Browsing by Author "Bakari, Gaymary George"

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Biological activity of extracts from commiphora swynnertonii against microbes of veterinary importance in chickens
(Sokoine University of Agriculture, 2013) Bakari, Gaymary George
Studies were carried out to establish ethno-botanical information and biological activities of crude extracts from Commiphora swynnertonii against selected microbes of veterinary importance in chickens. Initially, a questionnaire survey was conducted to gather information on practices and knowledge on ethno-botanical uses of C. swynnertonii in the study area. Then extracts from different morphological parts of the study plant were tested against selected bacteria and fungi in vitro using agar well diffusion assay. Resin and root bark extracts showed significant activities (P < 0.001) against S. pyogenes, E. coli and B. subtilis compared to other extracts. The fungi, C. albicans and A. niger, were moderately inhibited. Antiviral activity of the resin and root bark extract was tested in ovo using embryonated chicken eggs inoculated with Newcastle disease virus (NDV). Both extracts significantly (P < 0.001) and effectively reduced virus titres. An animal trial was carried out using the resin and chickens experimentally infected with NDV. Results revealed significant reduction (P < 0.05) in clinical signs and mortality rates following administration of the resin before and after the infection. Prophylactic administration of the extract was found to be more effective than the therapeutic approach. HI titres decreased significantly (P < 0.001) in resin and root bark treated groups and in all chickens treated with resin irrespective of dose given and on whether the extract was administered before or after infection suggesting that the plant materials were capable of destroying the NDV before stimulating the developing chick‘s immunity. Another animal trial investigated the effect of the resin against experimental coccidiosis in chickens. Results showed that oral administration of the resin significantly (P < 0.001) reduced mortality rate. Safety margin of the resin was also investigated by determining its effects on selected physiological and biochemical parameters in chickens. The results revealed a good margin of safety provided that the dosage ranges between 200 to 800 mg resin/kg body weights. A phytochemical study was also carried to determine major bioactive compounds in the resin and root bark extracts. With these studies, it is concluded that extracts from C. swynnertonii especially resin, has significant antibacterial, antifungal, antiviral and anticoccidial effect against the selected microbes. Further research is required to test and validate the extract against other pathogens of medical and veterinary importance.
Correlation between aspergillus flavus fungal biomass and aflatoxin contamination in harvested maize: insights from Kenya and Tanzania
(Tehran university of medical sciences., 2023) Temba, Benigni Alfred; Bakari, Gaymary George; Mgonja, Frida Richard; Mushi, James Richard
Controlling the occurrence of aflatoxins in foods must be accompanied by managing the fungi responsible for their production. The abundance and diversity of aflatoxin-producing Aspergillus flavus are responsible for the accumulation of these toxins in crops, posing a persistent threat to public health and the economy in tropical developing countries. A study was conducted to investigate the occurrence and level of A. flavus and relate them to aflatoxin levels in maize in Kenya and Tanzania. A total of 786 maize samples were collected during harvesting in selected areas of the two countries for analysis. The fungal abundance in the samples was measured as the amount of fungal DNA relative to maize DNA. This was accomplished by quantifying the fungal DNA using qPCR, targeting the internal transcribed spacer (ITS) gene, while the maize DNA was quantified through the alpha-tubulin gene, the two genes known to be conserved. Aflatoxins were quantified using ultra-high performance liquid chromatography, coupled with ultra-high sensitivity, ultra-fast triple quadrupole tandem-mass spectrophotometer. A. flavus was detected in 88.5% of the 786 tested samples, and the average fungal load for these samples (expressed as the log host/pathogen ratio) was 5.53. Aflatoxin occurrence was positive in 31.9% of the samples, with an average level of 2.3 ± 0.643 ppb. The study established a positive relationship between the occurrence and level of aflatoxin B 1 and the presence and biomass of A. flavus, which was statistically proven. These findings emphasize the need to place substantial attention on preharvest control of A. flavus in cereal fields as an effort to control the accumulation of aflatoxin B1 in foods.
Effect of A. nilotica pods and A. lebbeck stem bark extracts on the reproductive system of male mastomys natalensis: an anti-fertility studies
(African journal of biological sciences, 2022) Mwangengwa, Lusekelo Msomba; Bakari, Gaymary George; Kanuya, Noel Lemree; Max, Robert Arsen
The contraceptive potential of Acacia nilotica pods and Albizzia lebbeck stem bark methanolic extracts were evaluated in male rodent pests. Ninety (90) multimammate rats (M. natalensis) were randomized into a 3 × 3 factorial design for treatment groups (control, A. lebbeck and A. nilotica) (n = 10) and treatment durations (15, 30, or 60 days). Control rats consumed plain feed. Treated rats consumed feed with 2% w/w of either of the plant extract. Following treatment, male rats were mated to untreated females before they were sedated in ether and humanely sacrificed. Assessments were done on fertility success rates (number of impregnated females), weight of testes and reproductive glands, sperm cell parameters, and testes histopathology. Fertility success rate was reduced to 0% in the A. nilotica treated rats at all the treatment durations and in the A. lebbeck treated rats after 60 days of treatment. Also, the extract-treated rats revealed a significant reduction in the testes, seminal vesicles, and epididymides weights compared to the control group. Moreover, sperm cell density and the proportions of live and progressively motile spermatozoa were significantly reduced and there were numerous damaged seminiferous tubules reflected by sloughed off germ cells, thinned germinal epithelium and widened empty lumen in the extract- treated rats. Thus, treatment with A. nilotica or A. lebbeck extract in male M. natalensis reduced their fertility success rates through distortion of testicular structure and disruption of spermatogenesis.
