Research Articles (Paraclinical Sciences)

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Investigation of the antimycobacterial activity of African medicinal plants combined with chemometric analysis to identify potential leads
(Nature Research, 2024-06-25) Moyo, Phanankosi; Ofori, Michael; Bodede, Olusola S.; Wooding, Madelien; Khorommbi, Ndivhuwo Kevin; McGaw, Lyndy Joy; Danquah, Cynthia A.; Maharaj, Vinesh J.; vinesh.maharaj@up.ac.za
The emergence of drug-resistant Mycobacterium tuberculosis strains is a threat to global health necessitating the discovery of novel chemotherapeutic agents. Natural products drug discovery, which previously led to the discovery of rifamycins, is a valuable approach in this endeavor. Against this backdrop, we set out to investigate the in vitro antimycobacterial properties of medicinal plants from Ghana and South Africa, evaluating 36 extracts and their 252 corresponding solid phase extraction (SPE) generated fractions primarily against the non-pathogenic Mycobacterium smegmatis and Mycobacterium aurum species. The most potent fraction was further evaluated in vitro against infectious M. tuberculosis strain. Crinum asiaticum (bulb) (Amaryllidaceae) emerged as the most potent plant species with specific fractions showing exceptional, near equipotent activity against the non-pathogenic Mycobacterium species (0.39 µg/ml ≤ MIC ≤ 25 µg/ml) with one fraction being moderately active (MIC = 32.6 µg/ml) against M. tuberculosis. Metabolomic analysis led to the identification of eight compounds predicted to be active against M. smegmatis and M. aurum. In conclusion, from our comprehensive study, we generated data which provided an insight into the antimycobacterial properties of Ghanaian and South African plants. Future work will be focused on the isolation and evaluation of the compounds predicted to be active.
Soil and cattle health : is there an association?
(Plaas Media, 2025) Myburgh, Jan G.; jan.myburgh@up.ac.za
Crop producers in general understand the value of soil that is healthy (soil biology), and the last decade or two has seen numerous producers starting to apply regenerative farming principles. Crop farming methods that improve soil biology are well-known.
The effects of postnatal exposure to di-n-butyl phthalate (DBP) on the male reproductive system in animals : a systematic review and meta-analysis
(Elsevier, 2025-06) Ibrahim, Mohammed I.A.; Ahmed, Osman Merghani Makki; Botha, C.J. (Christo J.); u17372098@tuks.co.za
Di-n-butyl phthalate (DBP) is a ubiquitous environmental contaminant widely used in personal care products and medical products, causing male reproductive toxicity in humans and animals following exposure. It has endocrine-disruptive activities, causing adverse effects on the male reproductive system. This study aimed to investigate the male reproductive injury induced by DBP in animals. We conducted a systematic review and meta-analysis of the related literature captured in Google Scholar, MEDLINE, Scopus, PubMed and Web of Sciences databases. This review included animal studies that were postnatally exposed to DBP. After applying the inclusion and exclusion criteria, a total of 48 relevant studies were selected, which included studies in rats (n = 29), mice (n = 5), rabbits (n = 3), birds (n = 6), and fish (n = 5) exposed to DBP. The scope of the study included testicular and epididymal morphology, sperm quality and oxidative stress parameters, steroidogenic enzymes, and sex steroid hormones. The meta-analysis focused on rat studies, which revealed a significant decrease in sperm count (p < 0.001), sperm motility (p < 0.001), superoxide dismutase (SOD, p < 0.001) activity and testosterone (p < 0.001) concentration. Moreover, DBP exposure significantly increased sperm abnormality (p < 0.001), catalase (CAT; p = 0.003) activity and malondialdehyde (MDA; p < 0.001) levels. Postnatal exposure to 1 mg/kg DBP could decrease the sperm count, sperm motility, testosterone concentration, and SOD activity by 5.87 %, 0.17, 7.46 % and 21.38 %, respectively. As a result of the meta-analysis, SOD activity was more sensitive to DBP following postnatal exposure than CAT activity or MDA levels, while sperm abnormality was less susceptible than sperm count and sperm motility to DBP exposure. Generally, the systematic review and meta-analysis demonstrated that postnatal exposure to DBP-induced male reproductive injury by inducing oxidative stress and altering steroidogenesis, and sex hormones in animals. Moreover, the review identified important gaps in animal studies of dermal exposure to DBP, emphasizing the need for further research to assist in conducting more rigorous epidemiological and risk assessment studies that represent real-life exposure scenarios.
