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Background: Bacteria produce biofilm in a variety of systems; water, implant devices in humans and living tissues. They can be persistent and express virulent factors, increased resistance to antimicrobials and human immunity. Plant-based extracts have shown promising outcomes in inhibiting quorum sensing system and modulation of biofilm formation with lesser side effects. Thus, foliar extracts of Noni plant was the subject of such trial as an antibiofilm/antibacterial agent. Objective: Investigate borehole water sources from three communities in Port Harcourt Local Government Area (PHALGA) for biofilm producers (BPs), antibiogram as well as antibiofilm effect of Noni (Morinda citrifolia) foliar extracts. Method: Microbiological protocols were adopted to isolate and identify bacteria whereas Congo red agar was used to detect biofilm producers (BPs). Antibiogram of BPs were done (with various antibiotics) as well as antibiofilm/antibacterial effect of Noni foliar extracts. Results: Bioassays detected the biofilm producers (BPs) as Staphylococcus aureus, Klebsiella pneumoniae, Bacillus and Serratia species. The bioburden were 55.0±2.5CFU/mL and 51.0±0.2CFU/mL for total heterotrophic bacteria and coliform counts from Ọbaziolu and Rumuelechi communities respectively. Rumuelechi borehole water had the highest percentage relative abundance of S. aureus (80%) and Bacillus (66.7%) whereas Ọbaziolu had Serratia (66.7%) and negative/zero for S. aureus and Ọrora had the least of all the isolated BPs. Antibiogram data revealed that all the BPs were 100% resistant to Cloxacillin and Cotrimoxazole but showed high rate of varying susceptibility to other antimicrobials; S. aureus depicted (100%) susceptibility to Gentamicin and Streptomycin; Bacillus to Tetracycline; Serratia to Augmentin and K. pneumoniae to Gentamicin. All the BPs showed multidrug resistance (MDR) with Serratia and K. pneumoniae being resistant to 6 and Bacillus and S. aureus 5-antibiotics respectively. Furthermore, susceptibility test on these BPs indicated that inhibitory activity of Noni foliar extracts were concentration-dependent. At a concentration of 3000mg/mL methanolic extract (MtE) showed the largest inhibition zone of 20.00mm against B. subtilis and aqueous extract (AqE) 15.00mm on Serratia species and such phenomenon is indicative of broad spectrum activity. Chloramphenicol (control) had the overall largest inhibition zones on the BPs except on B. subtilis. The susceptibility of these crude phytocompounds to BPs promises to be a novel and an alternative natural agent to synthetic antibiofilm products. Conclusion: Biofilm producers were detected in borehole water supply in three communities in Port Harcourt Local Government Area. The predominant BPs were Staphylococcus aureus, Bacillus and Serratia species. The BPs showed multi-antibiotic resistance with the Gram negative bacteria being resistant to more drug-types. Crude phytocompounds of Noni foliar extracts demonstrated broad spectrum activity with promising prospects as likely therapeutic option against biofilm-based infections. Additionally, the degree of multidrug resistance (MDR) depicted by these BPs to conventional antimicrobials is worrisome and demands regular monitoring, environmental sanitation and good hygienic measures to mitigate public health hazards.

Mimosa pudica is a famous ornamental plant commonly known as sleeping grass, sensitive plant, humble plant, shy plant and touch-me not, among other names. The study was aimed at determining the antibacterial activity of Mimosa pudica extract in combination with alum. The plant was obtained, identified, prepared and extracted using both aqueous and methanolic medium. The extracts were reconstituted to final concentration of 250g/ml, 125g/ml, 62.5g/ml (w/v). The bacterial isolates identified were; Pseudomonas aeruginosa NC002516, Staphylococcus aureus FR821779 and Escherichia coli CP031892.1 obtained from wound source at the University of Port Harcourt Teaching Hospital and maintained in stock culture and were further confirmed using biochemical and molecular methods. In-vitro bioactivity of various concentrations of the extracts and in combination with alum were evaluated by measuring diameter of inhibition zones. From the bioassay, the combinations of the aqueous extract and alum demonstrated the highest inhibitory potential; (26.00±0.00mm) at 250g/ml for Staphylococcus aureus FR821779 and the least antibacterial effect was recorded in the consortium extract for Staphylococcus aureus FR821779; (13.00±0.00mm) at same concentration compared with other bacteria (E. coli and P. aeruginosa). The result obtained showed that all the treatments and combination treatments recorded MIC at 0.50g/ml for all the bacteria studied. The composition in percentage of the various phytochemicals were as follows: Flavanoid, 7.96±1.17%, Alkaloid, 9.85±0.21%, Saponin, 7.34±0.35% and Total-phenol, 1.63±0.00%. Alkaloids (9.85±0.21%) had the highest concentrations in the extracts while Total-phenol (1.63±0.00%) was the least in concentration. This study has been able to ascertain the sensitivity profiles of Mimosa pudica leaf extracts and its combination treatment with potassium aluminium sulphate (Alum) on some microbes specifically S. aureus, E. coli, P. aeruginosa.

