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Penicillium simplicissimum was isolated from a local dumpsite of Shivamogga district for use in the biodegradation of polyethylene. Degradation was carried out using autoclaved, UV-treated and surface-sterilized polyethylene. Degradation was monitored by observing weight loss and changes in physical structure by scanning electron microscopy, Fourier transform infrared spectroscopy and nuclear magnetic resonance spectroscopy. P. simplicissimum was able to degrade treated polyethylene (38 %) more efficiently than autoclaved (16 %) and surface-sterilized polyethylene (7.7 %). Enzymes responsible for polyethylene degradation were screened from P. simplicissimum. Enzymes were identified as laccase and manganese peroxidase. These enzymes were produced in large amount, enzyme activity was calculated using spectrophotometric method, and crude extraction of enzymes was carried out. Molecular weight of laccase was determined as 66 kDa and that of manganese peroxidase was 60 kDa. Capacity of crude enzymes to degrade polyethylene was also determined. By observing these results, we can conclude that P. simplicissimum may act as solution for the problem caused by polyethylene in nature.

Trichoderma harzianum was isolated from local dumpsites of Shivamogga District for use in the biodegradation of polyethylene. Soil sample of that dumpsite was used for isolation of T. harzianum. Degradation was carried out using autoclaved, UV-treated, and surface-sterilized polyethylene. Degradation was monitored by observing weight loss and changes in physical structure by scanning electron microscopy, Fourier transform infrared spectroscopy, and nuclear magnetic resonance spectroscopy. T. harzianum was able to degrade treated polyethylene (40%) more efficiently than autoclaved (23%) and surface-sterilized polyethylene (13%). Enzymes responsible for polyethylene degradation were screened from T. harzianum and were identified as laccase and manganese peroxidase. These enzymes were produced in large amount, and their activity was calculated using spectrophotometric method and crude extraction of enzymes was carried out. Molecular weight of laccase was determined as 88 kDa and that of manganese peroxidase was 55 kDa. The capacity of crude enzymes to degrade polyethylene was also determined. By observing these results, we can conclude that this organism may act as solution for the problem caused by polyethylene in nature.

The present study was carried out to isolate rubber degrading bacteria and to check the enzymes responsible for degradation, so that the isolates can be effectively used in rubber degradation. Different bacteria were isolated from soil samples and natural rubber samples collected from a rubber processing unit, and were screened for their ability to degrade natural rubber by plate assay. A biodegradation experiment was carried out in the laboratory to confirm degradation. Enzymes responsible for natural rubber degradation were characterized, crude enzyme was extracted by submerged fermentation process and its activity was determined. After extraction of crude enzyme, it was partially purified by dialysis process, and then, the enzyme activity and specific activity were determined. Then, the ability of these enzymes to degrade natural rubber discs were checked. The ability of natural rubber degrading microorganisms to degrade rubber products such as rubber gloves discs and rubber tire discs, was tested. Among the isolated bacterial species, Bacillus subtilis was predominant and showed growth on the natural rubber discs. The biodegradation experiment showed 48.6 % weight loss. It was screened that laccase and manganese peroxidase enzymes are responsible for natural rubber degradation. When enzyme activity was determined, Bacillus subtilis, showed more manganese peroxidase activity compared to laccase activity. Laccase enzyme activity was 0.0138 IU and manganese peroxidase activity was 0.0155 IU. The molecular weights of laccase enzyme (64 kDa) and of manganese peroxidase enzyme (68 kDa) were determined. Biodegradation of rubber by microorganisms was confirmed by Schiff's staining, SEM, FTIR and NMR studies.The term natural rubber or cahuchu (from Indian, caa = tears, ochu = tree cahuchu = weeping tree) refers to a coagulated or precipitated product obtained from latex of rubber plants (Hevea brasiliensis), which forms non-linked but partially vulcanizable polymer chains having molecular masses of about 10 6 Da with elastic properties. Latex serves as a clogging material during healing of wounds caused by mechanical injury of plants.The natural rubber latex is sticky and viscous in nature and very sensitive to temperature, therefore, it cannot be directly used for the manufacturing of rubber products, unless subjected to vulcanization. Due to the special characters of the rubber it is extensively used worldwide. The global rubber consumption was estimated to be 12.5 million metric tons in 2013 of which 65 % were used for tire production and the other 35 % was used for the production of other rubber products (Tsuchii and Tokiwa 1999).The average composition of the natural rubber latex is 25-30 % polyisoprene, 1-1.8 % proteins, 1-2 % carbohydrates, 0.4-1.1 % neutral lipids, 0.5-0.6 % polar lipids, 0.4-0.6 % inorganic components, 0.4 % aminoacids and other 50-70 % water. Dry weight of the natural rubber latex contains more than 90 % of cis-1, 4-polyisoprene and less than 10 % of nonrubber constituents like proteins, car...

