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This study aimed to assess the variations in the nutritional attributes of thirteen Moringa oleifera cultivars. Leaves from six-month-old plants were harvested and tested for various nutritional attributes. There were significant (p ≤ 0.05) differences in the carbohydrates, energy, some of the sugars, and fibre amongst the cultivars. The levels of moisture in the cultivars ranged from 7.10% to 8.20%. Additionally, there were significant (p ≤ 0.05) differences across the cultivars in microelements studied except for zinc (Zn). These data revealed that plants from different geographical provenances differed in their adapting to varied environments. In general, under the same cultivation, management, and environmental conditions, the main reasons for these differences occurring in cultivars could be associated with the genetic background of each M. oleifera germplasm. However, the study cautions on the differences in nutritional properties, as some of the cultivars have been reported not to be pharmacologically potent.

A study was conducted to assess variation in antioxidant, antimicrobial, antidiabetic and phytochemical properties between the leaves, and the main and lateral roots of Moringa (Moringa oleifera). Standard antioxidant models including the DPPH scavenging, ferric reducing power (FRAP) as well as α-glucosidase inhibitory activity were used to evaluate and compare their bioactivity. Antimicrobial efficacy was also tested against Gram-positive (Staphylococcus aureus; Bacillus subtilis) and Gram-negative (Escherichia coli) strains and the yeast-like fungus Candida albicans using the microdilution method. Acetone extracts of all plant parts exhibited good antibacterial activity (MIC 1 mg/mL). However, all the plant part extracts exhibited low activity against C. albicans (MIC values

Improving plant germination is essential to guarantee better quality seedlings. Thus, this research aimed to evaluate whether the seed priming with light quality (LIQ) and the aqueous extract of Cyperus rotundus (AEC) tuber could modulate the germination and initial growth of Moringa oleifera L. seedlings. The experimental design was a completely randomized in the 4x4 factorial scheme, composed of four LIQ conditions (white, blue, red, and distant red light) and four AEC concentrations (0, 25, 50 and 100%). Seed priming with red light reduced the average emergence time, while blue, red, and extreme red lights associated with 50% of aqueous extract of C. rotundus increased shoot initial length and photosynthetic pigment accumulation. Seed priming with blue light resulted in seedlings with a shorter final shoot length. However, application of 100% of aqueous extract of C. rotundus reversed this. The white light in combination with concentrations of 50 and 100% of AEC promoted a higher relative shoot growth rate of seedlings. The research revealed that seed priming with light quality and aqueous extracts of C. rotundus tubers modulates the germination and initial growth of M. oleifera seedlings. More work needs to be done to determine the responsible compounds in AEC that is responsible for priming growth as phytohormones. Resumo A melhoria da germinação de plantas é fundamental para garantia de mudas de melhor qualidade. Assim, objetivou-se avaliar se o condicionamento de sementes com qualidade de luz (light quality - LIQ) e extrato aquoso de tubérculos de Cyperus rotundus (AEC) modula a germinação e o crescimento inicial de plântulas de Moringa oleifera. Utilizou-se delineamento inteiramente casualizado, em esquema fatorial 4x4, sendo quatro condições de LIQ (luz branca, azul, vermelha e vermelho distante) e quatro concentrações de AEC (0, 25, 50 e 100%). O condicionamento de sementes com luz vermelha reduziu o tempo médio de emergência, enquanto que as luzes azul, vermelha e vermelho extremo associadas a 50% de extrato aquoso de C. rotundus aumentaram o comprimento inicial da parte aérea e o acúmulo de pigmentos fotossintéticos. Condicionamento de sementes com luz azul induziu a formação de plântulas com menor comprimento final da parte aérea, no entanto, a aplicação de 100% de extrato aquoso de C. rotundus reverteu o menor crescimento. A luz branca associada às concentrações de 50 e 100% de fitormônios promoveu maior taxa de crescimento relativo da parte aérea de plântulas. Nossa pesquisa mostra que o condicionamento de sementes com radiação espectral de luz e extrato aquoso de tubérculos de Cyperus rotundus modula a germinação e o crescimento inicial de plântulas de Moringa oleifera. Mais trabalhos precisam ser feitos para determinar os compostos do AEC responsáveis que que atuam como fitormônios e são responsáveis pelo crescimento inicial.

