Weiyang Chen

• PhD
• Tshwane University of Technology

Propolis, a resin‐like substance produced by bees, has previously shown antimicrobial activity against the ulcer‐causing gut pathogen, Helicobacter pylori. South African propolis, however, was yet to be investigated. This study aimed to investigate a comprehensive range of South African propolis for its antimicrobial activity against H. pylori and...

The stem-bark of Prunus africana (Hook.f.) Kalkman (African cherry) is traditionally used for the treatment of stomach ache, chest pain, malaria, fever, diabetes and high blood pressure. A large number of constituents have been isolated from the stem-bark including β-sitosterol and ursolic acid, which were reported to have anti-inflammatory activit...

The intranasal route of drug administration offers an opportunity to bypass the blood–brain barrier and deliver compounds directly into the brain. Scientific evidence exists for medicinal plants (e.g., Centella asiatica and Mesembryanthemum tortuosum) to treat central nervous system conditions such as anxiety and depression. The ex vivo permeation...

Prunus africana (Hook.f.) Kalkman (Rosaceae), commonly known as ‘African cherry’, is an evergreen tree, which grows up to 40 m in height, has open branches and a mature stem diameter of up to 1 m, and bears a blackish-brown stem-bark. Prunus africana is distributed in Central Africa, sub-Saharan Africa and the Indian Ocean islands. The stem-bark is...

Aloe ferox Mill. (Asphodelaceae), commonly known as ‘Cape aloe’, is indigenous to South Africa, occurring in the Free State, Eastern Cape and KwaZulu-Natal provinces. It is an arborescent perennial plant that reaches 2–3 m in height with leaves arranged in a rosette, characterised by bright red or yellow-orange flowers. Cape aloe is well known for...

Cyclopia genistoides (L.) R.Br (Fabaceae), commonly referred to as ‘honeybush tea’, is one of 23 Cyclopia species endemic to South Africa. The natural habitat of this small fynbos shrub is restricted to very small areas in the Western Cape Province, spanning from the West Coast to Mossel Bay on the Southern Cape coast. Honeybush tea is mostly enjoy...

Mesembryanthemum tortuosum L. (Aizoaceae) was previously classified as Sceletium tortuosum and is still widely referred to under that name in literature. Locally, the plant is known as ‘kanna’. The small scrambling succulent is endemic to South Africa and is found in the arid areas of the Western, Eastern and Northern Cape provinces. For centuries,...

Hypoxis hemerocallidea Fisch., C.A.Mey. & Avé-Lall. (Hypoxidaceae) is known as African potato. It is described as an herbaceous perennial plant, with a scythe-like appearance and bright yellow star-shaped flowers. It occurs in tropical and southern Africa, growing abundantly throughout the summer rainfall areas of South Africa. The rootstock is tra...

Helichrysum odoratissimum (L.) Sweet (Asteraceae), also known as ‘African incense’, ‘kooigoed’ and ‘imphepho’ is a perennial herb that reaches 1.75 m in height. The plant has a silver appearance and bears pale golden-yellow flowers. It is abundant throughout southern Africa, where it is one of the most popular traditional remedies. It occurs in six...

Helichrysum petiolare Hilliard & B.L.Burtt (Asteraceae), also known as ‘African incense’, ‘kooigoed’, and ‘imphepho’, is a perennial plant of 0.3–1 m in height, with round aromatic leaves that are tightly matted with hairs. The shrub occurs in the Western and Eastern Cape provinces of South Africa. The plant is burnt as incense to invoke the ancest...

Aspalathus linearis (Burm.f) R.Dahlgren, commonly referred to as ‘rooibos tea’, is the best-known indigenous South African herbal tea. It is considered the success story of indigenous product development and marketing, and it is a prime export product, marketed globally. Rooibos is endemic to the Fynbos Biome and is found in the far southwestern pa...