Black rot of sweetpotato, caused by Ceratocystis fimbriata, has recently reemerged as a significant threat to sweetpotato production in North Carolina and other states across the United States. This disease has historically been controlled largely through cultural management strategies and, in some cases, fungicide application. The sudden and destructive reemergence of this disease in 2015 created the need for rapidly evaluating disease control strategies. Genetic diversity of current C. fimbriata isolates infecting sweetpotato in North Carolina was assessed using ITS, TEF, and MAT-2 sequences. All 50 tested isolates were confirmed to be of a single mating type, MAT-2, based on PCR amplification. Alignment of ITS, TEF, and MAT-2 sequences revealed all isolates were identical at each locus. Fourteen common sweetpotato cultivars and advanced breeding lines were screened for black rot resistance using two isolates. None of the cultivars were completely resistant to the disease and most were equally susceptible. ‘Stokes Purple’ and ‘Covington’ were the least susceptible, but significantly (P < 0.05) differed only from ‘Bellevue’, the most susceptible cultivar. Sensitivity of 50 C. fimbriata isolates to difenoconazole, fludioxonil, thiabendazole, dicloran, azoxystrobin, pyraclostrobin, fenamidone, and fluazinam was evaluated in vitro. Difenoconazole, thiabendazole, and fluazinam were most effective in reducing mycelia growth. Postharvest fungicide application on black rot-infected roots provided similar results. Low efficacy of dicloran, as well as a range of EC50 values among isolates, suggests potential resistance to this commonly applied fungicide. Results obtained in this study provide current and useful information so that improved recommendations can be made to reduce losses in sweetpotato to black rot.

Natural rubber (NR), or cis-1,4 poly-isoprene, is one of the most important biopolymers. For almost a 100 years, million tons of NR-derived products have been produced by humankind as it is very elastic in nature. These products are mainly made up of NR, which is obtained from the latex of tree Hevea brasiliensis commonly called rubber tree. After usage of these NR products, the disposal of these products is the worldwide solid waste problem. To reduce this problem, microbial degradation of the product should be developed. Microbial degradation is mainly carried out by various microorganisms such as bacteria and fungi. Rubberdegrading organisms were isolated by soil burial method. In the isolated organism, Penicillium chrysogenum effectively degraded the NR sample, and enzyme responsible for degradation was also studied. The present study has showed that it is possible to use this strain to degrade the NR.

A series of naphthalene ring containing 2,4,5-trisubstituted imidazole derivatives (2a-2l) were synthesized using one-pot multicomponent reaction. The reactions were carried out using naphthaldehyde and substituted benzil in the presence of ammonium acetate in acetic acid media. All newly synthesized imidazole derivatives were characterized by FT-IR, 1 H NMR, 13 C NMR and mass spectral analysis. Newly synthesized imidazole derivatives were screened for their in-vitro antioxidant activity by DPPH free radical scavenging assay method and α-amylase inhibition activity by DNS method. All the compounds showed excellent α-amylase activity at 10, 50 and 100 μg/mL and compounds 2d, 2g, 2k exhibited good antioxidant activity.

Screening was done for the isolation of effective lignin degraders from the forest soil samples, by providing lignin as a carbon source through the enrichment method, which leads to the isolation of 8 effective fungal isolates among 14 isolates. Submerged fermentation was done for the production of ligninolytic enzymes with the effective microorganisms by providing Guiaicol as a carbon source. The assay of laccase, lignin peroxidise activity and specific activity was done after the incubation intervals of 2, 4, 6, 7, 8, 10 and 12 days at 27±2°C under shake culture condition. Partially purified protein content was estimated by using Lowry's method. Pleurotus sp. and Phanerochaetae chrysosporium are more effective at the 2nd and 7th days of incubation for the production of laccase and lignin peroxidases among the effective isolates.