Human vitamin deficiencies still occur in many countries although most vitamins are present in a variety of foods, mainly because of malnutrition not only as a result of insufficient food intake but also because of unbalanced diets; this work screens some Lactic acid bacteria isolated from selected Nigerian fermented foods for vitamin (thiamine, riboflavin and niacin) production. Five lactic acid bacteria were isolated from selected Nigerian fermented foods (yoghurt, ogi, ogiri, ugba). The isolated lactic acid bacteria were identified based on cultural and biochemical characteristics. All the isolates were screened for thiamine, riboflavin and niacin production using microbiological assay. Thiamine, riboflavin and niacin produced were quantified.

This study has been embarked upon due to increased resistance of bacteria to many already synthesized drugs and the high price of the orthodox medicines in the market, the antimicrobial effect of Psidium guajava leaf extracts against selected drug-resistant bacteria will help to reduce the overdependence on orthodox or synthetic drugs which greater population of the society cannot afford due to economic/financial restriction. Ethanolic and aqueous extracts of Psidium guajava were assayed for antibacterial activity using the agar dilution method in the determination of the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). The bioactive components of the extracts were determined using standard techniques and the inhibitory activities of the extracts were compared to gentamicin, ciprofloxacin, erythromycin, azithromycin, ofloxacin, and nitrofurantoin. The MIC of the extract on the test organisms ranges from 10 mg/ml -40 mg/ml. The sensitivity test showed that the organisms were susceptible to Psidium guajava leave extract except Pseudomonas aeruginosa. The phytochemical analysis of the extracts revealed the presence of bioactive compounds such as Tannin, Saponin, Balsam, Flavonoids, Alkaloids, Cardiac glycosides, Carbohydrate, Resins, Terpenes, and Sterols. It has been shown that the leaves of Psidium guajava have antibacterial effects and hence can be used to treat the ailments caused by those organisms at a particular dosage and concentration. However, more research work on its toxicity level, synergistic or antagonistic interaction with other plants or drugs is needed to consolidate its usage.

In the quest to produce an acceptable local beverage that could serve as an alternative variety to kunun-zaki for many millions of Nigerians who take the cereal-based beverage as their most preferred and affordable drink a study was undertaken to assess the microbial and sensory quality attributes of laboratory-produced Date fruit-based kunun-zaki. Different blends of dry date fruits (Phoenix dactylifera) and sorghum (Sorghum bicolor) formulated as follows; F1 (100:0), F2 (70:30), F3 (50:50), and F4 (30:70%) of date fruits/sorghum were soaked overnight in water, drained and were wet-milled with ginger and cloves using an equal volume of sterile water, F5 (0:100) was market (Control) sample. The microbial succession study included the identification of organisms at various critical stages of the production of the beverage. The results of the study showed the mean pH, and TTA (%) values for the respective formulated Kunun-dabino product were F1 (4.87 and 0.3870), F2 (4.66 and 0.4508), F3 (4.29 and 0.4600), F4 (4.04 and 0.4690), F5/Control (4.32 and 0.4589) respectively. The mean Total bacterial, coliform and fungal loads of the four experimental products were 2.58 x 104, NIL, and 3.56 x 103 CFU/ml respectively which fall within W.H.O’s recommended standards for ready-to-eat foods. Species of Bacillus, Enterobacter, Shigella, Lactobacillus, Aspergillus, Penicillium Mucur, and Candida were present at the initial production stage while Bacillus and Lactobacillus species persisted right through to the final stage of production. The results of the sensory evaluation showed that while F1 was the least liked, F3 was significantly preferred over the other samples (P < 0.05). The study has shown that ‘Kunun dabino’ produced under the laboratory conditions in this study provides a new brand of beverage that is both microbiologically safe and organoleptically more acceptable to taste panelists.

For production and preservation of traditional fermented foods, the genera, lactic acid bacteria (LAB) have been used. This study was carried out to determine the characteristics and the antimicrobial activities of lactic acid bacteria isolated from selected Nigerian traditional fermented foods. Changes in pH and titratable acidity (TA) of the samples were investigated for a period of four days (96 h). Eleven tentative LAB from fermented maize and cassava (Ogi and Fufu, respectively) were isolated and characterized. The spoilage organisms from fish were aseptically identified and the antimicrobial activity was determined by agar well diffusion method against three isolated food spoilage organisms (Pseudomonas aeruginosa, Enterobacter aerogene and Bacillus cereus). The isolates were selected and further identified as Lactobacillus amylolyticus strain L6, Lactobacillus plantarum strain ci-4w and Lactobacillus sakei strain MLS1 by the aide of genotypic characteristics (16S rRNA gene sequences). These strains were screened for their EPS producing activity, resistance to low pH and bile salts as well as bacteriocin activity. These strains can be used as starter culture or protective cultures to improve the hygiene, quality and increased safety of the food products by inhibiting the food borne pathogens and spoilage microorganisms.

Pseudomonas aeruginosa is a major pathogen in humans and other animals, frequently harboring mechanisms of resistance to commonly used antimicrobials. Here, we describe the isolation of P. aeruginosa bacteriophage Zikora. The full 65,837-bp genome was annotated and demonstrates similarity to Pbunavirus phages, making Zikora a new member of this genus of the Myoviridae family.