Abstract Lippia javanica and Lippia scaberrima are used as herbal remedies and are commercially traded as health teas in southern Africa under the brands “Mosukujane” and “Musukudu”, respectively. This study evaluates the relationship between the presence of phenolic compounds and the antioxidant activities of infusions prepared from four Lippia species (L. javanica, L. scaberrima, L. rehmannii and L. wilmsii) indigenous to South Africa. The antioxidant activities of the infusions, determined by the 2,2-diphenylpycrylhydrazyl (DPPH) method, were also compared to those of popular black, green and herbal tea brands. Of the four indigenous species, infusions of L. javanica and L. wilmsii exhibited the highest antioxidant activities (EC50: 358 and 525 μg/ml, respectively) and contained the most phenolic compounds (14.8 and 14.5 mg/ml of dry weight gallic acid equivalent, respectively). Antibacterial activities of methanolic extracts of the four Lippia species were determined against four human pathogens (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and Pseudomonas aeruginosa). The extract of L. javanica was the most active against all the pathogens tested. Those Lippia species (L. javanica and L. wilmsii) previously reported to produce higher levels of the pharmacologically active phenylethanoid glycosides verbascoside and isoverbascoside, portrayed stronger antioxidant and antibacterial activities. This study gives credence to the use of infusions of these Lippia species for their general health benefits.

Abstract The purpose of this study was to determine the impact of resistance training, designed to prevent the development of coronary heart disease (CHD) based on the Framingham Risk Assessment (FRA) score. Twenty-five healthy sedentary men with low CHD risk were assigned to participate in a 16-week (three days per week) resistance training programme (n = 13) or non-exercising control group (CG) (n = 12). Resistance training was performed using eight whole-body exercises for three sets of 15 repetitions at 60% of one-repetition maximum. Resistance training did not significantly (p > 0.05) reduce the number of cigarettes smoked daily (p > 0.133) or TC (p > 0.917), while significant improvements were found in SBP (p < 0.003), HDLC (p < 0.005) and FRA score (p < 0.021); thus improving absolute 10-year risks for CHD. The CG subjects were found to have had no significant changes in number of cigarettes smoked daily (p > 0.831), TC (p > 0.678), HDLC (p > 0.672) or FRA score (p > 0.504), but SBP increased significantly (p < 0.030). These data indicate that resistance training can effectively reduce the predicted risk of developing CHD, even in men with already low risk.

A bstract Few in vitro screening studies on the biological activities of plant extracts that are intended for oral administration consider the effect of the gastrointestinal system. This study investigated this aspect on extracts of Camellia sinensis (green tea) and Salvia officinalis (sage) using antimicrobial activity as amodel for demonstration. Both the crude extracts and their products after exposure to simulated gastric fluid (SGF) as well as simulated intestinal fluid (SIF) were screened for antimicrobial activity. The chromatographic profiles of the crude plant extracts and their SGF as well as SIF products were recorded and compared qualitatively by means of high performance liquid chromatography coupled to mass spectrometry. The effect of epithelial transport on the crude plant extracts was determined by applying them to an in vitro intestinal epithelial model (Caco-2). The crude extracts for both plants exhibited reduced antimicrobial activity after exposure to SGF, while no antimicrobial activity was detected after exposure to SIF. These results suggested chemical modification or degradation of the antimicrobial compounds when exposed to gastrointestinal conditions. This was confirmed by a reduction of the peak areas on the LC–UV–MS chromatograms. From the chromatographic profiles obtained during the transport study, it is evident that some compounds in the crude plant extracts were either not transported across the cell monolayer or they were metabolised during passage through the cells. It can be deduced that the gastrointestinal environment and epithelial transport process can dramatically affect the chromatographic profiles and biological activity of orally ingested natural products.

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.

Abstract Despite the clear benefits that resistance training might have in weight management the effects of resistance training on adiposity in sedentary individuals are unsubstantiated. As such, the aim of the study was to determine the effect of resistance training on anthropometric measures of total, central and abdominal adiposity. Twenty-five healthy, sedentary males not on an energy-restricted diet were assigned to a non-exercising control group (CON) (n = 12) or a resistance training group (RES) (n = 13) to determine the effect of 16 weeks of resistance training on anthropometric measures of total, centrally located and abdominal adiposity. Resistance training was prescribed three times weekly using eight exercises for three sets of 15 repetitions at 60% of one-repetition maximum. Resistance training decreased three of the six anthropometric measures of total adiposity and increased body mass and body mass index (BMI). Resistance training had no impact on the measures of centrally located and abdominal adiposity. Body mass and BMI should be used with caution in risk calculations and measures of total adiposity in individuals engaging in resistance training due to this mode of training increasing lean mass (and thus body mass and BMI). Resistance training reduced total adiposity but did not provide an effective stimulus to lower centrally located and abdominal adiposity.