The history and future of the South African Association of Botanists and the South African Journal of Botany
(Elsevier, 2025-07) Eloff, Jacobus Nicolaas; Balkwill, Kevin
In 1913, two Botanical Institutions developed from two foci in South Africa: the privately funded National Botanical Gardens (NBG) developed in Kirstenbosch and the government funded Botanical Research Institute (BRI — then the Division of Botany) in Pretoria. Both organisations started journals: the Memoirs of the Botanical Survey of South Africa in 1919, Flowering Plants of South Africa in 1920 and Bothalia in 1921 by BRI and the Journal of South African Botany (JSAB) by NBG in 1935. In 1968, the botanical community of South Africa formed the South African Association of Botanists (SAAB) to collectively address the professional needs of botanists. In response to a government initiative, the South African Journal of Botany (SAJB) was launched in 1982 with the support of SAAB. From 1985, the JSAB and SAJB were united under the name of the latter, but continuing the numbering of the former (i.e. from Volume 51). In 2005, SAAB agreed with Elsevier that they would publish the South African Journal of Botany on behalf of SAAB. This arrangement and the efforts of the then Editor-in-Chief, Prof J. van Staden, led to the journal becoming a financial asset to SAAB and to it growing in size and international stature. As long as the arrangement with Elsevier remains favorable and persists, the future of the South African Journal of Botany is positive. The good governance guided by a wise constitution and the astute financial discipline of SAAB have secured the future and sustainability of SAAB and will assist the Association to live up to its Mission Statement. HIGHLIGHTS • Two Botanical Institutions launched South African Botanical journals. • Two were united as the South African Journal of Botany from 1985. • This journal is now published by an international publisher and publishes many papers and has a respectable journal impact factor. • Management of the journal facilitates a good future. • The South African Association of Botanists (SAAB) was formed in 1968. • The society has good governance and many benefits for student members. • The society has well-managed financial resources. • The future of the Association is secure.
Two point-of-care cardiac Troponin I immunoassays have acceptable analytical performance for the detection of measurands of cardiac Troponin I cardiac muscle homogenates from southern-central black rhinoceros (Diceros bicornis minor) and southern white Rhinoceros (Ceratotherium simum simum)
(Wiley, 2025) Rautenbach, Yolandi; Meyer, Leith Carl Rodney; Goddard, Amelia; Buss, Peter Erik; Hooijberg, Emma Henriette
BACKGROUND : Skeletal and possible cardiac muscle damage has been reported in chemically immobilized and transported African rhinoceros during conservation-related activities. The extent of cardiac muscle injury in these rhinoceros is unknown due to a lack of validated cardiac troponin I (cTnI) assays. However, recently, five human cTnI assays were deemed suitable for analytical validation in African rhinoceros based on cTnI sequencing results. OBJECTIVES : The first objective was to validate two cTnI immunoassay point-of-care analyzers (POCAs) in African rhinoceros and, secondly, to perform quality control (QC) validation for the POCAs. METHODS : Analytical validation of the Stratus CS Acute Care Troponin I cTnI immunoassay and Atellica VTLi high sensitivity cTnI (hs-cTnI) assay was performed using rhinoceros serum samples and species-specific cardiac muscle homogenate. Experiments included precision studies, reportable range, hemoglobin interference studies, recovery studies, and detection limit studies, with results assessed against prescribed total allowable error (TEa) performance goals. Commercial quality control material (QCM) data were used to calculate bias and imprecision for QC validation. RESULTS : Imprecision was acceptable (1.9%-10.3%) and met low cTnI concentration performance goals. Reportable ranges were similar to the manufacturer's specifications. High hemoglobin concentrations in white rhinoceros resulted in a positive bias in the Stratus CS. A simple 13s QC rule using two levels of QCM and a TEa of 70% could be used in both analyzers, except at very low cTnI concentrations in the Atellica VTLi. CONCLUSIONS : Both cTnI POCAs are suitable for use in African rhinoceros, and analytical performance goals for low cTnI concentrations in hs-cTnI assays were met.
Size, scaling, and sexual size dimorphism in wild South African thick-tailed greater galagos (Otolemur crassicaudatus)
(Springer, 2024-12) Leigh, Steven R.; Sauther, Michelle L.; Cuozzo, Frank P.; Tordiffe, Adrian Stephen Wolferstan; Van Wyk, Ilana
The developmental bases of sexual size dimorphism vary across primates, with important implications for understanding the evolution of dimorphism. Here, we explore adult sexual size dimorphism and its developmental bases in Otolemur crassicaudatus. We aim to understand the anatomical pattern of adult sexual size dimorphisms and their developmental bases through allometric analyses of somatometrics. We caught and released wild subadult and adult animals annually at Lajuma Research Centre, South Africa from 2013 to 2023 (excepting 2020), and measured body mass and up to 23 body measurements. Among adults, males (mean body mass = 1242.89 g ± SD = 137.63 g, n = 91 observations of n = 52 individuals) are 1.21 times larger than females (mean body mass = 1027.55 g ± SD = 94.03 g, n = 85 observations of n = 44 individuals), possibly representing the highest body mass sexual dimorphism among extant strepsirrhines. The skeletal system shows limited sexual size dimorphism, suggesting decoupling of body mass size dimorphism and skeletal size dimorphism. Allometries lead to variation in adult sexual size dimorphism throughout the body, with high levels of dimorphism in circumferences, especially in the torso and proximal limb elements. Sexual selection, attributable to some level of intermale competition, probably accounts for sexual size dimorphism in this species. The conservatism of the skeletal system, combined with high body mass size dimorphism, may be related to generalized quadrupedalism and declining rates of leaping through ontogeny in the species. These findings complicate reconstructing and interpreting primate sexual size dimorphism in the fossil record.
