Composition of marama bean protein

Are South African Wild Foods the Answer to Rising Rates of Cardiovascular Disease?

The rising burden of cardiovascular disease in South Africa gives impetus to managerial changes, particularly to the available foods in the market. Since there are many economically disadvantaged groups in urban societies who are at the forefront of the CVD burden, initiatives to make healthier foods available should focus on affordability in conjunction with improved phytochemical diversity to incentivize change. The modern obesogenic diet is deficient in phytochemicals that are protective against the metabolic products of sugar metabolism, i.e., inflammation, reactive oxygen species and mitochondrial fatigue, whereas traditional southern African food species have high phytochemical diversity and are also higher in soluble dietary fibres that modulate the release of sugars from starches, nurture the microbiome and produce digestive artefacts that are prophylactic against cardiovascular disease. The examples of indigenous southern African food species with high horticultural potential that can be harvested sustainably to feed a large market of consumers include: Aloe marlothii, Acanthosicyos horridus, Adansonia digitata, Aloe ferox, Amaranthus hybridus, Annesorhiza nuda, Aponogeton distachyos, Bulbine frutescens, Carpobrotus edulis, Citrullus lanatus, Dioscorea bulbifera, Dovyalis caffra, Eleusine coracana, Lagenaria siceraria, Mentha longifolia, Momordica balsamina, Pelargonium crispum, Pelargonium sidoides, Pennisetum glaucum, Plectranthus esculentus, Schinziophyton rautanenii, Sclerocarya birrea, Solenostemon rotundifolius, Talinum caffrum, Tylosema esculentum, Vigna unguiculata and Vigna subterranea. The current review explains the importance of phytochemical diversity in the human diet, it gives a lucid explanation of phytochemical groups and links the phytochemical profiles of these indigenous southern African foods to their protective effects against cardiovascular disease.

Caecal microbial communities, functional diversity, and metabolic pathways in Ross 308 broiler chickens fed with diets containing different levels of Marama (Tylosema esculentum) bean meal

The caecum of a chicken harbors complex microbial communities that play vital roles in feed digestion, nutrient absorption, and bird health. Understanding the caecal microbial communities could help improve feed utilization efficiency and chicken product quality and, ultimately, deliver sustainable poultry production systems. Thus, this study assessed the caecal microbial communities and their functional diversity and metabolic pathways in broilers reared on diets containing different levels of marama (Tylosema esculentum) bean meal (MBM). A total of 350, day-old male Ross 308 broiler chicks were randomly allocated to five dietary treatments formulated as follows: a soybean-based standard broiler diet (Con_BC); Con_BC in which soybean products were substituted with 7 (M7_BC), 14 (M14_BC), 21 (M21_BC), and 28% (M28_BC) MBM. The dietary treatments were distributed to 35 replicate pens (10 birds each). After 42 days of feeding, the birds were slaughtered and thereafter caecal samples were collected from each replicate pen. Subsequently, the samples were pooled per treatment group for metagenomics sequence analysis. The results revealed that the bacteria domain (99.11%), with Bacteroides, Firmicutes and Proteobacteria being the most prominent phyla (48.28, 47.52, and 4.86%, respectively). Out of 846 genera obtained, the most abundant genera were Bacteroides, Clostridium, Alistipes, Faecalibacterium, Ruminococcus, Eubacterium, and Parabacterioides. At the genus level, the alpha-diversity showed significant (p < 0.05) difference across all treatment groups. Based on the SEED subsystem, 28 functional categories that include carbohydrates (14.65%), clustering-based subsystems (13.01%), protein metabolism (10.12%) were obtained. The KO analysis revealed 183 endogenous pathways, with 100 functional pathways associated with the metabolism category. Moreover, 15 pathways associated with carbohydrates were observed. The glycolysis/gluconeogenesis, galactose metabolism, pyruvate metabolism (15.32, 12.63, and 11.93%) were the most abundant pathways. Moreover, glycoside hydrolases (GH1, GH5, and GH13) were the most prominent carbohydrates-active enzymes. Therefore, results presented in this study suggest that dietary MB meal can improve microbial communities and their functional and metabolic pathways, which may help increase poultry production.

Influence of extraction pH on the foaming, emulsification, oil-binding and visco-elastic properties of marama protein

BACKGROUND

Marama bean protein, as extracted previously at pH 8, forms a viscous, adhesive and extensible dough. To obtain a protein isolate with optimum functional properties, protein extraction under slightly acidic conditions (pH 6) was investigated.

RESULTS

Two-dimensional electrophoresis showed that pH 6 extracted marama protein lacked some basic 11S legumin polypeptides, present in pH 8 extracted protein. However, it additionally contained acidic high molecular weight polypeptides (∼180 kDa), which were disulfide crosslinked into larger proteins. pH 6 extracted marama proteins had similar emulsification properties to soy protein isolate and several times higher foaming capacity than pH 8 extracted protein, egg white and soy protein isolate. pH 6 extracted protein dough was more elastic than pH 8 extracted protein, approaching the elasticity of wheat gluten.

CONCLUSION

Marama protein extracted at pH 6 has excellent food-type functional properties, probably because it lacks some 11S polypeptides but has additional high molecular weight proteins. © 2017 Society of Chemical Industry.