Purification and identification of antibacterial compounds from Euclea crispa subsp. crispa (Ebenaceae) leaves

The isolation, purification and identification of antibacterial compounds from Euclea crispa subsp. crispa reported here, is a continuation of earlier work. Most of the antimicrobial activity was located in an ethyl acetate fraction obtained by means of liquid–liquid extraction. Subsequent purification of this fraction, by means of multiple preparative thin layer chromatography using different solvent systems, revealed the presence of essential oils, bitter principles and saponins, all terpenoid derivatives, as well as alkaloids and phenolic compounds. A terpenoid that tested positive for bitter principles and for saponins, and possessed a steroidlike structure, was isolated and purified from the ethyl acetate fraction. This compound was active against the Gram-negative Moraxella catarrhalis. Also isolated from the ethyl acetate fraction, and showing antimicrobial activity as individual compounds, were five flavonoids identified as catechin, epicatechin, gallocatechin, hyperoside and quercitrin. Of these epicatechin and hyperoside were most active in inhibiting the growth of M. catarrhalis (−), Streptococcus pneumoniae (+) and Haemophilus influenza (−). The isolated flavonoids seemed, in general, to have less activity than the entire ethyl acetate fraction, suggesting that these compounds function in synergy

Influence of egg shell as heterogeneous catalyst in the production of biodiesel via transesterification of Jatropha oil

The increase in energy demand together with the negative global environmental impacts of using fossil fuel for energy generations brings a question on dependability on it for sustainable economic growth. The way out is the use of renewable sources of energy such as biodiesel which has significant advantages over its counterpart (fossil fuel). Biodiesel can be produced through various methods such as transesterification, micro emulsion and pyrolysis. The influence of egg shell as heterogeneous catalysts in the production of biodiesel via transesterification of Jatropha oil was investigated. The physical and chemical properties of the catalyst were studied using scanning electron microscopy (SEM) and Xray fluoroscopy (XRF) characterizations. The crude Jatropha oil was transesterified and 0.1 wt%, 0.2 wt%, 0.3wt%, 0.5wt% and 0.5wt% of egg shell were used as heterogeneous catalyst during transesterification process. Fourier Transform Infrared (FTIR) was used to determine the functional group of the samples. SEM and FTIR characterizations indicate the presence of dispersed particles on the catalyst and ester (biodiesel) on the samples respectively. The maximum percentage of biodiesel yield is 94.3% at the application of 0.2wt% egg shell as catalyst using 1:6 oil to methanol ratio in 1hr at 60-65℃. This indicated that the egg shell has high potential to be used as catalyst in the production of biodiesel via transesterification of Jatropha oil

Introduction of household biogas digesters in rural farming households of the Maluti-a-Phofung municipality, South Africa

The study aimed to introduce biogas as an alternative source of energy for rural cattle farmers in the Maluti-a-Phofung municipality in the Free State Province, South Africa. To augment the rural farming community’s adoption of the biodigester technology the following initiatives were undertaken: (i) a situational analysis (or diagnostic survey); (ii) training on biogas production in an integrated crop-livestock-bioenergy system; (iii) installation of the biodigesters; and (iv) monitoring and evaluation of the biogas production. Results on the diagnostic survey showed that the main source of energy for cooking was wood in all the farms and availability of water was not a constraint. Prefabricated biodigesters of 6m3 -12m3 were installed in all the households and, after continual feeding of the units with cattle dung, the production of biogas increased gradually. Monitoring of biogas production showed that, in two-thirds of the households, 80% of their cooking needs were met in summer, while in winter biogas production was minimal due to extremely cold weather. Challenges faced included non-adherence to a feeding regime – resulting in a blockage of the biodigester – and lack of feeding. Generally, farmers in the study area showed a high appreciation of the biodigester technology

Lack of modulatory effect of asparagus, tomato, and grape juice on cyclophosphamide-induced genotoxicity in mice

Studies on agents that modulate carcinogen-induced genotoxic effects in experimental animals are used to assess the antimutagenic or anticarcinogenic properties of putative chemopreventivecompounds. We investigated the potency of asparagus-, tomato- and red grape-juice to modify the proportion of polychromatic erythrocyte (PCE) and frequency of micronucleated polychromatic erythrocytes (MNPCE) induced by cyclophosphamide (CP) in male NIH mice. Groups of five mice were given the fruit juices (25, 50 or 100%) respectively, ad libitum, for 44 days then intraperitoneally (ip) injected with 40 mg/kg CP and killed 24 h later for cytological preparations and analysis. The control group animals were injected with CP (positive) or purified water (negative). Each group mean of the proportion of PCE and frequency of MNPCE was compared with the negative and positive control usingthe Mann-Whitney test. No statistically significant difference was found between the proportion of PCE in any experimental group and the negative control (