The progression of age and dark spots on human skin is undesirable as it indicates the reduction of skin beauty. The melanin produced by melanocytes is responsible for the associated darkening of the skin. Tyrosinase modulates the melanogenesis process and is a therapeutic target for skin disorders such as hypopigmentation and hyperpigmentation. The aim of the study was to evaluate the efficiency of plant extracts in maintaining the cells health and tyrosinase enzyme function using a human epidermal melanocyte (HEM) cell line. Ethanol extracts of Cassipourea flanaganii (Schinz) Alston, Chenopodium album L., Clausena anisata (Willd.) Hook.f ex Benth and Rorippa nasturtium-aquaticum (L.) Hayek were observed to be non-toxic to melanocytes at a concentration of 15 μg/mL. There was no significant difference between the extracts and the positive control in inhibiting cellular tyrosinase activity with IC50 values ranging between 1.42 and 1.55 μg/mL. The observed anti-tyrosinase activity of the plant extracts against the cell lines contribute positively in achieving the desired skin complexion while providing photo protection. Therefore, plant extracts that are efficient and safe to use can be incorporated into formulations intended for beauty enhancement.

Objectives: This study determined caregivers’ (mothers’) acceptability and perceptions of a soft, white maize porridge (traditional complementary food (TCF)) that was modified by substituting maize meal with Moringa oleifera Lam. leaf powder at different levels, 1%, 2% and 3% weight for weight (w/w). Design: A cross-sectional study was conducted. Setting: The study was conducted in Stinkwater, Hammanskraal, Gauteng province (25° 23’ 59.99” S: 28° 16’ 60.00” E) and Ga-Mphahlele village, Lebowakgomo, Limpopo province (24°18’0.83”S: 29°32’33.61”E), South Africa. Subjects: Sixty mothers were sampled, separately, from Hammanskraal and Lebowakgomo communities. Outcome measures: The sensory acceptability of the complementary soft porridges was evaluated by caregivers from Hammanskraal and Lebowakgomo communities using a five-point facial hedonic scale (n = 60 per study area). A series of three focus-group discussions were conducted per study area (n = 12 persons per group) to assess caregivers’ perceptions on the inclusion of moringa in complementary foods. Results: Sensory evaluation results showed that the acceptability of the two traditional complementary foods decreased as the level of moringa leaf powder increased. Caregivers indicated in the focus-group discussions that moringa-based soft porridges had a bitter taste, which would not be suitable for children. Only the Lebowakgomo modified traditional complementary food (MTCF) containing 1% of moringa was rated similar in overall acceptability to the corresponding TCF (control). Nevertheless, all caregivers expressed willingness to use moringa in complementary foods provided they would be trained on how to process it. Conclusions: Varying product formulation and processing methods may contribute to increased acceptability of moringa-based foods. Overall, moringa appears to have the potential for use in complementary foods.

Amandla impilo immune booster and sejeso are two widely used South African commercial herbal remedies that are prepared from a mixture of several plants. They are used as multipurpose treatments for curing various diseases and ailments including gastrointestinal disorders, and diabetes (amandla impilo). This study was aimed at determining the pharmacological potential of the two herbal remedies, and eleven constituent plant species used in their preparation. Water and 70% aqueous acetone were used for extraction, and 30 extracts in total were evaluated for antibacterial activity against Campylobacter jejuni, Escherichia coli, Shigella flexneri and Staphylococcus aureus from the American Type Culture Collection. Extracts that exhibited antibacterial activity with minimum inhibitory concentration (MIC) values less than 1 mg/ml against at least three bacterial strains were evaluated for cytotoxicity against monkey kidney (Vero) cells. Amandla impilo immune booster and its plant constituents were evaluated for antidiabetic potential against the alpha-glucosidase enzyme. The MIC values ranged from 0.195–12.50 mg/ml, and the best value was demonstrated by 70% aqueous acetone extracts of Elephantorrhiza burkei roots against S. aureus and S. flexneri as well as Peltophorum africanum bark and leaves against S. flexneri (MIC = 0.195 mg/ml). The 70% aqueous acetone leaf extracts of Gunnera perpensa and P. africanum, as well as the water extract of Hypoxis obtusa corms were not toxic to Vero cells. However, 70% aqueous acetone extracts of E. burkei roots, H. obtusa corms and P. africanum bark showed slight toxicity towards the cells, and thus should be administered cautiously. Amandla impilo immune booster exhibited stronger alpha-glucosidase inhibitory activity (40.08 μg/ml) than the positive control, acarbose (1040.00 μg/ml), providing credence for the antidiabetic use of this concoction. Interestingly, water extracts of G. perpensa leaves and rhizomes (2.61 and 2.72 μg/ml respectively), 70% acetone extracts of G. perpensa leaves (5.69 μg/ml), Watsonia densiflora bulbs (9.08 μg/ml), Combretum krausii bark and leaves (19.38 μg/ml), G. perpensa rhizomes (18.00 μg/ml), W. densiflora bulbs (14.82 μg/ml) and Mimusops obovata bark (17.25 μg/ml) showed stronger inhibition of the enzyme, demonstrating more antidiabetic potential individually than the commercial mixture they make. In conclusion, the observed antibacterial and antidiabetic activity of some plants, if supported by further studies, might justify their inclusion in the makeup of the tested herbal remedies. Although amandla impilo and sejeso showed low antibacterial activity, more research determining potential toxicity and antibacterial activity against bacterial strains, not tested in this study, is required as these two concoctions are used in traditional medicine practice against various diseases. This study confirmed the antidiabetic potential of amandla impilo, therefore, further studies on its antidiabetic activity and possible synergistic potential due to mixing of plant extracts are required.

