Length Research Paper Effects of pre-chilling and temperature on seed germination of Corchorus olitorius L. (Tiliaceae) (Jew’s Mallow), a wild leafy vegetable

The wild leafy vegetable, Corchorus olitorius L, has a potential for development as a crop. Self propagation of this species is by seed. In an attempt to improve the length of time of its availability, theeffects of pre-chilling and temperature on germination of its seeds were investigated. Although it had a seed viability of 90.1% (using the tetrazolium technique), seed subjected to a temperature of 25oC forboth pre-chilled and unchilled seeds showed no germination. Seeds subjected to a temperature of 35oC did germinate with a maximum of 88% germination from seeds that had been pre-chilled for 3 ½ dayscompared to those which were unchilled, pre-chilled for a day or pre-chilled for 7 days. Pre-chilling followed by exposure to a temperature higher than 30oC encourages germination of C. olitorius seeds. Nursery establishment under such conditions may improve its length of availability

An alternative health crop for South Africa: Purple potato mini tuber production as affected by water and nutrient stress

Food security in South Africa ranks as one of the top ten priorities in the country. Potato is a fundamental staple food crop in South Africa, providing essential nutrition. While there are several cultivars currently in production for the potato market, there is a need to explore cultivars that are available, but not utilised within the country. Pigmented potatoes are not regarded as high value on the South African market; however, yield prospects as well as health-promoting benefits could have a positive contribution on the South African Gross Domestic Product (GDP) and on the population’s health. Potato cultivar (cv.) Salad blue (SB) seems to be a drought-tolerant crop with the ability to produce reasonable yields under severe environmental conditions. In order to promote cv. SB as a possible food security option for South Africa, there is a critical need for empirical information, describing some basic horticultural as well as  biochemical information and vitamin C presence. This study investigated the potential of pigmented potato SB tubers as an alternative to high yielding white potato for the South African market. Tubers of Solanum tuberosum cv. BP1 and SB, were used for this research. The high amounts in phenolic compounds in SB can be considered to be health-promoting phytochemicals. Anticarcinogenic,  antibacterial, antiviral properties have been reported. A greenhouse, bag trial with virus-free plantlets of BP1 and SB cultivars was conducted using three water and nutrient levels and favourable root zone temperature (100% without heat, 100% heated, 50% heated, 25% heated) all grown in coco peat. Cultivar SB showed nearly two-fold yield compared to the control BP1. Methanol extracts of the tubers were assessed for their total polyphenolic, flavanol, and flavonol contents as well as 1-diphenyl-2-picrylhydrazyl (DPPH)  scavenging ability, ferric reducing antioxidant power (FRAP), Trolox equivalence antioxidant capacity (TEAC), anthocyanin and Lascorbic acid assays. The aqueous extract of the SB tubers was found to contain higher level of total polyphenols (320 mg GAE/g), and flavonol (85 mg QE/g) than the extract of the BP1 tubers with values of 173 mg GAE/g (total polyphenol), and 67 mg QE/g (flavonol). Similarly, the methanol extract of the tuber skins also exhibited higher DPPH (818,86 IC50 mg/mL), FRAP (18,19 μmol AAE/g), and TEAC (911,12 μmol TE/g) than the extract of the BP1 with DPPH (595,99 IC50 mg/mL), FRAP (10,86 μmol AAE/g) and TEAC (435,44 μmol TE/g). The present study provides useful information for farmers and health professionals in respect to increased yield and health-promoting benefits of an underutilized potato variety. Key words: Drought tolerant, Food security, Potato, Root Zone Temperature, water, nutrien

Cytotoxicity of selected medicinal plants used in Mt. Frere District, South Africa

Background: In South African traditional medicine, some are plants known to combat pediatric diseases and are commonly used by traditionalhealers. The aim was to evaluate cytotoxicity effects of plants.Materials and methods: The ground plant material was exhaustively  extracted using methanol, acetone and water separately for 72 hrs. Theseorganic solvents were removed from filtrates using a rotavapour. Stock  solutions were prepared at 40 mg/ml Dimethyl sulfoxide (DMSO) and testsolutions were transferred into vials and 10 brine shrimps introduced in  each. The number of dead shrimps was counted to ascertain toxicity. Ten A. salina nauplii (larva) were transferred into each sample vial and filtered brine solution was added to make 5 ml. The nauplii were counted macroscopically in the stem of the pipette against a lighted background. A drop of dry yeast suspension was added as food to each vial. Probit  analysis was used to determine the concentration at which lethality to brine shrimp represents 50 % (LC50).Results: All the tested extracts showed that the concentration is directly proportional to death of brine shrimps. Fifty percent lethality (LC50) of thetested crude extract ranged between 4.1 and 4.6 µg/ml with methanol  extract of B. abyssinica being the lowest and T. acutiloba the highest.Conclusion: This study revealed that 100% of plant crude extracts screened for activity against Artemisia salina larvae showed strong cytotoxicitybelow 10 µg/ml and plant species with LC50 values < 1000 µg/ml may not make good paediatric remedies due to their inherent toxicity.Key words: Medicinal plants, traditional pediatrics, cytotoxicit

