ABSTRACT
Mycoestrogen zearalenone [ZEA] is found in human foods and animal feeds. Its estrogenic potency mainly depends on its biotransformation fate. The hepatic biotransformation of ZEA in rainbow trout was investigated in this study. Various concentrations of ZEA were separately incubated with the hepatic microsomal and post-mitochondrial sub-fractions in the presence of NADPH, and the metabolites were determined by means of HPLC. Moreover, the rate of glucuronidation for ZEA and its reduced metabolites were estimated in the presence of uridine diphosphate glucuronic acid. beta-zearalenol [beta-ZOL] was found to be the major metabolite of ZEA by both sub-cellular fractions. The enzymatic kinetics analyses indicated that the alpha-ZOL and beta-ZOL production by microsomal fraction were 8- and 2-fold higher than those by post-mitochondrial fraction, respectively. High percentages of ZEA and its metabolites are conjugated with glucuronic acid at the lower concentrations. Data suggest that the hepatic biotransformation of ZEA in rainbow trout resulted in its detoxification as the main metabolite tends to be beta-ZOL with weak estrogenic property. Moreover, at certain concentrations, the produced metabolites are entirely conjugated with glucuronic acid, which may consequently cause a prolonged duration of action due to entero-hepatic cycle
Subject(s)
Oxidation-Reduction , Oncorhynchus mykiss , Biotransformation , Subcellular Fractions , Zeranol/analogs & derivativesABSTRACT
The application of antioxidant films is a promising strategy for controlling chemical spoilage of food. Antioxidant chitosan films incorporated with grape seed extract [GSE] were developed with the objectives of investigation of their characteristics. Chitosan film was developed by casting method and the effect of different concentrations of GSE [0, 0.5, 1 and 2%] on mechanical, color [accordance with hunter system [L* [luminosity], alpha* [redness], and b* [yellowness]], antioxidant characteristics, total phenol [TP], and swelling index [%SI] of films were evaluated. Generally, the tensile strength of GSE formulated films was influenced by the concentrations of GSE. The 2% GSE/ chitosan films revealed tensile strength similar to unsupplemented film. Concerning color of chitosan film, results indicated that by incorporating GSE, significant changes on L*, alpha*, b* values were appeared [p 0.05]. The antioxidant activity of GSE formulated films was considerable due to the high source of phenolics. This activity was affected by GSE concentrations, which were significant for film containing 0.5% [37.85%] 1% [39.16%] and 2% [41.57%] GSE in comparison with control [12.34%] [p 0.05]. The results also revealed that by increasing the amount of GSE, the TP and%SI were significantly increased. The results indicated that all characteristics of films were influenced by the extent of GSE. Improvement in antioxidant and total phenol of GSE assimilated films is appreciated. Such films are suitable for handle in preserving food
Subject(s)
Chitosan , Antioxidants , Oxidative StressABSTRACT
The film containing antimicrobial agents are a type of active packaging which is mainly designed to control microbial and chemical spoilage of food. The aim of this study was to evaluate the antimicrobial, antioxidant and color properties of chitosan film incorporated with essential oil of Zataria multiflora Boiss [ZEO]. In this experimental study which was conducted at Urmia University of Medical Sciences between 2009-2010, the chemical composition of ZEO was analyzed using GC-MS. Chitosan films containing 0, 0.5, 1 and 2% ZEO, were obtained by casting method and subsequently, total phenol [TP], antioxidant, color [accordance with hunter system [L*[luminosity], * [redness, and b* [yelloweness]] and antimicrobial characteristics of films on Listeria monocytogenes were studied. The collected data was analyzed by the SPSS software. The order of TP for all films in the experiment was 2% ZEO>1% ZEO%0.5% ZEO> unsupplemented chitosan film, respectively. It was also conducted that the antioxidant activity of chitosan films was increased by adding various concentrations of ZEO. These increases were significant for film containing 1% [33.98%] and 2% [37.77%] ZEO [p<0.05]. Regarding the color luminosity [L*] of the chitosan film, results indicated no significant changes by incorporating ZEO, whereas the incorporation of ZEO into films had a significant effect on film yellowness, evidenced by lower b* values. Finally, it was shown that the presence of ZEO in chitosan films significantly modified the anti-listerial activity of chitosan, [p<0.05]. The results indicated that an active film from chitosan could be achieved by incorporating ZEO. Addition of ZEO improves functional and antibacterial characteristics of chitosan film