The study included the isolation, cultural characteristics, molecular identification of bacterial isolated from land snail Achatina achatina and the enhanced antibacterial potential of Xylopia aetiopica extracts in consortium with alum on some bacteria isolated from Achatina achatina (land snail). Isolates associated with the intestine of the snails were isolated using standard microbiological methods and subjected to standard microbiological procedures such as, culturing isolation, identification; the cultural characteristics of all isolated bacterial strains were elucidated on International Streptomyces Project media (ISP2-ISP-7). 16S rRNA marker gene was used for molecular identification using 27F and 1492R universal primers and sensitivity testing using alum and plant extracts (Agar well Diffusion method). Tube dilution method was used to determine the Minimum Inhibitory Concentration (MIC) using double-fold serial dilutions at concentrations 62.5mg/ml to 400 mg/ml. The bacterial isolates identified were; Escherichia coliMW46885, Bacillus cereus AP007209, S. aureus CP051191 and Salmonella typhimurium AE006468. The result of phytochemical component present in X. aethiopica were; Tannin Alkaloid, Flavonoid, and Saponin with values, 2.22±0.08, 5.55±0.78, 6.55±0.21, and 10.55±0.07mg/kg respectively. Results of the inhibitory activity of the extracts and alum were dose-dependent. Methanolic extract of X. aethiopica were more active on E. coli24.50±0.71 at 250mg/ml, Aqueous extract of X. aethiopica were more active on E. coli and Salmonella typhi (21.0±0.00mm), at 250mg/ml and Staphylococcus aureus (20.0±0.00mm) at 125mg/ml and 62.5mg/ml concentrations respectively. Alum were more active on Staphylococcus aureus (25.0±0.00mm) at 250mg/ml concentrations. The result of the combination methanol extract of X. aethiopica and alum showed it more effect on Bacillus cereus (22.0±0.00) at 250mg/ml concentrations. The combination effect of aqueous extract of X. aethiopica and alum revealed the inhibitory effect were more on Bacillus cereus (21.0±0.00) at 250mg/ml concentrations while it was more active on Staphylococcus aureus (15.5±0.71mm) at 62.5mg/ml conc. The result of the combination treatments of methanolic, aqueous extracts of X. aethiopica, and alum showed that the inhibitory effect was more on E, coli and Staphylococcus aureus (18.0±0.00) at 250mg/ml conc., E. coli and Salmonella typhi (15.0±0.00) at 125mg/ml conc. and Salmonella typhi (14.0±0.00mm) at 62.5mg/ml conc. and ciprofloxacin which serves as control has higher inhibition potentials. Xylopia aetiopica has been reported to possess anticancer, antidiabetic, antimalarial, antioxidant, enzyme inhibitory and antibacterial properties. Tube dilution method was used to determine the Minimum Inhibitory Concentration (MIC) using double-fold serial dilutions at concentrations 62.5mg/ml to 400 mg/ml. statistically, there was a significant difference (p≤0.05) in the antibacterial activity of the alum, methanol, and aqueous extracts of X. aethiopica. The minimum inhibitory concentrations at which the extracts were effective against the bacterial isolates was at the 400mg/ml to 300mg/ml concentrations. The MICs values of the extracts and their combinations revealed significantly the inhibitory activities. The study has revealed some level of antibacterial activity and antibacterial activity of the extracts on these bacterial isolates is promising as the extracts could be used as a cheap antibacterial for the treatment of infections caused by these bacteria.

The study examined the role of street trading in reducing poverty in Ikwerre Local Government Area of Rivers State. The objectives were to find out whether street trading increases recurrent income of traders, and to find out if traders derive satisfaction in street trading. The methodology applied was the descriptive design which is tilted towards survey research. We also used purposive sampling technique, since the researcher is conversant with the environment of Igwuruta in Ikwerre Local Government. The findings include that street trading has increased the recurrent income of street traders and has helped in reducing poverty among the traders. Research recommends that street traders should be included in government loan scheme, and traders should be supported by giving them entrepreneurship education.

