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- ItemGENETIC VARIABILITY AND ANTIRETROVIRAL DRUG RESISTANCE AMONG DRUG-NAÏVE HIV TYPE-1 INFECTED PATIENTS IN KADUNA STATE, NIGERIA(2023-06)An important feature of HIV pandemic is the global genetic diversity of the virus. Emerging HIV genetic variants results to adverse consequences related to pathogenesis, transmission, diagnosis, clinical management and vaccine production. Expansion of antiretroviral (ARV) types and regimens over the last few decades to reduce viral transmission, morbidity and mortality related to HIV disease has resulted in emergence of transmitted drug resistance which poses serious threat to the public health. The prevalence of transmitted drug resistance in resource-limited countries is about 5%, it is however projected to increase with ART expansion. This study was aimed at determining the viral genetic variability and antiretroviral drug resistance among drug-naïve HIV type-1 infected patients in Kaduna State, Nigeria. The study was a cross-sectional hospital based one that adopted the probability proportional to size (PPS) sampling method. Basic demographic data of each volunteer was captured using structured questionnaire and transcribed to electronic questionnaire using Epi Info® version 7.2.2.2.6 software. A total of fifty HIV infected drug-naïve adult participants were enrolled in this study from three voluntary counseling and testing (VCT) centers in Kaduna State, Nigeria. These participants were tested positive to HIV from April to October, 2018. The prevalence of HIV-1 was determined using Multispot™ HIV-1/HIV-2 rapid test kit. The CD4 cell counts and viral load were determined using FACS Flow cytometry and COBAS® TaqMan® HIV-1 Test respectively. Protease and reverse transcriptase regions of pol gene were sequenced using Sanger DNA sequencing reaction. Web-based resistance database was used to analyse the sequence reads. GraphPad Prism version 6.0 was used to analyse the collated data. Quantitative variables were presented as mean (±SD) and median (IQR), while Spearman correlation was used to compare the CD4 cell count and viral load. Level of significance of 95% was adopted to accept or reject null hypothesis at p ≤ 0.05. Socio-demographic data of the study participants were determined. All (100%) the HIV infected participants studied were found to be infected with HIV type 1. The study population was found to have relatively high median viral load 158,391 Copies/m with median CD4 cell count of 176 ceel/μL. However, few participants, despite being ART-naïve, had undetectable plasma viral load. Female had higher CD4 cells count values and lower plasma HIV-1 viral load value than male. The CD4 cells had strong reciprocal relationship with the plasma HIV-1 viral load. There was strong negative significant value of correlation coefficient between HIV-1 plasma viral load and CD4 cells count in the study population. The prevalence of transmitted drug resistance was found to be 19.5 % which is very high in the study area. The HIV-1 isolates were characterized into CRF02_AG, subtype G, CRF06_cpx and subtype C with frequency of 25(61%), 13(32%), 2(5%) and 1(2%) respectively. A protease inhibitor surveillance drug resistance mutation (SDRM) as M46MI, few other NRTI and NNRTI SDRM and other polymorphic mutations were detected among the drug-naïve HIV infected patients. The K103NSG mutation was highest with a frequency of 12.8 % (5/39). Genetic relatedness of the sequences from the isolates and reference sequences were presented in maximum likelihood phylogenetic tree. This study indicates that the baseline plasma viral load and CD4 cell count could affect prognosis, disease progression and transmission. The drug-naïve participants reported with undetectable plasma RNA could be ‘‘elite’’ controllers. This implies that, the patients may respond to the currently available highly active antiretroviral therapy (HAART) first line treatment.
