Introduction: The emergence of drug resistance has caught the attention of scientist due to the risk of going back to the pre-antimicrobial era.

A study was carried out to isolate and screen actinomycetes for antimicrobials from Menengai Crater in Kenya. The actinomycetes were isolated using starch casein agar, Luria Bertani agar and starch nitrate agar. Primary screening for antagonism was carried out using perpendicular method while secondary screening was done using agar disk technique. Extraction of the antimicrobials was carried out using ethyl acetate. Sensitivity testing of the crude extracts against Staphylococcus aureus, Bacillus subtilis, Escherichia faecalis, Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, Xanthomonas campestris, Erwinia carotovora, Candida albicans, Alternaria alternate and Fusarium oxysporum was carried out using agar well technique. Biochemical tests and carbon source requirements were used in characterization of the selected antimicrobial producers. M1 was the best agar medium for isolation of actinomycetes. The number of actinomycetes from regions A, B, C, and D in the crater varied significantly (F = 27.50 P = 0.000). Out of the 156 actinomycetes isolates, 20 isolates were positive for both primary and secondary screening for antimicrobials. There was no significant difference in the zones of inhibition in primary screening of the actinomycetes for antagonistic properties against the test pathogens (F = 1.6957 P = 0.0838). The zones of inhibition after secondary screening varied significantly (F = 2.4473 P = 0.0089). Likewise, there was a significant difference (F = 6.6046 P = 0.001338) in the zones of inhibition after exposing the pathogens to ethyl extracts of the selected antagonistic actinomycetes. There is need to purify and characterize the antimicrobials obtained from the present study.

Growth of fruits which form an important part of human diet has been jeopardized by the many fungal diseases that are present today. This study was conceived to isolate the most common fungal pathogens in passion fruits. Fungi were isolated using potato dextrose agar in addition to characterization using morphological, cultural, and biochemical means. Extraction of essential oils from rosemary (Rosmarinus officinalis) and eucalyptus (Eucalyptus agglomerata) was done. Before carrying the sensitivity test of essential oils to the fungal isolates, constituents of the essential oils were determined. The most common fungal pathogens isolated from passion fruits were Alternaria spp. (45%), Fusarium spp. (22%), Colletotrichum spp. (17%), and Penicillium spp. (16%). There was a relationship between heating time and yield of essential oils in rosemary (r = 0.99) and eucalyptus (r = 0.99). Conversely, there was no significant difference in the amount of essential oils produced by rosemary and eucalyptus (P = 0.08). Furthermore, there was a significant difference in growth inhibition of the fungal pathogens between essential oils from rosemary and eucalyptus (P = 0.000438). Fungal pathogens isolated from passion fruits can be controlled using essential oils from rosemary and eucalyptus. The oils need to be produced in large scale.

BackgroundContaminated water is a major source of enteric diseases. This study aimed at isolating pathogenic bacteria from portable drinking water in Egerton University. In addition, the study aimed at subjecting the isolates to sensitivity test of root extracts from Solanum incanum besides carrying out minimum inhibitory test of the root extracts. Material and methodsThe bacterial pathogens were isolated from water using membrane filtration. The roots were obtained from Solanum incanum plants in the field and dried at room temperature under shade. The root extracts were obtained using methanol, ethanol and water. Sensitivity test of the isolates to the extracts was carried out using disk diffusion technique. Minimum inhibitory technique was carried out using broth tube dilution technique. ResultsThe bacterial pathogens such as Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and Klebsiella sp. were isolated from the water samples. The crude extracts contained tannins, alkaloids, glycosides, flavonoids, resins, phenols and steroids. There was no significant difference between the zones of inhibition produced by the test bacterial pathogens when subjected to crude extracts obtained using methanol, ethanol and water (F=28.57 P=0.07). However, there was a significant difference between the MIC of methanol, ethanol and water extracts. ConclusionPortable water in and around Egerton University is contaminated with potential bacteria pathogens. However, extracts from Solanum incanum can be used as a remedy to the problem. There is need for determination of the structure of active ingredients in the extracts obtained from Solanum incanum.

Drug resistant pathogenic microorganisms account for the highest proportion of death today. This study was aimed at extracting essential oils (EOS) from mint. Sensitivity tests of selected pathogenic microorganism were also carried out. EOS were extracted using distillation method. Phytochemical screening of the essential oils for the presence of tannins, alkaloids, glycosides, flavonoids, resins, phenols and steroids was carried out using standard procedures. Sensitivity test of Staphylococcus aureus (ATCC 25923), Klebsiella pneumoniae (clinical isolate), Escherichia coli ((ATCC 25922), Erwinia carotovora (ATCC 33244), Xanthomonas campestris (ATCC 33913) and Bacillus subtilis (ATCC 6633) to the EOS was carried out using agar well diffusion technique. The minimum inhibitory concentration of the test pathogens by the essential oils was carried out using two-fold serial dilution. The yield of essential oils varied from 1.0±0.01% in first replicate to 3.0±0.03% in the fourth replicate. All the tested phytochemical compounds were present in the EOS of mint. There was no significant difference between the zones of inhibition of the three replicates (F=0.34 P=0.74). In addition, there was no significant difference between the MIC’s of the three replicates (F=0.33 P=0.72). Mint from Egerton University has EOS that can be extracted using distillation method. The EOS were bioactive against the selected bacterial pathogens which creates a need for their mass production.