Extracts of seventeen Salvia species used in traditional medicine in South Africa were subjected to biological testing. The potential ability to inhibit the in vitro growth/proliferation of Plasmodium falciparum (FCR-3 strain) and the cytotoxic effects on three human cancer cells [breast adenocarcinoma (MCF-7), colon adenocarcinoma (HT-29) and glioblastoma (SF-268)] and a human kidney epithelial cell line were investigated. The extracts displayed antimalarial activity with IC50 values ranging from 3.91 to 26.01 μg/ml and S. radula displaying the most favorable activity. Two compounds were subsequently isolated from the active fraction of S. radula and identified as betulafolientriol oxide and salvigenin. The two compounds displayed similar or lower antimalarial activity (IC50 values: 4.95 and 24.60 μg/ml, respectively) compared to the crude solvent extract. The concentration required to inhibit 50% of cancer cells ranged between 9.69 μg/ml and 43.65 μg/ml, and between 8.72 μg/ml and 59.12 μg/ml against the MCF-7 and SF-268 cell lines, respectively. The IC50 values determined for the HT-29 cell line ranged from 17.05 to 57.00 μg/ml, with S. lanceolata being the most active. The samples also displayed some degree of toxicity when tested against the human kidney epithelial cells, with IC50 values ranging from 12.12 to 53.34 μg/ml. The in vitro antimalarial and anticancer activities support the historic and present use of Salvia species in traditional medicine.

Aims of the study: In South Africa, the genus Helichrysum is widely used in traditional medicine. The uses are well documented although renaming of species and the resulting confusing taxonomic nomenclature may cause uncertainty as to which specific species was referred to in some reports. The aim of this paper is to present a collated and coherent overview of the documented traditional uses of Helichrysum species and to update the botanical identity of previously studied species. Materials and methods: Databases (Scifinder, ISIWeb of Knowledge) and several bookswere used to collect in information on South African Helichrysum species. Results: The traditional uses, chemistry and biological activity of Helichrysum species have been summarized. It was attempted to give clarity as to exactly which species is refer to in the ethnobotanical literature. Conclusions: Although a largenumber of ethnopharmacological uses have beendocumentedand the chemistry of the genus has been studied extensively, only a few South African species have been investigated for their biological activity.

Heteropyxis natalensis (Heteropyxidaceae) is traditionally used to treat respiratory disorders, and as a decongestant and antimicrobial agent. The seasonal variation of the hydrodistilled essential oil was investigated. Three trees in the Johannesburg Botanical Garden (Gauteng) indicated similar chemical profiles with fluctuation in the levels of the two major constituents (1,8-cineole and limonene). Little variation between the antimicrobial activity of seasonally collected samples was documented, with standard deviations of ±0.3 to ±3.3 depending on the pathogen studied. Moderate antimicrobial activity (3.0–16.0 mg/ml) was noted for most pathogens tested with Cryptococcus neoformans exhibiting the highest sensitivity (2.0–3.0 mg/ml). The chemogeographical variation of the oil composition from five of the seven distinct localities studied all contains 1,8-cineole and limonene as major constituents. The antimicrobial study of these samples indicated little variability between localities (standard deviation of ±0.5 to ±3.8). As observed in the seasonal variation study, C. neoformans displayed the highest sensitivity (0.5–2.0 mg/ml). One oil sample (Lagalametse), was distinctly different both chemically and microbiologically.

Modern sedentary lifestyles, an increase in the consumption of nutrient dense foods and declining levels of participation in physical activity progressing from childhood to adulthood have been implicated in the occurrence of many hypokinetic diseases including obesity and coronary artery disease (CAD). Despite this quality health and physical education (PE) programmes are not employed as a proactive preventative measure to address this issue. The purpose of this study was therefore to investigate, using qualitative methods, the perceptions of grade 10 learners with regard to PE at schools and make recommendations thereon. Informal focus group interviews were conducted with 68 Grade 10 learners (n = 39 males and 29 females) from different high schools in Gauteng, South Africa. The interviews were conducted outside the formal classroom situation and PE lesson to access information regarding the perceptions of learners with regard to physical education (PE). Several underlying themes which included value, enjoyment, support, preferred PE activities and obstacles to involvement in physical activity emerged from the study. The descriptive information demonstrated that future physical education educators should be adequately prepared to guide their learners in the process of becoming physically active and healthy for a lifetime by focusing on lifetime activities and health-enhancing behaviors linked to health concepts and skills such as healthy eating, safety and stress management with less emphasis on athletic skills.

A laboratory incubation study was conducted to determine the effects of liming on microbial activity and N mineralization in two Bizana soils amended with broiler manure. The experimental layout was a 4 x 3 complete factorial experiment with three replicates, arranged in a randomized design. Soil pH, CO2 evolution, and mineral N concentration were measured. After 56 days the soil pH ranged from 4.50 to 5.74 and 4.99 to 5.94, in the Magusheni and Nikwe soils, respectively. The effect of liming on microbial activity and N mineralization differed between the soils. In the Nikwe soil (acid saturation 4.0%), microbial activity and N mineralization increased as the rate of broiler manure application was raised, but liming had no effect. In the Magusheni soil (acid saturation 25%), microbial activity increased as both lime and chicken manure application rates increased, but liming reduced N mineralization, suggesting N immobilization was being driven by an active microbial population in the limed soils. The rates of lime and/or chicken manure application, percentage Ca2+ and soil acid saturation were important factors influencing microbial activity and N mineralization, but the effect of soil pH on N mineralization was not evident in either of the soils.