- ItemGENETIC VARIABILITY AND ANTIRETROVIRAL DRUG RESISTANCE AMONG DRUG-NAÏVE HIV TYPE-1 INFECTED PATIENTS IN KADUNA STATE, NIGERIA(2023-06)An important feature of HIV pandemic is the global genetic diversity of the virus. Emerging HIV genetic variants results to adverse consequences related to pathogenesis, transmission, diagnosis, clinical management and vaccine production. Expansion of antiretroviral (ARV) types and regimens over the last few decades to reduce viral transmission, morbidity and mortality related to HIV disease has resulted in emergence of transmitted drug resistance which poses serious threat to the public health. The prevalence of transmitted drug resistance in resource-limited countries is about 5%, it is however projected to increase with ART expansion. This study was aimed at determining the viral genetic variability and antiretroviral drug resistance among drug-naïve HIV type-1 infected patients in Kaduna State, Nigeria. The study was a cross-sectional hospital based one that adopted the probability proportional to size (PPS) sampling method. Basic demographic data of each volunteer was captured using structured questionnaire and transcribed to electronic questionnaire using Epi Info® version 7.2.2.2.6 software. A total of fifty HIV infected drug-naïve adult participants were enrolled in this study from three voluntary counseling and testing (VCT) centers in Kaduna State, Nigeria. These participants were tested positive to HIV from April to October, 2018. The prevalence of HIV-1 was determined using Multispot™ HIV-1/HIV-2 rapid test kit. The CD4 cell counts and viral load were determined using FACS Flow cytometry and COBAS® TaqMan® HIV-1 Test respectively. Protease and reverse transcriptase regions of pol gene were sequenced using Sanger DNA sequencing reaction. Web-based resistance database was used to analyse the sequence reads. GraphPad Prism version 6.0 was used to analyse the collated data. Quantitative variables were presented as mean (±SD) and median (IQR), while Spearman correlation was used to compare the CD4 cell count and viral load. Level of significance of 95% was adopted to accept or reject null hypothesis at p ≤ 0.05. Socio-demographic data of the study participants were determined. All (100%) the HIV infected participants studied were found to be infected with HIV type 1. The study population was found to have relatively high median viral load 158,391 Copies/m with median CD4 cell count of 176 ceel/μL. However, few participants, despite being ART-naïve, had undetectable plasma viral load. Female had higher CD4 cells count values and lower plasma HIV-1 viral load value than male. The CD4 cells had strong reciprocal relationship with the plasma HIV-1 viral load. There was strong negative significant value of correlation coefficient between HIV-1 plasma viral load and CD4 cells count in the study population. The prevalence of transmitted drug resistance was found to be 19.5 % which is very high in the study area. The HIV-1 isolates were characterized into CRF02_AG, subtype G, CRF06_cpx and subtype C with frequency of 25(61%), 13(32%), 2(5%) and 1(2%) respectively. A protease inhibitor surveillance drug resistance mutation (SDRM) as M46MI, few other NRTI and NNRTI SDRM and other polymorphic mutations were detected among the drug-naïve HIV infected patients. The K103NSG mutation was highest with a frequency of 12.8 % (5/39). Genetic relatedness of the sequences from the isolates and reference sequences were presented in maximum likelihood phylogenetic tree. This study indicates that the baseline plasma viral load and CD4 cell count could affect prognosis, disease progression and transmission. The drug-naïve participants reported with undetectable plasma RNA could be ‘‘elite’’ controllers. This implies that, the patients may respond to the currently available highly active antiretroviral therapy (HAART) first line treatment.
- ItemEFFECT OF STREPTOCOCCUS THERMOPHILUS ON PERFORMANCE, SURVIVAL AND GUT BACTERIAL FLORA OF CLARIAS GALMAENSISANDCLARIAS GARIEPINUS HYBRID(2023-06)The use of probiotics in aquaculture has shown great potentials in substituting for antibiotics in fish culture as growth promoters and in preventing fish mortality. However, the problem of antimicrobial resistance poses a great threat to human health and has therefore led to the ban of the use of medically important antibiotics in animals as growth promoters. This restriction in the use of antibiotics has led to the discovery and adoption of probiotics. This study was carried out to investigate the probiotic effect of Streptococcus thermophilus isolated from the rumen of cattle on the growth performance, nutrient utilization, survival rate and gut bacterial flora of23DPH hybrid using standard methods. Varying probiotic concentrations 1.5×107CFU/ml, 1.5×108 CFU/mland 1.5×109 CFU/ml of S. thermophilus was administered to three treatment groups ofthe hybrid for 56 days, while the control group was not administered with S. thermophilus. The results showed no significant effect (p≥0.05) of the bacterium on the growth performance and nutrient utilization of the fry but showed significant association (p≤0.05) with its survival rate. The fry survival rate was higher withS.thermophilus concentration of 1.5×109 CFU/ml. The carcass proximate compositions of the fry revealed diminishing protein and lipid contents with increasing S. thermophilus concentrations, while carbohydrate content increased with increasing probiotic concentrations.S. thermophilus did not influence the gut viable bacterial count, however it influenced the gut bacterial isolates and composition. It was observed from this study that S. thermophilus does not have significant effect on the growth performance and nutrient utilization on Clarias hybrid fry but significantly increased its survival rate at 1.5×109 CFU/ml. This study therefore recommend that Streptococcus thermophilus at 1.5×109 CFU/ml can increase surival rate of fry.
