Susceptibility of foodborne Pathogens and Spoilage Microorganisms to seed extracts of Citrullus Vulgaris and Citrus Reticulata

Abstract

Context: The importance of herbs in the management of food borne pathogens and spoilage organisms is of current interest since many plant components are bioactive and relatively safe when taken. Plant parts of Citrus reticulata and Citrullus vulgaris are used in herbal therapy in some parts of the world. Objective: The objective of this study was to evaluate the susceptibility of foodborne pathogens and spoilage microorganisms to seed extracts of Citrus reticulata and Citrullus vulgaris. Materials and Methods: The antimicrobial effect of ethanol and hot water extracts of C reticulata and C vulgaris seeds were studied using agar well diffusion technique. Minimum inhibitory concentration was performed using the modified tube dilution technique. The extracts were assayed on pure cultures of Bacillus subtilis, Staphylococcus aureus, Salmonella typhi, Escherichia coli, Saccharomyces cerevisiae and Aspergillus flavus. Results: Extracts tested at various concentrations produced in-vitro antimicrobial activities against foodborne isolates of B subtilis, S aureus, S typhi, E coli, S cerevisiae and A flavus.The highest zone of inhibition was obtained from ethanol extract at 4000µg/ml against B subtilis with diameter of 25mm for C reticulata. The lowest zone of inhibition of 10mm was obtained for E coli at 4000g/ml for the hot water extract of C vulgaris. The minimum inhibitory concentration (MIC) of the water extract of C reticulata and C vulgaris seeds ranged between 125-2000µg/ml. The MIC of the ethanol extract of the seeds of both plants was in the range 62.5-1000µg/ml.Comparatively, the ethanol extract of the seeds were more potent than the hot aqueous extract. The percent killing of the ethanol extract at 2000µg/ml was higher for C reticulata (45.6-100%) compared to that of C vulgaris (35.6-87.5). Conclusion:The results show that the ethanol extracts of Citrus reticulata and Citrullus vulgaris have potentential application for shelf life extension and as a pharmaceutical preparation.

A comparative study of polyherbal Unani formulations in gestational Urinary tract infections

“…The bicyclic sesquiterpene lactone isolated from the petroleum ether extract of the aerial part of Sphaeranthus was found to be potent against S. aureus, E. coli, Fusarium sp., Helminthosporium sp., and other microorganisms [14]. All parts (fruits, stems, leaves, and roots) of T. terrestris showed antibacterial activity against E. faecalis, S. aureus, E. coli, and P. aeruginosa [15] C. vulgaris exhibited antimicrobial potency against the test organisms such as Bacillus subtilis, S. aureus, E. coli, Salmonella typhimurium, Aspergillus flavus, and Saccharomyces cerevisiae [16]. The Acetone extract of C. melo L. shows highest antimicrobial activity against the bacteria E. coli [17].…”