Edibility of Trachyandra ciliata (L.f.) Kunth- an underutilized vegetable from South African Western Cape coast: a review

The aim of Sustainable Development Goal 2 (SDG2) is to end hunger, improve food security and nutrition and promote sustainable crop production by 2050. However, climate change, increasing soil salinization and the inadequate availability of fresh water have negatively affected crop production around the world including South Africa, making it difficult to meet the required target. This necessitates the use of wild edible plants that are adapted to adverse conditions such as drought and salinity in order to mitigate this problem. The genus Trachyandra (Asphodelaceae) consist of three edible species (T. ciliata, T. divaricata and T. falcata) which are native to the dry saline environments of the western Cape coastal sand dunes. The genus is less studied with no record of cultivated species, although the existing literature states that T. ciliata, (wild cabbage) was originally used as a food source by the indigenous Khoi-san people who lived on the South African Cape coast. Colonization and removal of indigenous people from cultural lands led to erosion and detachment from the knowledge of the land and its useful plants. The species is used in selected restaurants where the inflorescence is steamed and eaten as a vegetable or added into a stew. This review explores the importance of Asphodelaceae family, T. ciliata as a vegetable crop and its potential as a pharmaceutical candidate. Furthermore, this review examines potential technological advances such as hydroponics that could be used for sustainable crop production of T. ciliata. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was utilized in the selection of articles in this review. The existing literature provided useful information on the potential of T. ciliata as a vegetable crop and the importance of using halophytes to achieve food security. This appraisal is expected to serve as a template for researchers, food enthusiasts, potential farmers and policy makers who may be keen in exploring further nutritional composition and medicinal potential of this plant

A survey of indigenous herbal diarrhoeal remedies of O.R. Tambo district, Eastern Cape Province, South Africa

Indigenous health system and the use of herbal plants have been recognized as pivotal in primary health care and a system to reckon with in achieving one of the targets of the millennial goals on health.An ethnobotanical survey was conducted to identify indigenous herbal remedies for diarrhoea and associated stomach ailments in rural areas of the O.R. Tambo district municipality in the Eastern Cape province of South Africa. The main objective of the study was to gather ethnomedical data onpotentially valuable indigenous medicinal plants for the eventual development of new pharmaceuticals and also emphasize the role of ethnomedicine in primary health care. The use of herbal remedies in thetreatment of diarrhoea and dysentery was investigated using interviews. The survey was conducted among traditional healers and knowledgeable local elders who use medicinal plants to treat common illnesses. Data from the survey indicated the names of plants commonly used in the treatment of diarrhoea and associated ailments, the methods of preparation, parts used and administration. A total of 32 plant species belonging to 26 families were reportedly used as diarrhoea remedy in the study area. The most predominant families of medicinal plants employed and most frequently recommended were Fabaceae (16.67%), followed by Hyacinthaceae and Hydnoraceae (8.33% each). The most commonly utilized portions of plants for medicinal purposes included roots and leaves. Other parts were corms, bulbs, tubers, fruits and bark. The methods of preparation often employed were decoctions and infusions whilst medication was frequently administered orally or as enema. Some of the plants were used singly or mixed with other plant(s) while some edible ones are consumed as food. The survey documented a diversity of plants employed as remedy for diarrhoea. Integration of this form of health care system into western medicine is warranted. The propagation of such medicinal plants is vital for sustainable use of these medicinal plants

THREATENED MEDICINAL PLANTS OF SOUTH AFRICA: CASE OF THE FAMILY HYACINTHACEAE

Background: Traditional medicine plays a major role in the primary health care of many people living in rural areas. South Africa is a home to over 30,000 species of higher plants and 3,000 of these species have been found to be used in traditional medicine across the country. South African medicinal plants are decreasing at an alarming rate as a result of over exploitation. Today many medicinal plants face extinction but detailed information is lacking. The purpose of this paper was to review current and proposed cultivation strategies that could be used to improve plant conservation statuses, livelihoods of the people involved in medicinal plant industry and sustainability of this industry. Methods: In this review, emphasis was on the members of Hyacinthaceae family and the species Siphonochilus aethiopicus (Schweinf) B.L. Burtt (Zingiberaceae), which are some of the most traded and used in traditional herbal medicine. Detailed literature search was conducted on the current strategies that are being used for the cultivation of medicinal and food crops and a conceptual analysis of how technologies used for the cultivation of non-medicinal crops could be adopted for cultivation of medicinal plants in Africa. Siphonochilus aethiopicus was used as a case study to demonstrate the potential of using alternative cultivation strategy such as hydroponics in the cultivation of medicinal plants. Results: The results showed that hydroponics has the potential to improve plant growth. In conclusion, evidences suggest that there is potential for growth in the medicinal plant industry if optimum cultivation technologies such as hydroponics are implemented despite the perception that Africans have an ingrained traditional preference of wild harvested plants, on the contrary many Africans have no issues with cultivated medicinal plants

