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Study’s Novelty/Excerpt • This study investigates the antibacterial potential of endophytic fungi associated with Psidium guajava leaves against Escherichia coli and Klebsiella pneumoniae, revealing novel antimicrobial properties. • Through isolation and identification of eight endophytic fungi, four were found to exhibit significant antibacterial activity. • This work highlights the potential of endophytic fungi from P. guajava as a promising source of new antibacterial agents, contributing to the ongoing search for solutions to antimicrobial resistance. Full Abstract Antimicrobial resistance has been recognized as a major issue of public health concern and it remains a global threat of the health care system. Endophytic fungi associated with medicinal plants are reported as promising reservoir of novel antibiotics. The study aim was to determine the antibacterial potential of endophytic fungi associated with Psidium gaujava leaf against Escherichia coli and Klebsiella pneumoniae. Leaves of P. guajava were surface sterilized and inoculated on plates of Potato Dextrose Agar and incubated at room temperature. Endophytic fungal isolates that emerged were identified using their macroscopic (cultural) and microscopic characteristics. The endophytes were screen for antibacterial activity on E. coli and K. pneumoniae isolates. Antibacterial activity of endophytic fungi ethyl acetate extracts with antibacterial activity was also evaluated against isolates of E. coli and K. pneumoniae by agar well diffusion technique. Minimum Inhibitory Concentrations and Minimum Bactericidal Concentrations of the ethyl acetate extracts were also determined. Eight endophytic fungi were isolated from P. guajava leaves and four had antibacterial activity namely: Gonatobotrys sp. P21, Xylaria sp. P11, Fusarium sp. P22 and Trichoderma sp. P25. The extracts exhibited antibacterial activity with zones of inhibition ranging from 11.5 ± 0.5mm to 18.5 ± 1.5mm for E. coli and 12.5 ± 0.5mm to 21.0 ±1.0mm for K. pneumoniae. The MIC was found to be 500mg/mL and 250mg/mL for E. coli and K. pneumoniae respectively. Endophytic fungi isolated from P. gaujava leaf are potential source of novel antibacterial drug since they possess antibacterial activity against isolates of E. coli and K. pneumoniae.

There is an increasing demand for high fructose corn syrup as an alternative to glucose especially for use by people with diabetes due to its low glycemic index. The high cost of this product coupled with its high demand has attracted the attention of many researchers to search for an alternative and sustainable production route. Therefore, the focus of this work was isolating and screening Aspergillus niger and Bacillus coagulans as possible producers of amylase and glucose isomerase respectively, which are needed to produce high fructose corn syrup. Nine (9) samples of loamy soil were taken from three (3) separate locations (BG = Botanical Garden, RD = Refuse Dumpsite, FB = Flower Bed) to isolate the bacterium and fungus. Based on the lacto-phenol cotton blue stain preparation under a microscope, colonies that were thought to be Aspergillus niger colonies were observed and further identified. Cultural, microscopic, and biochemical characteristics were used to confirm the identification of colonies that were thought to be Bacillus coagulans. The probable isolates of Aspergillus niger and Bacillus coagulans were then screened for amylase and glucose isomerase production respectively. Out of the total of nine (9) soil samples analysed, 5 (55.6 %) were positive for Aspergillus niger. A higher isolation rate of Aspergillus niger, 2 (66.7 %) was recorded in soil samples from botanical garden (BG) and flower bed (FB). The lowest isolation rate, 1 (33.3 %) was observed in soil obtained from the refuse dump. Out of all the isolates screened for their potential to produce amylase, the isolate from the botanical garden showed the highest zone of starch hydrolysis (28 mm), and the isolate from the flower bed showed the least zone of hydrolysis of starch (13 mm). On the other hand, out of the nine (9) soil samples analysed, 6 (66.7 %) were positive for Bacillus coagulans and the highest occurrence of Bacillus coagulans, 3 (100 %) was recorded with soil from botanical garden (BG1), while the least occurrence, 1 (33.3 %) was observed in soil from flower bed (FB2). The probable isolates of Bacillus coagulans screened for glucose isomerase production revealed that all the six (6) isolates produced glucose isomerase, with isolate from refuse dump (RD2) producing the highest concentration of glucose isomerase (4.7014 g/L).