Effect of A. nilotica pods and A. lebbeck stem bark extracts on the reproductive system of male mastomysnatalensis : anti-fertility studies
(African Journal of Biological Sciences, 2022-04-05) Mwangengwa, Lusekelo Msomba; Bakari, Gaymary George; Kanuya, Noel Lemree; Max, Robert Arsen
The contraceptive potential of Acacia nilotica pods and Albizzia lebbeck stem bark methano lic extracts w ere ev aluated in male ro d ent pests. N inety (90) multimammate rats ( M. natalensis ) were randomized into a 3 × 3 factorial design for treatment groups (control, A. lebbeck and A. nilotica ) ( n = 10) and treatment durations (15, 30, or 60 days). Control rats consumed plain feed. Treated rats consumed feed with 2% w/ w of either of the plant extract. Following treatment, male rats were mated to untreated females before they were sedated in ether and humanely sacrificed. Assessments were done on fertility success rates (number of impregnated females), weight of testes and reproductive glands, sperm cell parameters, and testes histopathology. Fertility success rate was reduced to 0% in the A. nilotica treated rats at all the treatment durations and in the A. lebbeck treated rats after 60 days of treatment. Also, the extract-treated rats revealed a significant reduction in the testes, seminal vesicles, and epididymides weights compared to the control group. Moreover, sperm cell density and the proportions of live and progressively motile spermatozoa w ere significantly reduced and there w ere numerous damaged seminiferous tubules reflected by sloughed off germ cells, thinned germinal epithelium and widened empty lumen in the extract- treated rats. Thus, treatment with A . nilotica or A. lebbeck extract in male M . natalensis reduced their fertility success rates through distortion of testicular structure and disruption of spermatogenesis.
Maize milling and modifying atmospheric conditions limit formation of aflatoxin B1 by aspergillus flavus
(Macrothink Institute, 2021) Temba, Benigni Alfred; Bakari, Gaymary George
Occurrence of mycotoxins in foods poses a serious health concern all over the world. Aflatoxin B1 (AFB1) is the most toxic, with widest occurrence in various foods, but mainly in cereals and nuts and its accumulation depends on substrate and environmental factors. This study investigated the how physical status (milling) of maize kernels and atmospheric conditions (aeration, moisture and temperature) affect production of aflatoxin B1 by Aspergillus flavus (ATCC 28862). Intact kernels and flour were incubated for up to 20 days in open and partially sealed petri dishes under controlled temperatures of 25 ºC, 30 ºC and 37 ºC and initial moisture contents of 27%, 22%, 18%, 15% and 12%. It was found that on average, significantly higher (p < 0.05) aflatoxin B1 level was accumulated in intact kernels (145.7 µg/kg) as compared to milled kernels (2.2 µg/kg). Also, none of the samples incubated under partially sealed conditions, compared to up to 100% of the samples incubated in open atmosphere had detectable levels of aflatoxin B1 after 20 days. Fungal growth was not affected by milling or aeration, but sporulation was low at 37 ºC and high at 25 ºC and 30 ºC. The findings of this study provide baseline information on how conditions can be modified to control postharvest accumulation of aflatoxin B1 in cereals
Perceptions, attitudes, and practices of Tanzanian university communities regarding the use and formalization of traditional medicine
(European Journal of Medicinal Plants, 2023) Kimario, Wilfrida Adolfu; Mgonja, Frida Richard; Mushi, James Richard; Bakari, Gaymary George; Temba, Benigni Alfred
Introduction: Traditional medicines (TMs) play a vital role in the public healthcare system of Tanzania and other sub-Saharan countries. The community has been advocating for greater recognition and formalization of this sector. Aims: This study aimed to evaluate the community's knowledge and views on formalization to maximize the beneficial use of TMs in Tanzania.Methodology: A cross-sectional survey was conducted among the university community, involving a total of 458 students and staff from three major public universities in Tanzania. Participants were interviewed regarding their history, knowledge, and inclination towards using TMs. They were also asked about their opinions on community involvement and the necessity of strengthening the formalization of education and usage in this field. Results: The results revealed that 84.7% of the participants had utilized TMs, with 71.6% currently using them and 16.8% using them on a regular basis. Furthermore, 30.5% of the participants agreed that the community is aware of the importance of TMs, while 18.8% believed that the community receives adequate education regarding their significance. Additionally, 33.6% indicated that the government recognizes and promotes the importance of TMs. The study also found strong community support for introducing TM practitioners who can attend to patients and provide TMs. There was also strong support for formalizing education on TMs within the Tanzanian education system. Conclusion: The study's findings underscore the significance of recognizing and leveraging traditional medications to improve public health and preserve the benefits of local knowledge.