Prunus africana (Hook.f.) Kalkman (Rosaceae), commonly known as ‘African cherry’, is an evergreen tree, which grows up to 40 m in height, has open branches and a mature stem diameter of up to 1 m, and bears a blackish-brown stem-bark. Prunus africana is distributed in Central Africa, sub-Saharan Africa and the Indian Ocean islands. The stem-bark is...

Athrixia phylicoides DC. (Asteraceae), known as bush tea, is a leafy shrub that grows abundantly in South Africa and its neighbouring countries, including Lesotho and Swaziland. The plant is recognised as one of South Africa’s indigenous teas, since infusions of the aerial parts are enjoyed as a beverage. Several indigenous groups prepare decoction...

Xysmalobium undulatum (L.) Aiton (Apocynaceae), commonly referred to as ‘Uzara’, is a large perennial herb that grows up to 2 m in height and is widely distributed in the eastern parts of southern Africa. The plant bears creamy-green to yellow flowers, hairy fruits, and fleshy carrot-like roots, characterised by a nauseating smell. Xysmalobium undu...

Warburgia salutaris (G.Bertol.) Chiov. is a slender, aromatic, evergreen tree that belongs to the cinnamon family (Canellaceae). This species, found mainly in southern Africa, has the epithet ‘salutaris’ which means ‘salutary to health’ or ‘health-giving’, thus reflecting the initial use of the bark as a general tonic, while the common name, pepper...

Harpagophytum procumbens (Burch.) DC. ex Meisn. is an important traditional medicine that grows in the Kalahari region of southern Africa, where it is taken as a general health tonic and anti-inflammatory to treat arthritis, rheumatism, pain, sprains, fever, ulcers and boils. Iridoid glycosides and phenyl derivatives have been the focus of phytoche...

Agathosma betulina (P.J. Bergius) Pillans (Rutaceae), commonly referred to as ‘buchu’, is an evergreen, fragrant shrub that grows up to 2 m in height and is naturally distributed in the Western Cape Province of South Africa. The leaves are aromatic and, upon distillation, produce a golden oil, with a strong-sweetish, peppermint-like scent. Buchu oi...

Background Besides systemic drug delivery, the intranasal route of administration has shown potential for direct nose-to-brain drug delivery, which has gained popularity because it bypasses the blood-brain barrier. Objective The region in the nose from which the epithelial tissue membrane is excised to conduct ex vivo permeation studies for nasal...

Pelargonium sidoides DC. (Geraniaceae), also known as ‘African geranium’, is a small perennial, rosette-like plant with crowded leaves and distinctive dark, reddish-purple flowers. The roots of the plant have long been used in South African traditional medicine for the treatment of sore throat, congestion, bronchitis, diarrhoea and dysentery. Pelar...

Geraniol is an acyclic isoprenoid monoterpene that is biosynthesised by a large number of aromatic plants. It is widely used in cosmetics, household products and pharmaceuticals, because of its low toxicity and environmentally-friendly profile. An increasing demand for the compound has encouraged research into alternative synthetic routes, and grea...

Salvia africana-lutea L., S. lanceolata L., and S. chamelaeagnea L. are used in South Africa as traditional medicines to treat infections. This paper describes an in-depth investigation into their antibacterial activities to identify bioactive compounds. Methanol extracts from 81 samples were screened against seven bacterial pathogens, using the mi...

Devil's claw is a popular natural anti-inflammatory phytomedicine. The preparation of Devil's claw products is complicated by the similarity between the morphotypes of Harpagophytum procumbens and H. zeyheri. This study investigated the potential of a validated ultra-high performance liquid chromatography coupled to mass spectrometry (UHPLC-MS) met...

Ethnopharmacological relevance Mesembryanthemum tortuosum L. (previously known as Sceletium tortuosum (L.) N.E. Br.) is indigenous to South Africa and traditionally used to alleviate anxiety, stress and depression. Mesembrine and its alkaloid analogues such as mesembrenone, mesembrenol and mesembranol have been identified as the key compounds respo...