The increasing discharge of dyes into the environment and their consequential ecological effects has necessitated the need for the ecofriendly decolourization methods. Laccases became enzymes of research interest due to their broad substrates specificities. The aim of the study was to purify, characterize and determine the decolourization ability of Curvularia lunata SS17 produced laccase. Laccase was produced using maize cob as substrate under optimized culture conditions and purified using Gel Filtration Chromatography. Biuret method was then used to estimate the protein contents of the crude and partially purified laccase. Specific activities, purification fold and yield (%) of the crude and purified laccase enzyme were also estimated. Decolourization potentials of the crude and partially purified enzyme were evaluated using four dyes namely: Congo red, Methylene blue, Bromocresol green and direct yellow. Elution profile of partially purified laccase revealed that fraction 5 had the highest laccase activity (3.654 U/mL). Optimum conditions for enzyme activity were estimated to be 35oC and pH 6. Enzyme activity of the partially purified laccase (3.654 U/mL) was observed to be higher than that of the crude laccase (1.635 U/mL). Also, the partially purified laccase had higher specific activity (1.87 U/mg) compared to that of the crude laccase (0.41 U/mg). Higher percentage dye decolourization potential was observed using the partially purified laccase compared to the crude laccase. Increase in percentage decolourization of the dyes by the partially purified laccase as well as crude laccase was observed as incubation time proceeds.

The problem of tuberculosis (TB) in Nigeria has been made worse by the issues of drug resistant Mycobacterium tuberculosis. Resistance associated with treatment failures has become a common occurrence worldwide. Of particular concern is the increasing prevalence of multi drug resistant M. tuberculosis; organisms resistant to isoniazid and rifampicin, the two drugs that form the backbone of modern short-course therapy. Susceptibility of forty (40) M. tuberculosis isolates to isoniazid (INH), rifampicin (RIF), streptomycin (SM) and ethambutol (EMB) was determined by the proportion method on Lowenstein Jensen egg based slopes containing critical concentrations of INH, RIF, SM and EMB (0.2 μg/ml, 40 μg/ml, 4.0 μg/ml and 2.0 μg/ml respectively). Overall drug resistance was found in 21 (52.5%) isolates. Mono-drug resistance was seen in 9 (22.5%) of the isolates tested and was against streptomycin. Two (5.0%) isolates were found to be MDR. Five (12.5%) were poly-drug resistant. One isolate showed poly-drug resistance to SM and INH, 2 (5%) were poly-drug resistant to SM and EMB, 1 (2.5%) was resistant to INH and EMB. Poly resistance to SM, INH and EMB was found in only 1 isolate. No poly-resistance to RIF and EMB, RIF and SM or RIF/SM/EMB was observed.

Bioethanol production from lignocellulosics as an alternative automobile and engine fuelhas received a considerable attention from researchers worldwide. In the current work, Bioethanol was produced from sulfuric acid and alkaline hydrogen peroxide treated rice stalk employing simultaneous saccharification and fermentation process using co-cultures of isolated and characterized strains of A. niger and S. cerevisiae. The proximate composition of the substrate was determined following standard procedures described by Association of Official Analytical Chemist. The composition of the substrate treated with sulfuric acid was moisture (4.95%), ash (4.75%), fats (4.50%),protein (5.25%), fibre (50.90%),carbohydrates (80.55%), while that of alkaline peroxide-treatment was moisture (3.65%),ash (5.10%), fats (6.60%),protein (7.00%), fibre (38.65%) andcarbohydrates (77.65%). At optimal fermentation conditions of 35ºC temperature, 5.0 pH, 4% substrate concentration, 300rpm agitation rate and 4 days fermentation period and after determining the quantity of the ethanol produced using specific gravity method, a maximum of 5.06g/100ml and 3.91 g/100ml of ethanol was obtained from sulfuric acid and hydrogen peroxide treated rice stalk respectively. The qualitative analysis using FTIR-Spectrophotometry shows the absorbance peaks of the ethanol functional groups from all the ethanol samples produced and the functional groups had their absorption peaks within their normal ranges of 3100-3600cm-1, 2800-3000cm-1 and 1600-1675cm-1 for hydroxyl, alkane and alkene functional groups respectively.

