In vitro evaluation of antimicrobial effect of walnut and celery extracts

The greatest majority of deteriorations of food product originates from microorganisms. Microbial control has a vital importance for food industry, because of its possible effects on both processed foods and raw materials. Inhibition of microorganisms is essential for food safety and food security. Ever since ancient times to nowadays, antimicrobial agents have been using to control of microorganisms. Antimicrobial agents might be obtained from natural sources or produced by synthetically. However, utilization of synthetic antimicrobial agents to preserve food products have been seriously debated of late years, by reason of increasing awareness to health and environmental matters. At the same time, antimicrobial resistance which has been described as world-wide significant trouble has provided basis to search of novel, natural antimicrobial agents. Essential oils and plant extracts are important groups among natural antimicrobial agents. In this study, antimicrobial effects of celery leaves and stems and walnut husk extracts have been evaluated in vitro conditions. Celery stems and leaves, walnut green husks have been utilized as extraction materials. Plant extracts have obtained by using methanol and metahanol/water (50:50, v/v) solvents through method of ultrasound assisted solvent extraction. Disk diffusion and micro dilution methods have been used for determination antimicrobial activity of plant extracts and hydrosols against Escherichia coli ATTC 25922, Staphylococcus aureus ATTC 25923 bacteria and Candida albicans ATCC 10231, Candida albicans ATCC 36802, Candida krusei KUEN 1001 ve Candida krusei 6258. The highest antimicrobial activities have been seen at the extracts of the green walnut husk and the celery methanol-water extracts. These plant extracts showed impacts in different levels on bacterial and yeast strains as result of both method.