Prevalence and determinants of suicidal ideation among South African Health Sciences students at the onset of the COVID-19 pandemic
(Frontiers Media, 2025-03) Seedat, Samhaa; Sengwayo, Muhle; Gani, Salma; Mashego, Lesedi; Ochayon, Jordan; Shepard, Ashleigh; Vergie, Caleb; Masango, Mxolisi Goodwill; Makuapane, Lerato P.; Wagner, Fezile; Wagner, Ryan G.
BACKGROUND : Suicidal ideation is an important mental health concern amongst university students who are exposed to multiple stressors. Furthermore, those studying towards degrees in the field of Health Sciences are exposed to additional and unique stressors. This quantitative cross-sectional study aimed to define the prevalence of suicidal ideation and its determinants amongst undergraduate students within the Faculty of Health Sciences at a large, urban South African University. MATERIALS AND METHODS : An online questionnaire was administered to the 4089 students registered in the Faculty of Health Sciences, with 1211 students submitting responses between March and April 2020. The distribution of this survey coincided with the onset of the national lockdown due to the Covid-19 pandemic. The survey was comprised of validated tools measuring depression (with an included indicator of suicidal ideation), anxiety and resilience. Data analysis was completed using the STATA statistical software (version 14). Both a bivariate analysis and a multivariate logistic regression adjusted for gender were performed. RESULTS : The total prevalence of suicidal ideation adjusted for gender and race in this sample was found to be 21.8% (CI: 18.6-25.3; p<0.001). Females had significantly higher suicidal ideation than males (24.1% versus 17.8%; p=0.011). In the multivariate model adjusted for gender, having depressive (aOR 10.8; CI: 7.9-14.8; p<0.001) or anxiety (aOR 5.1: CI: 3.8-6.8; P<0.001) symptoms, only sometimes (aOR 2.7: CI 1.8-4.0; p<0.001) or never (aOR 2.7; CI: 1.8-4.0; p<0.001) having anyone to talk to and being of colored race (aOR 2.0; CI: 1.1-3.4; p=0.019) were significantly associated with suicidal ideation, whilst higher resilience (aOR 0.3; CI: 0.3-0.4; p<0.001) was associated with lower levels of suicidal ideation. CONCLUSION : The prevalence of suicidal ideation found in this study was higher than that found in the general South African adult population and highlights the need to further investigate and address student mental health, especially students in the field of Health Sciences. Interventions aimed at mitigating the determinants, including depression and anxiety, and promoting the development of protective factors such as resilience and social support may lead to a reduction in suicidal ideation in this population group. Institutional initiatives aimed at improving access to and the quality of mental health services offered to students should be widely advocated for and implemented.
Quorum sensing inhibition by South African medicinal plants species : an in vitro and an untargeted metabolomics study
(BioMed Central, 2025-04) Moyo, Phanankosi; Bodede, Olusola; Wooding, Madelien; Famuyide, Ibukun Michael; Makhubu, Fikile Nelly; Khorommbi, Ndivhuwo Kevin; Ofori, Michael; Danquah, Cynthia A.; McGaw, Lyndy Joy; Maharaj, Vinesh J.
BACKGROUND : The emergence of antimicrobial resistance (AMR) is imperiling global health, hence, the need to remedy this challenge by discovering new therapeutic strategies and agents. Quorum sensing inhibition (QSI) is opined as a potential novel strategic approach in the fight against AMR by abrogation of bacterial virulence and pathogenicity. Currently, there are no clinically approved QSI drugs. Based on this, this study evaluated the QSI properties of South African plant species. METHODS : Twenty-nine extracts and their corresponding 203 fractions generated using solid phase extraction were screened for QSI activity in vitro against Chromobacterium violaceum ATCC 12472. Active and inactive fractions of the most potent plant species were analysed using UPLC-HRMS. The acquired mass spectral data was subjected to chemometric analysis. RESULTS : From the QSI assays, three plant species showed remarkable QSI activity, measured by dose-dependent inhibition of violacein production (IVP), at sublethal concentrations. Terminalia phanerophlebia emerged as the most active species, with the extract and five of its fractions showing good activity in IVP (IVP IC50 ≤ 0.1 mg/mL). This was closely followed by Momordica cardiospermoides whose crude extract and two of its corresponding fractions showed good activity (IVP IC50 ≤ 0.1 mg/mL). Three fractions of Helichrysum odoratissimum also had good activity (IVP IC50 ≤ 0.1 mg/mL) marking it one of the most potent selected species. Chemometric analysis identified five compounds including olivetol and hydroxytyrosol as chemical markers positively associated with the QSI activity of T. phanerophlebia. CONCLUSION : In conclusion, the findings of our study provided insight into the QSI properties of South African plant species. Further studies will focus on the isolation of the putative active compounds and the in vitro evaluation of their QSI activity.
