Biocidal effects of stem bark extract of Chrysophyllum albidium G. Don on vancomycin-resistant Staphylococcus aureus.

Background: Staphylococcus aureus causes variety of infections in humans and animals worldwide and predominates in surgical wound infections. This study assessed the antimicrobial potential of the stem bark extract of Chrysophyllum albidum against an array of vancomycin resistant Staphylococcus aureus (VRSA) isolated from clinical samples.

Methods: The methanolic crude extract of the plant was preliminary screened for the presence of phytochemicals; after then, the extract was partitioned into n-hexane, chloroform, ethyl acetate and butanol fractions.

Probable mechanisms of biocidal action of Cocos nucifera Husk extract and fractions on bacteria isolates.

Background: The incidence of resistance to the existing antibiotics by microorganisms demand increased effort in the development of new antibiotics for the treatment of microbial infections and diseases. Infections due to multidrug resistant pathogens are difficult to manage due to relatively limited choices of antimicrobial agents. This study investigated antimicrobial activities of the husk extract of Cocos nucifera on some bacteria that are associated with human diseases.

Evaluation of Antibacterial and Antifungal Properties of Alchornea laxiflora (Benth.) Pax. & Hoffman.

Alchornea laxiflora leaf extract was tested against a range of microorganisms using standard microbiological methods for antimicrobial activities. The extract inhibited the growth of all the bacterial and 15 fungal isolates tested. The zones of inhibition exhibited against the test bacteria ranged between 12 mm and 24 mm and between 11 mm and 24 mm for the extract and the antibiotic streptomycin, respectively.

Stem bark extract and fraction of Persea americana (Mill.) exhibits bactericidal activities against strains of bacillus cereus associated with food poisoning.

The study investigates the in vitro antibacterial potentials of stem bark extracts of Persea americana on strains of Bacillus cereus implicated in food poisoning. The crude stem bark extracts and butanolic fraction at a concentration of 25 mg/mL and 10 mg/mL, respectively, exhibited antibacterial activities against test isolates. The zones of inhibition exhibited by the crude extract and the fraction ranged between 10 mm and 26 mm, while the minimum inhibitory concentration values ranged between 0.

Preliminary phytochemical screening and antibacterial properties of crude stem bark extracts and fractions of Parkia biglobosa (Jacq.).

A methanolic crude extract of Parkia biglobosa was prepared and later partitioned in succession with different solvents of increasing polarity ranging from n-hexane, chloroform and ethyl acetate to butanol. Phytochemical screening of the extract revealed the presence of alkaloids, tannins, saponins, flavonoids, steroids, glycoside and sugars. The inhibition zones exhibited by the extract against the tested bacteria ranged between 14 ± 0.

In-vitro antibacterial properties of crude aqueous and n-hexane extracts of the husk of Cocos nucifera.

The increasing numbers of cases of antibiotic resistance among pathogenic bacteria such as Vibrio species poses a major problem to the food and aquaculture industries, as most antibiotics are no longer effective in controlling pathogenic bacteria affecting these industries. Therefore, this study was carried out to assess the antibacterial potentials of crude aqueous and n-hexane extracts of the husk of Cocos nucifera against some selected Vibrio species and other bacterial pathogens including those normally implicated in food and wound infections. The crude extracts were screened against forty-five strains of Vibrio pathogens and twenty-five other bacteria isolates made up of ten Gram positive and fifteen Gram negative bacteria.

Antibiotic producing potentials of three freshwater actinomycetes isolated from the Eastern Cape Province of South Africa.

Crude extracts of three actinomycetes species belonging to Saccharopolyspora (TR 046 and TR 039) and Actinosynnema (TR 024) genera were screened for antibacterial activities against a panel of several bacterial strains. The extracts showed antibacterial activities against both gram-negative and gram-positive test bacteria with inhibition zones ranging from 8 to 28 mm (TR 046); 8 to15 mm (TR 039); and 10 to 13 mm (TR 024). The minimum inhibitory concentrations ranged from 0.

Microwave assisted synthesis and antimicrobial activity of 2-quinoxalinone-3-hydrazone derivatives.

A simple and efficient method has been developed for the synthesis of various 2-quinoxalinone-3-hydrazone derivatives using microwave irradiation technique. The series of 2-quinoxalinone-3-hydrazone derivatives synthesized, were structurally confirmed by analytical and spectral data and evaluated for their antimicrobial activities. The results showed that this skeletal framework exhibited marked potency as antimicrobial agents.

Studies on the biocidal and cell membrane disruption potentials of stem bark extracts of Afzelia africana (Smith).

We had recently reported antibacterial activity in the crude extract of the stem bark of Afzelia africana (Akinpelu et al., 2008). In this study, we assessed the biocidal and cell membrane disruption potentials of fractions obtained from the crude extract of the plant.