BackgroundMoringa oleifera seed has anti-diabetic and anti-obesogenic properties. This study interrogated the effect of crude hydroethanolic M. oleifera seed extract on the blood markers of metabolic syndrome (MetS) in high-fructose diet fed growing Sprague-Dawley rats.MethodsSixty 21-day old female and male Sprague-Dawley rat pups were randomly allocated to and administered one of the following treatment regimens daily for twelve weeks: group I – plain drinking water (PW)+plain gelatine cube (PC), group II – 20% (w/v) fructose solution (FS)+PC, group III – FS+100 mg/kg body mass fenofibrate in gelatine cube (FN), group IV – FS+low dose (50 mg/kg body mass) of M. oleifera in gelatine cube (LMol) and group V – FS+high dose (500 mg/kg body mass) of M. oleifera in gelatine cube (HMol). The rats in each treatment regimen had ad libitum access to a standard rat chow. After the 12-week trial, the rats were subjected to an oral glucose tolerance test and then euthanised 48 h later. Blood was collected. Plasma triglyceride, cholesterol and insulin concentration were determined. HOMA-IR was then computed.ResultsThe high-fructose diet increased (pM. oleifera seed extract prevented the high-fructose diet-induced metabolic derangements in male and female rats.ConclusionCrude hydroethanolic M. oleifera seed extract can potentially be used as a prophylactic intervention for diet-induced MetS in children.

Nutritional manipulations in the neonatal period are associated with the development of negative or positive health outcomes later in life. Excessive fructose consumption has been attributed to the increase in the global prevalence of metabolic syndrome (MetS) and the development of oxidative stress. Oleanolic acid (OA) has anti-diabetic and anti-obesity effects. We investigated the protective potential of orally administering OA in the neonatal period, to prevent fructose-induced oxidative stress, adverse health outcomes and maturation of the gastrointestinal tract (GIT) in suckling rats. Seven-day old Sprague-Dawley rats (N = 30) were gavaged daily with 10 mL/kg of: distilled water (DW), oleanolic acid (OA, 60 mg/kg), high fructose solution (HF, 20% w/v), or OAHF for 7 days. On day 14, tissue samples were collected to determine clinical health profiles, hepatic lipid content, and activity of anti-oxidant enzymes. Furthermore, biomarkers of oxidative stress and anti-oxidant capacity in the skeletal muscles were assessed. The gastrointestinal tract (GIT) morphometry was measured. Rats in all groups grew over the 7-day treatment period. There were no significant differences in the terminal body masses, GIT morphometry, surrogate markers of general health, liver lipid content across all treatment groups (p &lt, 0.05). Neonatal fructose administration decreased the activity of catalase, depleted GSH and increased lipid peroxidation. However, the level of GSH and catalase activity were improved by neonatal OA treatment. Short-term oral OA administration during the critical developmental period protects against fructose-induced oxidative stress without adverse effects on health outcomes associated with MetS or precocious development of the GIT in suckling male and female rats.

