No abstract

Moringa is a multipurpose tree and an important vegetable crop elsewhere. However, it is recently introduced to Botswana and grown in the backyards of households as a shade. Its uses are generally unknown to the community, and it is underutilized despite its huge nutritional and non-food uses. In this study, the nutritional composition, bioactive components and antioxidant activity of Moringa stenopetala (MS) and Moringa oleifera (MO) leaves grown in Gaborone Botswana were determined. Except for moisture content, no significant difference (p > 0.05) was observed in proximate composition between MS and MO leaves. The moisture content of MS leaves was significantly (p < 0.05) higher than that of MO leaves. MS leaves had significantly (p < 0.05) higher Na and K contents than MO leaves. However, MO leaves had significantly (p < 0.05) higher Zn content than MS leaves. The two Moringa leaves had comparable Fe, Ca and Mg contents. The Vitamin C content of MO leaves was significantly (p < 0.05) higher than that of MS leaves. However, MS leaves had significantly (p < 0.05) higher total phenolic, total flavonoid contents (mg/100 g) and antioxidant activity (µg/mL) as compared to MO leaves. The Moringa leaves can be used for development of functional foods with improved nutrition and health benefits. Graphical Abstract

Cereal Chem. 86(5):575-581Proteolysis during cereal germination is vital both to seedling growth and the success of commercial malting and brewing. In this study, proteinases in proteolytic extracts from seeds and germinated grains of 11 Botswana sorghum cultivars were analyzed and partially characterized by one-dimensional electrophoresis on SDS-PAGE gels containing incorporated gelatin. Proteinase polymorphism was detected in both germinated and ungerminated sorghum grains. Fifteen distinct proteinase bands, with M r valuesof 27,000-100,000 were detected in sorghum malt extract, while ungerminated sorghum displayed a maximum of four bands (M r ≈ 78,000-100,000). Band numbers and identity varied markedly according to cultivar. More proteinase bands were detected at pH 4.6, than at pH 6.2 and 7.0, suggesting pH optima considerably below neutrality. Cysteineproteinases constituted a higher proportion (9 of 15) of the detected sorghum malt proteinases and were most detectable at pH 4.6. Multiple representatives were also detected for both serine-and metallo-proteinases, although these were more active at pH 6.2 and 7.0. 1-10 Phenanthroline inhibited malt metallo-proteinase more strongly than EDTA, suggesting that these enzymes were most probably zinc-dependent. Aspartyl-proteinases were not detected, probably because of the substrate employed. Results indicate that the sorghum proteinase system is complex.

The consumption of traditional and indigenous foods and beverages varies across different ethnic communities and is often influenced by geographical location. However, the diversity of edible plants is rapidly declining due to climate change, leading to a loss of knowledge about useful plants used by different communities before the plant itself becomes extinct. This research investigated the edible plant types and investigated the processing steps of plant-based traditional foods/dishes and beverages of Gumare village, located in the catchment area of the Okavango Delta in the northwest of Botswana. Questionnaire interviews and focus group discussions (FGD) were used to collect data. The study identified 52 wild and 19 domesticated edible plants used in the preparation of traditional foods/dishes and beverages of Gumare village. Maize, sorghum, millets, beans, melon, watermelon, pumpkin, bottle gourd and sweet potato are widely used domesticated crops. The wild edible plants are either directly used after minor processing or as recipes in traditional dishes and/or as an inoculum in the fermentation, as a substrate in traditional beverages and some as medicinal plants. However, some taboos and food safety challenges were observed in the use of certain plants. The study highlighted a decline in the use of traditional foods/dishes and beverages, particularly among the young generation. The youth indicated that they have a low interest in gathering traditional foods and beverages due to the time-consuming nature during harvesting and the labour-intensive processing. In addition, they indicated the dangers of attacks by wild animals from veld by reptiles (for example snakes and pythons) and alligators (crocodiles) from rivers during the harvesting of raw materials used in traditional foods and dishes. For the communities, the diverse edible wild plants documented are a source of nutrients and bioactive compounds such as dietary fibers, phenolics, terpenes, essential oils, carotenoids, and alkaloids that help to combat malnutrition and for use as traditional medicines to support health and wellness. In conclusion, the significant diversity of wild edible plants and domesticated crops in Gumare village, likely due to its location in the catchment area of the Okavango Delta, plays a crucial role in diet diversification and can contribute to food and nutrition security. However, for most wild edible plants of Botswana, information on their nutrient and bioactive compounds are still limited. This study provides baseline information for further chemical investigation and development of resources in the formulation of functional foods and nutraceuticals. Graphical Abstract