0099-2240/86/051085-04$02.00/0 Copyright C) 1986, American Society for Microbiology
Vol. 51, No. 5
New Source of Natural Fungitoxicantt
ANUPAM DIKSHIT,* ALI A. NAQVI, AND AKHTAR HUSAIN Central Institute of Medicinal and Aromatic Plants, Lucknow-226016, India
Received 12 February 1986/Accepted 21February 1986
The oil of Schinus moUe exhibited the maximum fungitoxic activity during the screening of some essential oils against some common storage and animal pathogenic fungi. It showed absolute toxicity against animal pathogens and mild activity against storage fungi. The effective concentrations of the oil varied from 200 to 900 ppm. The toxicity of the oil persisted up to 80°C and 90 daysof storage but declined when autoclaved. It withstood heavy inoculum density. The oil exhibited a narrow range of activity and was found to be more effective than Multifungin, an antifungal drug. The oil was characterized by its various physicochemical properties. It was found to comprise 50 constituents. It appeared that some changes in the oil constituents during storage affected its fungitoxicpotency.
Naturally occurring fungitoxicants described to date are mostly biodegradable (3) and are devoid of side effects (9) compared with commerically available fungitoxicants. We report here results of our investigation of Schinus molle L., a member of the Anacardiaceae, as a new source of fungitoxicant. Essential oils extracted from higher plants were investigated for their fungitoxicactivity; test fungi used were those which caused dermatomycoses in animals and fungal deterioration of foodstuffs during storage.
MATERIALS AND METHODS
Essential oils were extracted from different parts of 10 taxa of phanerogams by hydrodistillation with a Clevenger apparatus (4) and were evaluated at various concentrations
and storage fungi such as Alternaria alternata (Fries) Keissler,Aspergillus flavus Link, and Penicillium italicum Wehmer. The evaluations were performed by using the "'poisoned food" technique (7) with Sabouraud dextrose agar medium. Minimum fungistatic and fungicidal concentrations of the oils were evaluated by the method of Garber and Houston (10). The influence of temperature, storage, and inoculum density on the mycelial growth inhibition (MGI) of the oils at500 ppm were observed as previously described by Dikshit and Dixit (6). A total of 19 animal or phytopathogenic fungi were used to test the MGI of S. molle oil (500 ppm) by the conventionally used poisoned food technique. The fungistatic-fungicidal
TABLE 1. Inhibition of animal pathogenic and storage fungi by essential oils from higher plants MGI (%) against: Animal pathogenic fungia Storagefungib Oil source Family Species
Apiaceae Apium graveolens L. (celery) Lauraceae Cinnamomum cecidodaphne Meissn. (Sugandh Kokila) Leaves Lamiaceae Elsholtzia polystachya Benth. (Bhangaria) Leaves Cupressaceae Juniperus communis L. (juniper) Leaves Lamiaceae Lavandula officinalis Chaix (lavender) Aerial parts Lamiaceae Mentha arvensis L. (Japanese mint) Fruit ApiaceaePleurospermum angelicoides (D.C.) Kl. (Moor) Aerial parts Lamiaceae Salvia sclarea L. (clarysage) Leaves AnacardiaSchinus molle L. (California pepper ceae tree) Seed Rutaceae Zanthoxylum alatum Roxb. (Tomer) Mg, M. gypseum; Tm, T. mentagrophytes; Tr, T. rubrum; tested at 400 ppm. b Aa, A. alternata; Af, A. flavus; Pi, P. italicum; tested at 500 ppm.
66.6 48.128.3 69.5 40.0
31.8 47.8 60.0 53.3 21.7
54.5 48.4 24.5 64.2 55.8
65.2 58.8 58.8 53.5 58.8
62.0 80.0 74.0
52.3 53.5 57.1
for fungitoxic activity against common animal pathogenic...