- ItemBIOASSAY- GUIDED ISOLATION AND CHARACTERIZATION OF A TRYPANOCIDEFROMMISTLETOE (VISCUM ALBUM) EXTRACTS(2023-06)Viscum album is a parasitic plant of immense medicinal significance and was evaluated for antitypanosomal potential. Fresh leaves and stemof V. albumwas obtainedfrom the following host plants;Azadirachta indica, Psidium guajava, Acacia albida, Khaya senegalensis and Moringa oleifera. The extracts were prepared by cold maceration using methanol. In vitro anti-trypanosomal screening of the extracts against T. b. brucei was carried out in 96 well microtiter plates at final concentrations of 0.8, 0.4, 0.2, 0.1 and 0.05 mg/mL. A bio-assay guided isolation of the active compound was carried out by repeated silica gel column chromatography, monitored by TLC. Structuralelucidation wasperformed by 1D and 2D NMR. The LD50 of HDN-one was evaluated in mice using OECD method. Body weights of mice were taken daily for two weeks and clinical signs of toxicity were observed. In vivo effect of the compound isolated was evaluated on Trypanosoma bruceibrucei infected mice. The results showed that leaves and stem of V. album harvested from A. albida and A. indica hadin vitro activity against Trypanosoma brucei brucei. Leaves and stem of V. album from A. albida had 75% and 57.50% inhibition respectively while leaves and stem of V. album from A. indica had 61.21% and 59% respectively. Viscum album leaves from A. albida had the highest anti-trypanosomal activity (IC50 = 0.30 mg/mL). Qualitative phytochemicalscreening of the methanol extract ofV. album leaves from A. albida showed the presence of alkaloids, tannins, saponins, anthraquinone, phenols, steroids, terpenes, courmarins, flavonoids, and glycosides. Quantitative phytochemistry of the phenolics, flavonoids, alkaloids, and saponins revealed 0.82, 0.04, 1.91, and 2.02% composition respectively.Sequenial extraction of the methanol extract of V. album leaves from A. albidawith n-hexane, ethyl acetate, and n-butanol showed thatn-butanolfraction had the highest yield of 45.26% and was themost active fraction against Trypanosoma brucei brucei (IC50 = 0.84 mg/mL). Bioassay- guided fractionation of n–butanol fraction and subsequentpurification of the resulting bioactive compound led to the isolation of [2-(4- hydroxyphenyl) ethyl]-2,6-dioxabicyclo [3.3.1] nonan-3-one (HDN-one)with in vitro antitrypanosomal activity against T. b. brucei (IC50 = 0.26 mg/ mL). The compound did not show toxicity in mice at a dose level of 2000 mg/kg bw. There was a significant decrease in parasitemia of the group treated with the compound compared to infected untreated group. The compound had no inhibitory effect on the activity of trypanosome alternative oxidase (TAO) and trypanosome glycerol kinase (TGK). In conclusion, the results of this study revealed that HDN-one isolated from V. album leavesdid not show signs of toxicity in mice at a dose level of 2000 mg/kg body weight and had in vivo anti-trypanosomal activity against T. b. brucei.
- ItemBIOETHANOL PRODUCTION FROM CORN COB USING CO-CULTURE OF ZYMOMONAS MOBILIS AND BACILLUS LICHENIFORMIS(2023-06)There have been growing interest about biosynthesis of fuels from renewable biomass resources due to depleting fossil resources and associated environmental issues in the past few decades. Bioethanol is considered to be a good choice for an alternative liquid fuel because it can be produced from a variety of agricultural renewable materials. Proximate analysis of corn cob was carried out and the results revealed that the substrate had the following nutritional composition: moisture (13.50%), ash (14.90%), crude protein (3.50%), lipid (1.00%) and carbohydrate (67.10%). The corn cob used in this research work had lipid and protein contents that can serve as sources of energy for microbial growth and replication. The substrate was rich in carbohydrates that have great potential for bio-ethanol production. In the present research work, Zymomonas mobilis an ethanologenic bacterium was isolated from palm sap and characterized molecularly by amplification of the alcohol dehydrogenase I gene and the 16SrRNA gene. A total of 10 Xylose fermenting Bacillus species were also isolated from the soil and characterized biochemically and through sequencing of the 16SrRNA genes. The sequences with their accession numbers have been deposited in the gene bank. The following Bacillus species were characterized: Bacillus amyloliquifaciens (20%), Bacillus licheniformis (20%), Bacillus thuringiensis (30%), Bacillus cereus (10%) and Bacillus subtilis (10%). Zymomonas mobilis isolates ZM2 and ZM3 were screened for alcohol tolerance and glucose fermentation to select the best to be used for bioethanol production. Growth of the two isolates were measured as optical densities at 540nm; Zymomonas mobilis isolate 3 (ZM3) had optical densities that ranged from 0.66-1.40 while ZM2 had optical densities that ranged from 0.34-1.36. ZM2 and ZM3 were also screened for glucose fermentation; ZM3 had ethanol yields that ranged from 30–80g/l while ZM2 had ethanol yields that ranged from 24-60g/l. ZM3 had higher optical densities in the presence of varying alcohol concentrations compared to ZM2 although it was not significantly different (P≥0.05). Similarly, ZM3 had higher ethanol yields compared to ZM2 which were significantly different (P≤0.05).The Bacillus isolates were screened for ethanol production from fermentation of xylose and cellulase production to select the best isolate for bioethanol production. The isolates had ethanol yields from the fermentation of xylose that ranged from 18.50-35.5g/l. Bacillus licheniformis (SCFB22) had the highest ethanol yield of 35.5g/l while Bacillus thuringiensis (SBX8) had the lowest ethanol yield of 18.50g/l. The cellulase activities of all the isolates ranged from 1.35-2.98FPU/ml. Bacillus licheniformis (SCFB22) also had the highest cellulase activity of 2.98FPU/ml while Bacillus thuringiensis (SBX3) had the lowest cellulase activity of 1.38FPU/ml. Acetic acid adaptation of Zymomonas mobilis isolate ZM3 was carried out by treating the isolate with varying amounts of acetic acid that ranged from 0.2-1.6 % to enhance the isolates‟ ability to withstand high concentrations of inhibitors like acetic acid during fermentation. Zymomonas mobilis isolate ZMA with a slightly enhanced tolerance to relatively high acetic acid concentrations was obtained. Submerged fermentation of corn cob hydrolysate was carried out using acetate adapted ZMA isolate, the parent Zymomonas mobilis isolate (ZM3) and xylose fermenting Bacillus licheniformis in set ups that contained co-culture of the two bacteria and those containing the single strains. High bioethanol yields of 38.6g/l and 35.3g/l were obtained from the coculture submerged fermentation of corn cob hydrolysate using acetate adapted Zymomonas mobilis (ZMA) and xylose fermenting Bacillus licheniformis (SCFB22) as well as co-culture submerged fermentation using the parent Zymomonas mobilis isolate (ZM3) and Bacillus licheniformis (SCFB22). Submerged fermentation using single isolates yielded relatively lower bioethanol contents. Isolates ZMA, Zymomonas mobilis ATCC 29191, ZM3, SCFB22 and Bacillus licheniformis ATCC 14580 had bioethanol yields of 32.1, 31.8, 31.9, 12.8 and 14.5g/l respectively. The acetate adapted isolate (ZMA) also had a higher ethanol yield of 32.1g/l than the parent isolate (ZM3) which had ethanol yield of 31.8g/ml. The results of the one way ANOVA that was carried out showed that the ethanol yields obtained from the coculture fermentation using different isolates were significantly different (P≤ 0.05). Co-culture fermentation using Zymomonas mobilis isolate ZMA, ZM3 and Bacillus licheniformis isolate SCFB22 have great potential for industrial bioethanol production using agricultural waste (corn cob). The physicochemical parameters of the bioethanol produced were all similar to that of the commercial 98% ethanol used in this study but with some variation in some of the parameters. All the bioethanol produced were colourless, the relative densities of the bioethanol produced ranged from 0.77-0.84g/cm3 while that of the commercial ethanol was 0.76 g/cm3.The variation in the relative densities of the bioethanol produced could be due to the different types of bacteria used in the set ups or the different bioethanol yields. The boiling points of the bioethanol produced were similar to that of the commercial ethanol. The boiling points of the bioethanol produced ranged from 78.6-78.9ºC while that of the commercial ethanol was 78.6ºC. The flash points of the bioethanol produced ranged from 14-16ºC while that of the commercial ethanol was 13ºC. The variation observed in the flash point of the bioethanol produced could be due to the fact that the bioethanol produced contained more water that the commercial ethanol. All the bioethanol produced as well as the commercial ethanol burned with a blue flame. The result of the physicochemical parameters of the bioethanol produced suggests that the bioethanol produced are of good quality and could serve as substitutes to conventional ethanol.