Agathosma betulina (P.J.Bergius) Pillans (Rutaceae), commonly known as ‘buchu’, is an evergreen, aromatic shrub that is naturally distributed in the Western Cape Province of South Africa. The plant has an extensive history of traditional use by indigenous South African cultures, where leaf infusions and tinctures are used medicinally for the treatm...

Harpagophytum procumbens (Burch.) DC. ex Meisn. (Pedaliaceae), commonly known as ‘devil’s claw’, is a weedy, tuberous plant with creeping stems that grow up to 2 m in height. The plant is found in Namibia, Botswana, South Africa and Angola. The major traditional uses include treatment of arthritis, blood diseases and urinary tract infections. The p...

Terminalia sericea Burch ex DC. is a small to medium-sized tree of about 5–8 m, although some trees can reach up to 23 m in height. Silvery hairs adorn the leaves, while the bark is grey to brown and coarsely fissured. The tree is widely distributed throughout Africa, particularly in savannah woodland environments. In South Africa, it is abundant i...

This iconic succulent, indigenous to South Africa, probably boasts the longest recorded history of medicinal plant use in the country and was the first phytomedicine to be exported from South Africa dating back to the 1600s. Aloe ferox Mill. is widely distributed in South Africa where it is traditionally used topically to treat various skin conditi...

Bulbine frutescens (L.) Willd. is a succulent plant, with thornless yellowish-green leaves. The stems are branched at the base and the yellow flowers are borne in elongated clusters on thin flowering stems. The stamens are hairy, a very distinctive character for these species. This robust succulent is widely distributed throughout several provinces...

Adansonia digitata L. (Malvaceae), commonly known as ‘baobab’, is a large tree used in Africa for its medicinal and nutritional value. In many African countries, different plant parts are used to treat malaria, diarrhoea, fever, inflammation, kidney and bladder diseases. Baobab is a rich source of vitamin C, yielding levels of ascorbic acid rivalli...

Eriocephalus punctulatus DC. (Asteraceae), commonly known as ‘Cape chamomile’, is a small bushy shrub that can reach up to 1 m in height. The needle-like leaves are long, narrow and gland-dotted. The plant, endemic to South Africa, occurs in the Western Cape and Northern Cape provinces. Cape chamomile essential oil is commercially important and has...

Helichrysum odoratissimum (L.) Sweet (Asteraceae), commonly known as ‘African incense’, is an aromatic shrub, which occurs in many southern African countries, including Swaziland, Lesotho, Mozambique, Zambia, Zimbabwe and South Africa. The plant has a long history of traditional use for the treatment of heart disease, hypertension, diabetes, menstr...

Leonotis leonurus (L.) R.Br. (Lamiaceae) is a woody bush with greyish, velvety square stems in young plants. It is commonly known as ‘wild dagga’. The plant is widely distributed in South Africa, Mozambique and Zimbabwe. Leonotis leonurus is traditionally used for the treatment of different skin disorders, respiratory and menstrual complaints, high...

Prunus africana (Hook.f.) Kalkman (Rosaceae), commonly known as ‘African cherry’, is a large tree that can reach up to 20 m in height. The leaves impart a characteristic almond smell when bruised. The tree bears creamy-white flowers and purplish-red cherries that turn black when ripe. Prunus africana is widespread in many African countries includin...

Sclerocarya birrea (A.Rich.) Hochst. (Anacardiaceae), commonly referred to as ‘marula’, is one of the most highly valued indigenous trees in South Africa. The tree is tall, reaching up to 15 m, with a grey bark and greenish leaves that have smooth margins. Marula trees occur in warm climates throughout Africa, from northern Ethiopia to the KwaZulu-...

Pelargonium sidoides DC. is indigenous to South Africa, with the centre of diversity in the Eastern Cape Province. The plant has crowded velvety, cordate, long stalked leaves with short glandular hairs. The flowers are very dark reddish-purple to almost black. Various ethnic groups have used root extracts of P. sidoides as a remedy for coughs, uppe...

