Contribuţii Botanice – 2013, XLVIII: 75-82 Grădina Botanică “Alexandru Borza” Cluj-Napoca THE ANTIFUNGAL ACTIVITY OF ALLIUM SCHOENOPRASUM L. LEAVES Marcel PÂRVU 1 , Ioana RUSU 1 , Oana ROŞCA-CASIAN 2 1. Babeş-Bolyai University, Faculty of Biology and Geology, 42, Republicii Street, RO-400015 Cluj-Napoca, Romania 2. Babeş-Bolyai University, „A. Borza” Botanical Garden, 42, Republicii Street, RO-400015 Cluj-Napoca, Romania e-mail: mparvucluj@yahoo.com Abstract: The antifungal activity of Allium schoenoprasum (chives) leaf extract was tested in vitro against the following phytopathogenic fungi: Aspergillus niger, Botrytis cinerea, B. paeoniae, Fusarium oxysporum f. sp. tulipae, Penicillium gladioli, and Sclerotinia sclerotiorum. The minimum inhibitory concentration (MIC) was 70– 120 μl/ml, depending on the fungal species. The results were compared to those obtained for Fluconazole (MIC = 80–300 μl/ml) and synthetic allicin (MIC = 100–160 μl/ml). Key words: Allium schoenoprasum, antifungal activity, allicin, in vitro, MIC, phytopathogenic fungi Introduction The active trend in plant protection is finding different sources of natural compounds with antimicrobial activity, which can successfully replace the products obtained by chemical synthesis. Therefore, the study of chemical compounds derived from plants is seen as a good source of bioactive molecules. The bioactive fungicides, for example, have proved to be efficient against specific pathogens, while at the same time being biodegradable. The best alternative method for the control of phytopathogens is provided by the variety of constituents found in medicinal plants. One of the most renowned groups of these plants, used since ancient times for their therapeutic properties, is represented by species of Allium. There is plentiful information in the literature regarding the phytotherapeutic properties of the species Allium cepa (onion) and A. sativum (garlic) [2, 6, 10, 20, 26, 27, 53, 55]. These Allium species have been shown to have mainly antimicrobial activities – antifungal [5, 17, 28, 31, 32, 49, 61] and antibacterial [11, 22, 57] – but also anti-oxidant [7, 9, 50, 52, 60], anti-inflammatory [19, 30, 46], and anti-hypertension properties [3, 4, 15]. There is also information on their anti-allergic [21], anti-diabetic [40], hepato-protective [36], and neuro- protective [18] properties. Allium includes over 200 components such as volatile oils (allicin, alliin and ajoene) containing sulphur, enzymes (alliinase, peroxidase and miracynase), carbohydrates (sucrose, glucose), minerals (germanium, selenium, zinc), amino acids such as cysteine, glutamine, isoleucine and methionine, bioflavonoids such as quercetin, cyanidin and allistatin I and allistatin II, vitamins C, E and A and niacin, vitamins B 1 , B 2 and beta carotene [13]. Allium-derived antimicrobial compounds inhibit micro-organisms by reacting with the sulfhydryl (SH) groups of cellular proteins. It used to be thought that allicin reacts only with cysteine and not with non-SH