Laccase belongs to a small group of enzymes called the blue multicopper oxidases, having the potential ability of oxidation. It belongs to enzymes, which have innate properties of reactive radical production, but its utilization in many fields has been ignored because of its unavailability in the commercial field. There are diverse sources of laccase producing organisms like bacteria, fungi and plants. In fungi, laccase is present in Ascomycetes, Deuteromycetes, Basidiomycetes and is particularly abundant in many white-rot fungi that degrade lignin. Laccases can degrade both phenolic and non-phenolic compounds. They also have the ability to detoxify a range of environmental pollutants. Due to their property to detoxify a range of pollutants, they have been used for several purposes in many industries including paper, pulp, textile and petrochemical industries. Some other application of laccase includes in food processing industry, medical and health care. Recently, laccase has found applications in other fields such as in the design of biosensors and nanotechnology. The present review provides an overview of biological functions of laccase, its mechanism of action, laccase mediator system, and various biotechnological applications of laccase obtained from endophytic fungi.

Six endophytic fungi were isolated from Cupressus torulosa D.Don and identified phenotypically and genotypically. The fungal cultures were further grown and the culture was extracted by two organic solvents methanol and ethyl acetate. The screening was carried out using the agar well diffusion method against human pathogen such as Escherichia coli, Salmonella typhimurium, Bacillus subtilis and Staphylococcus aureus. Isolated strain of Pestalotiopsis sp. was showing prominent antibacterial activity. The crude methanol and ethyl acetate extract of Pestalotiopsis sp. showed MIC of 6.25 mg/mL for S. typhimurium and S. aureus which showed its efficacy as a potent antimicrobial. The phytochemical screening revealed the existence of a diverse group of secondary metabolites in the crude extracts of the endophytic fungi that resembled those in the host plant extracts. On the basis of phenotypic characteristics and rDNA sequencing of the ITS region of the endophyte was identified as P. neglecta which turned out to be a promising source of bioactive compounds. There is little known about endophytes from C. torulosa D.Don. In this paper we studied in detail the identification of isolated endophytic fungi P. neglecta from C. torulosa D.Don and characterization of its active metabolite compounds. The partially purified second fraction (PPF) extracted from the fungal culture supernatant was subjected to gas chromatography followed by mass spectrometry which revealed the presence of many phytochemicals. These results indicate that endophytic fungi P. neglecta isolated from medicinal plants could be a potential source for bioactive compounds and may find potential use in pharmaceutical industry.

Despite the phytotoxicity of olive-mill solid waste (OMSW) due to its high polyphenols content, OMSW have fertilizer characteristics, which make it a potential source for organic fertilization. Composting of OMSW treatment process was conducted in this study to eliminate the phytotoxicity and solve the environmental impact of this waste. Recycling of OMSW was carried out via composting of six batches of trials using equal proportions of OMSW, cow manure (C) and wheat straw (W). The treatment process was performed at two time intervals (two and five months), after each one, the recipient species (Vicia faba L.) was planted. The results showed the efficiency of composting in reducing OMSW original toxicity after two months than five months. The germination percentage and the plumule and radicle lengths of V. faba showed a significant improvement when the OMSW was composted with C at different proportions before using as soil amendments. Besides, the total biomass was noticeably increased at the high concentration of C-OMSW. Similarly, the total pigments concentration in V. faba was increased by using various composts after two months, where the highest pigment content was observed at 40% W-OMSW treatment.

