Jacobus Nicolaas Eloff

University of Pretoria | UP · Department of Paraclinical Sciences

Background: Antioxidants present in plant extracts prevent free radicals from causing chronic diseases in humans. Aim: The study investigated 12 medicinal plants ( Kleinia longiflora DC., Berchemia discolor [Klotzsch] Hemsl., Persea americana Mill., Sansevieria hyacinthoides [L.] Druce, Dichrostachys cinerea [L.] Wright &Arn, Withania somnifera Dun...

Phytopathogenic fungi and nematodes cause great losses in economically important crops and food production especially in developing countries. To minimize the use of fungicides and nematicides, researchers have concentrated on the use of natural products for crop disease prevention or control. The aim of the study was to investigate the antifungal...

Background: Lonchocarpus capassa is a medicinal plant used to treat diseases such as fungal infections, diarrhoea, oral candidiasis, and stomach complaints in South Africa. Aim: The study aimed to investigate the cytotoxicity and antifungal compounds isolated from L. capassa leaf extracts. Setting: The study was conducted in Muduluni village, Makha...

Black locust (Robinia pseudoacacia L.), an invasive tree in Europe, commonly known for its negative impact on biodiversity, is a rich source of phenolic compounds recognized in traditional medicine. Since the metabolite profile depends on the environment and climate, this study aimed to provide the first LC-MS phytochemical screening of the black l...

Background Psilocybin-containing mushrooms induce antidepressant and momentary increase in blood pressure (BP) with potential risk to users with cardiovascular diseases. Irregularities in nitric oxide (NO) levels play a key role in endothelial dysfunctions leading to increases in BP. Mushrooms species show large variation in potency which may poten...

Psilocybin-containing mushrooms, commonly known as magic mushrooms have antidepressant effect, however, their safety in cardiovascular diseases such as heart failure is not fully known and needs to be investigated. Cardiac hypertrophy is an independent risk factor for heart failure morbidity and mortality. Angiotensin II (Ang-II) plays a major role...

Quantification of compounds in plant extracts is rarely conducted to determine variation in concentrations of bioactive constituents. The aim of the study was to develop a method using ultra-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) to identify and quantify obliquumol (12-O-acetylptaeroxylinol) in Ptaeroxylon obliquum...

Several cancers are induced by microbial infections or chronic inflammation. Ptaeroxylon obliquum is traditionally used to treat various infections characterized by inflammation. The in vitro antiproliferative and antioxidant activity of P. obliquum leaf extracts, fractions and isolated compounds were determined. Antiproliferative activity was asse...

Ethnopharmacological relevance Lichens, a unique symbiotic association between an alga/cyanobacterium and a fungus, produce secondary metabolites that are a promising source of novel drug leads. The beauty and importance of lichens have not been adequately explored despite their manifold biological activities such as anticancer, antimicrobial, anti...

Ptaeroxylon obliquum is used traditionally to treat inflammatory diseases and related symptoms such as arthritis, rheumatism, fever and headache. The aim of the study was to determine the anti-inflammatory activities of the crude extracts, fractions and isolated compounds from P. obliquum leaves. Nitric oxide (NO) production in lipopolysaccharide (...

Background Previous studies in our laboratory in ex vivo assays have demonstrated H. hemerocallidea extract as potential antidiabetic agent through increased insulin release from pancreatic beta cells. Thus, for this study the early stage type II spontaneous diabetic mutant mice model was used to evaluate and determine the degree of the antidiabeti...

Invasive plants’ phytochemicals are important for their invasiveness, enabling them to spread in new environments. However, these chemicals could offer many pharmaceutical compounds or active ingredients for herbal preparations. This study provides the first LC–MS phytochemical screening of six invasive alien plant species (IAPS) in the Istria regi...

Inflammation is an important component of the immune response to pathogens and damaged cells. This study aims to assess and compare of anti-inflammatory activities in-vitro and in-silico of essential oils from galls formed on leaves of Pistacia atlantica Desf from two regions in Algeria (four samples from Ain-oussera and four samples from Laghouat)...

