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The resin of the plant Commiphora wildii Merxm. (omumbiri) is traditionally used by Ovahimba women (Kunene, Namibia) as the main ingredient for their perfume. Although essential oil produced from the resin by steam distillation is sold commercially, its detailed chemical composition and biological properties are not known. Knowledge on the potential antimicrobial and antioxidant activities of C. wildii essential oil is desired by perfume, cosmetics, and detergent manufacturers, in order to add value to their products when using the oil as an ingredient. Furthermore, once the oil has been chemically characterized, the concentrations of the bioactive constituents can be monitored for quality‐control purposes. In this study the chemical characterization of the volatile constituents of the essential oil of C. wildii resin was performed using gas chromatography–mass spectrometry (GC–MS) and GC coupled to a flame ionization detector (GC–FID). Fifty compounds were identified in the oil, most of which were terpenoids. The major compounds were α‐pinene (50.0% w/w), heptane (24.0% w/w), and β‐pinene (11.7% w/w). The antimicrobial activity of the oil was determined against Candida albicans, Escherichia coli, Klebsiella pneumaniaea, and Staphylococcus aureus. The best antimicrobial activity was noted against S. aureus, with a minimum inhibitory concentration (MIC) of 8 mg ml–1. Biofilm reduction was below 40%, but inhibition was between 93% (K. pneumaniaea) and 99% (C. albicans). An 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging assay revealed the antioxidant potential of the oil (with a half‐maximal inhibitory concentration, IC50, of 0.2257 mg ml–1).These results may be used by different industries to guide the formulation of their products and also to assess the safety of this oil when used as an ingredient.

Gampocarpus fruticosus is a wild plant that belongs to the Asclepiadaceae family and has many traditional uses. The plant has demonstrated a significant level of microbial and phytochemical activity; the drugresistant strains of microbes and traditional uses which have emerged in the last decade will be eradicated by the compounds this indigenous plant carries. Phytochemical screening was executed followed by the evaluation of total flavonoid, phenol and tannin content using aluminium chloride method, folin-ciocalteu method and the potassium ferrocyanide methods respectively. Antimicrobial screening as well as MIC determination was done using the disk diffusion method. The antioxidant activity was determined using the DPPH Free Radical Scavenging Method. The quantitative phytochemical determinations were performed in triplicate and expressed as means (± standard deviation) and of the phytochemicals that were quantified, tannins were present in large amounts with 6.937±0.115 mg TA/g in the methanolic extract and 5.356±0.185 mg TA/g in the ethanolic extract. The MIC values for antimicrobial analysis were recorded as the minimum application of plant extracts that totally repressed the growth of the microorganism. The MIC value for the ethanolic extract on Staphylococcus aureus was 1 mg/ml and for Escherichia coli it was 6 mg/ml. For DPPH, the extract with the lowest IC₅₀ was the one with the highest scavenging activity. The standard used was Vitamin C and it had an IC₅₀ value of 0.37 mg/ml. The IC₅₀ value of the methanolic extract and ethanolic extract were 0.25 mg/ml and 0.34 mg/mlrespectively. The main highlights of this article are their greater medicinal value of phytochemicals present, antimicrobialactivity and antioxidant activity that was exhibited by the leaf extract of G.fruticosus plant.

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The current situation in many developing countries is that, vegetable oils are replacing animal fats because of health concerns and cost. The objective of the study was to compare the iodine value, acid value, ester value, peroxide value, saponification number and cholesterol content of some locally produced vegetable oils like refined marula cooking oil, marula traditional cooking oil, marula cosmetic oil, melon oil, ximenia oil viz. olive oil and commercial sunflower oil. The physicochemical analysis helps to justify the usage of these different traditional oils. The analysis showed that marula cooking oil is close to olive oil in the unsaturation level and better than olive oil in ester value, peroxide value and has lower cholesterol content.