Analysis Of L- Citrulline, L-Arginine And L-Glutamic Acid In Selected Fruits, Vegetables, Seeds And Nuts Sold In Nairobi City County, Kenya

ABSTRACT

L-citrulline, L-arginine and L-glutamic acid are some of the amino acids which are vital in the human body. L-citrulline boosts immunity, combats sarcopenia, detoxifies the liver and enhances male fertility. L-arginine boosts internal production of nitric oxide thus enhancing dilation of blood vessels, inhibits aging process, prevents abnormal blood clotting and accelerates healing of wounds. L-glutamic acid cleanses the central nervous system and improves overall brain health, attitude and mental performance. However, only young and healthy people endogenously generate enough of these vital amino acids while premature babies and old people do not generate enough of the amino acids. Oral supplements are very expensive and have side effects such as; headache, vision impairment, flushing, heart attack and stroke. There is therefore the need for safe alternative and cheaper sources of these amino acids. Fruits, vegetables, seeds and nuts can be good sources of L-citrulline, L-arginine and L-glutamic acid. However, there is scarce data on the levels of these amino acids in the locally grown farm produce. The objective of this study was to determine the levels of L-citrulline, L-arginine and L-glutamic acid in selected fruits, vegetables, nuts and seeds sold in selected markets in Nairobi city County, Kenya. Thin Layer Chromatography (TLC) was used for identification and Liquid Chromatography-Mass Spectrometer (LC-MS) for quantification of the amino acids. The data was analyzed using one-way ANOVA. TLC profiles showed presence of both L-arginine and L-citrulline in most fruits, vegetables and nuts while L-glutamic acid was present in the seeds. The levels of the amino acids in the fruits and vegetables ranged as follows: L-citrulline ranged, 0.65-19.41 mg/100g in the button mushroom, cucumber, pumpkin, amaranthus, kales, 3.16-3.79 mg/100g in the watermelons and 1.57-10.21mg/100g in the macadamia nuts, pea nuts and cashew nuts. L-arginine was in the range; 1.73-16.48 mg/100g in the amaranthus, kales, button mushroom, butternut squash and cucumber, 5.44-6.56mg/100g in the fruits and 0.93-10.73mg/100g in the nuts and L-glutamic acid, 0.013-0.28 mg/100g in the seeds of ; pumpkin, butternut and watermelons. The results showed that locally available vegetables, fruits and nuts contain significant levels of L-citrulline and L-arginine, whereas seeds contain significant levels of L-glutamic acid. The information obtained from this study is vital to the ministry of health and nutritionists towards measures on improving the quality of life by encouraging dietary supplementation of the amino acids through consumption of locally available farm produce. The research findings will contribute to knowledge on presence of the amino acids in fruits, vegetables and nuts grown in Kenya.