This study attempts to evaluate culture-dependent microbial and proximate composition of African salad (Abacha) sold at Nkpolu Oroworukwo (mile 3) market, Port Harcourt, Rivers State, Nigeria. Samples were bought from stationary vendors at market within the months of March, 2019 to March, 2021. Garnished African salad (GAS) and ungarnished African salad (UAS) samples were determined by standard microbiological techniques whereas proximate composition (PC) was analysed by the methods of Association of Official of Analytical Chemists (AOAC) Total aerobic plate counts (TAPCs), total coliform counts (TCCs) and fungal counts (FCs) of GAS were higher 4.5x104CFU/g, 5.3x104CFU/g and 1.1x104CFU/g respectively as against 3.4x104CFU/g, 3.8x104 CFU/g and 0.8x104CFU/g for UAG. Microfloral diversity were more in GAS with species such as Escherichia coli, Bacillus subtilis, Klebsiella sp., Micrococcus sp.. Bacillus sp., Enterobacter sp., and Aspergillus sp., Penicillium sp., Rhizopus sp., Fusarium sp., Mucor sp., Saccharomyces and Candida species than in UAS. Nutrient composition, energy (116.00Kcal/100g) and pH (6.4) values were higher in GAS. In contrast, only the moisture (62.52±0.53%) and carbohydrate (23.21±0.21%) contents were slightly higher in UAS than those in GAS. The study revealed that African salad’ bioburden was slightly above the microbiological standard limits of International Commission on Microbiological Specification for Foods (ICMSF) and (Public Health Laboratory Service (PHLS) for RTE foods for mesophilic aerobic bacteria (MAB)/TAPC but exceeded that for total coliforms. However, the microbes detected are likely aetiologic agents of several food borne diseases (FBDs) in human and animal pathologies. Therefore, adequate surveillance, monitoring and compliance with hygienic practices and environmental sanitary measures during processing, fortification and distribution should be enforced by regulatory agencies and stakeholders for wholesome and palatable RTE foods.

Light influences important physiological and morphological responses in fungi, hence they can sense near UV, blue, green, red and far-red lights using up to eleven (11) photoreceptors and signaling cascades to control a larger proportion of the genomes and adapt to environmental factors. Though light is an environmental signal regulating myriad of biological processes, fungi do not utilize it as a source of energy for synthesis of food but for information and other developmental processes. Two genes WC-1 and WC-2 have been identified to function as photoreceptor for blue light proteins or orthologs and transcription factor for other light induced phenomenon. Additionally, conserved WCC photoreceptor orthologs (FaWC1 and FaWC2) may also perform divergent roles in some fungal species such as light signals to regulate UV resistance, secondary metabolism and sexual reproduction as well as for virulent expression. Response to white light irradiation has also elicited different morphological and physiological changes in various species of fungi such as asexual reproduction and induction or inhibition of several developmental processes. Mushrooms also requires light for developmental processes such as the asexual stage for completion of its life cycle whereas it is unnecessary at the vegetative stage. This review provides some recent crucial impact of light irradiation on the developmental processes of fungi such as sporogenesis, germination/conidiation, reproductive development, pathogenesis, mycotoxin and mushroom development even though they are generally known to be achlorophyllous and non-photosynthetic. Thus, identifying conditions of light regime that will favour fungal development with reduced mycotoxin production will be beneficial to animals and human health. Additionally, developing new techniques to control fungal species may lead to the development of faster and more effective food-processing methods.