Cardioprotective and renoprotective effects of melatonin and vitamin E on fluoride-induced hypertension and renal dysfunction in rats
(Springer, 2024-02) Oyagbemi, Ademola Adetokunbo; Ajibade, Temitayo Olabisi; Esan, Oluwaseun Olanrewaju; Adetona, Moses Olusola; Awoyomi, Omolola Victoria; Omobowale, Temidayo Olutayo; Ola-Davies, Olufunke Eunice; Saba, Adebowale Benard; Adedapo, Adeolu Alex; Nkadimeng, Sanah Malomile; McGaw, Lyndy Joy; Kayoka-Kabongo, Prudence Ngalula; Yakubu, Momoh Audu; Nwulia, Evaristus; Oguntibeju, Oluwafemi Omoniyi
Fluoride is an important toxicological and environmental toxicant that is implicated in diverse cardiorenal system dysfunctions via the induction of oxidative stress. The present study aims at evaluating the cardioprotective and renoprotective effects of melatonin and vitamin E on fluoride toxicity on biomarkers of oxidative stress, clinical pathology, and their molecular mechanism of action. Apparently healthy male rats of the Wistar strain (n = 50; 160 ± 7.5 g), were randomly distributed into five groups of ten animals per group as follows: Control, sodium fluoride (NaF, 25 mg/kg), NaF and melatonin 20 mg/kg i.p.; NaF and vitamin E 50 mg/kg p/o, NaF plus melatonin and vitamin E administered orally. NaF and melatonin were administered for fifteen consecutive days, whereas vitamin E was administered every 72 h. Blood pressure parameters, oxidative stress biomarkers, electrocardiography, histopathology, and immunohistochemical staining were performed. From this study, NaF intoxication provoked reduction in renal and cardiac systemic antioxidants, alterations of haemodynamic and electrocardiographic parameters, heightened blood urea nitrogen (BUN), creatinine, angiotensin converting enzyme, angiotensin 2 type 1 receptor, kidney injury molecule 1, interleukin 1 beta in the renal tissues, cardiac troponin, and nuclear kappa beta. However, the administration of either melatonin or vitamin E, and its combination mitigated high blood pressure, normalized electrocardiographic changes, abrogated biomarkers of oxidative stress, improved renal function, and attenuated inflammation. The combination of melatonin and vitamin E effectively mitigated cardiovascular and renal toxicities associated with fluoride intoxication through the prevention of cardio-renal dysfunction, oxidative stress, and inflammatory processes.
Sex-dependent metabolic and behavioural alterations in a rat model of forced exertion-induced myopathy
(BioMed Central, 2025-03) Lubbe, Crystal; Harvey, Brian H.; Viljoen, Francois P.; Meyer, Leith Carl Rodney; Wolmarans, De Wet
Please read abstract in the article.
Acute animal toxicity and genotoxicity of obliquumol, a potential new framework antifungal compound isolated from Ptaeroxylon obliquum (Rutaceae) leaf extracts
(Elsevier, 2024-09) Ramadwa, Thanyani Emelton; McGaw, Lyndy Joy; Madikizela, Balungile; Eloff, Jacobus Nicolaas
Obliquumol (12-O-acetylptaeroxylinol) isolated from Ptaeroxylon obliquum leaves has excellent antifungal activity and low cellular toxicity. As a next step in the potential development of a framework antifungal product, the present work investigated the acute animal toxicity of obliquumol according to OECD 423 guidelines. Furthermore, the genotoxicity of P. obliquum acetone leaf extracts, fractions (hexane, chloroform and 30 % H2O in MeOH) and isolated compounds (obliquumol and a mixture of lupeol and β-amyrin) was determined using Ames test. . A single dose of obliquumol was orally administered to mice at levels of 50, 300 and 2000 mg/kg and observed for 14 days. The three S. typhimurium tester strains TA 98, TA 100 and TA 102 were used without metabolic activation to determine the genotoxicity. Even at the highest dose of obliquumol, the mass, behaviour and food intake of the animals were not affected. Gross necropsy and histopathological analysis on organs indicated hardly any effects. No samples had genotoxic activity against the S. typhimurium strains tested. Obliquumol had an LD50 >2000 mg/kg since there were no mortalities after 14 days. This encourages the possible development of a new class of antifungal compounds from the obliquumol framework.
