Agro-waste: a potential fermentation substrate for Penicillium chrysogenum

Common agro-wastes found in Lagos, Nigeria (cassava shavings, corncob, sawdust, and sugarcane pulp) were compared with glucose and lactose as fermentation substrates for Penicillium chrysogenum PCL501. Cassava shavings significantly (P<0.001) produced the highest amount of mycelia weight (0.43 ± 0.02 mg/ml) than all the other substrates. This was followed by corncob with peak mycelia weight of 0.33 ± 0.02 mg/ml. Peak mycelia weight of 0.27 ± 0.01 mg/ml was equally obtained with glucose and sugarcane pulp whereas lactose gave a slightly lower peak of 0.25 ± 0.01 mg/ml. Sawdust gave the least mycelia weight of 0.13 ± 0.01 mg/ml. Total sugar content of all the culture media steadily decreased as fungal growth progressed indicating that the organism utilized carbohydrates for growth and mycelia formation. Cultures containing cassava shavings and sawdust gave high protein peaks of 0.84 ± 0.05 and 0.65 ± 0.03 mg/ml respectively. Cultures containing corncob, glucose, lactose and sugarcane pulp yielded lower protein peaks of 0.37 ± 0.02, 0.30 ± 0.02, 0.24 ± 0.02 and 0.18 ± 0.01 mg/ml respectively. The results suggest that cassava shavings, corncob and sugarcane pulp could serve as cheap fermentation substrates for the growth of the fungus. Of all the substrates investigated, cassava shavings have the best potential to serve as substrate for fermentation by Penicillium chrysogenum PCL501. © 2009 International Formulae Group. All rights reserved

Kinetics and Thermodynamics of Oil Extracted from Amaranth

This chapter deals with the kinetics of solvent extraction of oil from Amaranth, as well as the thermodynamics of the extraction process. Brief introduction of Amaranth and Amaranth oil yields and compositions were given. The justifications of the choice of extraction method, as well as the solvent used in the kinetics and thermodynamic studies, were discussed. Known kinetic models used to model vegetable oils extraction process, were discussed, with the view of evaluating the feasibility of fitting the obtained experimental data into the models. The extraction kinetic models considered are the parabolic diffusion, power law, hyperbolic, Elovich’s and pseudo second order models. The thermodynamics of oil extraction process were also considered. Hence, the thermodynamic parameters, enthalpy, entropy and Gibb’s free energy change of the process were also discussed

Mechanical properties of cubic boron nitride and diamond at dynamical pressure and temperature

We report the mechanical properties of cubic boron nitride (c-BN) and diamond under the combined impact of dynamical pressure and temperature, calculated using ab initio molecular dynamics. Our study revealed a pronounced sensitivity of the mechanical properties of c-BN to applied pressure. Notably, c-BN undergoes a brittle-to-ductile transition at ~220 GPa, consistent across various dynamical temperatures, while diamond exhibits no such transition. Furthermore, the Vickers hardness profile for c-BN closely mirrors that of diamond across a spectrum of temperature-pressure conditions, highlighting c-BN's significant mechanical robustness. These results underscore the superior resilience and adaptability of c-BN compared to diamond, suggesting its potential as an ideal candidate for applications in extreme environments.Comment: 4 figures, 2 table

Physiological behavior of newly isolated Bacterium CB1 and Stenotrophomonas maltophilia strain CB2 on Chrysene, Pyrene, Naphthalene and Fluoranthene

The biodegradability of some polycyclic aromatic hydrocarbons were studied in liquid culture media using bacterial strains (Bacterium CB1 and Stenotrophomonas maltophilia strain CB2) isolated from a former industrial site contaminated with organic and inorganic contaminants. The enrichment experiment was done with chrysene. The partial 16S rRNA gene analyses of Bacterium CB-1 possessed 100% similarity to an uncultured bacterium clone nbt020a while Stenotrophomonas maltophilia strain CB2 had 99% similarity to Paenibacillus sp. Y412MC10. Bacterium CB1 and Stenotrophomonas maltophilia strain CB2 degraded naphthalene between the range of 27% and 42%, chrysene 47% and 12%, fluoranthene 5% and 16%, pyrene 12% and 17% respectively. The strains utilized the test compounds as sole source of carbon and energy. As anticipated, the controls (abiotic and killed) losses were insignificant. The residual PAH obtained in some cases correlated to an increase in cell number indicating that our strains were responsible for the degradation

Phytochemical and antimycobacterial analysis of aqueous and ethanolic extracts of Annona muricata Linn (Soursop)

Against the backdrop evidenced in the threat Tuberculosis poses to developing economies, especially its prevalence among people in their productive (15-45) years; this preliminary study examined the phytochemical constituents and antimycobacterial effect of four (4) aqueous and ethanolic extracts from the fruit skin (epicarp) and leaf of Annona muricata Linn