# Effect of Processing Methods on Amino Acid and Fatty Acid Composition of _Parkia biglobosa_ Seeds
## 4 Discussion  
Food processing has an important role in achieving nutrition and food security [15]. The nutritional qualities of plant proteins are based on their amino acid and fatty acid composition [25]. In this study, the protein isolates from _Parkia biglobosa_ exhibited a wider spectrum of the highest amino acid content when compared with the fermented and defatted samples (Table 1). The processing of food products has been demonstrated to improve their functional properties and nutritive values [26]. Our findings revealed that glutamic acid and aspartic acid are the most abundant amino acids in the PI sample. This finding is in accordance with that reported by [PERSON] et al. [27] on black turtle beans, in which the legume contains a high level of glutamic and aspartic acids. Similarly, protein isolated from red kidney beans has been reported to contain a high level of glutamic acid and aspartic acid [28,29]. Glutamic acid plays a key role in cellular metabolism and brain function [30,31]. Glutamic acid is also a precursor of gamma-aminobutyric acid (GABA), which is found in abundance in the pancreas and cerebellum. During neurological syndromes, such as stiff-man syndrome, there is a decrease in the synthesis of GABA, triggering an autoimmune destruction of the pancreas that results in diabetes mellitus in the patient [32]. The detoxification and cardioprotective potential of glutamic acid have also been reported in plant seeds [33]. Aspartic acid also plays a major role in brain function, gluconeogenesis, and the stimulation of growth hormones [34]. The PI samples could, therefore, be used to ameliorate mental retardation, cardiovascular diseases, and other diabetic complications. Protein isolate samples from grains such as corn and wheat are reported to be lower in lysine. Lysine improves body mass and lowers anxiety, glucose, and osteoporosis [35]. The lysine value for the PI sample was observed to be within the range of the egg reference protein (6.3 g/100 g) [36]. The value (3.31-3.69 g/100 g) of lysine in the PI sample was better when compared to the value (5.36-8.44 mg/g) previously reported in respect of the _Moringa oleifera_ tree [37]. This implies that the sample could serve as a good source of cereal fortification in weaning foods. Lucine has been reported to enhance protein synthesis, which plays a vital role in muscle building [38]. The value of leucine in the PI sample (8.30 g/10 g) was similar to pigeon peas (8.40 g/100 g) and higher when compared with Africa yarn beans (7.45 g/100 g) (Table 3) [39]. Histidine plays an important role in child growth, while arginine has been reported to increase insulin sensitivity and vasodilation of coronary arteries [40,41]. Arginine and histidine values in the PI sample (Table 4) were observed to be higher than the recommended values for preschool children (2-5 years old) and adults [36]. Therefore, the sample could serve as a remedy for metabolic complications in child growth. Cystine values were observed to be the least concentrated amino acids in all the samples. This supports the previous report that cystine is the limiting amino acid in legumes [42]. The nutritive value of the protein source depends on its essential amino acid composition and ability to meet nitrogen demand [43]. The values of the percentage total essentialamino acid (TEAA) with histidine for the PI sample (Table 2) were similar to some non-convectional animal sources, such as _Achatina achatina_, _Achatina marginata_, and _Phaseolus vulgaris_ L. [43; 44]. The PI % TEAA value is within the recommended standard for infants (26%) and adults (11%) [20]. The high content of essential amino acids in the PI sample implies that they could be used in the complementary treatment of protein malnutrition. Aromatic amino acids are the precursors of thyroxine and epinephrine, which are important in many biological functions [20]. The TArAA values of the PI sample are within the recommended ranges (6.8\(-\)11.8 g) for infant protein [25].