Yellow fever in non-human primates : a veterinary guide from a One Health perspective
(MDPI, 2025-04) Nederlof, Remco A.; Virgilio, Tommaso; Stemkens, Hendrickus J.J.; Da Silva, Luiz C.C. Pereira; Montagna, Daniela R.; Abdussamad, Abdussamad M.; Chipangura, John Kudakwashe; Bakker, Jaco; john.chipangura@up.ac.za
SIMPLE SUMMARY : Yellow fever (YF) is a serious viral arthropod-borne disease in Africa and South America, affecting both humans and non-human primates (NHPs). The susceptibility of different NHP species to YF varies greatly, with the largest mortality events reported in howler monkeys (genus Alouatta). Neotropical primates (NTPs) often show non-specific clinical signs, if any, before dying. These outbreaks in NTPs may be used to signal potential outbreaks in humans. For these early warning systems to be effective, accurate and reliable diagnostic techniques that work under field settings are essential. There are no YF-specific treatments available, but the human 17DD-vaccine effectively prevents the disease in NHPs. Prophylaxis should be based on a One Health perspective that recognizes the intricate interplay between human health, primate health, and the environment. Consequently, mitigation strategies continue to rely more and more on vector control, preferably using eco-friendly methods. Climate change and human activities, along with impact on local ecology, are assumed to increase the risk of YF transmission in the next decades. This underscores the importance of future research, which should focus on refining YF monitoring systems and developing immunization techniques that are applicable to wild NTP populations.
Biosecurity practices in Portuguese small ruminant farms : current status and future directions
(MDPI, 2025-04) Alavedra, Maria; Moura, Dina; Cenci-Goga, Beniamino T.; Saraiva, Sonia; Silva, Filipe; Pires, Isabel; Saraiva, Cristina; Coelho, Ana Claudia; Garcia-Diez, Juan
SIMPLE SUMMARY : Biosecurity is crucial in livestock farming to prevent the spread of disease, ensure animal welfare, and maintain sustainability. In Portugal, small ruminant production is predominantly extensive, small-scale, and family-run. This study assessed biosecurity on 276 farms through a cross-sectional survey (July 2023 to April 2024), analyzing compliance with nine biosecurity categories. The results showed low implementation of key measures such as cleaning, disinfection, quarantine, and visitor control. Poor infrastructure further hampered disease prevention. Factors affecting compliance included farmers’ age, education, herd size, and production type, with dairy and larger farms performing best. This study highlights the need for training, veterinary support, and policies to improve biosecurity while maintaining farm viability and protecting public health in rural Portugal.
Anti-biofilm and anti-quorum sensing activities of extract, fractions and compounds from the leaves of Cassia alata L. against yeast pathogens
(Elsevier, 2024-11) Dzoyem, J.P.; Fotso, Simplice Chimi; Wansi, Jean Duplex; Tabenkoueng, Bellier; Tsopgni, Willifred Dongmo Tekapi; Toze, Flavien Aristide Alfred; McGaw, Lyndy Joy; lyndy.mcgaw@up.ac.za
BACKGROUND : Cassia alata or Senna alata, also known as “ringworm bush” because of its very effective fungicidal properties, is commonly used in African traditional medicine to treat fungal infections. Despite extensive phytochemical and pharmacological studies previously reported on C. alata, the antibiofilm activity against pathogenic yeast as well as the related anti-quorum sensing mechanism of some active constituents has not yet been elucidated. The aim of the study was to isolate the bioactive constituents from the methanol extract of the leaves of C. alata (CAExt) using antibiofilm-guided fractionation against yeast fungal pathogens and then to investigate the anti-quorum sensing activity of the active constituents by assessing their ability to inhibit violacein production in Chromobacterium violaceum. METHODS : Chromatographic methods were used to isolate the constituents of CAExt, and spectroscopic methods were used to elucidate the chemical structures of the isolated compounds. The broth microdilution assay was used to evaluate the antifungal activity against Candida albicans and C. parapsilosis, while crystal violet staining was used for the inhibition of biofilm formation and the disruption of preformed biofilm. The biosensor strain C. violaceum ATCC 12472 was used to investigate the anti-quorum sensing activity of the most active constituents. RESULTS : The crude extract exhibited biofilm inhibition and eradication activities against the tested pathogenic yeast. The biofilm inhibition percentages ranged from 53.22 % to 75.38 %, while the biofilm eradication percentages ranged from 23.21 % to 64.25 %. The ethyl acetate fraction demonstrated high biofilm inhibition and eradication activities against the tested microorganisms. The biofilm inhibition percentages ranged from 58.19 % to 79.30 %, while the biofilm eradication percentages ranged from 34.105 % to 69.54 %. The purification of subfractions led to the identification of six compounds: stigmasterol (1), sitosterol (2), lupeol (3), emodin (4), kaempferol (5) and stigmasterol glycoside (6), two of which (4 and 5) showed potent biofilm inhibition and eradication activities. Both compounds