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The purpose of the present study was to prepare ethanol extract of Portulaca oleracea L. leaves (PLE) that is rich in phenolic compounds and investigate there in vitro and in vivo antioxidative activities using ethanol to induce oxidative stress in the liver. This study includes two phases. The first phase includes assessment of antioxidant capacity in vitro using 1,1- Diphenyl-2-picrylhydrazyl (DPPH) assay and 2,2-azinobis-(3-ethyl-benzothiazo-line-6-sulfonic acid) (ABTS) assay. In the second phase (assessment of antioxidant capacity in vivo), the levels of antioxidant parameters in the alcoholic liver disease rats were studied and the protective effect of ethanolic extract of P. oleracea L. in the alcoholic liver disease rats was examined to further understand their mechanisms. In vitro studies with DPPH and ABTS showed that PLE possesses antioxidant activity. In vivo administration of ethanol (7.9 g/kg body weight/day) for 45 days with PLE (100 mg/kg body weight/day) signii¬cantly decreased the activities of liver markers enzyme serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) and gamma glutamyl transferase in serum towards near normal level. In addition, PLE also signii¬cantly reduced the levels of lipid peroxidation and in addition, signii¬cantly restored the enzymatic and non-enzymatic antioxidants level in the liver of alcohol administration rats. Our study suggests that ethanol extract of P. oleracea leaves play a benei¬cial role in the treatment of alcohol induced tissue damage, which could be one of its therapeutic values. Key words: Alcoholic liver disease, Portulaca oleracea L., oxidative stress, ethanolic extract, antioxidants, rats.

Article history: In this study, we evaluated the antibacterial activity of hydrolysates from lupin protein in vitro against gram positive (Staphylococcus aureus and Bacillus subtilis) and gram negative (Pseudomonas aeruginosa and Escherichia coli) bacteria and in food system (in minced beef under refrigerated condition).Hydrolysis of lupin protein with Alcalase was monitored for 4 h. Hydrolysates obtained after 1, 2, 3 and 4h had degree of hydrolysis values of 9%, 16%, 23% and 25%, respectively. The minimal inhibitory concentration (MIC) of LPH was determined against all bacterial strains. MIC value of LPH against all bacterial strains was 100 µg ml -1 . The results showed that gram positive bacteria were more sensitive than gram negative bacteria. Adding LPH at different concentrations (100, 150 and 200 µg/g) to minced beef showed antibacterial activity during storage at 4°C compared to nisin (200 µg/g) as a positive control. The results of this study showed that enzymatic hydrolysis by Alcalase at pH 7.8 and 55 °C for 240 min is an easy tool to increase the antibacterial activity of lupin protein against both gram negative and gram positive bacteria and can be used as a bio-preservative in food system. Extending the technological validity of minced beef will help avoid big losses of minced beef and enhance its chances to be incorporated into many meat products while avoiding hygienic, chemical and technological deterioration.