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Item Natural recovery of old crop fields in a South African grassland biome(Wiley, 2023-09-18) Coetzer, Willem G.; Coetzer, KayleighChanging land-use practices have led to an increased rate of cropland abandonment in South Africa. Globally, climate change has increased the need for additional studies on the impact of land abandonment on soil health in arid and semi-arid environments. We, therefore, aimed to measure the changes in soil health with time following abandonment. The study site is located in the Winterberg Mountains of the Eastern Cape Province, South Africa. Standard soil characteristics were assessed for three recovering old crop fields. Samples from the surrounding natural habitat were also included for comparison. Significant positive changes in soil water-holding capacity and carbon and nitrogen characteristics were observed with increased age since abandonment, pointing to soil quality recovery. It will, however, still take a significant amount of time for total recovery to be achieved. Continuous monitoring of old crop fields in agricultural and formally protected areas is needed to fully understand the long-term effects of cropping on soil quality in this region.Item A phylogeographic assessment of South African greater cane rats (Thryonomys swinderianus): Preliminary insights(Pensoft Publishers, 2023-03-28) Coetzer, Willem G.The greater cane rat (Thryonomys swinderianus) is an African rodent with a wide Sub-Saharan distribution range. This species is viewed as an important protein source in many African countries. These rodents are also regularly viewed as a pest species who frequently raid croplands in agricultural settings. No phylogenetic work has to date been published on T. swinderianus from southern Africa. This paper therefore reports the first phylogenetic assessment on the species across the South African distribution range. Thirty samples were sourced from local museum collections, with one direct submission by a member of the public who found a rodent carcass identified as T. swinderianus west of its known distribution range in the Eastern Cape Province of South Africa. Two mitochondrial loci previously used in West African studies of this species were used in the current study to asses T. swinderianus population genetic diversity and phylogenetic structure across the South African distribution. A comparison to sequence data from West Africa was also performed. A divergence time estimation was conducted to further investigate the evolutionary history of the South African sub-population. Similar genetic diversity estimates were observed for the South African sub-population when compared to the West African datasets. Specimens from the eastern parts of South Africa showed higher genetic diversity estimates, possibly indicative of an initial colonisation site from eastern Africa. Two distinct phylogenetic clades were identified by Bayesian inference, forming distinct West African and South African groups. The divergence estimates showed similar ages for the T. swinderianus most recent common ancestor (MRCA) as previously reported. The MRCA estimates for the South African group identified a possible middle to late Pleistocene migratory event from eastern African into southern Africa. Further fine scale sampling across the African distribution range is however needed to provide more accurate assessments for future conservation management planning for the different sub-populations, as needed.Item Hypoglycemic, anti-inflammatory, and anti-aging potential of Canthium coromandelicum (Burm.f.) Alston leaf extracts: In vitro and in silico ADMET studies(Elsevier, 2023-08-22) Amalraj, Singamoorthy; Gurav, Shailendra S.; Kalaskar, Mohan G.; Maroyi. Alfred; Ayyanar, Muniappan; Oremu, O.A.The present study focused on the hypoglycemic, anti-inflammatory and anti-aging effects of Canthium coromandelicum (Burm.f.) Alston leaf extract by in vitro and in silico analyses. In vitro antidiabetic activities were studied by a-amylase and a-glucosidase enzyme inhibition assays. The anti-inflammatory activity was analysed by bovine serum albumin denaturation assay and anti-aging activity by the inhibition of tyrosinase enzyme. The molecular docking study was undertaken to examine the binding mode and interactions of reported compounds of the hydroalcoholic extract of C. coromandelicum leaf with 7TAA, 3WY1, 2Y9X, and 4COX proteins. The plant exhibited promising antidiabetic effects with an inhibition of 86.09% against a-amylase and 83.53% against a-glucosidase enzymes. The extract had a notable anti-inflammatory activity with an inhibition range of 50.23 to 73.17%. The anti-aging activity showed 50.31 to 76.78% of inhibition in anti-tyrosinase assay with a potential effect in hyperpigmentation. In molecular docking analysis, the compounds like linoleic acid, phytol, methyl linoleate, palmitic acid and ethyl octa-decanoate had potent inhibitory activities against 7TAA, 3WY1, 2Y9X and 4COX proteins (6.90 to -4.42 kcal/mol) especially