~ 102 ~ International Journal of Herbal Medicine 2017; 5(2): 102-106 E-ISSN: 2321-2187 P-ISSN: 2394-0514 IJHM 2017; 5(2): 102-106 Received: 20-01-2017 Accepted: 21-02-2017 Maryam Khosravinezhad Shiraz Branch, Islamic Azad University, Shiraz, Fars, Iran Ebrahim Talebi Darab Branch, Islamic Azad University, Darab, Fars, IRAN Shivakumar Central Sericultural Research and Training Institute, Central Silk Board, Pampore, Jammu & Kashmir, 192121, India Zahra Nemati Shiraz Branch, Islamic Azad University, Shiraz, Fars, Iran Iman Nasrollahi Darab Branch, Islamic Azad University, Darab, Fars, IRAN Correspondence Maryam Khosravinezhad Shiraz Branch, Islamic Azad University, Shiraz, Fars, Iran Essential oil composition and antimicrobial, antioxidant activities of Oliveria decumbens Vent Abstract A scientific experiment was conducted by utilizing herbal essential oil plants of Oliveria decumbens Vent by subjecting to extraction of essential oil through the standard microwave assisted hydro distillation (MAHD) method. The chemical composition of the essential oil detected with GC/MS technique. The obtained results clearly quantified main components oil like, m-thymol (34.80%), thymol (34.36%), myristicin (20.88%), etc. Further, antimicrobial activity of Oliveria decumbens Vent oil was noticed, which clearly showed on gram-positive and gram-negative effects respectively and some of the fungal species too. However, antibacterial activity against gram positive bacteria, Staphylococcus aureus was respected MIC=8 and antifungal activity against alternaria fungus was MIC=16 clearly noticed. Morever, antioxidant activity was determined with DPPH oil through which obtained results was antioxidant activity of oil (IC50 = 2.73 ± 0.172) recorded. Apart, total phenol reagent with Folin–Ciocalteu and gallic acid was determined with the standard curve and obtained results of total phenol of IC50 = 0.072 ±0.027 value was clearly evident. Keywords: Oliveria decumbens Vent, GC/MS, antimicrobial, antioxidant. 1. Introduction The popular “umbelliferae” family is one of the biggest and popularly known as vegetable’s family that have been distributed in all over the world. In addition to that, most of the plants belonging to this family produce terpenes and other types of volatile compounds. Many researches have been executed about antibacterial and preservative effects of herbal essential oils [1, 2] . Oliveria decumbens Vent belongs to Apiaceae family is an endemic plant of flora iranica that grows in high temperature areas of south and west of Iran [3] .This plant have been calling since back several years with the different common Persian names are “Mooshkorok”, “Den”, and “Denak” [4] etc. In the background of traditionally known medicines, it is used for several purposes like, Indigestion, Diarrhea, Abdominal pain, Fever [5] , etc. But currently, shift to different dimension, in regard to much research performed on antimicrobial compounds from plant extracts and essential oils, the goal being to identify novel lead structures with significant biological activities [6] . Moreover, the most important of these bioactive constituents of plants are alkaloids, tannins, flavonoids, and phenolic compounds [7] . Numerous studies have shown that aromatic and medicinal plants are sources of diverse nutrient and no nnutrient molecules, many of which display antioxidant and antimicrobial properties which can protect the human body against both cellular oxidation reactions and pathogens. Thus, it is important to characterize different types of medicinal plants for their antioxidant and antimicrobial potential [8-10] . Hence, keeping the above concept in mind, the prime focus of this research experiment was to understand the antioxidant and antimicrobial properties of Oliveria decumbens Vent. 2. Materials and methods 2.1 Chemicals Folin–Ciocalteu, sodium carbonate methanol, 2, 2-diphenyl-1-picrylhydrazyl (DPPH), quercetin, gallic acid and over all the total chemicals were purchased from the Merck Germany. 2.2 Plant material All parts of the plant of O. decumbens Vent were collected during May 2015 from Southern Iran (Bandar Abbas). The all parts of the plant were kept at room temperature (25 °C) and dried under the shade area of the standard laboratory condition and plant samples were identified in the medicinal herbs Research Center of Bandar Abbas. Maryam Khosravinezhad, Ebrahim Talebi, Shivkumar, Zahra Nemati and Iman Nasrollahi