The highly aromatic Lippia javanica (Burm.f.) Spreng (Verbenaceae) is a multipurpose medicinal shrub with leaves that have a characteristic lemon-scent when bruised. ‘Fever-bush’ as it is commonly known, has widespread ethnobotanical applications, including the treatment of fevers, respiratory and gastrointestinal complaints, skin infections and in...

Lessertia frutescens (L.) Goldblatt & J.C. Manning (Fabaceae), a small shrub that grows naturally in some southern African countries, has reputable medicinal properties in the management of a vast range of ailments. ‘Cancer bush’, as the plant is commonly referred to, is used in the treatment of cancers, as a bitter tonic, adaptogen and blood purif...

Warburgia salutaris (G. Bertol.f.) Chiov. (Canellaceae) is an endangered, medicinal tree distributed in a few locations in South Africa, Swaziland, Zimbabwe, Mozambique, Malawi and Zambia. The bitter, peppery-taste of the stem bark has earned W. salutaris the name ‘pepper bark tree’. Ethnomedicinally, the important part of the tree is the bark, whi...

Cyclopia genistoides (L.) R.Br. (Fabaceae), commonly known as ‘honeybush’, is a commercially important species of the genus Cyclopia. The small woody shrub is multi-branched with small narrow leaflets and bright yellow, pea-shaped flowers. The species is endemic to the Fynbos Biome of South Africa, where it grows in the coastal districts and mounta...

Hoodia gordonii (Masson) Sweet ex Decne. (Apocynaceae), commonly known as ‘bitterghaap’, is a leafless succulent plant that is distributed in some southern African countries including Namibia, Botswana, Angola and South Africa. Traditionally, the plant is commonly used as an appetite and thirst suppressant and for the treatment of tuberculosis, can...

Pelargonium graveolens L’Hér. (Geraniaceae), also known as ‘rose-scented geranium’, is a shrub with hairy stems and velvety leaves that grows to a height of 1.3 m. The plant occurs in South Africa, Zimbabwe and Mozambique. The plant is well-known for its essential oil (geranium oil), which is used in the fragrance, flavour and aromatherapy industri...

Hypoxis hemerocallidea Fisch., C.A.Mey. & Avé-Lall (Hypoxidaceae), a short tuberous plant with bright yellow, star-shaped flowers, is hailed for the ethnomedicinal properties of the corms. The ‘African potato’ as the plant is commonly known, is used as an immune booster, tonic for HIV patients and for the treatment of respiratory, skin and stomach...

Athrixia phylicoides DC. is an aromatic shrub belonging to the Asteraceae family. The species is mostly referred to as ‘bush tea’ and used throughout South Africa, where it grows abundantly in several provinces. The leaf infusions are taken as beverages and used to treat hypertension, heart disease, headache, infested wounds and skin conditions. A...

Xysmalobium undulatum (L.) Aiton commonly known as ‘uzara’, is widely distributed in many countries in southern Africa. This robust annual herb can grow up to 1 m high from a perennial rootstock, and has thick and erect hairy branches. The plant has a strong flowering stem arising from a branched fleshy root. The leaves are arranged in opposite pai...

Aspalathus linearis (Brum.f) R.Dahlgren (Fabaceae), commonly referred to as ‘rooibos tea’, is native to South Africa and restricted to a relatively small region in the Western Cape Province. Rooibos tea is mostly enjoyed as a beverage and also used medicinally to improve appetite, reduce nervous tension and alleviate indigestion, heartburn, nausea...

Artemisia afra Jacq. ex Willd. (Asteraceae), also known as ‘African wormwood’, is a multi-stemmed and aromatic shrub with a height of approximately 2 m. The plant has a wide distribution range in South Africa. The roots, stems and leaves of A. afra are used in various forms, such as infusions, body washes, lotions, smoke and snuff, to treat colic,...

Helichrysum petiolare Hilliard & B.L.Burtt (Asteraceae) is an aromatic and low-growing shrub. The plant is also commonly known as ‘herbal helichrysum’. It grows mainly in the Eastern and Western Cape provinces of South Africa. Helichrysum petiolare is traditionally used in the treatment of fungal infections, menstrual disorders, urinary tract infec...