linoleic acid was found to be highly effective (-6.11 kcal/mol) antidiabetic effect with notable binding scores. The obtained results suggest that phytoconstituents identified from the plant have the potential in controlling diabetes by inhibiting a-amylase and a-glucosidase enzymes with promising anti-inflammatory and anti-aging properties. However, further research is required to ascertain its potential effect in experimental animals and isolation of bioactive compounds.Item Hepatoprotective activities of polyherbal formulations: A systematic review(AOSIS Publishing, 2023-10-24) Aladejana, Elizabeth B.; Aladejana, Adebowale E.Background: Liver diseases pose a substantial global public health challenge, encompassing conditions such as liver failure, hepatitis, cirrhosis and associated complications Safeguarding the liver becomes important as these conditions impact human health. Hepatoprotective agents play a pivotal role in mitigating liver damage caused by chemicals, drugs and toxins. Polyherbal formulations, combining botanical components from traditional medicine, offer a promising approach to addressing liver disorders. Their popularity arises from a multi-targeted strategy in treating complex diseases, marking a shift in focus toward these formulations. Aim: The study aimed to conduct a thorough review of the existing literature on the hepatoprotective activity of polyherbal formulations and provide a comprehensive overview of their mechanisms of action. This review provides the overview of the use of polyherbal formulations in the management of liver disease. Method: A systematic search of electronic databases, including : Scopus, Academia, Elsevier, Science Direct, Wiley, BioMed Central, PubMed, and Google Scholar, was conducted using a combination of keywords such as ‘polyherbal formulations’, ‘hepatoprotective’ and ‘liver diseases’. Studies published between January 2010 and April 2023 were included in the review. Results: A total of 61 articles were reviewed, and the studies showed that polyherbal formulations possess significant hepatoprotective activity against various hepatotoxic agents. The mechanisms of action of these formulations include antioxidant, antiinflammatory, antifibrotic and antiapoptotic effects. Additionally, some polyherbal formulations were found to stimulate liver regeneration, enhance bile secretion and promote detoxification processes. Conclusion: Polyherbal formulations have shown promising hepatoprotective activity, and their multitargeted approach to treating complex diseases makes them a potential alternative to conventional medicines. However, identifying the active compounds responsible for the hepatoprotective effects of these formulations and their pharmacokinetics and pharmacodynamics could provide insights into the development of new and effective drugs for liver disorders.Item Prevalence of Class 1 Integron and In Vitro Effect of Antibiotic Combinations of Multidrug-Resistant Enterococcus Species Recovered from the Aquatic Environment in the Eastern Cape Province, South Africa(MDPI, 2023-02-03) Adeniji, Oluwaseun Ola; Nontongana, Nolonwabo; Okoh, Anthony Ifeanyi; Sharma, K.Enterococci are regarded as a better indication of faecal pollution in freshwater and marine waters. Their levels in seawater are positively connected with swimming-related gastrointestinal disorders. This study used an Enterococcus-specific polymerase chain reaction (PCR) to characterize the isolates. Classes 1 and 2 integrons were examined for environmental Enterococcus isolates using a standard biological procedure. All strains were assessed against a panel of 12 antibiotics from various classes using disc diffusion methods. The microdilution method was used to work out the minimum inhibitory concentration (MIC) according to the CLSI guiding principles. The combination therapy of the resistant drugs was evaluated using a checkerboard assay and a time-dependent test for assessing their bactericidal or bacteriostatic activity. The gene diversity of the tested organisms was analyzed with the aid of Enterobacterial Repetitive Intergenic Consensus (ERIC) PCR. In total, 57 Enterococcus spp. environmental samples were recovered, in which Enterococcus faecalis (33.33%) and Enterococcus faecium (59.65%) were the dominant species. Resistance to linezolid, ciprofloxacin, erythromycin, gentamicin, vancomycin, rifampicin, and tetracycline was prevalent. Fifty (50) strains tested positive for class 1 integron, more frequent in Enterococcus faecium and Enterococcus faecalis isolates, with no gene cassette array discovered. A combination of gentamicin (MIC 4 µg/mL) with vancomycin (MIC 256 µg/mL) antibiotics against Enterococcus faecalis showed antibacterial activity. In contrast, the combination of ciprofloxacin (1 µg/mL) with Ampicillin (16 µg/mL) antibiotics against Enterococcus faecalis showed a bacteriostatic effect. The ERIC-PCR analysis pointed out that most of the assessed isolates have close genetic similarities.Item Antibiotic resistance and virulence genes profiling