Enrichment and isolation of microbial strains degrading bioplastic polyvinyl alcohol and time course study of their degradation potential

Polyvinyl alcohol (PVA) degrading bacterial strains were isolated from various environmental sites richin plastic wastes by using the enrichment culture technique. Among the various isolated strains, theselected potent PVA degrading bacterial strains were tentatively characterized as Bacillus and Pseudomonas sp. The time course of the PVA degradation potential of the characterized strains in growth media containing PVA as a major carbon source was evaluated using the spectropho-tometric assay method. This was done by determining the residual PVA remaining in the culture media, increase in cell growth and change in pH of the media over a period of twenty days. The ultimate biodegradation (mineralization) of PVA to its mineral constituents CO2 and H2O was determined by the CO2 evolution test. The strain characterized as Bacillus sp. showed 65% of PVA degradation as determined by spectrophotometric assay and 45.4% of mineralization of PVA over a period of 20 days. The strain characterized as Pseudomonas sp. showed 42% of PVA degradation as determined by spectrophotometric assay and 28.9% of mineralization of PVA over a period of 20 days.Key words: Polyvinyl alcohol (PVA) degrading bacteria, isolation, ultimate biodegradation, mineralization

An overview of intellectual property rights in relation to agricultural biotechnology

The majority of the population in developing nations depends on agriculture. Agricultural biotechnology involves genetic modification and promises a number of important benefits, such as improving agricultural yields by increasing the resistance of crops to pests and facilitating them to flourish in harsh natural environments, improving the productivity of crops, and reducing pesticide use. Also, concerns have been raised about the potential negative impacts of genetic modification. To promote research and development in agricultural biotechnology, intellectual property rights (IPRs) are one of the primary tools. Based on the fact that high investment is required to develop new genetically modified (GM) technologies and products, stronger intellectual property protection is necessary to stimulate research and to allow recovery of investment. As international rules increasingly raise the level of intellectual property protection, there is rising concern about the potential negative impacts on the dissemination of knowledge and important products, further Research and Development, food security, and the conservation of biodiversity among other fundamental areas of public policy. It is thus an important policy challenge to determine application of laws, rules and legislations to agricultural biotechnology. IPRs are woven into innovations, enable entrepreneurship and they allow the leveraging of private resources for resolving the problems of hunger and poverty.Keywords: Biotechnology, intellectual property rights, patents, genetic modificatio

Interaction of Mycobiont: Piriformospora Indica with Medicinal plants and plants of Economic importance

Traditional medicines of plant origin are used by world’s large population. Economic development including eradication of poverty in developing countries like, India or other countries of the world required increase in agricultural productivity. Bio fertilizers plays a very important role in modern agriculture, in achieving higher productions in Agriculture at lower input costs using biotechnological innovations at large. An endophytic symbiotic fungus, Piriformospora indica isolated from desert soils of Rajasthan, India promotes growth as well as important ingredients of the medicinal as well as economically important plants by forming association with roots of various plants and it has been established as biofertilizer, bioprotector, immunoregulator and agent for biological hardening of tissue culture raised plants. P. indica tremendously improves the growth and overall biomass production of adiverse host including legumes, medicinal and economically important plants. Pronounced growth promotional effect was seen with terrestrial orchids. P. indica was able to colonize the rhizoids of liverwort and the thalli failed to grow under in situ conditions in the absence of this fungus. The fungus also provided protection when inoculated into the tissue culture raised plants by overcoming the ‘transient transplant shock’ on transfer to the field and renders almost 100% survival on transplant. P. indica cell biomass which has potential for promoting growth of many plants (above 145) has been documented so far which include plants such as Centella asiatica, Coriandrum sativum, Artimisia annua, Spilanthus calva, Arabidopsis thalina, Cajanus cajan, Arachis hypogea, Mimosa pudica, Cicer arietinum, Allium cepa, Hordeum vulgare, Zea mays, Saccharum officinarum, Withania somnifera, Solanum lysopersicum, etc. However, impact of P. indica culture filtrate on plant growth promotion has been studied only in few plants. Important medicinal plants and plants of economic importance on which effect of culture filtrate of P. indica has been studied include plants such as Z. mays, Bacopa monniera, Nicotiana tabaccum, Azadiracta indica, Aristolochia elegans, Helianthus annus and Solanum melongena. P. indica, a root colonizing fungus which is cultivable axenically, uniquely possesses multifunctional properties such as plant promoter, plant protector, resistance against heavy metals, bio herbicide, immune-modulator, resistance against temperature, salt and stress tolerance as bio fertilizer and tool for basic research. There are prospects that ingredients present in culture filtrate, that are stimulated and produced in response to ingredients of culture filtrate in plants, will be identified in future completely thereby opening more avenues of applications of P. indica. Many more properties and functions of P. indica cells and culture filtrate are expected to be known in future.Keywords: Helianthus annus, Piriformospora indica, seed oil content, culture filtrate, aristolochia, plant microbe interactio