Mesembryanthemum tortuosum L. is endemic to the karroid areas of the Western and Northern Cape provinces of South Africa. It is a decumbent or a scrambling perennial sub-shrub, bearing flowers that are more or less sessile and 2–3 cm in diameter, with colours ranging from white to pale yellow, pale salmon or pale pink. The plant has a rich ethnobot...

Ethnopharmacological relevance Epilepsy is one of the major chronic diseases that does not have a cure to date. Adverse drug reactions have been reported from the use of available antiepileptic drugs (AEDs) which are also effective in only two-thirds of the patients. Accordingly, the identification of scaffolds with promising anti-seizure activity...

The South African Salvia species, Salvia africana-lutea, S. lanceolata and S. chamelaeagnea, are widely used to treat fever and inflammation associated with skin and lung infections. The aim of this study was to explore the non-volatile secondary metabolites and the phytochemical variation within these lesser known species, to support product devel...

Helichrysum petiolare and Helichrysum odoratissimum, collectively known as ‘Imphepho’, are popular medicinal herbs that are indigenous to South Africa. The species are used interchangeably to relieve gastrointestinal and respiratory conditions, fever and urinary tract infections, implying that they produce antibacterial compounds. Although these he...

Terminalia sericea is used throughout Africa for the treatment of a variety of conditions and has been identified as a potential commercial plant. The study was aimed at establishing a high-performance thin layer chromatography (HPTLC) chemical fingerprint for T. sericea root bark as a reference for quality control and exploring chemical variation...

Tyrosinase is the key enzyme in the production of melanin. Tyrosinase inhibitors have gained interest in the cosmetics industry to prevent hyperpigmentation and skin-related disorders by inhibiting melanin production. It has been reported that several Aloe species exhibit anti-tyrosinase efficacy in vitro. In this study, the exudates of thirty-nine...

Ethnopharmacological relevance Many species within the family Combretaceae are popular medicinal plants that are used traditionally to treat various conditions, of which many are related to bacterial infections. Global concerns regarding the increasing resistance of pathogens towards currently available antibiotics have encouraged researchers to fi...

Artemisia afra, (African wormwood) is a popular medicinal plant of southern Africa and is an excellent candidate for commercialisation. This current study was aimed at exploring the phytochemistry and chemical variation of non-volatile compounds within wild populations of A, afra, and developing chromatographic quality control protocols for raw mat...

Inhibition of acetylcholinesterase (AChE) is considered a promising strategy for the treatment of Alzheimer's disease (AD) and dementia. Members of the Amaryllidaceae family are well known for their pharmacologically active alkaloids, including galanthamine, which is used to treat AD. The aim of this study was to evaluate the potential of South Afr...

Piper methysticum Forst., commonly referred to as kava, has been used medicinally and recreationally by inhabitants of the South Pacific Islands for centuries. Kavalactones present in roots and aerial parts are regarded as the bioactive compounds responsible for the relaxant effects, and for mitigating anxiety and stress-related conditions. The dev...

Quorum sensing controls bacterial pathogenesis and virulence; hence, interrupting this system renders pathogenic bacteria non-virulent, and presents a novel treatment for various bacterial infections. In the search for novel anti-quorum sensing (AQS) compounds, 14 common culinary herbs and spices were screened for potential antipathogenicity activi...

The aim of this study was to investigate the antimicrobial activity of endophytes isolated from the root of Pelargonium sidoides DC., and to explore the antimicrobial interactions between endophytic fungi and the host plant. The hypothesis explored is that medicinal plants used as an anti-infective may not only rely on the properties of the medicin...

Sutherlandia frutescens, commonly known as cancer bush, is a popular herbal remedy which has been used traditionally for the treatment of internal cancers, stress, influenza, fever, diabetes, stomach ailments and as a tonic. SU1 (syn = sutherlandioside B) is a major cycloartane-type triterpene glycoside in the leaf material and it has been used as...