Corrosion in deadlegs occurs as a result of water separation due to the very low flow velocity. This work aims to investigate the effect of geometry and orientation on flow field and oil/water separation in deadlegs in an attempt for the development of a deadleg criterion. The investigation is based on the solution of the mass and momentum conservation equations of an oil/water mixture together with the volume fraction equation for the secondary phase. Results are obtained for two main deadleg orientations and for different lengths of the deadleg in each orientation. The considered fluid mixture contains 90% oil and 10% water (by volume). The deadleg length to diameter ratio (L/D) ranges from 1 to 9. The results show that the size of the stagnant fluid region increases with the increase of L/D. For the case of a vertical deadleg, it is found that the region of the deadleg close to the header is characterized by circulating vortical motions for a length 1 [approximately equal to] 3 D while the remaining part of the deadleg occupied by a stagnant fluid. In the case of a horizontal deadleg, the region of circulating flow extends to 3-5 D. The results also indicated that the water volumetric concentration increases with the increase of L/D and is influenced by the deadleg orientation. The streamline patterns for a number of cases were obtained from flow visualization experiments (using 200 mW Argon laser) with the objective of validating the computational model.

Food fermentation has been a tradition for decades due to its immense benefits. Lactic acid bacteria are known to possess probiotic potential due to various chemical antimicrobial substances they produce. This research was aimed at isolating Lactobacillus spp. from locally fermented locust beans and screening the isolates for their probiotic potential. A total of 20 samples of fermented locust beans (P. biglobosa) were collected and processed. The samples were inoculated onto de-Mann Rogosa Sharpe (MRS) media and incubated anaerobically. The isolates with characteristic colonial morphology of Lactobacillus sp. were characterized using Gram staining and biochemical tests. Lactobacillus spp. isolates were screened in-vitro for probiotic potential using the following parameters, tolerance of low pH, bile tolerance and antimicrobial activity. Four isolates of Lactobacillus species consisting of Lactobacillus fermentum and Lactobacillus plantarum were isolated from different fermented locust beans. All isolates showed tolerance to low pH and bile concentration of 3.04 and 0.3%, respectively. The Lactobacillus species isolates showed varying antibacterial activity against all test bacteria with isolate S06 (L. plantarum) showing the highest degree of antibacterial activity. In conclusion, the Lactobacillus species isolated from fermented locust beans can serve as probiotic candidate. [ABSTRACT FROM AUTHOR]

Context: Carissa edulis Vahl (Apocynaceae) is used in Nigerian folk medicine to manage a plethora of diseases including epilepsy, cancer, and inflammation; its efficacy is widely acclaimed among communities of northern Nigeria. Objective: This study establishes anticonvulsant activities of aqueous fraction of ethanol root bark extract of Carissa edulis (RAF) and sub-fractions (S1 and S2) in animal models. Materials and methods: We evaluated the acute toxicity of the RAF, S1 and S2, and the anticonvulsant activity using pentylenetetrazole (PTZ), picrotoxin, strychnine, N-methyl- d-aspartate (NMDA), isoniazid (INH), and aminophylline-induced seizures in mice. Their effects on maximal electroshock (MES) and kindling-induced seizures were studied in chicks and in rats, respectively, and in the electrophysiological study. The doses used for RAF were 150, 300, and 600 mg/kg while S1 and S2 were 250, 500, and 1000 mg/kg. Both RAF and sub-fractions were administered once during the experiment. Results: The intraperitoneal LD50 of the RAF was estimated to be 2222.61 mg/kg and that of the S1 and S2 were above 5000 mg/kg. RAF protected the mice by 50% while sub-fractions by 16.67% against PTZ-induced seizures. RAF offered 33.33 and 16.67% protection against strychnine and NMDA models, respectively. However, RAF offered 66.67-33.33% protections against aminophylline-induced seizures at doses of 150 and 600 mg/kg, but RAF, S1, and S2 had no effect on MES-induced seizures. Discussion and conclusion: Our results validate the use of the plant traditionally in the management of epilepsy, thus supporting the appraisal of biologically active components of this plant as antiepileptic agents. [ABSTRACT FROM AUTHOR]

