diverse antioxidative analyses such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferrous ion chelating (FIC), and ferric-ion reducing power (FRAP) assays. In addition, upon assessing the effects of the pine needle extracts on macrophages (Raw 264.7 cell), the HWH extract exhibited the highest activity. In this study, we discerned an efficient extraction method to achieve relatively pure proanthocyanidins from pine needles and evaluated the biological functions of the resulting extract, which could potentially be used for its efficacious components in functional food products.

Random mutagenesis was performed on beta-agarase, AgaB, from Zobellia galactanivorans to improve its catalytic activity and thermostability. The activities of three mutants E99K, T307I and E99K-T307I were approx. 140, 190 and 200%, respectively, of wild type beta-agarase (661 U/mg) at 40 degrees C. All three mutant enzymes were stable up to 50 degrees C and E99K-T307I had the highest thermostability. The melting temperature (Tm) of E99K-T307I, determined by CD spectra, was increased by 5.2 degrees C over that of the wild-type enzyme (54.6 degrees C). Activities of both the wild-type and E99K-T307I enzymes, as well as their overall thermostabilities, increased in 1 mM CaCl2. The E99K-T307I enzyme was stable at 55 degrees C with 1 mM CaCl2, reaching 260% of the activity the wild-type enzyme held at 40 degrees C without CaCl2.

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We investigated the effects of fermented Sargassum thunbergii (FST) on platelet aggregation and serum lipid levels in rats made obese by a high fat diet. Six-week-old male SD-rats were randomly assigned to four groups as CON, HF-CON induced by high fat diet (HF), ST supplemented with HF (HF-ST100), and the fermented ST supplemented with HF group (HF-FST100). After 6 weeks, the results showed that the final weight and weight gain had decreased in the HF-FST100 group compared to the HF-CON group. Also, the food efficiency ratio was significantly reduced in the HF-FST100 group compared to HF-CON. The organ weights other than heart and spleen were significantly lower in the HF-FST100 group than in the HF-CON group. The levels of serum GOT and GPT significantly decreased in the HF-FST100 group over the HF-CON group. In addition, the total cholesterol, triglyceride and LDL-cholesterol levels were lower in the HF-FST100 group than in HF-CON, while the HDL-cholesterol level was higher in the HF-FST100. The ability of platelet aggregation of groups supplemented with FST was lower than the HF-CON group. These results suggest that FST may be beneficial in improving lipid profile and platelet aggregation in obesity.