Chemical Composition, Antimicrobial and Antioxidant Properties of Essential Oil of Origanum vulgar ssp. Gracile

BACKGROUND AND OBJECTIVE: Nowadays, in order to improve the health and reduce the risks of chemical preservatives in the food industry, researchers have focused on the use of natural compounds, especially plants essential oils that have antioxidant and antimicrobial properties, due to the increased risk of bacteria Escherichia coli and Listeria monocytogenes in foods, in this study the antimicrobial and antioxidant properties of Origanum vulgar ssp. Gracile essential oil were investigated in vitro. METHODS: In this experimental study, Origanum vulgar ssp. Gracile plant was prepared from Kurdistan and after drying and extraction of essential oils, components were identified using GC-MS device. Strains were prepared from the bacteriology laboratory of the Faculty of Veterinary Medicine, Tabriz University. In order to determine the minimum inhibitory and fatality concentration, various concentrations of extract were used (0.312, 0.625, 1.25, 2.5, 5 and 10 %), the minimum inhibitory and fatality concentration were determined using microdilution method. The antioxidant activity was performed by using the DPPH method and Total phenolic material was measured by Folin Ciocalteu reagent. FINDING: Based on the results of GC-MS analysis, carvacrol (49.33%) had the most component of the extract composition. The MIC and MBC of essential oils on Escherichia coli were 1.25 and 2.5%, respectively, and 0.625 and 1.25% for Listeria monocytogenes, respectively. In addition, the antioxidant activity 12.45±0.03 μg/ml, and the content of phenol 39.13±4.13 mg of gallic acid in grams of essence was calculated. CONCLUSION: The results of this study showed that Origanum vulgar ssp. Gracile essential oil had antioxidant properties, and the essence had an inhibitory effect on both bacteria and Listeria monocytogenesis was less resistant than Escherichia coli to the essential oil

Total phenolics, flavonoids content and antioxidant capacities of grape pomace fermented by Aspergillusoryzae

Antioxidants due to the extensive biological properties and their role in preventing of various diseases, are considered as components of health. Grape pomacevitisviniferacv.rish baba contains high amounts of antioxidant compounds. Fermentation of grape pomace by Aspergillusoryzae increases the extraction of these compounds. Ultrasound – assisted extraction is the most important methods for the extraction of valuable compounds from plant sources and accelerates the rate of extraction. The aim of this study was to evaluate of various factors effect on the extraction of phenolic compounds, flavonoids and antioxidant properties of grape pomace fermented by Aspergillusoryzae and using response surface methodology. The variables were temperature (55-67°c), time (24-32 min), solvent concentration (37-49%) and whey powder content (10-50gr). The highest rate of phenolic compounds and flavonoids were obtained at 64°c for 30 min and the solvent concentration of 46%. The highest level of DPPH and FRAP were obtained at 58°c for 30 min and the solvent concentration of 46%. With increasing extraction time phenolic compounds, flavonoids, DPPH and FRAP were ascending. Obtained results proved that fermentation by Aspergillusoryzae and using ultrasound – assisted extraction was a suitable method for the extraction of biological material from grape pomace with benefites such as high extraction rate, reducing the amount of solvent, temperature and time required