Sceletium tortuosum (Aizoaceae) is widely recognised for the treatment of stress, anxiety and depression, as well as for obsessive compulsive disorders. A comprehensive intraspecies chemotypic variation study, using samples harvested from two distinct regions of South Africa, was done using both proton nuclear magnetic resonance (1H-NMR) spectrosco...

Athrixia phylicoides, known as “bush tea”, grows abundantly in South Africa. An infusion of the leaves is used as a beverage and to treat a multitude of health conditions. The aim of this study was to investigate the chemical variation within A. phylicoides and to identify characteristic compounds for quality control. Samples from 12 locations in S...

The consumption of herbal teas is increasing as consumers become more appreciative of the health benefits. Herbal tea blends comprise of two or more plant species blended to improve taste and multiply the health benefits. Quality control (QC) of herbal teas like other nutraceuticals, is important to ensure safety and efficacy. Current QC methods ar...

The African wild olive (Olea europaea subsp. africana) is traditionally used as a hypotensive agent. Herb-drug interactions may result from the concurrent use of herbal medicines and conventional prescription drugs. This aspect was investigated by determining the effect of the extract on the in vitro intestinal epithelial permeation of selected hyp...

Chemical interrogation of the Sceletium genus and Amaryllidaceae family of plants has yielded a diverse array of aryl-hydroindole containing alkaloids. Included in this class is channaine, which was tentatively identified, without comprehensive structural elucidation from Sceletium tortuosum in 1957. Following its isolation from S. strictum, the st...

Actaea racemosa (black cohosh) has a history of traditional use in the treatment of general gynecological problems. However, the plant is known to be vulnerable to adulteration with other cohosh species. This study evaluated the use of shortwave infrared hyperspectral imaging (SWIR-HSI) in tandem with chemometric data analysis as a fast alternative...

In South Africa, indigenous herbal teas are enjoyed due to their distinct taste and aroma. The acclaimed health benefits of herbal teas include the management of chronic diseases such as hypertension and diabetes. Quality control of herbal teas has become important due to the availability of different brands of varying quality and the production of...

Henna (Lawsonia inermis) is applied to stain keratin, present in hair, skin and fingernails, a red-orange or rust colour. Producers of temporary tattoos mix the aromatic amine compound, para-phenylenediamine (PPD) into natural henna to create ‘black henna’ that rapidly stains the skin black. However, PPD may cause severe delayed hypersensitivity re...

The name “ginseng” is collectively used to describe several plant species, including Panax ginseng (Asian/Oriental ginseng), P. quinquefolius (American ginseng), P. pseudoginseng (Pseudoginseng) and Eleutherococcus senticosus (Siberian ginseng), each with different applications in traditional medicine practices. The use of a generic name may lead t...

Stephania tetrandra ("hang fang ji") and Aristolochia fangchi ("guang fang ji") are two different plant species used in Traditional Chinese Medicine (TCM). Both are commonly referred to as "fang ji" and S. tetrandra is mistakenly substituted and adulterated with the nephrotoxic A. fangchi as they have several morphological similarities. A. fangchi...

Context: Xysmalobium undulatum (L.) Aiton f var. (Asclepiadaceae), commonly known as uzara, is an ethnomedicinally important plant from southern Africa used to treat a variety of ailments. In addition to local use in African Traditional Medicine (ATM), formulations containing uzara have been successfully marketed by a number of pharmaceutical comp...

The leaves of Catha edulis Vahl. Endl., known as Khat, are widely used as a "natural amphetamine" stimulant in Africa and in the Arabian Peninsula. In recent years, there has been an increase in the amounts exported to the USA, Australia and Europe. Although the dried, powdered form of the young and mature leaves, as well as samples from different...

Aloe ferox is an important medicinal plant indigenous to South Africa where it has primarily been used as a purgative and also to treat skin disorders. Modern day uses include; health (tonic) drinks, flavourant in alcoholic beverages, treatment of digestive disorders and inclusion in cosmetic formulations. Due to increased commercialization of aloe...