Aim: The present study investigates the effect of phosphate-solubilizing bacteria (phosphobacteria (PB) and activity of soil bacteriostasis on the development of Azotobacter in Thymus vulgaris rhizosphere. Place and Duration of Study: The study was conducted at Kenule Beeson Polytechnic botanical garden and at the Science Laboratory Department of the institution for a period of 7months (from March 2018- September 2018). Methods: The impact of phytohormones produced by phosphate-solubilizing bacteria in vitro and in the rhizosphere of T. vulgaris was used to assay for Azotobacter colonization. Bacteriostasis activity of the soil was determined by comparing the number of Azotobacter microcolonies on discs incubated over soil with respect to those on the controls. Results: Decisive stimulation of Azotobacter population and establishment was observed in Thymus vulgaris rhizosphere when inoculated with phosphobacteria than when inoculated alone as reflected in 5% (0.05) least significant difference. Azotobacter was susceptible to the bacteriostatic factors in potted soils inoculated with it and without (Azotobacter). The increase in susceptibility of this rhizospheric bacteria was time dependent and reached a maximum and thereafter remained almost constant. However, this was overcome by the addition of NPK fertilizer to the plant at some critical stage of the assay. Conclusion: The Presence of nitrogen fixing bacteria (NFB) in vegetation could play significant role in the sustainability and improvement of plant growth and yield. Soil bacteriostasis can also be an important factor that limits the survival and development of NFB.

Tomato (Solanum lycopersicum) is one of the most economically attractive and widely consumed vegetables globally. Their high water content, perishability, transport and poor storage system predisposes them to spoilage by a broad spectrum of mycoflora resulting in huge postharvest losses. This study investigates antimycotic potential of alum on postharvest deterioration of tomato. Composite samples of deteriorating tomatoes were subjected to standard mycological analysis from which total fungal colony counts obtained ranged from 1.64x106-5.70x109 CFU/g, and the following species were identified; Aspergillus niger, A. flavus, Fusarium sp, Penicillium sp, Rhizopus stolonifer, Geotrichum candidium and Saccharomyces cerevisiae. In vitro antimycotic activity of alum (1% (w/v) concentration) was determined on some of the isolates by agar well method (AWM) and diameter of inhibition zone (DIZ) measured using a metre rule. G. candidum had the highest DIZ (9.0mm (29.0%) followed by A. niger (8.0 mm (25.8%) and 7.0mm (⁓ 22.6%) for Fusarium and Penicillium species respectively. R. stolonifer showed no inhibition or zero. pH values increased from 4.35-4.52 whereas TTA values decreased from 0.13-0.07 within 2days of analysis. However, these results indicate that treatment of postharvest deteriorating tomatoes with alum prior to consumption would enhance food safety as some of these fungi are known to be spoilage, toxigenic or opportunistic pathogens. So, their presence raises concern on storability as well as public health risks associated with consumption of these fruits. Therefore, production of tomato requires an integrated and multidisciplinary research approach not only to reduce economic loss but also create consumers’ awareness on potential public health hazards of consuming relatively cheaper and pathogen contaminated deteriorating tomatoes.

Aims: This work was undertaken to investigate the quality changes in mangrove oysters (Crassostrea gasar ) exposed to various preservative treatments (PTs) including sodium benzoate (NaB), sodium chloride (NaCl), potassium aluminum sulphate (PAS) and green lime juice filtrate (LJF) during ambient temperature storage (30±2oC) to enhance the shelf-life. Study Design: Oyster samples were subjected to various preservative treatments to enhance the shelf-life and the bacteriological, chemical and sensory qualities determined and the data obtained were analyzed.

‘Kwoka’ (a popular Nigerian non-fermented maize meal) was produced using steaming for either 30 or 60 min or a combination of potassium sorbate (KS) treatment with steaming for 60 min. Microbiological characteristics and chemical quality were investigated during production and storage, together with organoleptic and objective (firmness only) assessment of quality during ambient storage (30 ± 2°C). The slurry (ie before steaming) and 30 min steamed K woka showed more diverse genera of moulds and bacteria than K woka steamed for 60 min (with or without KS). The organisms isolated from the raw materials and product belonged to the genera Bacillus, Staphylococcus, Lactobacillus, Enterobacter, Klebsiella, Aspergillus and Fusarium. During storage Bacillus cereus, Lactobacillus delbrueckii, L leichmannii and Klebsiella pneumoniae predominated. Coliforms and fungi were not detected on day 0 in KS-treated and 60 min steamed K woka. Marked reductions in aerobic plate counts (APC) and in the population of the different bacterial groups were observed in all samples following steaming, These increased sharply within 1 day of storage, the highest (6.50 log cfu g−1) APC occurring on day 3 in 30 min steamed K woka. Of the bacterial groups, the Lactobacillus population increased most markedly and this probably reflects the significant increase in acidity observed especially on day 6. Adverse quality changes in appearance, aroma and firmness were more apparent in the control (ie without KS treatment) and the samples were unacceptable after 1 day but the shelf-life of K woka produced using KS treatment and 60 min steaming was extended by 2 days.