Ethnobotanical relevance Smoke from the wood of Acacia seyal Delile has been used by Sudanese women for making a smoke bath locally called Dukhan. The ritual is performed to relieve rheumatic pain, smooth skin, heal wounds and achieve general body relaxation. Aim of the study The present study was designed to investigate the in vitro anti-inflamma...

Psilocybin-containing mushrooms, commonly known as magic mushrooms, have been used since ancient and recent times for depression and to improve quality of life. However, their anti-inflammatory properties are not known. The study aims at investing cytotoxicity; antioxidant; and, for the first time, anti-inflammatory effects of Psilocybe natalensis,...

Cattle are a livelihood asset to smallholder farmers in Africa yet remain threatened by the effects of ticks and tick-borne diseases during production because they cause morbidity and premature death. The use of indigenous plants in tick control is a worldwide practice spanning thousands of years. Changes in the agricultural and socio-cultural land...

Purpose During a pathological inflammation, macrophages are activated to produce accumulation of inflammatory mediators such as induced-cyclooxygenase-2 (COX-2), 15-lipoxygenase (15-LOX) and pro-inflammatory cytokines. Pathological inflammation is a significant problem in many chronic diseases. As a result, more research into natural remedies with...

Ethnopharmacological relevance: Ptaeroxylon obliquum (Thunb.) Radlk, sneezewood, is a commonly used medicinal plant in South Africa for the treatment of parasitic infections in animals, tuberculosis (TB) and related symptoms, and other microbial infections. Aim of the study: In this study, anthelmintic, antifungal, antimycobacterial, larvicidal...

Many scientists investigate the potential of finding new antibiotics from plants, leading to more than a thousand publications per year. Many different minimum inhibitory concentrations of extracts have been proposed to decide if an extract has interesting activity that could lead to the discovery of a new antibiotic. To date, no rational explanati...

Background: Some viruses play a key role in the disturbance of the digestive system. The common viruses which cause infectious diarrhoea (gastroenteritis) include astrovirus, caliciviruses, coronavirus and torovirus which are single-stranded RNA viruses. Influenza A virus (H1N1) also causes diarrhoea in addition to being associated with respirator...

Abstract Prevalence of major depression in people with chronic heart failure is higher than in normal populations. Depression in heart failure has become a major issue. Psilocybin-containing mushrooms commonly known as magic mushrooms, have been used since ancient times for their mind healing properties. Their safety in cardiovascular disease condi...

Background Diarrhoea is a major health issue in both humans and animals and may be caused by bacterial, viral and fungal infections. Previous studies highlighted excellent activity of Newtonia buchananii and N. hildebrandtii leaf extracts against bacterial and fungal organisms related to diarrhoea-causing pathogens. The aim of this study was to iso...

The ability to block human-to-mosquito and mosquito-to-human transmission of Plasmodium parasites is fundamental to accomplish the ambitious goal of malaria elimination. The WHO currently recommends only primaquine as a transmission-blocking drug but its use is severely restricted by toxicity in some populations. New, safe and clinically effective...

Background Antibiotics are commonly added to livestock feeds in sub-therapeutic doses as growth promoters and for prophylaxis against pathogenic microbes, especially those implicated in diarrhoea. While this practice has improved livestock production, it is a major cause of antimicrobial resistance in microbes affecting livestock and humans. This h...

Psilocybin-containing mushrooms, commonly known as magic mushrooms, have been used since ancient and recent times for depression and to improve quality of life. However, their anti-inflammatory properties are not known. The study aims at investing cytotoxicity; antioxidant; and, for the first time, anti-inflammatory effects of Psilocybe natalensis,...

This study reports the first total synthesis of the bioactive oxepinochromones 12-O-acetyleranthin (8) (angular isomer) and 12-O-acetylptaeroxylinol (9) (linear isomer). The antifungal activity of these compounds and their derivatives was determined against Candida albicans and Cryptococcus neoformans. Most compounds had good selectivity between th...

Hypoxis hemerocallidea is wild harvested and widely used due inter alia to its strong antioxidant activity. Antioxidant activity is linked to plant stressors like soil heavy metals concentrations and pH. If high antioxidant activity is caused by heavy metals stressing the plant, the plant may not be completely safe. Soils and H. hemerocallidea corm...

