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The chemical composition of essential oil obtained by hydrodistillation of the fresh aerial parts of Mentha requienii Bentham (Lamiaceae) collected on the Gennargentu Mountains (Sardinia, Italy) has been investigated by gas chromatography and gas chromatography-mass spectrometry. The main constituents that resulted were pulegone (78%), menthone (0.5%), isomenthone (18%), isopulegone (1.3%) and limonene (1.76%). In vitro antifungal activity is evaluated in order to identify new means that could be helpful in the prevention of contamination in indoor environments.

Aerial parts of wild Calamintha nepeta (L.) Savi subsp. nepeta growing spontaneously on the Mediterranean coast (Sardinia Island, Italy) and on the Atlantic coast (Portugal) were used as a matrix for the supercritical extraction of volatile oil with CO(2). The collected extracts were analysed by GC-FID and GC-MS methods and their compositions were compared with that of the essential oil isolated by hydrodistillation, but the differences were not relevant. A strong chemical variability was observed in the essential oils depending on the origin of the samples. The results showed the presence of two chemotypes of C. nepeta. In all Italian samples, pulegone, piperitenone oxide and piperitenone were the main components (64.4-39.9%; 2.5-19.1%; 6.4-7.7%); conversely, the oil extracted from Portuguese C. nepeta is predominantly composed of isomenthone (35.8-51.3%), 1,8-cineole (21.1-21.4%) and trans-isopulegone (7.8-6.0%). The minimal inhibitory concentration (MIC) and the minimal lethal concentration (MLC) were used to evaluate the antifungal activity of the oils against Candida albicans, Candida tropicalis, Candida krusei, Candida guillermondii, Candida parapsilosis, Cryptococcus neoformans, Trichophyton rubrum, Trichophyton mentagrophytes, Microsporum canis, Microsporum gypseum, Epidermophyton floccosum, Aspergillus niger, Aspergillus fumigatus and Aspergillus flavus. The Italian oil, rich in pulegone, exhibited significant antifungal activity against Aspergillus and dermatophyte strains, with MIC values of 0.32-1.25 µL mL(-1).

Nine samples of Glycyrrhiza glabra were collected in various sites of Calabria, Italy, with the aim to determine the variability in the confront of active constituents and in antibacterial and antifungal activities of the extracts. The samples showed remarkable differences in chemical composition and biological activity., (Copyright 2004 Elsevier B.V.)

Starting in 1999, seven experimental trials were carried out in Italy in order to evaluate the efficacy of chloropicrin (CP) (Tripicrin, a.i. 99% by wt) as alternative to methyl bromide for soil disinfestation. CP applied by shank injection at 30-40 g/m2 provided a satisfactory and consistent control of Fusarium wilt on melon and Verticillium wilt on eggplant, particularly in sandy soils. On melon against Fusarium wilt and on tomato against F. radicis lycopersici and Fusarium and Verticillium wilts CP at 40 or 60 g/m2 applied by drip irrigation at the concentration of 400 to 700 microliters/l or 850 microliters/l provided the best results. CP applied at 80 g/m2 with 60 mm of water (corresponding to 850 microliters/l) did not increase the efficacy of the soil fumigation treatment and, on tomato, was phytotoxic, causing sudden collapse of plants immediately after the transplant. The comparison of chloropicrin drip application under polyethylene, widely used in the past for methyl bromide soil fumigation, or under virtually gas impermeable film (VIF), to reduce atmosphere emissions, showed an increase of CP efficacy under VIF only reducing the dosages below 40 or 30 g/m2.

Soil was treated with olive mill waste water (OMW) in order to study the effect of this agriculture waste on soil fungal population. Changes in fungal composition were observed after soil pollution. In order to test OMW selective pressure, growth kinetics of Penicillium cyclopium, Scopulariopsis brevicaulis and Cladosporium cladosporioides were studied on solid media supplemented with different OMW concentrations. S. brevicaulis and C. cladosporioides did not grow at OMW concentration higher than 50%, while at concentrations lower than 50% a growth decrease was observed. Instead, P. cyclopium was able to actively grow at all concentrations of OMW tested. Therefore the OMW can influence and modify the soil fungal homeostasis.