Investigation of the antinociceptive and anti-inflammatory properties of Heteromorpha arborescens (Apiaceae)

Heteromorpha arborescens belongs to the family Apiaceae. It is commonly known as the parsley tree. One of its uses in the Eastern Cape Province of South Africa is for the treatment of abdominal pains. The therapeutic effects of the methanolic and aqueous root extracts of H. arborescens were investigated at two dose levels respectively on experimental models of pain and inflammation in rodents. The antinociceptive activity was evaluated using the hot-plate, abdominal constriction and formalin tests. The anti-inflammatory properties of these extracts were assessed using albumin and carrageenan as phlogistic agents. Both extracts produced significant (

The effect of Aloe ferox Mill. in the treatment of loperamide-induced constipation in Wistar rats

<p>Abstract</p> <p>Background</p> <p>Constipation is the most common gastrointestinal complaint all over the world and it is a risk factor of colorectal cancer. In this study, the efficacy of aqueous leaf extract of <it>Aloe </it><it>ferox </it>Mill. was studied against loperamide-induced constipation in Wistar rats.</p> <p>Methods</p> <p>Constipation was induced by oral administration of loperamide (3 mg/kg body weight) while the control rats received normal saline. The constipated rats were treated with 50, 100 and 200 mg/kg body weight/day of the extract for 7 days during which the feeding characteristics, body weight, fecal properties and gastrointestinal transit ratio were monitored.</p> <p>Results</p> <p>The extract improved intestinal motility, increased fecal volume and normalized body weight in the constipated rats, which are indications of laxative property of the herb with the 200 mg/kg body weight of the extract showing the best efficacy.</p> <p>Conclusion</p> <p>The effect of the extract compares favourably well with senokot, a standard laxative drug. These findings have therefore, lent scientific credence to the folkloric use of the herb as a laxative agent by the people of the Eastern Cape of South Africa.</p

Evaluation of the antibacterial and anticancer activities of some South African medicinal plants

<p>Abstract</p> <p>Background</p> <p>Several herbs are traditionally used in the treatment of a variety of ailments particularly in the rural areas of South Africa where herbal medicine is mainly the source of health care system. Many of these herbs have not been assessed for safety or toxicity to tissue or organs of the mammalian recipients.</p> <p>Methods</p> <p>This study evaluated the cytotoxicity of some medicinal plants used, inter alia, in the treatment of diarrhoea, and stomach disorders. Six selected medicinal plants were assessed for their antibacterial activities against ampicillin-resistant and kanamycin-resistant strains of <it>Escherichia coli </it>by the broth micro-dilution methods. The cytotoxicities of methanol extracts and fractions of the six selected plants were determined using a modified tetrazolium-based colorimetric assay (3-(4, 5-dimethylthiazol)-2, 5-diphenyl tetrazolium bromide (MTT) assay).</p> <p>Results</p> <p>The average minimum inhibitory concentration (MIC) values of the plants extracts ranged from 0.027 mg/mℓ to 2.5 mg/mℓ after 24 h of incubation. <it>Eucomis autumnalis </it>and <it>Cyathula uncinulata </it>had the most significant biological activity with the least MIC values. The in vitro cytotoxicity assay on human hepatocarcinoma cell line (Huh-7) revealed that the methanol extract of <it>E. autumnalis </it>had the strongest cytotoxicity with IC₅₀of 7.8 μg/mℓ. Ethyl acetate and butanol fractions of <it>C. uncinulata, Hypoxis latifolia, E. autumnalis </it>and <it>Lantana camara </it>had lower cytotoxic effects on the cancer cell lines tested with IC₅₀values ranging from 24.8 to 44.1 μg/mℓ; while all the fractions of <it>Aloe arborescens </it>and <it>A. striatula </it>had insignificant or no cytotoxic effects after 72 h of treatment.</p> <p>Conclusions</p> <p>Our results indicate that the methanol fraction of <it>E. autumnalis </it>had a profound cytotoxic effect even though it possessed very significant antibacterial activity. This puts a query on its safety and hence a call for caution in its usage, thus a product being natural is not tantamount to being entirely safe. However, the antibacterial activities and non-cytotoxic effects of <it>A. arborescens </it>and <it>A. striatula </it>validates their continuous usage in ethnomedicine.</p