demonstrated significantly lower MBIC50 values of 70.81 μg/mL and 65.65 μg/mL against Candida albicans and MBEC50 values of 63.65 μg/mL and 82.66, respectively, against C. albicans and C. parapsilosis. The crude extract and compounds (4) and (5) also demonstrated quorum sensing inhibitory activity, as indicated by the MQSIC value of 1024 μg/mL for the crude extract and 128 μg/mL for the two compounds. Moreover, compounds (4) and (5) displayed significant inhibitory effects on violacein production, as indicated by their low IC50 values of 28.08 μg/mL and 26.44 μg/mL, respectively. CONCLUSIONS : Data obtained in this study not only support the traditional use of C. alata in the treatment of fungal infections but also reveal C. alata extract, as well as the two isolated bioactive compounds emodin (4) and kaempferol (5), as a potential source for developing antibiofilm alternative agents against biofilm-associated yeast infections. LIST OF COMPOUNDS STUDIED : stigmasterol (1), sitosterol (2), lupeol (3), emodin (4), kaempferol (5), stigmasterol glycoside (6)
Does sex matter in the cheetah? Insights into the skeletal muscle of the fastest land animal
(Company of Biologists, 2024-08) Kohn, Tertius Abraham; Knobel, Samantha; Donaldson, Byron; Van Boom, Kathryn Merle; Blackhurst, Dee M.; Peart, James M.; Jensen, Jorgen; Tordiffe, Adrian Stephen Wolferstan
The cheetah is considered the fastest land animal, but studies on their skeletal muscle properties are scarce. Vastus lateralis biopsies, obtained from male and female cheetahs as well as humans, were analysed and compared for fibre type and size, and metabolism. Overall, cheetah muscle had predominantly type IIX fibres, which was confirmed by the myosin heavy chain isoform content (mean±s.d. type I: 17±8%, type IIA: 21±6%, type IIX: 62±12%), whereas humanmuscle contained predominantly type I and IIA fibres (type I: 49±14%, type IIA: 43±8%, type IIX: 7±7%). Cheetahs had smaller fibres than humans, with larger fibres in the males compared with their female counterparts. Citrate synthase (16±6 versus 28±7 μmol min−1 g−1 protein, P<0.05) and 3-hydroxyacyl co-enzyme A dehydrogenase (30±11 versus 47 ±15 μmol min−1 g−1 protein, P<0.05) activities were lower in cheetahs than in humans, whereas lactate dehydrogenase activity was 6 times higher in cheetahs (2159±827 versus 382±161 μmolmin−1 g−1 protein, P<0.001). The activities of creatine kinase (4765±1828 versus 6485 ±1298, P<0.05 μmol min−1 g−1 protein) and phosphorylase (111±29 versus 216±92 μmol min−1 g−1 protein) were higher in humans, irrespective of the higher type IIX fibres in cheetahs. Superoxide dismutase and catalase,markers of antioxidant capacity, were higher in humans, but overall antioxidant capacity was higher in cheetahs. To conclude, fibre type, fibre size andmetabolismdiffer between cheetahs and humans, with limited differences between the sexes.
Influence of tannin-rich extract from commercial Acacia mearnsii and gallocatechin on ovine cryopreserved semen viability
(Taylor and Francis, 2025) Liman, Mohammed S.; Hassen, Abubeker; Smuts, Mario P.; Biraima, Ahmed D.A.; Sutovsky, Peter; McGaw, Lyndy Joy; Holm, Dietmar Erik; dietmar.holm@up.ac.za
The objective of this study was to evaluate the effect of a tannin-rich extract from commercial Acacia mearnsii (MTE_0), and gallocatechin, a flavonoid compound derived from Acacia mearnsii, on the long-term viability and motility of cryopreserved ovine semen. Six fresh ejaculates obtained from six adult merino rams twice per week for three weeks were allocated to five aliquots (0, 12.5, 25, 50, and 100 µM gallocatechin added into the Optidyl™ extender) before cooling and cryopreservation. Effects of MTE_0 and gallocatechin on post-thawed motility characteristics were analyzed using computer-assisted semen analysis (CASA), and viability (LIVE/DEAD® kit, Molecular Invitrogen, Waltham, MA), oxidative stress (2,7-dichlorodihydrofluorescein diacetate (H2DCFDA, Thermo Fisher®, Waltham, MA)) for reactive oxygen species (ROS), mitochondrial membrane potential (JC-1 MitoTracker, Molecular Invitrogen, Waltham, MA), acrosomal integrity (lectin PNA), and capacitation using merocyanine 540 (M540) and YO-PRO-1 dyes in flow cytometry. Data were analyzed using one-way ANOVA (IBM SPSS 21.0 for Windows, Armonk, NY). Gallocatechin at 25 µM positively affected (p ≤ .001) kinematic parameters including average path velocity (VAP), progressive velocity (VSL), and beat cross frequency (BCF) of cryopreserved semen. Similarly, gallocatechin at 25 µM- improved sperm motility (live 21.99 ± 2.06%), reduced ROS levels (26.45 ± 1.10%), and mitigated premature capacitation (viable and stable 20.08 ± 1.48%) compared to other treatments. Gallocatechin addition to semen resulted in a significant (p ≤ .001) positive effect compared with the MTE_0 extract. It is concluded that gallocatechin inclusion at 25 µM significantly reduces semen deterioration following cryopreservation. This study is the first to introduce gallocatechin as an efficient antioxidant additive to ovine semen to improve its quality during storage. Our findings will help improve post-thaw ovine semen quality and longevity. Future studies to elucidate the mechanism of anti-oxidative stress action of gallocatechin and its derivatives on semen motility and longevity are recommended.
