I Vermaak

Publications (4)2.17 Total impact

• Source

  Available from: Guy Paulin Poungoue Kamatou

  Dataset: An updated review of Adansonia digitata: A commercially important African tree

  G P P Kamatou, I Vermaak, A M Viljoen
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  ABSTRACT: Adansonia digitata L. (Malvaceae) is a majestic tree revered in Africa for its medicinal and nutritional value. The plant parts are used to treat various ailments such as diarrhoea, malaria and microbial infections. It is reported that it is an excellent anti-oxidant due to the vitamin C content which is seven to ten times higher than the vitamin C content of oranges. Baobab has numerous biological properties including antimicrobial, anti-viral, anti-oxidant and anti-inflammatory activities amongst others. Phytochemical investigation revealed the presence of flavonoids, phytosterols, amino acids, fatty acids, vitamins and minerals. The seeds are a source of significant quantities of lysine, thiamine, calcium and iron. Baobab is an important commodity which is integral to the livelihood of rural communities. In addition, the global demand for baobab raw material (e.g. seed oil, fruit pulp) by the food and beverage, nutraceutical and cosmetic industries has increased dramatically in recent years thereby increasing the commercial value and importance of this coveted African tree. In the past few years, there has been an increased demand for non-timber forest products (NTFPs), specifically baobab seed oil for inclusion in cosmetic formulations due to its high fatty acid composition. This review summa-rises the botanical aspects, ethnobotany, phytochemistry, biological properties and most importantly the nutritional value and commercial impor-tance of baobab products.
• Source

  Available from: Guy Paulin Poungoue Kamatou

  Dataset: African seed oils of commercial importance — Cosmetic applications

  I Vermaak, G P P Kamatou, B Komane-Mofokeng, A M Viljoen, K Beckett
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  ABSTRACT: Seed oils have been used for centuries by rural communities as food, medicine, for cosmetic applications and as fuel. Recently there has been a renewed interest in these non-timber forest products (NTFPs) specifically for use in cosmetic formulations. The cosmetic industry remains under immense consumer pressure to produce innovative products for this lucrative industry. Like the pharmaceutical industry, the wellness industry turns to nature for guidance, inspiration and as a source of novel compounds to produce new consumer products. Furthermore, discerning consumers of cosmetic products are nowadays informing themselves of the validity of scientific claims made on various products. The seed oils extracted from several plant species are popularly included as ingredients in cosmetic products due to their high fatty acid composition. The information on African seed oils is scattered in literature and often published in obscure and dated manuscripts. With an emphasis on (but not restricted to) cosmetic applications the botanical aspects, uses, physico-chemical properties and oil composition as well as biological activity of six commercially important species are coherently united and reviewed in this paper and include; Adansonia digitata (baobab), Citrullus lanatus (Kalahari melon), Schinziophyton rautanenii (manketti/mungongo), Sclerocarya birrea (marula), Trichilia emetica (mafura butter) and Ximenia americana (sour plum).
• Source

  Available from: def-sa.com

  Article: In vitro transport of the steroidal glycoside P57 from Hoodia gordonii across excised porcine intestinal and buccal tissue.

  I Vermaak, A M Viljoen, W Chen, J H Hamman
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  ABSTRACT: Hoodia gordonii was traditionally used by the Khoisan people as a thirst and appetite suppressant and is currently commercially available as a popular weight-loss supplement. The perceived active ingredient isolated from this plant is a steroidal glycoside named P57. This study aimed at investigating the in vitro transport of P57 across excised porcine intestinal and buccal mucosa in a Sweetana-Grass diffusion apparatus. For both the intestinal and buccal experiments, the transport of pure P57 was compared to that obtained from a crude plant extract. Bi-directional transport experiments were conducted across the intestinal tissue in two different media namely Krebs-Ringer bicarbonate buffer and simulated intestinal fluid. Apical-to-basolateral transport experiments were conducted across the buccal tissue in two different media namely Krebs-Ringer bicarbonate buffer and artificial saliva. Apparent permeability coefficient (P(app)) and flux values were calculated and analysed by means of a one-way repeated analysis of variance (ANOVA) to determine if differences were significant (p≤0.05). The transport of pure P57 across intestinal tissue was significantly higher in the secretory direction than in the absorptive direction indicating efflux by membrane transporters. Much higher intestinal transport was obtained for P57 in both directions when applied in the form of a crude extract, possibly due to inhibition of efflux as indicated by lower secretory transport compared to absorptive transport. For the buccal tissue, no transport was obtained for the pure P57, while relatively high transport was obtained when applied in the form of a crude extract. Furthermore, the intestinal transport of P57 was significantly decreased when the crude extract was prepared in simulated intestinal fluid compared to when it was prepared in buffer. On the other hand, buccal transport was higher in artificial saliva than in buffer. It is therefore evident that the transport of P57 across mucosal tissues is significantly affected on exposure to conditions simulating the in vivo situation.
  Phytomedicine: international journal of phytotherapy and phytopharmacology 02/2011; 18(8-9):783-7. · 2.17 Impact Factor
• Article: The effect of simulated gastrointestinal conditions on the antimicrobial activity and chemical composition of indigenous South African plant extracts

  I. Vermaak, A.M. Viljoen, J.H. Hamman, S.F. Van Vuuren
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  ABSTRACT: Few in vitro screening assays for biological activities of plant extracts consider the potential effect of the gastrointestinal system on orally consumed plant extracts. Crude water and methanol extracts of Tarchonanthus camphoratus (wild camphor) and Agathosma betulina (‘buchu’) were prepared and exposed to simulated gastric fluid and simulated intestinal fluid during dissolution studies to address this aspect. The crude extracts and resulting simulated gastric fluid and simulated intestinal fluid products were screened for antimicrobial activity against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212), Escherichia coli (ATCC 25922) and Proteus vulgaris (ATCC 33420). The T. camphoratus crude extract exhibited antimicrobial activity which was reduced after exposure to simulated gastric fluid. After exposure to simulated intestinal fluid no antimicrobial activity was detected, which suggests chemical alteration or degradation of the active compounds. For A. betulina, the crude water extract and simulated gastric fluid product exhibited no antimicrobial activity, while the simulated intestinal fluid product exhibited antimicrobial activity. This suggests activation of antimicrobial constituents during exposure to simulated intestinal fluid. The chemical composition profiles of the crude extracts and products were determined by means of liquid chromatography coupled to an ultraviolet detector (LC-UV) and a mass spectrometer (LC-MS) to qualitatively assess the effect of exposure to simulated gastrointestinal conditions on the chemical composition of the extracts. In many cases, the peak area of compounds decreased after exposure to simulated gastric fluid and simulated intestinal fluid, while the peak area of other compounds increased. Thus, it can be deduced that the antimicrobial activity and chemical composition was altered after exposure to intestinal conditions during dissolution studies.
  South African Journal of Botany.