Diversity of cellulolytic microbes and the biodegradation of municipal solid waste by a potential strain.

Municipal solid waste contains high amounts of cellulose, which is an ideal organic waste for the growth of most of microorganism as well as composting by potential microbes. In the present study, Congo red test was performed for screening of microorganism, and, after selecting a potential strains, it was further used for biodegradation of organic municipal solid waste. Forty nine out of the 250 different microbes tested (165 belong to fungi and 85 to bacteria) produced cellulase enzyme and among these Trichoderma viride was found to be a potential strain in the secondary screening. During the biodegradation of organic waste, after 60 days, the average weight losses were 20.10% in the plates and 33.35% in the piles. There was an increase in pH until 20 days. pH however, stabilized after 30 days in the piles. Temperature also stabilized as the composting process progressed in the piles. The high temperature continued until 30 days of decomposition, after which the temperature dropped to 40°C and below during the maturation. Good quality compost was obtained in 60 days.

Optimization for the production of cellulase enzyme from municipal solid waste residue by two novel cellulolytic fungi.

The main purpose of this study is to reduce the production cost of cellulase by optimizing the production medium and using an alternative carbon source such as municipal solid waste residue. In the present investigation, we aim to isolate the two novel cellulase producing fungi (Aspergillus niger and Trichoderma sp.) from municipal solid waste. Municipal solid waste residue (4-5% (w/v)) and peptone and yeast extract (1.0% (w/v)) were found to be the best combination of carbon and nitrogen sources for the production of cellulase by A. niger and Trichoderma sp. Optimum temperature and pH of the medium for the cellulase production by A. niger were 40°C and 6-7, whereas those for the production of cellulase by Trichoderma sp. were 45°C and 6.5. Cellulase production from A. niger and Trichoderma sp. can be an advantage as the enzyme production rate is normally higher as compared to other fungi.

Effect of Glomus species on physiology and biochemistry of Catharanthus roseus.

The present study on efficacy of different Glomus species, an arbuscular mycorrhizal (AM) fungus (G. aggregatum, G. fasciculatum, G. mosseae, G. intraradices) on various growth parameters such as biomass, macro and micronutrients, chlorophyll, protein, cytokinin and alkaloid content and phosphatase activity of pink flowered Catharanthus roseus plants showed that all Glomus species except G. intraradices enhanced the chlorophyll, protein, crude alkaloid, phosphorus, sulphur, manganese and copper contents of C. roseus plants along with phosphatase activity significantly over uninoculated plants. However only G. mosseae and G. fasciculatum exhibited superior symbiotic relationship with the plant. G. mosseae was found to be the best for increasing the crude alkaloid content (8.19%) in leaf and also in increasing the quantity of important alkaloids vincristine and vinblastine.

The D1/D2 domain of the large-subunit rDNA of the yeast species Clavispora lusitaniae is unusually polymorphic.

Ten different versions of the D1/D2 divergent domain of the large-subunit ribosomal DNA were identified among interbreeding members of the yeast species Clavispora lusitaniae. One major polymorphism, located in a 90-bp structural motif of the D2 domain, exists in two versions that differ by 32 base substitutions. Three other polymorphisms consist of a two-base substitution, a two-base deletion, and a single-base deletion, respectively. The polymorphisms are independent of one another and of the two mating types, indicating that the strains studied belong to a single, sexually active Mendelian population. Several strains were heterogeneous for one or more of the polymorphisms, and one strain was found to be automictic and capable of producing asci on its own by isogamous conjugation or by bud-parent autogamy. These observations suggest circumspection in the use of sequence divergence as the principal criterion for delimiting yeast species.

Improvement in bioavailability of tricalcium phosphate to Cymbopogon martinii var. motia by rhizobacteria, AMF and Azospirillum inoculation.

The interactive effects of phosphate solubilizing bacteria, N2 fixing bacteria and arbuscular mycorrhizal fungi (AMF) were studied in a low phosphate alkaline soil amended with tricalcium insoluble source of inorganic phosphate on the growth of an aromatic grass palmarosa (Cymbopogon martinii). The microbial inocula consisted of the AM fungus Glomus aggregatum, phosphate solubilizing rhizobacteria Bacillus polymyxa and N2 fixing bacteria Azospirillum brasilense. These rhizobacteria behaved as "mycorrhiza helper" and enhanced root colonization by G. aggregatum in presence of tricalcium phosphate at the rate of 200 mg kg(-1) soil (P1 level). Dual inoculation of G. aggregatum and B. polymyxa yielded 21.5 g plant dry weight (biomass), while it was 21.7 g in B. polymyxa and A. brasilense inoculated plants as compared to 14.9 g of control at the same level. Phosphate content was maximum (0.167%) in the combined treatment of G. aggregatum, B. polymyxa and A. brasilense at P1 level, however acid phosphatase activity was recorded to be 4.75 pmol mg(-1) min(-1) in G. aggregatum, B. polymyxa and A. brasilense treatment at P0 level. This study indicates that all microbes inoculated together help in the uptake of tricalcium phosphate which is otherwise not used by the plants and their addition at 200 mg kg(-1) of soil gave higher productivity to palmarosa plants.