Promoting rhinoceros welfare during transit : veterinarians' perspectives on transportation practices
(Medpharm Publications, 2024-11) Macha, E.S.; Meyer, Leith Carl Rodney; Leiberich, Marion; Hofmeyr, M.; Hooijberg, Emma Henriette; emma.hooijberg@up.ac.za
Despite translocation being a useful conservation strategy in rhinoceros management, morbidities and mortalities occurring during transportation pose a significant concern to rhinoceros managers, veterinarians, and scientists. The objectives of this study were to better understand the effects of transport on rhinoceros and to gain insights from veterinarians involved in rhinoceros translocations about current practices and potential interventions that could improve welfare. A weblink and QR code to an online questionnaire with a total of 46 questions in Google Forms was sent to veterinarians who had experience in African rhinoceros transportation, through personal emails and social network forums. Results demonstrated that despite dehydration and negative energy balance being reported as the major causes of morbidities and mortalities during transport and post-release, most veterinarians (30/35; 86%) involved in rhinoceros translocation did not offer water, parenteral fluids, or feed to transported animals, for logistical reasons and the knowledge or perception of rhinoceros' resistance to taking ad lib food and water during transport. However, 52% (15/29) and 41% (15/34) of participants suggested that parenteral fluids could be used as an intervention to mitigate dehydration and negative energy balance respectively. To reduce stress, 94% (33/35) of respondents suggested the use of tranquilisers and sedatives. This study is the first to systematically investigate and report on practices by veterinarians involved in rhinoceros translocations globally. The study highlights that further research is required to explore optimal and pragmatic techniques in the field to mitigate reported welfare challenges in rhinoceros during transport.
Rol van die Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie (SATNT) in die ontginning van die natuurwetenskappe in Afrikaans die afgelope honderd jaar
(Suid Afrikaanse Akademie vir Wetenskap en Kuns, 2025-03) Eloff, Jacobus Nicolaas; kobus.eloff @up.ac.za
Die ontwikkeling van Afrikaans as wetenskapstaal is onder meer te danke aan die ondersteuning van dosente aan veral histories Afrikaanse universiteite, navorsingsrade en staatsdepartemente (byvoorbeeld die vaktaalburo). Die Suid-Afrikaanse Akademie vir Wetenskap en Kuns (SAAWK) het ’n baie belangrike rol gespeel in die ontwikkeling van vakterme en vakwoordeboeke in die natuurwetenskappe en tegnologie. In die biologiese wetenskappe het veral die Potchefstroomse Universiteit vir Christelike Onderwys (tans Noordwes-Universiteit) in vroeër jare en die Universiteit van Pretoria later ’n beduidende rol hierin gespeel. Mediese terme is aanvanklik aan die Universiteit van Stellenbosch en later ook aan die Universiteit van Pretoria ontwikkel. Afrikaanse handboeke by universiteite en skole, ondersteun deur vakwoordeboeke, het beslag gegee aan die nuutgeskepte terminologie. Tot laat in die 1980’s was baie vakverenigings in die natuurwetenskappe tweetalig en aanbiedings by kongresse kon in Afrikaans gelewer word. Met die toename aan histories Afrikaanse universiteite van studente en dosente wat nie Afrikaans kon praat of verstaan nie en die nuwe politieke bedeling ná 1994 het die meeste vakverenigings later slegs Engels gebruik. Nagraadse studente kan nog steeds in Afrikaans voordragte lewer by die studentesimposiums van die SAAWK, maar vir senior navorsers is daar nie veel meer opsies as by die jaarlikse kongresse van die SAAWK, sowel as by Akademia, die nuwe Afrikaanse tersiêre instelling, nie. Vroeër het sommige vaktydskrifte Afrikaanse manuskripte gepubliseer, maar daar is tans prakties net die Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie (SATNT) en LitNet Akademies waar Afrikaanse artikels oor die natuurwetenskappe nog gepubliseer kan word. Die SATNT publiseer al bykans 43 jaar artikels in Afrikaans, maar weens die veranderde politieke omgewing en die gepaardgaande aanpassings aan universiteite se taalbeleide is daar algaande al hoe minder artikels aangebied vir publikasie in die tydskrif. Die lewensbloed vir navorsers in die natuurwetenskappe is die sitasie van publikasies. Daar was ’n groot stryd om ook enkele publikasies in Engels in die SATNT toe te laat. ’n Oplossing is gevind deur die gedrukte kopie slegs in Afrikaans te publiseer, maar voorsiening daarvoor te maak dat Engelse artikels aanlyn ingedien en ook gekeur kan word, maar dat voordat die manuskrip aanvaar word, ’n Afrikaanse taalkundig versorgde manuskrip ingedien moet word. Hierdie benadering blyk ’n wen-wen-oplossing te wees. Om die voortbestaan van die hoër funksies in Afrikaans te bewaar, word geen bladgelde gehef nie en is daar ondersteuning vir taalversorging in Afrikaans beskikbaar deur die SAAWK. Die ontwikkeling van Akademia as Afrikaanse tersiêre instelling in die ooste van Pretoria open opwindende vooruisigte vir die behoud van Afrikaans as wetenskapstaal alhoewel Afrikaans tans steeds as erkende onderrig- en navorsingstaal by die Universiteit Stellenbosch en die Noordwes-Universiteit gebruik word.