Production of a potential liquid plant bio-stimulant by immobilized Piriformospora indica in repeated-batch fermentation process

Piriformospora indica, a mycorrhizal-like fungus able to establish associations with roots of a wide range of plants, supporting plant nutrition and increasing plant resistance and tolerance to stress, was shown to solubilise phosphate applied in the form of animal bone char (HABO) in fermentation systems. The process of P solubilisation was caused most likely by proton extrusion and medium pH lowering. The fungal mycelium was successfully immobilized/retained in a polyurethane foam carrier. Further employment of the immobilized mycelium in repeated-batch fermentation process resulted in at least 5 cycles of P solubilization. The concentration of soluble P increased during the experiment with 1.0 and 3.0 g HABO l−1 and at the end of the 5th batch cycle reached 40.8 and 120 mg l−1, respectively. The resulting final liquid product, without or with solubilized phosphate, was found to significantly increase plant growth and P plant uptake. It can be used as a biostimulant containing microbial plant growth-promoting substances and soluble P derived from renewable sources (HABO) thus supporting the development of sustainable agro-ecosystems.This work was supported by Project CTM2014-53186-R, Ministerio de Economia y Competitividad-ES/EC FEDER Fund and the sabbatical Grant PRX16/00277 to NV

Isolation of polyvinyl chloride degrading bacterial strains from environmental samples using enrichment culture technique

Plastic causes serious damage to the environment, both during its production and disposal. Biodegradation of plastic waste using microbial strain could offer a solution to the problem. Microorganisms have been a good resource for solution to this problem due to their diverse metabolic capability, adaptability to different environment and possibility of isolation using artificial growth media for utilization in situ. In the present investigation, potent microbial strains degrading plastic constituting polymer polyvinyl chloride (PVC) were isolated using enrichment culture technique. To increase the chances of isolating such strain which could have adapted to metabolize plastic constituting polymers, samples were collected from different environmental sites that were rich in plastic waste. These samples were used as a source of microbial culture for enrichment of potential PVC degraders. After then, some bacterial species were subsequently isolated on solid agar medium containing emulsified PVC polymer. The strain PVC 4 characterized as Micrococcus species was found to be more efficient among the other isolates and was chosen for further studies. The biodegradability of PVC by Micrococcus species with PVC as a sole carbon source was determined by their ability to release chloride from PVC polymer, increase their cell density in test media, carbon dioxide production and growth on the surface of PVC film in plate assay. The Micrococcus species showed 0.36% release of chloride and 8.87% mineralization measured in terms of carbon dioxide evolution respectively over a period of 70 days in PVC containing media. The increase in cell density in liquid growth media constituting PVC polymer as a sole source of carbon and growth of cells on the surface of PVC film further substantiate the potential of isolated strain for PVC utilization.Keywords: Polyvinyl chloride, biodegradation, Micrococcus species, enrichment cultur