Application of a picrate semi-quantitative screening assay for the cyanogenic potential of cassava roots at a remote field site

• Published in: Journal of the science of food and agriculture 2000-04, Vol.80 (5), p.590-594
• Main Authors: Wilson, Warren M, O'Brien, Gerard M, Dufour, Darna L
• Format: Article
• Language: English
• Subjects: Amazon; assay; Biological and medical sciences; cassava; cyanide; cyanogenic potential; Food industries; Fruit and vegetable industries; Fundamental and applied biological sciences. Psychology; picrate; rural; semi-quantitative
• ISSN: 0022-5142; 1097-0010
• DOI: 10.1002/(SICI)1097-0010(200004)80:5<590::AID-JSFA577>3.0.CO;2-J

The purpose of this research was to test the accuracy of the picrate screening assay (PSA) in the evaluation of the cyanogenic potential of cassava roots at a remote field site under conditions of unusual difficulty. To do this, a PSA was conducted in the field and compared to data collected previously on five of the same cassava varieties using the Cooke colorimetric enzymic assay. PSA data were collected for 10 different cassava varieties in the Tukanoan Indian village of Yapú in the Colombian Amazon region. The PSA results agree with Tukanoan classifications of cassava; that is, those classified as ‘sweet’ by the Tukanoans generally had low‐to‐moderate parenchymal cyanogenic potential (0–50 mg kg−1 fwb of HCN), while those that they classify as ‘bitter’ had high parenchymal cyanogenic potential (≥100 mg kg−1 fwb of HCN). The PSA results also agree with the data collected using the Cooke colorimetric enzymic assay. The data suggest that the PSA is an appropriate test of the cyanogenic potential of cassava roots in remote field sites. © 2000 Society of Chemical Industry