The effect of Lamiaceae plants essential oils on fungal plant pathogens in vitro

S. Lukošiūtė*, L. Šernaitė, A. Morkeliūnė, N. Rasiukevičiūtė and A. Valiuškaitė

Lithuanian Research Centre for Agriculture and Forestry, Institute of Horticulture, Laboratory of Plant Protection, Kaunas Str. 30, LT-54333 Babtai, Kaunas dist., Lithuania

Abstract:

Fungal pathogens Alternaria spp., Botrytis spp. and Colletotrichum spp. cause a significant loss of horticultural crops and their yield annually. The most convenient way for controlling diseases caused by these pathogens is the use of chemical fungicides. However, current practices still result in soil, water and air pollution, contribute to the loss of biodiversity and climate change, also are harmful to human health. Therefore, there is a growing demand for environmentally friendly plant protection methods. Herbs, especially, volatile oils, are a natural source of active ingredients. The findings of antimicrobial and antifungal activities, low toxicity, and biodegradability of essential oils make them potential for use in plant protection against pathogens instead of chemicals. This research aimed to evaluate the ability of Lamiaceae plants essential oils to suppress the growth of Alternaria spp., Botrytis spp., and Colletotrichum spp. in vitro. The study was carried out at the LAMMC Institute of Horticulture, Lithuania. Essential oils from lavender (Lavandula angustifolia) and thyme (Thymus vulgaris) were obtained by hydrodistillation and poured to potato dextrose agar medium at 200–1,000 μL L-1 concentrations. The radial colony growth of each pathogen measured after placing mycelial plugs of each fungus on Petri dishes. Results demonstrated that thyme essential oil significantly suppressed the growth of all three investigated fungal pathogens at concentrations starting from 400 μL L-1 7 days after inoculation as no growth of the pathogens observed. Meanwhile, lavender essential oil had lower antifungal activity than thyme. The most significant concentration of lavender essential oil was 1,000 μL L-1. To conclude, thyme essential oil showed high antifungal activity, and lavender essential oil showed moderate antifungal activity for our tested horticultural crop fungal pathogens. Both oils can be applied as one of the eco-friendly ways to control plant pathogens

Key words:

antifungal, inhibition, Lavandula angustifolia, lavender, thyme, Thymus vulgaris

Partial Purification of β–glucosidase enzyme from soybean (Glycine max) and determination of inhibitory effects two quercetin derivatives on enzyme activity

A.C. Olcay, G. Bilir, Ö. Taş, M. Deniz and D. Ekinci*

Ondokuz Mayıs University, Faculty of Agriculture, Department of Agricultural Biotechnology, TR 55139 Samsun, Turkey; e-mail: deniz.ekinci@omu.edu.tr

Abstract:

Glucosidases are enzymes that catalyze the hydrolysis of the glycosidic linkage of glycosides, leading to the formation of a sugar hemiacetal or hemiketal and the corresponding free aglycon. Activity of glucosidases is crucial for several biochemical processes. Thus, discovery of new glucosidase inhibitors is crucially important owing to potential therapeutic applications of this enzyme in the treatment of diabetes, human immunodeficiency virus infection, metastatic cancer, lysosomal storage disease etc. In the current study, inhibitory potential of ‘quercetin’ and its isomeric form ’morin hydrate’ on the activity of β-glucosidase enzyme, present in the extract of soybean (Glycine max L.) seeds, were investigated. The compounds exhibited moderate inhibitory action in low milimolar concentrations. I50 values were calculated as 0.188 and 0.138 mM for quercetin and morin hydrate, respectively. The results have confirmed that these compounds can be used as leads for designations of novel glucosidase inhibitors which would be used in medicinal biotechnology and food science and technology.

Key words: