US-Africa Collaboration in a Chemical Education Project Involving Analysis of Amaranthus Grain Oil from Selected Agro-Ecological Zones in Kenya

Abstract

Amaranthus is a cosmopolitan genus of annual and perennial plants. Worldwide, amaranths are cereals, leaf vegetables, or ornamental plants. Two African species of amaranthus grain; Amaranthus cruentus and Amaranthus hypochondriacus from selected regions in Kenya (Bondo, Bureti, Embu, Kenyatta University (KU), Kisumu, Kitale, Meru and Nyeri) were tested for oil content and fatty acid profiles. The oils from the grains were extracted using Soxhlet method for the total lipid content and Dyer and Bligh method for the fatty acid profile and oil oxidative stability. The fatty acid composition was determined using gas chromatography. The study showed that statistically there was no difference in the composition of oil among the various regions. The fatty acid profile for Amaranthus cruentus included: linoleic acid (35–38%), oleic acid (32–36%), palmitic acid (22–24%), stearic acid (2–4%), and linolenic acid (1–2%). There was no significant difference in the composition of fatty acids in the two species of amaranth studied except oleic and linoleic acids. The fatty acid profile for Amaranthus hypochondriacus was: linoleic (41–44%), oleic (26–34%), palmitic (19–24%), stearic (2– 3%), and linolenic acid (1–3%) with no significant differences in the selected regions. The present study reported capric, lauric, myristic, pentadecanoic, palmitoleic and heptadecanoic acids for the first time though in small amounts. The total lipid component ranged from 7 to 10% for Amaranthus hypochondriacus and 7 to 9% for Amaranthus cruentus. The results of the study compared well with those done earlier in other countries.