Chemical composition and microflora of black cumin (Nigella sativa L.) seeds growing in Saudi Arabia

Abstract

Proximate analysis of black cumin seeds showed a composition of 20.85% protein, 38.20% fat, 4.64% moisture, 4.37% ash, 7.94% crude fibre and 31.94% total carbohydrates. Potassium, phosphorus, sodium and iron were the predominant elements present. Zinc, calcium, magnesium, manganese and copper were found at lower levels. However, lead, cadmium and arsenic were not detected in the seeds. Linoleic and oleic acids were the major unsaturated fatty acids while palmitic acid was the main saturated one. Glutamic acid, arginine and aspartic acid were the main amino acids present while cystine and methionine were the minor amino acids. These results indicate the high nutritional potential of Saudi black cumin seeds especially as a source of protein and fat. The total aerobic bacterial count was 7 × 107 cfu/g and the yeast and mould counts were 4 × 102 cfu/g. The low numbers observed for Staphylococcus aureus and Bacillus cereus make black cumin seeds acceptable, without any associated health hazard. © 1992.