The processes of semen cryopreservation and thawing affect sperm membrane integrity and motility and increases morphological defects as well as DNA damage. The most influential cause of this is oxidative stress. When endogenous antioxidant capacity of seminal plasma is reduced during the freeze-thawing process, plant extracts exhibiting strong antioxidant activity can be used as supplements for compensation. Baobab oil has gained interest because it is rich in powerful antioxidants, which could protect sperm cells from oxidative damage during cryopreservation. Our study aimed to assess the effects of baobab oil on post-thaw sperm quality parameters in an egg-yolk-based extender. Thirty semen ejaculates were collected from 15 Nguni bulls using an electro ejaculator. Semen samples were randomly allocated to control (no baobab oil), 20μL (1%), 50μL (2.5%), and 100μL (5%) baobab oil per millilitre extender. Following dilution, semen samples were loaded into 0.25-mL semen straws, equilibrated for 4h at 5°C, and transferred into a controlled rate programmable freezer. The frozen semen straws were stored in a liquid nitrogen tank (−196°C) until thawing. Semen straws were thawed (37°C/60 minutes) after 1 week of cryopreservation and analysed for (1) sperm motility using a computer-aided sperm analyser, (2) morphological defects and viability using eosin-nigrosin stain, (3) membrane integrity by hypo-osmotic swelling test, and (4) DNA integrity by terminal deoxynucleotidyl transferase dUTP nick end labelling assay. Data was analysed using analysis of variance. Treatment means were compared in relation to the control group by Dunnett's test. We found that supplementing semen extender with baobab oil at 1% significantly (P

The indigenous people from Limpopo regard herbal remedies as the most effective way of treating Sexually Transmitted Infections (STIs). There are several herbal remedies that they use for various purposes. This study was aimed at evaluating the efficacy of a popular herbal remedy used to treat STIs by testing for its antimicrobial activity, enzyme inhibition against HIV-type 1 reverse-transcriptase (HIV-RT) and cyclooxygenase (COX-2). The safety of the remedy was evaluated by testing for its mutagenic and anti-mutagenic effects. The herbal remedy evaluated in this study was manufactured by a traditional healer from Madiwana village in Limpopo province, South Africa. The mixture was derived from nine plant species, which were also evaluated individually. The herbal remedy was evaluated for its antimicrobial properties against two Gram-positive (Bacillus subtilis and Staphylococcus aureus), three Gram-negative (Neisseria gonorrhoeae, Escherichia coli and Klebsiella pneumoniae) bacteria and a fungus, Candida albicans. It was assessed for its pharmacological and genotoxicity properties. The extracts of the nine plant species were evaluated in the antigonococcal bioassay only. The herbal remedy exhibited moderate activity against N. gonorrhoeae (66%) but showed good activity against E. coli, K. pneumoniae and S. aureus with MIC values ranging from 0.78 to 1.56 mg/ml. The mixture exhibited low antifungal activity against C. albicans. The remedy exhibited insignificant and moderate activities against COX-2 and HIV-RT respectively. The remedy was non-mutagenic. Acetone extracts of Catharanthus roseus, Senna italica, Gomphocarpus fruticosus and Solanum panduriforme showed the best antigonoccol activity > 70%. The observed activities of the herbal remedy may offer a lead to explore new multi-target drugs against gonorrhoea and other STIs.

In Africa, the use of medicinal plants to combat diseases forms an integral component of the culture and is thus practised widely. To this extent, several important plant species have been subjected to different pharmacological screening techniques to give scientific credence to the claimed uses. Among those that have been screened are those used to combat oxidative stress. We present here a review of the important plants used in African traditional medicine with antioxidant potential. The plants listed here are habitats of North Africa, covering the vast Sahara, West Africa, East Africa and the Palaeotropical kingdom of Central Africa as well as Southern Africa including the Capensis kingdom of the Western Cape province of South Africa, Madagascar, Mauritius and the Mascarenes. Oxidative stress has been implicated as one of the key factors in accelerated pathogenesis of a number of human diseases including cardiovascular, inflammatory, cancer, autoimmune and neurodegenerative diseases. Plants listed here have been utilised directly or indirectly in managements of some of these conditions.

