Chemical composition, antifungal and antioxidant activity of Pelargonium graveolens essential oil.

The present study describes the chemical composition, antifungal and antioxidant activity of Pelargonium graveolens essential oil. The essential oil profile was determined by GC and GC-MS. The main compounds were citronellol (24.54%), geraniol (15.33%), citronellyl formate (10.66%) and linalool (9.80%). Minimal inhibitory concentrations (MIC) and minimal fungicidal concentrations (MFC) were recorded using the microdilution and macrodilution methods. Commercial antimycotic bifonazol was used as a control. The concentration of 0.25-2.5 mg/ml showed fungicidal activity. The most resistant fungi were Mucor mucedo and Aspergillus species. The antioxidant activity of pure essential oil was evaluated by means of the 2,2-diphenyl-1-picrylhydrazil (DPPH) radical assay. The essential oil of P. graveolens was able to reduce DPPH radicals into the natural DPPH-H form, and this activity was dose-dependent. The oil exhibited antioxidant activity and reduced DPPH to 50% at EC50 value of 0.802 mg/ml of oil solution.

Total phenolic and flavonoid content, antioxidant and antimicrobial activity of extracts from Tordylium maximum.

The present study describes the total phenolic and flavonoid content and in vitro antioxidant and antimicrobial activity of methanol and water extracts from Tordylium maximum L. wild growing in Serbia. The total phenolic content in the extracts was determined using Folin-Ciocalteu reagent and their amounts ranged between 74.59 to 83.36 mg GA (gallic acid)/g. The concentrations of flavonoids in the extracts varied from 20.48 to 47.71 mg Qu (quercetin)/g. Antioxidant activity was analyzed using DPPH reagent. Antioxidant activity ranged from 4.042 to 7.825 IC50 (mg/ml) and from 2.48 to 2.78 mg VitC (vitamin C)/g when tested with the DPPH and ABTS reagents, respectively, using BHA and VitC as controls. The antimicrobial activity of the extracts was investigated using a micro-well dilution assay against the most common human gastrointestinal pathogenic bacterial strains: Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 9027, Salmonella enteritidis ATCC 13076, Bacillus cereus ATCC 10876, Listeria monocytogenes ATCC15313, Staphylococcus aureus ATCC 25923 and Candida albicans ATCC 10231. This finding suggests that T. maximum may be considered as a natural source of antioxidants and antimicrobial agents.