• Journal of Food Hygiene and Safety
• /
• v.15 no.1
• /
• pp.5-12
• /
• 2000

Lipid peroxidation is one of the main manifestations of oxidative damage and has been found play an important role in the toxicity and carcinogenesis of many carcinogens. This study was carried out to investigate the effects of aflatoxin B$_1$co-administrated with antioxidant vitamins on lipid contents and fatty acids components of liver in mice. For this work, vita-min C and vitamin E, the major antioxidants, were administrated with 10 mg/kg and 63.8 mg/kg respectively, through intraperitoneal(i.p) injection to male ICR mice, and 0.4 mg/kg of the AFB$_1$injected by i.p. 1hr later. The results were as follows: two fold amounts of free cholesterol, triglyceride, and total cholesterol in serum and liver of mice treated with only AFB$_1$were observed, when compared to those of mice co-administrated with antioxidant vitamins. However, the levels of phospholipids in serum and liver of mice treated with only AFB$_1$were decreased. Concerning to fatty acids composition of liver from AFB$_1$-treated mice, P/S ratio was shown more low level in cholesteryl ester, triglyceride, total cholesterol and phospholipid than those of mice co-administrated with antioxidant vitamins. In these data which provide with a reliable evidence on their antioxidantal effects to aflatoxicosis.

• Korean Journal of Microbiology
• /
• v.52 no.4
• /
• pp.463-470
• /
• 2016

The enzymatic degradation of xylans is the most versatile way to obtain the high value-added functional compounds or the fermentable sugars for renewable energy. The endo-${\beta}$-xylanases are the major enzymes which hydrolyze the internal ${\beta}$-1,4-linkages of xylan backbones to produce the mixtures of xylooligosaccharides including xylobiose and xylotriose. Among them, glucuronoxylanase GH30 can exclusively hydrolyze the internal ${\beta}$-1,4-linkages of xylans decorated with methylglucuronic acid branches. In the present study, two xylanolytic enzyme (PaXN_10 and PaGuXN_30) genes were cloned from Paenibacillus amylolyticus KCTC 3005, and expressed in Escherichia coli, respectively. PaXN_10 (38.7 kDa) belongs to the endo-${\beta}$-xylanases GH10 family, while PaGuXN_30 (58.5 kDa) is a member of glucuronoxylanase GH30. They share the same optimal reaction conditions at $50^{\circ}C$ and pH 7.0. Enzymatic characterization proposed that P. amylolyticus can utilize the hardwood glucuronoarabinoxylans via the cooperative actions of xylanases GH10 and GH30. The extracellular PaGuXN_30 is secreted into the medium and hydrolyzes glucuronoarabinoxylans to release a series of aldouronic acid mixtures with a methylglucuronic acid branch. The resultant products being transported into the microbial cell are successively degraded into the smaller xylooligosaccharides by the intracellular PaXN_10, which will be utilized for the cellular metabolism.