Production, purification and characterisation of a black pigment from Termitomyces albuminosus as melanin is reported, for the first time, from shaken submerged culture condition using scanning electron microscopy (SEM), elemental analysis, ultraviolet–visible (UV-VIS), and Fourier transformed infrared spectroscopy (FTIR), electron paramagnetic resonance (EPR) and 13C (CP/MAS) NMR spectra. SEM results on T. albuminosus revealed nanogranular nature of melanin nanoparticles within size range of 400–100 nm with fractal dimension D = 1.195–1.73. Elemental analysis of melanin indicated 54.6% C, 3.5% H, 2.4% N, 26.9% O, and 12% S. UV-VIS and FTIR spectra confirmed to the characteristic of melanin and were identical to the reference commercial sepia melanin. Further validation of the identity of pigment as melanin was achieved by EPR analysis. Termitomyces albuminosus melanin is postulated to be DOPA-type melanin confirmed by 13C (CP/MAS) NMR spectral analysis showing chemical shift at 200–170 ppm carbonyl, 160–110 ppm aromatic region, and with high 40–30 ppm open chain aliphatic region. Chemical modification through oxidation and cysteinylation (Pheomelanin) is implied as indicated by relatively high sulphur content (12%).

Out of the 30 actinobacterial cultures screened for antimicrobial activity, 28 cultures were found to produce active products against various pathogenic microorganisms such as Gram-negative, Gram-positive bacteria and yeast, using a modified cross streak method. The modified method helped in easy quantification of results and also in ruling out probable mutual antibiosis. The actinobacterial strains that showed the ability to produce antimicrobial compounds belonged to Streptomyces (53%), Micromonospora (13%) and Actinomadura (10%) genera. Streptomyces sp. strain MMA-5 showed the highest multispecific antibiosis efficiency score value. Broad antibiotic spectrum activity was exhibited by Streptomyces sp. strain MMA-2 and Micromonospora sp. strain MMA-8. The multidrug resistant human pathogenic yeast strain Candida albicans was inhibited by 18 actinobacterial strains.

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There is considerable interest in identifying wild tropical strains of oyster mushrooms useful for cultivation, strain improvement and systematic breeding programme. During routine surveys to identify such strains from Goa's western ghats an interesting wild form of Pleurotus ostreatus was found growing on logs of wild Mangiferra indica L a novel habitat for the species reported for the first time. After obtaining and screening several pure isolates, a fertile strain BA-50/GUOMS was selected for cultivation under natural outdoor conditions. Spawn prepared on wheat grains was produced within 11 days and was used to ramify sterilized paddy straw as substrate using standard polybag technique. Spawn run was initially slow and took 52 days. Mushrooms fruitbodies identical to the original wild type were produced in eight flushes at intervals of 8 to 13 days for each flush over a period of four months. These had pleasant odour, better shelf life, tougher texture, resistance to insects, fungi and bacteria, exhibited photosensitivity by producing brownish pigment in direct sunlight and responded well to outdoor conditions for fruit body initiation with ambient temperature ranging from 23-35 o C.

New molecule discovery from natural sources, such as that of actinobacteria, has proved to be an interesting area in antibiotic research, as most of these antibiotics are difficult to synthesize. Out of 30 actinobacterial cultures screened for antimicrobial activity, 28 cultures were found to produce active products against various pathogenic microorganisms such as Gram-negative, Gram-positive bacteria and yeast, using a ‘modified cross streak method.' The modified method helped in easy quantification of results and also in ruling out probable mutual antibiosis. 53%, 13% and 10% of tested actinobacterial strains belonging to Streptomyces, Micromonospora and Actinomadura genera, respectively, showed the ability of producing antimicrobial compounds. Streptomyces sp. strain MMA-5 showed the highest percentage multispecific antibiosis efficiency score value. Broad antibiotic spectrum activity was exhibited by Streptomyces sp. strain MMA-2 and Micromonospora sp. strain MMA-8. The multidrug resistant human pathogenic yeast strain Candida albicans was inhibited by 18 actinobacterial strains.