Throughout evolution, plants have developed the ability to produce secondary phenolic metabolites, which are important for their interactions with the environment, reproductive strategies and defense mechanisms. These (poly)phenolic compounds are a heterogeneous group of natural antioxidants found in vegetables, cereals and leguminous that exert beneficial and protective actions on human health, playing roles such as enzymatic reaction inhibitors and cofactors, toxic chemicals scavengers and biochemical reaction substrates, increasing the absorption of essential nutrients and selectively inhibiting deleterious intestinal bacteria. Polyphenols present in some commodity grains, such as soy and cocoa beans, as well as in other vegetables considered security foods for developing countries, including cassava, taro and beetroot, all of them cropped in Brazil, have been identified and quantified in order to point out their bioavailability and the adequate dietary intake to promote health. The effects of the flavonoid and non-flavonoid compounds present in these vegetables, their metabolism and their effects on preventing chronic and degenerative disorders like cancers, diabetes, osteoporosis, cardiovascular and neurological diseases are herein discussed based on recent epidemiological studies.

https://www.mdpi.com/2072-6643/9/9/1044/pdf

Polyphenols from Root, Tubercles and Grains Cropped in Brazil: Chemical and Nutritional Characterization and Their Effects on Human Health and Diseases.

Potential raw materials for biorefineries to ensure food security: The Cocoyam case

Strategy for the selection of the minimum processing scale for the economic feasibility of biorefineries

Intercropping as an effective component of integrated weed management in tropical root and tuber crops: A review

Retrotransposon-based molecular markers were applied for the first time within the genera Xanthosoma and Colocasia to assess intraspecific variability among 27 accessions of cocoyam (Xanthosoma sagittifolium) and taro (Colocasia esulenta). Retrotransposons were isolated and sequenced; long terminal repeat (LTR) primers were designed to obtain inter-retrotransposon amplified polymorphism (IRAP) fingerprints. A set of six chosen LTR primers yielded 433 reproducible bands across 20 X. sagittifolium samples. Out of the 433 bands, 400 fragments (92 %) were polymorphic. In seven C. esculenta accessions, the six primers amplified a total of 354 reproducible, informative data points, of which 285 (80.5 %) were polymorphic. Cluster analysis placed all the accessions in two groups according to their species. The accessions of X. sagittifolium were further divided into two subgroups corresponding to their ploidy level. Moreover, the genetic variability accessed by IRAP markers allowed separation of X. sagittifolium and C. esculenta accessions according to their type and botanical variety respectively. The results suggest that retrotransposon activity continued after Xanthosoma speciation. The data and approach provides a basis for better germplasm management, future systematic studies and genetic improvement, as well as for exploration of the role of retrotransposons in cocoyam and taro polyploid formation and genome dynamics.

/pdf/retrotransposon-molecular-markers-resolve-cocoyam-xanthosoma-3mdigmf9kl.pdf

Retrotransposon molecular markers resolve cocoyam (Xanthosoma sagittifolium) and taro (Colocasia esculenta) by type and variety

Cocoyams (old-taro: Colocasia esculenta; newtannia: Xanthosoma sagittifolium) yield corms as root crops produced in regions of tropical and subtropical developing countries. In certain countries such as Ghana, there are surpluses in production but deficits in cereals. Cocoyams are used in a range of indigenous foods. Post harvest losses are high due to mechanical damage of corms during harvest and microbial attacks on such damaged corms during storage. Cocoyams contain, on average, 25% starch (wet weight basis) with A-type structures characterized by small granule size (<1.5 μm). Non-starch polysaccharides in cocoyams confer gummy properties to the starch. However, mechanical effects of raphides—crystals of calcium oxalate and other components—produce irritation when raw corm tissue is ingested resulting in several levels of discomfort. With appropriate processing, cocoyams could be a rich source of starch for food and industrial applications and corms have potential for new product development. Stabilizing cocoyam crops and adding value could greatly improve its utilization in cocoyam producing countries.

/pdf/cocoyam-corms-and-cormels-an-underexploited-food-and-feed-479blp0lhg.pdf

Emmanuel L. Omenyo

Papers

Cocoyam (corms and cormels)—An underexploited food and feed resource