A study was undertaken to assess variation in antioxidant, antimicrobial and phytochemical properties of thirteen Moringa oleifera cultivars obtained from different locations across the globe. Standard antioxidant methods including the DPPH scavenging, ferric reducing power (FRAP) and β-carotene-linoleic acid model were used to evaluate the activity. Variation in the antioxidant activity was observed, with TOT4951 from Thailand being the most active, with activity five times higher than that of ascorbic acid (reference compound). A different trend was observed for the activity in the FRAP and β-carotene-linoleic acid assays. Antimicrobial activity was tested against Gram-positive (Staphylococcus aureus) and Gram-negative (Klebsiella pneumoniae) strains using the microdilution method. Acetone extracts of all cultivars exhibited good antibacterial activity against K. pneumoniae (MIC values of 0.78 mg/mL). The remaining extracts exhibited weak activity against the two microorganisms. For the antifungal activity, all the extracts exhibited low activity. Variations were observed in the total phenolic and flavonoid contents. Cultivars TOT5169 (Thailand) and SH (South Africa) exhibited highest amounts of total phenolic compounds while TOT5028 (Thailand) exhibited the lowest amounts of five times lower than the highest. The information offer an understanding on variations between cultivars from different geographical locations and is important in the search for antioxidant supplementation and anti-ageing products.

Ethnopharmacological relevance Hypoxis species (Hypoxidaceae) are popular medicinal plants used in the African traditional medicine to treat numerous ailments and are reported to have a wide spectrum of pharmacological properties. In this paper we reviewed and evaluated the traditional uses, pharmacological, phytochemistry and toxicity aspects of the genus Hypoxis. Potential medicinal prospects and possible knowledge gaps and pitfalls are discussed. Materials and methods A comprehensive and systematic review of literature on Hypoxis species was done using numerous resources such as books and scientific databases that include Pubmed, Scopus, Scirus, Google scholar, Web of Science and others. Information on the various pharmacological and chemical properties of Hypoxis extracts was critically analysed and discussed under the various topics. Results The literature indicated a broad range of uses, pharmacological and toxicological properties of different Hypoxis species extracts and their relevance to African healthcare systems. Several compounds, mostly glucosides, sterols and sterolins, have been isolated, identified and tested in various in vitro and in vivo models as well as in a couple of clinical trials with a lot of promising prospects reported in some studies. Conclusion A critical analysis of the available literature and studies identifies positive potential for the future use of Hypoxis species in both traditional and modern medicine and concurrently so with possible pitfalls and research gaps in current knowledge. An integrated and holistic approach to addressing research issues, particularly toxicology aspects could be more effectively applied and incorporate conservation strategies for the species.

Ethnopharmacology relevance Hypoxis species are used extensively in traditional medicine in southern Africa for several ailments including tuberculosis, chest infections, and nervous and urinary disorders. Several other claims have been made for extracts emanating from Hypoxis species and have led to the production of several commercial products used as immunostimulants mostly for people living with HIV/AIDS and cancer. This study was aimed at investigating the biological activity of four Hypoxis species and a commercial herbal product, ‘African potato extract’ (APE). Materials and methods Antibacterial, antifungal, cyclooxygenase (COX) and acetylcholineasterase (AChE) inhibitory activities of four Hypoxis species (H. acuminata, H. colchicifolia, H. hemerocallidea and H. rigidula) and a popular Hypoxis-based herbal preparation, APE were tested. The phytoconstituents of the mixture were also profiled using TLC methods. Several combinations of the Hypoxis species were prepared and their synergism, additive, autonomic and antagonism effects investigated. As a quality control measure, batch to batch comparison in the phytoconstituents and biological activity of APE was carried out. Results The results confirmed H. colchicifolia and H. hemerocallidea as the phytoconstituents of APE. The extracts showed a broad spectrum of activities against the bacterial and fungal strains used. Of particular interest were the activities exhibited by the APE and combinations of H. colchicifolia and H. hemerocallidea. The APE mixture exhibited good antibacterial activity (MIC values of 0.78 mg/ml each) in all the tested batches against the bacterial strains used. The water extracts of all four Hypoxis species, three batches of APE and the combination (water extracts) of H. colchicifolia and H. hemerocallidea exhibited high COX-1 and moderate COX-2 inhibitory activity except for H. acuminata which showed low activity against COX-2. All the extract, batches of APE and combinations showed low to moderate AChE inhibitory activity. These results provided some evidence of phytosynergy in some extracts of H. hemerocallidea and H. colchicifolia except for a few extracts which act as additive, autonomous and antagonistic when used to inhibit some bacterial and fungal strains. However, this was not the case for COX and AChE inhibition, as only acetone extracts acted in a synergistic way to reduce the activity of the enzyme. Conclusion Even though the results give an indication of a positive interaction between some extracts of H. hemerocallidea and H. colchicifolia, the study was carried out on 1:1 v/v combinations only. It is therefore important to carry out isobologram studies, which considers more than one ratio of the combinations.