Anthrax, a zoonotic disease and a potential biological weapon for terrorism is caused by Bacillus anthracis , a Gram‐positive, sporulating bacterium. Anthrax is endemic in South Africa and primarily affects livestock and wildlife species. Problems with the control of anthrax include growing resistance to present antibiotics and disinfectants or dec...

Aspergillosis is an opportunistic airborne fungal infection caused by ubiquitous saprophytic moulds of the Aspergillus genus. Infection has been documented in humans and animals, and it usually occurs through inhalation of unicellular spores known as conidia or, more rarely, after ingestion or wound contamination. Oral candidiasis is also an import...

Background Antibiotics are commonly added to livestock feeds in sub-therapeutic doses as growth promoters and for prophylaxis against pathogenic microbes, especially those implicated in diarrhoea. While this practice has improved livestock production, it is a major cause of antimicrobial resistance in microbes against livestock and humans. This has...

Background Antibiotics are commonly added to livestock feeds in sub-therapeutic doses as growth promoters and for prophylaxis against pathogenic microbes, especially those implicated in diarrhoea. While this practice has improved livestock production, it is a major cause of antimicrobial resistance in microbes against livestock and humans. This has...

Background: Influenza A virus (IAV) is still a major health threat. The clinical manifestations of this infection are related to immune dysregulation, which causes morbidity and mortality. The usage of traditional medication with immunomodulatory properties against influenza infection has been increased recently. Our previous study showed antivira...

Background: Many studies have revealed that bioactive compounds for different indications are not extracted from plants with water, the only extractant practically available to rural communities. We compared the acaricidal activity of acetone extracts of 13 species used traditionally to protect cattle against ticks. We also investigated if the ext...

Ptaeroxylon obliquum (Thunb.) Radlk. (Rutaceae) is traditionally used to treat human and animal diseases in South Africa. In this study, the activity of leaf extracts, fractions, and isolated compounds was determined against nonpathogenic mycobacterial species and nosocomial bacterial pathogens. An acetone leaf extract was partitioned by liquid-liq...

Ptaeroxylon obliquum (Thunb.) Radlk. (Rutaceae) is traditionally used to treat human and animal diseases in South Africa. In this study, the activity of leaf extracts, fractions, and isolated compounds was determined against nonpathogenic mycobacterial species and nosocomial bacterial pathogens. An acetone leaf extract was partitioned by liquid-liq...

Plant extracts used for the treatment of helminth infections in sheep are an alternative to chemical anthelmintic drugs. Previous studies have reported the anthelmintic activity of acetone leaf extracts of Leucosidea sericea. For this study, we evaluate the ultrastructure changes induced by the acetone leaf extract of L. sericea and the component a...

Background: Antibiotics are commonly added to livestock feeds in sub-therapeutic doses as growth promoters and for prophylaxis against pathogenic microbes, especially those implicated in diarrhoea. While this practice has improved livestock production, it is a major cause of antimicrobial resistance in microbes against livestock and humans. This ha...

Hot water and hydroethanolic (70:30) extracts were prepared from 15 plant species, which were investigated to discover eco-friendly and less expensive tick control methods as an alternative to synthetic acaricides. A contact bioassay was used to determine the acaricidal activity of these extracts against the cattle tick, Rhipicephalus turanicus (Ac...

Some traditional healers believe that cultivated medicinal plants are not as active as plants collected from nature that may be growing under more environmental stress. This perception has implications for the conservation of popular medicinal plants. We previously found that water stress on plants had a limited effect on antimicrobial activity of...

Bauhinia galpinii N. E. Br is a shrub or small tree that grows 3–9 m tall throughout South Africa in nature and as ornamental plant. Various parts of the plant are used to cure gastrointestinal tract (GIT) disorders, epilepsy, convulsion, infertility, and amenorrhoea. Despite popular use, the phytochemicals responsible for the medicinal efficacy of...