Hygiene practices in food processing plants are important determinants of food quality and safety. Poor hygiene practices may result in the contamination of foods and food products with pathogens, which means a serious risk to public health. This study was aimed at isolating and determining the antibacterial susceptibility profile of Listeria spp. and Staphylococcus aureus from smoked fish sold within Ahmadu Bello University Main Campus. A total of twenty-five (25) smoked fish samples were collected. Fifteen (15) samples, five each from Community market, Akenzua market and ICSA Ramat market were processed and inoculated on Mannitol Salt Agar for the isolation of Staphylococcus aureus. The remaining ten (10) samples were processed using stomacher and on Listeria Selective Agar (Oxford formulation) for the isolation of Listeria spp. The isolates were characterized based on their colonial morphology, Gram’s and biochemical reactions. In addition, agglutination test was carried out to further identify Listeria spp. Antibacterial susceptibility patterns of the isolates was determined using disc diffusion method. Staphylococcus aureus was isolated from all the 15 samples analyzed, giving an occurrence of 100%. However, only one Listeria spp. (Listeria ivanovii) was isolated from the 10 samples analyzed, with a 10% occurrence. All the S. aureus isolates were susceptible to most of the antibiotics, but four were resistant to rocephin and eight to ampiclox. The Listeria ivanovii isolate was also resistant to most of the antibiotics and susceptible to only two. The Multiple Antibiotics Resistance Index (MARI) of S. aureus isolates ranges from 0.2 to 0.4 while it was 0.75 for the Listeria ivanovii isolate. The study demonstrated that smoked fish sold in Ahmadu Bello University Main Campus were found to be contaminated and its consumption is potentially regarded as a health hazard, as such measures should be adopted to control it.

Staphylococcus aureus and Pseudomonas aeruginosa have been implicated as important nosocomial pathogens causing severe infections especially in hospitalized patients. The aim of the study was to assess the antibacterial activity of Aloe vera gel against multidrug resistant S. aureus and P. aeruginosa isolated from wound. Clinical isolates of S. aureus and P. aeruginosa from wound infection were collected from Microbiology laboratory of Barau Dikko Teaching Hospital (BDTH), Kaduna and re-confirmed using standard microbiological procedure. Antibiotic susceptibility pattern of the isolates was determined using Kirby Bauer disk diffusion method. Aloe vera gel was obtained fresh matured leaves of Aloe vera plant and was screened for the presence of phytochemical constituents. Antibacterial activity of the Aloe vera gel against Multidrug Resistant (MDR) Staphylococcus aureus and Pseudomonas aeruginosa isolates was determined by agar well diffusion technique. The result revealed that all the two isolates were resistant to more than three classes of antibiotics. The Staphylococcus aureus isolate was resistant to fluoroquinolone (ciprofloxacin), aminoglycoside (gentamicin), cephalosporin (cefaroline), folate pathway antagonist (trimethoprim-sulfamethoxazole), penicillin(cefoxitin) and macrolide (erythromycin) while the Pseudomonas aeruginosa isolate was resistant to β- lactam (ticarcillin-clavulanate), fluoroquinolone (ciprofloxacin and norfloxacin), aminoglycoside (gentamicin) and cephalosporin (ceftazidime)hence regarded as MDR isolates. Phytochemical screening of the gel revealed the presence of saponins, flavonoids, terpenoids and alkaloids. The Aloe vera gel was found to have antibacterial activity against the test isolates with MIC and MBC values of 25µg/mL and 50µg/mL against MDR S. aureus 50µg/mL and 100µg/mL against MDR P. aeruginosa respectively. The study identified that Aloe vera gel possesses antibacterial activity against MDR S. aureus and P. aeruginosa isolated from wound infection.