Ecklonia maxima, a brown alga grows abundantly on the west coast of South Africa and is used to produce alginate, animal feed, nutritional supplements and fertilizer. The crude extract, solvent fractions and phlorotannins isolated from E. maxima were evaluated for acetylcholinesterase (AChE) inhibitory activity using the microplate technique. The IC50 values for the solvent fractions ranged from 62.61 to 150.8 μg/mL, with the ethyl acetate fraction having the best inhibitory activity against AChE. Repeated column fractionation of the ethyl acetate fraction on Sephadex LH-20 resulted in isolation of three compounds identified as: 1,3,5-trihydroxybenzene (phloroglucinol) (1), together with two of its derivatives dibenzo [1,4] dioxine-2,4,7,9-tetraol (2) and hexahydroxyphenoxydibenzo [1,4] dioxine (eckol) (3). The spectra data of compound 2 is reported for the first time. Structure elucidation of the isolated compounds was carried out using spectroscopic techniques: mass spectrometry (ESI-TOF-MS), 1H and 13C NMR, DEPT together with 2D experiments (GCOSY, GHSQC and GHMBC). The IC50 values for the compounds ranged from 76.70 to 579.32 μM, with compounds 2 and 3 having the best AChE inhibitory activity. The activity demonstrated by the extracts and the isolated compounds suggests that they could be used as functional food ingredients for the management of neurodegenerative disorders.

Croton penduliflorus is a medicinal plant widely employed in the management of inflammatory conditions, infections and oxidative stress related diseases. The activities demonstrated by leaf extracts indicate that they possess the ability to reduce oxidative damage to cells. Repeated column fractionation of the ethyl acetate fraction of a 20% aqueous methanol leaf extract of C. penduliflorus on Sephadex LH-20 afforded four phenolic compounds: quercetin-3-O-rhamnoside (1), kaempferol-3-O-rhamnoside (2), protocatechualdehyde (3A) and its solvent derived dimer (3B) along with p-hydroxybenzoic acid (4). Compound 3B is described for the first time and its significance in bioassay is briefly outlined. Structure elucidation of the isolated compounds was carried out using spectroscopic techniques. The inhibitory properties of the four compounds against acetylcholinesterase were determined using the microplate assay. The IC50 values of the isolated compounds ranged from 87.9 to 1231.9 μM, with compound 2 having the best inhibitory activity (IC50 = 87.9 μM). The four isolated compounds showed no mutagenic effects against Salmonella typhimurium tester strains TA98 and TA100. The moderate activity demonstrated by these compounds suggests that they could be helpful in the management of neurodegenerative disorders.

Biological activities of petroleum ether (PE), dichloromethane (DCM), 70% ethanol (EtOH) and water extracts of Botanical Garden-grown (BG) and muthi market-sourced (MM) Bowiea volubilis bulbs were compared. Bulb extracts were subjected to the microdilution technique using five test organisms for antimicrobial activity and cyclooxygenase (COX-1 and -2) inhibition as well as the Ames test for potential mutagenicity. Overall, both the MM and BG bulb extracts demonstrated a comparatively weak antimicrobial potency. The best minimum inhibitory concentration (MIC: 1.56 mg/ml) was detected in the MM bulb water extract against Candida albicans . In both MM and BG bulbs, 63% of the extracts, particularly the non-polar solvent extracts, exhibited a high (> 70% inhibition) COX-1 and -2 inhibitory activity. Both MM and BG bulb extracts were not mutagenic against the Salmonella typhimurium TA98 tester strain. Current findings indicate the potential substitution of cultivated B . volubilis bulbs (BG) for the wild population (MM) which is often utilized and preferred in traditional medicine. Inevitably, this will contribute to the conservation of the species as the strain on the wild population due to overharvesting will be alleviated.

