Effect of Growth on the Levels of Free Histidine and Amino Acids in White Muscle of Milkfish (Chanos chanos)

Abstract

Accumulation patterns of free amino acids (FAAs) in white muscle of milkfish (Chanos chanos) during the period of 8-month growth were investigated. Histidine, taurine, and glycine were the predominant FAAs. An increase in histidine was observed during growth. The level present in the 1-month-reared fish (mean weight = 58 g) was about 5 times higher than that in the initial fish (1.4 g). After 8 months of growth, milkfish contained 59 μmol/g, which was responsible for 72% of the total FAAs. There was a positive correlation between the histidine content and fish body weight. In contrast, taurine decreased with increasing rearing time. The glycine level was not correlated well with fish size. The total relative amounts of histidine, taurine, and glycine remained about the same, although the individual contributions varied considerably in the FAA pool during the period of cultivation. Keywords: Milkfish; free amino acids; histidine; growth; white muscle