Plant growth promoting rhizobacteria (PGPR) are known to enhance growth of plants by involving various direct and indirect mechanisms. About sixteen rhizobacterial isolates were isolated from various rhizospheric soils of tomato crops in the fields of Dehradun. These bacterial isolates were phenotypically characterized and were subjected to in vitroscreeningfor their plant growth promoting traits like ammonia andsiderophore production,production of indole acetic acid (IAA), hydrogen cyanide (HCN) and phosphate solubilization.Out of sixteen bacterial isolate, three bacterial isolates proved to have potential PGPR activities. The production of indole acetic acid (IAA) by all rhizobacteria was investigated as possible mechanism for plant growth stimulation. All rhizobacterial isolates were shown to produce IAA in vitroin presences of L-tryptophan in the culture medium. The isolates were also tested for their efficacy in seed germination and seedling vigour by using tomato seeds in roll towel method.All rhizobacterial isolates also showed an increased in both the shoot and the root length of tomato seedlings as compared to the control. The seed germination ranged from 90 percent (uninoculated control) to 98.5 percent. All the three strains GKS-V, HPR-I, HPR-III significantly improved seed germination when compared to the uninoculated control (UIC). These isolate showed significantly increased in shoot and root length as well as enhanced vigour index of 124.54 and 741.45 after 6 and 16 days respectively. From biochemical tests it was concluded that all the three selected rhizobacteria belong to Pseudomonas species.

Biosphere is a store house of various microorganisms that may be employed to isolate and exploit microbes for environmental, pharmaceutical, agricultural and industrial applications. There is restricted data regarding the structure and dynamics of microbial communities in several ecosystems because only a little fraction of microbial diversity is accessible by culture methods. Owing to limitations of traditional enrichment methods and pure culture techniques, microbiological studies have offered a narrow portal for investigating microbial flora. The bacterial community represented by the morphological and nutritional criteria failed to provide a natural taxonomic order according to the evolutionary relationship. Genetic diversity among the isolates recovered from mushroom compost has not been widely studied. To understand genetic diversity and community composition of the mushroom compost microflora, different approaches are now followed by taxonomists, to characterize and identify isolates up to species level. Molecular microbial ecology is an emerging discipline of biology under molecular approach which can provide complex community profiles along with useful phylogenetic information. The genomic era has resulted in the development of new molecular tools and techniques for study of culturable microbial diversity including the DNA base ratio (mole% G + C), DNA–DNA hybridization, DNA microarray and reverse sample genome probing. In addition, non-culturable diversity of mushroom compost ecosystem can be characterized by employing various molecular tools which would be discussed in the present review.

Indole acetic acid (IAA) production is a major property of rhizosphere bacteria that plays a central role in plant growth and development as a regulator of cell division, cell differentiation, cell expansion, lateral root formation, flowering, and tropic responses. The present study deals with isolation, functional characterization and identification of IAA producing rhizobacteria from the rhizosphere. The present study deals with the emerging need to protect medicinal plants that represent our natural resources. A total ten bacterial isolates were recovered from rhizospheric soil associated with Withania somnifera, recognized as bacillus spp. by morphotpic and biochemical characterization and tested for indole acetic acid production. Out of ten rhizobacterial isolates, six were selected as efficient Producers of IAA. The amount of indole acetic acid produced was detected in the presence of different concentration of tryptophan, which lead to the elevation in indole acetic acid production as compared in the absence of tryptophan. The IAA production was further confirmed by thin layer chromatography (TLC). The impact of PGPR was evaluated on Withania somnifera seeds that showed significant elevation in germination %, root and shoot length as compared to the untreated seeds. Out of the chosen PGPR, WSNb3, WSNb5 and WSNb6 were showed to be the best to produce IAA. Subsequently, effect on plant growth was tested by towel paper assay. In conclusion the study suggests the IAA producing bacteria may be efficient biofertilizer inoculants to promote plant growth and protecting the medicinal plants for the future generation.

Among various man-made ecosystems, compost is an interesting example which presents a complete spectrum that harbor multitude of microbial diversity since it is a result of degradation of agro-residues. The microbial abundance, composition and activity change substantially during the composting process. The succession of microbial communities during composting is a classical example of how the growth and activity of one group of organisms can create conditions necessary for the growth of others. Several generations of microorganisms succeed each other during composting where microbial flora utilizes the available material in the substrate as also the cellular components of its predecessors for growth. Community structure and diversity are instrumental in manipulating compost environment in order to increase compost process and to improve compost quality.

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