Asemota, Helen N.; Omoruyi, Felix O.; McAnuff, Marie; Dilworth, Lowell L.; McFarlane-Anderson, Norma; Morrison, Errol Y.; Harding, Wayne W.; Jacobs, Helen M.; Ahmad, Mohammed H.
Author Affiliation, Ana.
Department of Basic Medical Sciences
Analyses of natural products in Jamaican tuber crops: The need for biotechnological exploitation
Jamaican journal of science and technology
Date of Publication
Ten varieties of Jamaican tuber crops namely: Dioscorea polygonoides cultivar (cv.) Bitter yam, Dioscorea alata cvs. St. Vincent, Renta, Moonshine and Sweet Yam; Dioscorea cayenensis cv. Round leaf yellow yam; Himber (Rajania cordata), Cocoyam (Xanthosoma sp), Dasheen (Colocasia esculenta) and sweet potato (Ipomoea batatas) were screened for five important natural product contents. Bitter yam and round leaf yellow yam contain appreciable levels of the 'phytoestrogen' sapogenin and ascorbic acid (vitamin C). The main sapogenin found in bitter yam and round leaf yellow yam is diosgenin and it was highest in bitter yam (4.092 ± 1.800 mg/g dry weight), followed by round leaf yellow yam (0.135 ± 0.045 mg/g dry weight) while the other varieties, sweet yam, moonshine, renta and himber showed traces of sapogenin (< 0.06 mg/g dry weight). The level of ascorbic acid in round leaf yellow yam was highest (0.84 ± 0.13 mg/g dry weight) followed by dasheen (0.38 ± 0.05 mg/g dry weight) and cocoyam (0.35 ± 0.04 mg/g dry weight). Trypsin inhibitor activity was highest in yellow yam (207.80 ± 43.3 TIU/g dry weight) and lowest in sweet potato (173.90 ± 15.39 TIU/g dry weight). The phytic acid content was highest for sweet potato (7.46 ± 0.51 mg/g dry weight) and lowest for Irish potato (3.42 ± 0.03 mg/g dry weight). Total phenol was in St. Vincent (7.93 ± 0.61 mg/g dry weight) while the other varieties contained less than 0.9 mg/g dry weight. These tuber crops, namely: Bitter yam, Round leaf yellow yam, St. Vincent and Sweet potato could therefore be exploited for their natural product contents.....