Milk is a nutritive food that serves as an excellent growth medium for wide variety of microbes. This study was conducted to determine the occurrence of Staphylococcus aureus in powdered milk sold in Samaru market, Zaria, and their antibiotic susceptibility patterns. Fifty (50) powdered milk samples were collected from different shop vendors. The samples were used for isolation of Staphylococcus aureus by cultural method. Staphylococcal count was determined and the colonies observed were identified based on colonial morphology, microscopic and biochemical characterization. The antibiogram of the isolates were also determined using Kirby-Bauer disc diffusion method. The highest Staphylococcal mean count of 1.47x104 CFU/g was observed in powdered milk samples displayed outside the shop in sacks and the lowest count of 1.22x104 CFU/g was observed for samples displayed inside the shop in sacks. Fifteen (15) samples were positive for Staphylococcus aureus giving a percentage occurrence of 30%, with samples displayed outside the shop in sacks having the highest occurrence (42.9%) while the least (16.67%) occurrence was observed in those displayed inside the shop in sacks. The antibiogram revealed a high susceptibility to Ciprofloxacin (100%), Gentamicin (93.33%), Erythromycin and Chloramphenicol (73.33%). While other isolates showed high resistance to Norfloxacin (66.67%) and Ampicillin-cloxacillin (26.67%). Five (5) isolates were resistant to multiple antibiotics with multiple antibiotic resistance index (MARI) ranging from 0.3-0.4. The study revealed high occurrence of Staphylococcus aureus in powdered milk and its resistance to commonly used antibiotics possess a public health risk to consumers of these products

Hepatitis B virus is known to thrive in peripheral mononuclear cells, tissues of pancreas, spleen, kidney, skin, fluids such as saliva, semen, sweat, breast milk, tears, urine as well as vaginal secretion. This study was carried out to determine the seroprevalence of Hepatitis B virus infection and associated risk factors among pregnant women attending antenatal care in General Hospital Azare, Bauchi State. In this study, 100 consenting pregnant women were recruited and their blood samples were screened for HBs Ag using Rapid Test Strip. A structured questionnaire was used to obtain information about the socio-demographic and risk factors of the study population. Data obtained were subjected to Chi-square test using statistical package for social science (SPSS) version 20 to determine the association between risk factors and Hepatitis B virus infection. The result showed that the overall seroprevalence of Hepatitis B virus infection among pregnant women attending General Hospital, Azare, was 6(6.0%). Highest seroprevalence of HBsAg (16.7%) was observed among pregnant women within the age group of 36-40 years so also unemployed pregnant women (6.8%) had the highest seroprevalence of HBs Ag. Previous history of blood transfusion, previous history surgery, use of contraceptives, sharing of sharp objects and sharing of tooth brush were found to be the risk factors associated with pregnant women in Azare. The differences observed in the seroprevalence of HBs Ag with different demographic and risk factors were not significant (P>0.005), with the exception of age (p = 0.03). Pregnant women and the general public should be enlightened on the risk factors associated with hepatitis B virus infection.

