Search

Background: The emergence of resistance to commonly used antibiotics by human infections occurred mostly due to their overuse, that prompted individuals to pursue novel and innovative treatments. The phytochemical characteristics, antibacterial activity, and cytotoxicity of MCF7 cells were evaluated in two Pleurotus spp. mycelial extracts in this work. Methods: Pleurotus djamor and Pleurotus florida mycelial extracts from pure cultures were tested for antibacterial activity by a well-diffusion assay and antimicrobial activity against mold fungi was evaluated for biomass inhibition. Mycelial extracts were obtained from dichloromethane extracts and their biophysical characteristics are analyzed by UV–vis spectrum and FTIR analysis. By spraying detection reagents onto TLC plates, the chemicals in dichloromethane extraction of chosen mushroom fungus mycelia were identified. Using the MTT test, the cytotoxic effect of dichloromethane extracts of selected mushroom fungi was evaluated on MCF7 Cell lines. Results: Mycelial extracts of P. djamor and P. florida exhibited significant antimicrobial effect on the bacterial and fungal pathogens tested. Dichloromethane mycelial extracts were obtained using soxhlet extraction which response positive for various phytochemical analysis. Detection of metabolites in thin layer chromatography using spray reagents documented one of few first accounts on flavonoids, anthroquinone and terpenoid compounds in P. djamor and P. florida. P. djamor and P. florida had dose-dependent antiproliferative activity against MCF7 cells, with an inhibitory impact of 55.72% and 64.47% percent at 125 μg/mL, respectively. Conclusion: The study has reported the identification with the potent biological activity of some of the key bioactive components present in DCM extracts from the mycelia of P. djamor and P. florida.

We assessed the differential response of Azolla microphylla and Azolla filiculoides to fluoride stress by growing them in culture media containing 1 to 50 ppm sodium fluoride (NaF). A microphylla had a higher total chlorophyll content than A. filiculoides. Both species showed gradual decreases in protein content as the concentration of NaF increased. A. microphylla accumulated less proline than A. filiculoides when more NaF was added to the culture medium. For all concentrations tested, the amount of residual fluoride in the nutrient media that supported A. microphylla was higher than in the nutrient media used for growing A. filiculoides. [ABSTRACT FROM AUTHOR]

Melanins are enigmatic pigments produced by a wide variety of microorganisms including bacteria and fungi. Here, we have isolated and characterized extracellular melanin from mushroom fungus, Schizophyllum commune. The extracellular dark pigment produced by the broth culture of S. commune, after 21 days of incubation was recovered by hot acid-alkali treatment. The melanin nature of the pigment was characterized by biochemical tests and further, confirmed by UV, IR, EPR, NMR and MALDI-TOF Mass Spectra. Extracellular melanin, at 100 μg/ml, showed significant antibacterial activity against Escherichia coli, Bacillus subtilis, Klebsiella pneumoniae and Pseudomonas fluorescens and antifungal activity against Trichophyton simii and T. rubrum. At a concentration of 50 μg/ml, melanin showed high free radical scavenging activity of DPPH (2,2-diphenyl-1-picrylhydrazyl) indicating its antioxidant potential. It showed concentration dependent inhibition of cell proliferation of Human Epidermoid Larynx Carcinoma Cell Line (HEP-2). This study has demonstrated characterization of melanin from basidiomycetes mushroom fungus, Schizophyllum commune and its applications.

Considering the industrial interest of Poly-beta-hydroxybutyrate (PHB), bacteria isolated from the various marine arenas were screened for their ability to accumulate PHB and were compared with Wausteria eutropha (MTCC-1285). Among the 42 isolates, four strains showed the accumulation of PHB. The maximum PHB producer Vibrio sp. (MK4) was further studied in detail. To increase the productivity, steps were taken to evaluate the effect of carbon sources, nitrogen sources, pH and sodium chloride concentration on PHB productivity by MK4. The optimized conditions were further used for the batch fermentation over a period of 72 h. Significantly higher maximum biomass of 9.1g/L with a PHB content of 4.223 g/L was obtained in a laboratory-scale bioreactor at 64 h, thus giving a productivity of 0.065 g/L/h. The extracted polymer was compared with the authentic PHB and was confirmed to be PHB using FTIR analysis and (1)H NMR analysis. Thus, the study highlights the potential of the use of Vibrio sp (MK4) in the commercial production of PHB.

Inter-specific hybridization between Pleurotus pulmonarius and P. florida was attempted through PEG-induced protoplast fusion to select a fusant. The protocol for protoplast release, regeneration and fusion in these two Pleurotus species was standardized using the variables controlling the process. The mixture of mycolytic enzymes, i.e. commercial cellulase, crude chitinase and pectinase, KCl (0.6 M) as osmotic stabilizer, pH 6 of the phosphate buffer and an incubation time of 3 hours resulted in the maximum release of protoplasts from 3-day-old mycelia of P. florida (5.3~5.75 × 10(7) protoplasts/g) and P. pulmonarius (5.6~6 × 10(7) protoplasts/g). The isolated protoplasts of P. florida regenerated mycelium with 3.3% regeneration efficiency while P. pulmonarius showed 4.1% efficiency of regeneration. Polyethyleneglycol (PEG) - induced fusion of protoplasts of these two species resulted in 0.28% fusion frequency. The fusant produced fruiting bodies on paddy straw but required a lower temperature of crop running (24 ± 2℃) than its parents which could fruit at 28 ± 2℃. The stable fusant strain was selected by testing for the selected biochemical markers i.e. Carbendazim tolerance and utilization of the lignin degradation product, vanillin.