Anti-tobacco socialization in homes of African-American and white parents, and smoking and nonsmoking parents.

PURPOSE: To examine parental perceptions and behaviors with regard to teen smoking, comparing African-American and white parents, and those who did and did not smoke. METHODS: Focus groups consisting of African-American and white parents who smoked provided initial in-depth information. A computer-assisted telephone survey of a biracial sample of 311 parents of children ages 8 to 17 years provided more generalizable information regarding parental beliefs and behaviors. RESULTS: Nearly 50% of households either allowed teen smoking, had no ground rules, or had set restrictive rules but never communicated them to the children. Compared to white parents, African-American parents felt more empowered to affect their children's behaviors and were more likely to actively participate in anti-tobacco socialization within the home (all p values < 0.01). Among the African-American parents, 98% reported 18 years or older to be an appropriate age for teens to make up their own minds about using tobacco, whereas 26% of white parents thought 16 years to be an appropriate age (p < 0.001). Parents who smoked reported more frequent rule-making than those who did not smoke (p = 0.02), but were more likely to believe that childhood tobacco use is inevitable (p = 0.01). CONCLUSIONS: Many parents are not engaged in antitobacco socialization in the home. Differences in the degree of parental participation may contribute to the variance in smoking prevalence between African-American and white children.

Response error in self-reported current smoking frequency by black and white established smokers.

As compared with white smokers, black smokers, although they report using fewer cigarettes per day, are at higher risk for most smoking-related diseases. Among black smokers serum cotinine levels are also higher in proportion to cigarettes per day; this observation has led to suggestions of bias in self-reporting. The purpose of this study was to evaluate and compare the extent of errors in self-reported smoking patterns among black and white established smokers. Ninety-seven white and 66 black smokers participated in structured telephone interviews, filled out two self-administered questionnaires one week apart, and collected all of their cigarette butts for a week. Group differences in the validity of self-reported smoking patterns were assessed by comparison with cigarette butt counts and the measured butt lengths. Both black and white smokers significantly overestimated smoking on our measure of smoking frequency (both P < 0.001); the group difference in bias was not significant (P = 0.13). There was no evidence that underreporting was more common among blacks than among whites (P = 0.67). Test-retest reliability was not significantly different in the two groups (P = 0.09). Both groups performed poorly when asked to categorize their smoking frequency according to the cutpoints of the Fagerström Test for Nicotine Dependence. Black smokers smoked more of each cigarette and smoked longer cigarettes, but they smoked fewer total millimeters of cigarettes per day (all P < 0.001). Contrary to an earlier report, the disproportionately high cotinine levels could not be attributed to reporting error.

Short communication: Protoplast formation from the thermophilic fungus Malbranchea sulfurea, using the thermostable chitinase and laminarinase of Paecilomyces varioti.

Two thermostable enzymes produced by the thermophilic fungus Paecilomyces varioti, a chitinase and laminarinase, were used to isolate protoplasts of a thermophilic fungus, Malbranchea sulfurea. The frequency of protoplast regeneration observed (35%) was considerably higher than that obtained using commercial lytic enzymes.

Effect of a detergent Triton X-100 on growth and alpha-glucosidase production by the thermophilic fungus Malbranchea sulfurea.

A detergent Triton X-100 was found to affect maltose-induced synthesis of extracellular, mycelial and intracellular alpha-glucosidase in the thermophilic fungus Malbranchea sulfurea. The extracellular fraction of the total alpha-glucosidase yield was found to be 90.7% and 40.4% in the presence and absence of the detergent, respectively. Data suggest that supplementation of the detergent in the medium resulted in the partial solubilization of the cell-bound alpha-glucosidase and caused its release in the growth medium.

Improved production of extracellular α-amylase, by the thermophilic fungusMalbranchea sulfurea, following protoplast fusion.

Protoplasts of a catabolite-repression-resistant strain ofMalbranchea sulfurea and a mutant of it over-producing amylase were isolated and fused using electrofusion. The yield of hybrids was 5×10(-5). One stable hybrid, DGCS 1, was insensitive to glucose repression and produced approx. twice the α-amylase activity produced by either of its parents. The amount of DNA in DGCS 1 was also double that of either parent strain.

Hybrid construction by fusion of protoplasts of Endomycopsis fibuligera and Saccharomyces cerevisiae.

Protoplasts of an ethanol-producing strain of Saccharomyces cerevisiae (rho-, Cyc R, Ket R) and amylase-producing yeast Endomycopsis fibuligera (rho+, Cyc S, Ket S) were fused, which resulted in starch fermenting hybrids. The fusion frequency was 2 x 10(-7). The morphological appearance of the hybrids was similar to the petite parent S. cerevisiae strain. The amount of DNA in the hybrid was found to be slightly higher when compared with the individual parental strain.