Harpagophytum procumbens (Pedaliaceae) and its close taxonomical ally Harpagophytum zeyheri, indigenous to southern Africa, are being harvested for exportation to Europe where phytomedicines are developed to treat inflammation-related disorders. The phytochemical variation within and between natural populations of H. procumbens (n = 241) and H. zey...

Scutellaria lateriflora (skullcap) is a medicinal herb that has a long history of use in the treatment of ailments such as insomnia and anxiety. Commercial herbal formulations claiming to contain S. laterifolia herba have flooded the consumer markets. However, due to intentional or unintentional adulteration, cases of hepatotoxicity have been repor...

The well-known anti-infective properties of propolis are determined by its chemical composition, which in turn is influenced by geographical factors and reflects the botanical diversity in the vicinity of the beehive. Although there are several reports on the anti-infective properties of crude propolis, few are aimed at identifying specific compoun...

Echinacea species are popularly included in various formulations to treat upper respiratory tract infections. These products are of commercial importance, with a collective sales figure of $132 million in 2009. Due to their close taxonomic alliance it is difficult to distinguish between the three Echinacea species and incidences of incorrectly labe...

Aims: This study reports on the inhibitory and bactericidal properties of 39 South African (SA) propolis samples and three propolis samples from Brazil. Methods and Results: Ethanolic extracts of propolis (EEP) were prepared and their antimicrobial activities tested using the minimum inhibitory concentration (MIC) and minimum bactericidal concentra...

Harpagophytum procumbens (Burch.) DC. ex Meisn. subsp. procumbens (Pedaliaceae) has a long history of ethnobotanical use. The plant grows in the Kalahari region of southern Africa where it is consumed to treat inflammation-related disorders. Together with H. zeyheri, it is known as 'Devil's Claw'. The two taxa are botanically and chemically similar...

Two Pelargonium species which are indigenous to South Africa; P. sidoides DC and P. reniforme Curt., are highly valued traditional remedies used primarily for the treatment of upper respiratory tract infections. The ethnobotanical value of P. sidoides has led to the commercialisation of herbal medicinal products such as Umckaloabo® that are markete...

The enormity of the herbal medicines industry is emphasised by the fact that 80% of the world's population use herbal medicines. However, due to country-specific legislation (or lack thereof) herbal medicines are often not closely regulated and quality and safety cannot be guaranteed. Herbal medicines are notoriously phytochemically complex mixture...

The fragrant camphor tree (Cinnamomum camphora) and its products, such as camphor oil, have been coveted since ancient times. Having a rich history of traditional use, it was particularly used as a fumigant during the era of the Black Death and considered as a valuable ingredient in both perfume and embalming fluid. Camphor has been widely used as...

Harpagophytum procumbens and H. zeyheri (Pedaliaceae) are widely distributed in southern Africa. They are highly valued traditional medicines used in the treatment of inflammation and pain-related ailments such as rheumatoid arthritis, ulcers and boils [1]. The biological activity of the species has been ascribed to the presence of iridoid glycosid...

Harpagophytum procumbens subps. procumbens (Burch.) DC. ex Meisn. (Pedaliaceae) is an important traditional medicine growing in the Kalahari region of southern Africa where it is consumed as a general health tonic and for treating diverse ailments including arthritis, pain, fever, ulcers and boils. To provide a comprehensive overview of the ethnobo...

Anecdotal evidence indicates that Sceletium tortuosum has been used as a psychoactive preparation for several centuries. The psychological activity is attributed to the production of mesembrine-type alkaloids (mesembrenol, mesembranol, mesembrenone and mesembrine) by the plant. This investigation was aimed at developing validated reversed phase ult...

The genus Salvia (Lamiaceae) encompasses about 900 species worldwide of which 26 are found in southern Africa. Salvia spp have several medicinal uses in South Africa such as antimicrobial, anti-cancer, antimalarial, and antituberculosis properties. Rosmarinic acid (RA) has been identified as one of the major molecules respon-sible for these various...