A comparative evaluation of the antioxidant and acetylcholinesterase inhibitory activity of the leaf extracts of Croton gratissimus and Croton zambesicus (subgratissimus) and compounds isolated from the extracts was carried out to determine their potential and suitability or otherwise as a substitute for each other in the management of oxidative and neurodegenerative conditions. Different antioxidant assays (DPPH, FRAP, β-carotene-linoleic and the lipid peroxidation models) and the microplate assay for acetylcholinesterase (AChE) inhibition were carried out separately to study the activities of the crude leaf extracts and four solvent fractions from each of the two Croton species. Bioassay guided fractionation was used to target antioxidant constituents of the crude extracts and ethyl acetate fractions of 20% aqueous methanol extract of C. gratissimus on silica gel and Sephadex LH-20 columns resulted in the isolation of kaempferol-3-O-β-6''(p-coumaroyl) glucopyranoside (tiliroside, 2), apigenin-6-C-glucoside (isovitexin, 3) and kampferol (4). The extract of C. zambesicus yielded quercetin-3-O-β-6''(p-coumaroyl) glucopyranoside-3'-methyl ether (helichrysoside- 3'-methyl ether, 1), kaempferol-3-O-β-6''(p-coumaroyl) glucopyranoside (tiliroside, 2) and apigenin-6-C-glucoside (isovitexin, 3). Three of the isolated compounds and their different combinations were also included in the bioassays. In all the assays performed, the antioxidant capacity and AChE inhibitory effects of C. zambesicus extracts were weaker than those of C. gratissimus. This suggests that C. gratissimus may not be substituted by C. zambesicus, despite the similarity in some of their constituents. Generally, the combinations made from the isolated compounds showed better activities in most of the assays compared to the individual isolated compounds. This suggests mechanisms such as synergism and/or additive effects to be taking place. This study established low, moderate and high antioxidant activities as well as AChE inhibitory effects by the crude extracts, fractions, compounds and compound combinations. This means some of the extracts, isolated compounds and compound combinations could be useful in the management of neurodegenerative conditions and serve as sources of natural neurodegenerative agents.

There is a proliferation in the use of commercial herbal preparations, most notably liquid preparations of plant material packaged in plastic containers. The quality of these herbal preparations has always and still remains questionable. A number of research institutes and research groups in tertiary institutions throughout South Africa have embarked on the development of quality control programmes to test herbal medicines for safety and efficacy. However, very few of these groups have placed any emphasis on commercial herbal mixtures. This paper describes some effects of toxic phthalates such as bis(2-ethylhexyl) phthalates, (a common plasticiser) used in cheap soft plastics and its metabolites. Analytical methods for the determination, quantification and monitoring of DEHP in herbal remedies to ensure safety are also highlighted.

In South Africa, the use of commercial herbal concoctions is becoming very popular. However, due to lack of Good Manufacturing Practices there is a possibility of heavy metal contamination in these commercial herbal concoctions. The aim of this investigation was to screen for heavy metal and trace elements in commercial herbal concoctions used in traditional medicine to treat various kinds of ailments in South Africa. This is the first investigation in which metal concentrations in commercial herbal concoctions was measured. Fourteen herbal concoctions were obtained from traditional herbal (muthi) shops and were subjected to analysis for total and bioavailable metal concentrations using Inductively Coupled Plasma-Optical Emission Spectrophotometry (ICP-OES). Of all the concoctions tested only Vusa umzimba and Sejeso herbal mixture contained high amounts of Cd (2.2 and 0.6 mg/kg) respectively, exceeding the safety limit of 0.3 mg/kg (WHO, 1998). Vusa umzimba also exhibited high amounts of bioavailable Cd (1.2 mg/kg) thereby making it unsafe for human consumption. Surprisingly very high amounts of Hg were detected in Ingwe muthi mixture and Sejeso herbal mixture (14.9 and 12.3 mg/kg) respectively. These by far exceeds the weekly allowance limit of 2 μg/kg given by WHO/UN committee (2007). Relatively high amounts of Pb were found in Sejeso herbal mixture. The levels of bioavailable metals detected in this study raise concerns, not only for consumer safety, but also the quality of herbal concoctions available as part of the traditional medicinal practice in South Africa. © 2012 SAAB. Published by Elsevier B.V. All rights reserved.

This review aims to clear off or bring to the public, any unsubstantiated (smokescreens and mirrors) claims made by manufacturers of commercial herbal products (CHP) in South Africa. The review further examines production, quality in terms of efficacy and safety as claimed by the manufacturers and seeks to understand any possibilities of adulteration with modern medicine to these so called African products. There is evidence of an increase in locally produced CHP containing complex mixtures of several medicinal plants, sold in numerous retail outlets, including supermarkets and pharmaceutical outlets. The CHPs are available in liquid, capsule and powder forms, packaged professionally, carrying labels that lists conditions these preparations are used for. Some of the labels list the plant species in the product and in some cases vitamins and essential elements used for fortification.