of Vibrio cholerae and Vibrio mimicus isolates from some seafood collected at the aquatic environment and wet markets in Eastern Cape Province, South Africa(Public Library of Science, 2023-08-24) Abioye, Oluwatayo E.; Nontongana, Nolonwabo; Osunla, Charles A.; Okoh, Anthony Ifeanyi; Venkitanarayanan, K.The current study determines the density of Vibrio spp. and isolates V. cholerae and Vibrio mimicus from fish-anatomical-sites, prawn, crab and mussel samples recovered from fish markets, freshwater and brackish water. Virulence and antibiotic resistance profiling of isolates were carried out using standard molecular and microbiology techniques. Vibrio spp. was detected in more than 90% of samples [134/144] and its density was significantly more in fish than in other samples. Vibrio. cholerae and V. mimicus were isolated in at least one sample of each sample type with higher isolation frequency in fish samples. All the V. cholerae isolates belong to non-O1/non-O139 serogroup. One or more V. cholerae isolates exhibited intermediate or resistance against each of the eighteen panels of antibiotics used but 100% of the V. mimicus were susceptible to amikacin, gentamycin and chloramphenicol. Vibrio cholerae exhibited relatively high resistance against polymyxin, ampicillin and amoxicillin/clavulanate while V. mimicus isolates exhibited relatively high resistance against nitrofurantoin, ampicillin and polymixin. The multiple-antibiotic-resistance-index [MARI] for isolates ranges between 0 and 0.67 and 48% of the isolates have MARI that is >0.2 while 55% of the isolates exhibit MultiDrug Resistance Phenotypes. The percentage detection of acc, ant, drf18, sul1, mcr-1, blasvh, blaoxa, blatem, blaoxa48, gyrA, gyrB and parC resistance-associated genes were 2%, 9%, 14%, 7%, 2%, 25%, 7%, 2%, 2%, 32%, 25% and 27% respectively while that for virulence-associated genes in increasing other was ace [2%], tcp [11%], vpi [16%], ompU [34%], toxR [43%], rtxC [70%], rtxA [73%] and hyla [77%]. The study confirmed the potential of environmental non-O1/non-O139 V. cholerae and V. mimicus to cause cholera-like infection and other vibriosis which could be difficult to manage with commonly recommended antibiotics. Thus, regular monitoring of the environment to create necessary awareness for this kind of pathogens is important in the interest of public health.Item Occurrence of virulence determinants in vibrio cholerae, vibrio mimicus, vibrio alginolyticus, and vibrio parahaemolyticus isolates from important water resources of Eastern Cape, South Africa(BioMed Central, 2023-10-23) Abioye, Oluwatayo E.; Osunla, Charles A.; Nontongana, Nolonwabo; Okoh, Anthony IfeanyiBackground: Virulence determinants are crucial to the risk assessment of pathogens in an environment. This study investigated the presence of eleven key virulence-associated genes in Vibrio cholerae (n=111) and Vibrio mimicus (n=22) and eight virulence determinants in Vibrio alginolyticus (n=65) and Vibrio parahaemolyticus (n=17) isolated from six important water resources in Eastern Cape, South Africa, using PCR techniques. The multiple virulence gene indexes (MVGI) for sampling sites and isolates as well as hotspots for potential vibriosis outbreaks among sampling sites were determined statistically based on the comparison of MVGI. Result: The PCR assay showed that all the V. cholerae isolates belong to non-O1/non-O139 serogroups. Of the isolates, Vibrio Cholera (84%), V. mimicus (73%), V. alginolyticus (91%) and V. parahaemolyticus (100%) isolates harboured at least one of the virulence-associated genes investigated. The virulence gene combinations detected in isolates varied at sampling site and across sites. Typical virulence-associated determinants of V. cholerae were detected in V. mimicus while that of V. parahaemolyticus were detected in V. alginolyticus. The isolates with the highest MVGI were recovered from three estuaries (Sunday river, Swartkopps river, buffalo river) and a freshwater resource (Lashinton river). The cumulative MVGI for V. cholerae, V. mimicus, V. alginolyticus and V. parahaemolyticus isolates were 0.34, 0.20, 0.45, and 0.40 respectively. The targeted Vibrio spp. in increasing order of the public health risk posed in our study areas based on the MVGI is V. alginolyticus>V. parahaemolyticus>V. cholerae>V. mimicus. Five (sites SR, PA5, PA6, EL4 and EL6) out of the seventeen sampling sites were detected as the hotspots for potential cholera-like infection and vibriosis outbreaks. Conclusions: Our findings suggest that humans having contact with water resources in our study areas are exposed to potential public health risks owing to the detection of virulent determinants in human pathogenic Vibrio spp. recovered from the water resources. The study affirms the relevancy of environmental Vibrio species to the epidemiology of vibriosis, cholera and cholera-like infections. Hence we suggest a monitoring program for human pathogenic Vibrio spp. in the environment most especially surface water that humans have contact with regularly