Effect of adding herb extracts as antimicrobial and antioxidant on the quality characteristics of some juices.

摘要

Antioxidant activity and inactivation pathogenic microorganism for extracts of sage, fennel, thyme, marjoram, chamomile and ginger as herb extracts were studied. Also, the effect adding of herb extracts on the antioxidant activity of mango, orange and carrot juices was also investigated. Results indicated that all herb extracts had different effect for the percentages of antioxidant activity ranged from 35.73 to 88.65%. Marjoram, thyme and sage had greatest antioxidant effect which was 88.65, 79.44 and 71.57%, respectively. Adding of thyme and marjoram extracts to juices recorded the highest effect of total antioxidant activity comparing with fennel and ginger extracts. The highest total phenolics content of thyme, marjoram and sage extracts was observed by adding to different juices while the fennel and ginger extracts recorded the lowest content. Results also showed that, antimicrobial activities in vitro the tested of herbs had affect for the potential activity of Stapylococcus aureus, Salmonella typhi and Escherichia coli and their activity potentials in inhibition zones as a result of presence of herb extracts. The results also showed that sage extract had greater potential antimicrobial agent against Salmonella typhi than other tested herb extracts. While, the highest inhibition zones against Stapylococcus aureus and Salmonella typhi was noticed in the presence of sage extract and the lowest inhibition was observed with ginger extract. On the other hand, the thyme and chamomile extracts had the highest inhibitions for Escherichia coli meanwhile; marjoram extract had the lowest effect for Escherichia coli inhibition.