We performed an in vitro evaluation of the genotoxic potential of water extracts from four Hypoxis species (Hypoxis hemerocallidea, H. colchicifolia, H. rigidula, H. acuminata) and a commercial preparation thereof using the neutral red uptake (NRU) assay, the alkaline comet assay and the cytome assay in human hepatoma HepG2 cells. The relative cytotoxicity of these samples was established by determining their NI50 values (50% inhibition of NRU), and these results were used for dose-finding in genotoxicity tests. None of the tested extracts were identified as genotoxic in both the alkaline comet assay and cytome assay. Copyright © 2012 John Wiley & Sons, Ltd.

Eucomis autumnalis (Mill.) Chitt produces bulbs that are used to treat a variety of ailments in South African traditional medicine. E. autumnalis is a sought after herb which is fast becoming over-exploited and threatened in the wild. The effects of sunlight intensity, temperature, watering frequency and smoke-water solutions on the seedling and bulb development of E. autumnalis were investigated. Sunlight intensity of 50% achieved the best developed seedlings and bulb sizes compared to 75% and 100% sunlight. The optimum temperatures for seedling development of E. autumnalis were found to be 30/15 °C (alternating day/night temperatures). A regular watering frequency (three times per week) produced the largest bulbs compared to less frequent watering. Smoke-water solution at a 1:250 v/v dilution stimulated growth and produced the largest bulbs when compared to dilutions of 1:500 and 1:1000 v/v smoke-water. These conditions are therefore recommended for rapid propagation of E. autumnalis . The pharmacological properties of the bulbs exposed to different light conditions, temperature regimes, watering frequencies and smoke-water solutions of E. autumnalis were also investigated against two Gram-positive, two Gram-negative bacteria and a fungus Candida albicans . The extracts were also evaluated for their inhibitory effects against cyclooxygenase (COX-1 and -2) enzymes. The results revealed some increases in the bioactivities of some of the extracts from the bulbs exposed to different light conditions, temperature regimes, watering frequencies and smoke-water solutions compared to the control bulbs. High antimicrobial activity was observed in the acetone extracts compared to the water extracts. Full light exposure (100%) and watering frequency of once per week exhibited the best minimum inhibitory concentration (MIC) values against Bacillus subtilis while sunlight exposure of 75 and 100% as well as smoke-water solution of 1:500 (v/v) exhibited the best activities against Staphylococcus aureus . In the COX-2 bioassay, the acetone extracts of the bulbs exposed to different light conditions, temperature regimes, watering frequencies and smoke-water solutions showed higher inhibitory properties compared to the control bulbs. However, there were no significant differences in the inhibitory properties of the bulbs exposed to different light conditions, temperature regimes, watering frequencies and smoke-water solutions and the control bulbs in COX-1 bioassay. It is important to carry out studies on the effects of these treatments on the genotoxicity and toxicity of E. autumnalis bulbs as well as investigating the variations in their phytochemical properties.

The modern trend in traditional medicines reflects an increase in the sale of complex herbal mixtures rather than those prepared from single plants. This trend is well documented in Traditional Chinese Medicine (TCM) and can be seen in recent developments in African traditional medicine. An increase in the prevalence of locally produced herbal preparations, especially those containing complex mixtures of several medicinal plants, sold in numerous retail outlets, including supermarkets and pharmacies has been observed. The appearance of these preparations is not surprising in rapidly urbanizing societies where traditional products are still desired but the users have neither the time nor resources to produce them. The production of these herbal mixtures has resulted in a growing herbal industry with about 50 to 100 private entrepreneurs in the informal market and has also contributed to creation of numerous jobs. The products are extensively advertised in newspapers, on the internet, television and radio programmes as well as through pamphlets and posters. This review examines and documents the prevalence of commercial herbal mixtures and preparations common in Pietermaritzburg, KwaZulu-Natal. Different types of herbal mixtures, claims, ethical and legal implications are discussed. Methods of preparation and marketing strategies as well as the way forward in ensuring economic impact, safety and efficacy of this new aspect of South African traditional medicine are also highlighted.