Combretum molle occurs widely in Africa and is used traditionally to treat many different ailments including microbial infections. Some work has been done on the antimicrobial activity of bark extracts, but not on leaf extracts, a sustainable resource. Dried ground leaves were extracted with methanol, butanol, acetone, ethyl acetate, chloroform, di...

Background Antimicrobial resistance (AMR) remains an important global health issue but the gap between AMR and development of new antimicrobials is increasing. Plant extracts may have good activity per se or may be sources of effective antimicrobial compounds which can act against planktonic and/or biofilms of pathogens. We determined the antimicro...

Background: There is an urgent need to discover new antimicrobial compounds or extracts to address the crucial problem of increasing microbial resistance against current antibiotics. Plant chemical biodiversity is a valuable potential resource. Although compounds from plants are used as basis for several human drugs, no commercially successful ant...

Background Diarrhoea, a global economically important disease burden affecting swine and, especially piglets, is commonly caused by infection with entero-toxigenic E. coli (ETEC). Adherence of ETEC to porcine intestinal epithelial cells following infection, is necessary for its pathogenesis. While antimicrobials are commonly given as therapy or as...

Background Tuberculosis is a deadly disease caused by Mycobacterium species. The use of medicinal plants is an ancient global practice for the treatment and prevention of diverse ailments including tuberculosis. The aim of this study was to isolate and characterize antimycobacterial compounds by bioassay-guided fractionation of the acetone leaf ext...

Background Rotheca glabrum (formerly known as Clerodendrum glabrum [Verbenaceae]) is used by local communities in the Limpopo Province of South Africa to control ticks on livestock and was selected from the database of the ARC-Onderstepoort Veterinary Institute. Its leaves were extracted using organic solvents ranging from polar to non-polar solven...

Abstract Background Optimal adoption of the malaria transmission-blocking strategy is currently limited by lack of safe and efficacious drugs. This has sparked the exploration of different sources of drugs in search of transmission-blocking agents. While plant species have been extensively investigated in search of malaria chemotherapeutic agents,...

Extracts of many plant species have substantial antifungal activity, therefore the use of plant extracts with good activity against plant fungal pathogens could lead to the development of inexpensive and environmentally acceptable fungicides based on locally available natural products. Because large quantities of invasive weeds are available we dec...

Background: Croton species (Euphorbiaceae) are distributed in different parts of the world, and are used in traditional medicine to treat various ailments including cancer, inflammation, parasitic infections and oxidative stress related diseases. The present study aimed to evaluate the antioxidant, anti-inflammatory and cytotoxic properties of dif...

The prevalence of antibiotic residues in animal edible products such as meat and egg and the consequent potential for transmission of antibiotic resistant pathogens to human consumers poses a global food safety and health concerns. Amidst other management methods, antibiotics are given therapeutically or added to livestock feeds to promote growth a...

The prevalence of antibiotic residues in animal edible products such as meat and egg and the consequent potential for transmission of antibiotic resistant pathogens to human consumers poses a global food safety and health concerns. Amidst other management methods, antibiotics are given therapeutically or added to livestock feeds to promote growth a...

Diarrhoea is one of the most serious impediments to the swine industry globally, causing huge annual economic losses, reduced growth rates and high treatment costs. Enterotoxigenic E. coli (ETEC) accounts mostly for neonatal and post-weaning diarrhoea in piglets, and the onset of its pathogenesis is mostly via adherence and colonization of enterocy...

The menace caused by ticks and tick-borne diseases is a major limitation to the livestock industry in Africa. The high costs and non-availability of synthetic, chemical acaricides to resource-limited farmers, resistance of ticks to available acaricides and residue problems in meat and milk consumed by humans further complicate matters. The use of p...

Ticks are a large group of parasitic arthropods which transmit pathogens to animals and humans, causing great economic losses. Chemical-based antitick measures include the use of pyrethroids, carbamates, organophosphates, formamidines and macrocyclic lactones, which all have associated costs, resistance-development and environmental hazards. Some p...

Background: Influenza infection is a major public health threat. The role of influenza A virus-induced inflammatory response in severe cases of this disease is widely recognized. Drug resistance and side effects of chemical treatments have been observed, resulting in increased interest in alternative use of herbal medications for prophylaxis again...