Phytosterol and amino acid profiles of palm kernel oil: possible metabolic implications

Amino Acid Profiles, Total Nitrogen Contents, and Computed-Protein Efficiency Ratios of Manihot esculenta Root and Dioscorea rotundata Tuber Peels

“…However, the vagaries of intermediary metabolism, especially in tuberous roots during storage or sprouting, may prompt wide variability in their amino acids concentrations and distribution [42]. Since the peels contained all the essential amino acids, their amino acids contents can be used to synthesize proteins with strikingly different properties and activities unlike those of palm kernel oil which did not contain essential amino acids like Ile, Thr, and Val [35]. The corrections for the sulphur-containing amino acids in the peels were calculated to be 1/0.31 or 3.23 times and 1/0.22 or 4.55 times the protein contents of cassava and yam peels, respectively.…”

“…Therefore, the findings of the present study did not qualify proteins from cassava and yam peels to be of good quality by virtue of their C-PER indices. Nonetheless, cassava and yam peels were better protein sources than palm kernel oil [35,59]. However, the use of cassava or yam peels as livestock feeds are usually supplemented with other sources that are rich in good quality proteins or are subjected to biofortification and protein enrichment as previously described [12,26,32,46,[60][61][62].…”

“…Amino acid analysis was carried out using ion-exchange chromatography (IEC) as described by Spackman et al [33], Ibegbulem et al [34], and Ibegbulem and Belonwu [35]. The samples were defatted, acid digested before dispensing the digest into the amino acid analyzer.…”

“…Total glucogenic amino acid (TGAA) was calculated by summing up the concentrations of Arg, Gln, His, Pro, Met, Thr, Val, Asp, Asn, Ala, Cys, Gly, and Ser while the total ketogenic amino acids (TKAA) were calculated by summing up the Lys and Leu contents of the samples. Trp was not used in the computations because it is normally destroyed during such chemical analysis [4,34,35].…”

“…Acids. The essential amino acid (EAA) score of an EAA was calculated as the ratio of the concentration of that EAA (mg/g protein) to that of its desired concentration (mg/g protein) in a reference food protein [34,35,40]. The FAO/WHO/UNU [38] amino acid scores were used as standard reference values.…”