Seasonal effects on the fecal microbial composition of wild greater thick-tailed galagos (Otolemur crassicaudatus)
(Springer, 2024-12) Long, Channen; Scheun, Juan; Sauther, Michelle Linda; Cuozzo, Frank P.; Millette, James; Tordiffe, Adrian Stephen Wolferstan
Bacterial communities present in the host digestive tract are important for the breakdown and absorption of nutrients required by the host. Changes in diet and the environment are major factors affecting the composition and diversity of the fecal microbiome. In addition to changes in ambient temperature and rainfall, primates living in seasonal temperate environments also need to adapt to seasonal changes in food resource quantity and quality. However, there is a lack of information about the fecal microbiome in African strepsirrhines relative to other primate taxa. We examined the effects of seasonal dietary and environmental changes on fecal microbial alpha diversity and composition in wild greater thick-tailed galagos (Otolemur crassicaudatus) at Lajuma Research Centre, South Africa. We collected fecal samples and assessed food availability and weather in summer and winter across 1 year and used 16S rRNA next-generation sequencing to characterise the fecal microbiome of 49 animals. We found significant increases in rainfall, ambient temperature, and food availability in summer compared with winter. However, we found no significant changes in body mass or in the overall diversity of bacterial species present in fecal samples between the two seasons. We found significant decreases in the abundance of certain bacterial families in winter, suggesting a change in diet. Our findings suggest that greater thick-tailed galagos can find food resources to maintain their body mass throughout the year. Our insights into the seasonal fecal microbiome of greater thick-tailed galagos add to the growing knowledge and understanding of fecal microbiomes in primates and how they help primates cope with changes to their environments.
A review of health benefits of selected South African indigenous fruits and vegetables
(Elsevier, 2025-04) Netshiluvhi, Thiambi R.; Eloff, Jacobus Nicolaas; kobus.eloff@up.ac.za
Recent studies have indicated that South African diets from conventional food sources frequently lack balanced nutrition which has led to poor health and wellbeing of local communities. Therefore, the purpose of this review was to establish potential health benefits of indigenous fruits and vegetables to address risks of nutritional deficiencies, chronic diseases, and pathogenic infections. Google Scholar, ScienceDirect, and ResearchGate databases were used to find relevant articles from which to identify promising indigenous fruit trees and vegetables. Most fruits (Adonsonia digitata, Vangueria infausta, Parinari. curatellifolia, Strychnos species, Sclerocarya birrea, etc.) and vegetables (Solanum nigrum, Momordica foetida, Vigna subterranean, Amaranthus species, Bidens pilosa, Abelmoschus esculentus, Cucurbita species, etc.) had high concentration levels of dietary fibres, vitamins (A, B1, B2, B3, B9, C, E), and minerals (Zinc, copper, manganese, magnesium, and selenium). Some of the indigenous crops had higher concentration levels of vitamins (A, C), iron, and calcium than those of commercialised fruits or vegetables. As such, those indigenous crops could easily meet or exceed recommended daily allowances of various nutrients. The same indigenous crops also had an array of secondary metabolites such as polyphenols (phenolic acids, flavonoids, tannins, coumarins), polysaccharides, alkaloids, saponins, anthraquinones, coumarins, carotenoids, glycosides, quercetin, kaempferol, phytic acids, and linoleic acids. Dietary fibres, nutrients, and secondary metabolites exhibited antioxidant, anti-inflammatory, immunomodulatory, and antimicrobial properties, which could play a critical role in the prevention and treatment of nutrient deficiencies, chronic diseases, and pathogenic infections. The therapeutic potential of nutrients and secondary metabolites may necessitate those food plants to be classified as nutraceuticals or functional foods. Since results were mostly based on in vitro and animal-based in vivo studies, clinical tests should be undertaken to establish efficacy and safety of dietary fibres, phytonutrients, and secondary metabolites based on optimal human dosages.

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