Context: Decoctions of Randia nilotica Stapf. (Rubiaceae) have been used in the Nigerian traditional medicine for the management of epilepsy, anxiety, depression and psychosis for many years and their efficacies are widely acclaimed among the rural communities of Northern Nigeria. Objective: The aim of this study is to establish whether the saponins present in R. nilotica are responsible for its acclaimed beneficial effects in Nigerian traditional medicine. Materials and methods: The behavioural properties of the saponin-rich fraction (SFRN) of R. nilotica stem bark were studied on hole-board, diazepam-induced sleep, rota-rod and beam-walking in mice. The anticonvulsant properties of SFRN were also examined on maximal electroshock, pentylenetetrazole- and strychnine-induced seizures in mice. Results: The intraperitoneal LD50 of SFRN in mice and rats were estimated to be 11.1 and 70.7 mg/kg, respectively. SFRN significantly prolonged the duration of diazepam-induced sleep; diminished head dip counts in the hole-board test and protected mice against maximal electroshock seizures. SFRN failed to protect mice against pentylenetetrazole- and strychnine-induced seizures; and had no effect on motor coordination on the rota-rod treadmill at the doses tested. SFRN significantly decreased the number of foot slips in the beam-walking assay in mice with no effect on time to reach the goal box. Discussion and conclusion: This study provides evidence of the psychopharmacological effects of SFRN, thus supporting further development of the psychoactive components as remedies for epilepsy. [ABSTRACT FROM AUTHOR]

Primary glioblastomas (GBMs) commonly overexpress the oncogene epidermal growth factor receptor (EGFR), which leads to increased Ras activity. FTA, a novel Ras inhibitor, produced both time- and dose-dependent caspase-mediated apoptosis in GBM cell lines. EGFR-mediated increase in 3H-thymidine uptake was inhibited by FTA. FACS analysis was performed to determine the percent of apoptotic cells. The sub-Go population of GBM cells was increased from 4.5 to 13.8% (control) to over 45–53.6% in FTA-treated cells within 24 h. Furthermore, FTA also increased the activities of both caspase-3 and -9, and PARP cleavage. Treatment of GBMs with FTA before or after EGF addition to the cultures blocked phosphorylation of Akt and mitogen-activated protein kinases (MAPK). FTA also significantly reduced the amount of EGF-induced Ras-GTP as reflected by a decrease in the level of Ras bound to Raf-RBD-GST. This study demonstrates that inhibition of Ras methylation may provide a therapeutic target for the treatment of GBMs overexpressing EGFR.Cell Death and Differentiation (2006) 13, 642–651. doi:10.1038/sj.cdd.4401783; published online 21 October 2005 [ABSTRACT FROM AUTHOR]

Toxoplasmosis is a zoonotic infection of both humans and animals and has a worldwide distribution. A total of 300 blood samples were collected from school children in Kaduna state. The sera were screened for Toxoplasma gondii IgM and IgG antibodies by Enzyme Linked Immunosorbent Assay (ELISA). The seropositive samples were screened for T. gondii specific B1 gene. Out of the 300 blood samples screened for Toxoplasma IgM antibody, 108 (36.0%) were positive while 50 (16.67%) were seropositive for the Toxoplasma IgG antibody. So also 24 (8.0%) samples were seropositive for ToxoplasmaIgG+IgM antibodies. B1 gene specific forT. gondiiwas detected by PCRin the ELISA positive samples.This confirms the presence of the parasite among the school children in Kaduna state.

Urinary schistosomiasis is endemic in Nigeria, and continues to pose public health challenges, especially among the inhabitants of rural areas. Urinary schistosomiasis occurs in all the states of Nigeria with the highest infection rate among school age children between 6 to 17 years. This study aimed at determining the prevalence of Schistosoma heamatobium infection among primary school pupils in Zangon shanu Zaria, and its relationship with some physicochemical indices of urine, studied through urinalysis. A total of one hundred and fifty (150) urine samples (75 samples from each of the two schools) were collected and examined using sedimentation technique. The parameters examined include symptoms of the disease as haematuria (presence of blood in urine), proteinuria (presence of protein in the urine) and dysuria (painful urination). The associations of risk and demographic factors with the disease were also examined, using structured questionnaire. An overall prevalence of 5.33% with 7.5% among male and 1.8% among female was obtained. The age group 13-16 years has the highest prevalence of 9.8%among the rest. The research also revealed the statistical association of shistosomiasis with haematuria, proteinuria and dysuria(p