highly significantP < 0.0001
The results showed highly significant (( P < 0.0001) linear correlations ( r = 0.9784–0.9907) between the Trp values determined by GC and HPLC for both the low-normal and normal-high ranges (data not shown) and between the Trp values determined by GC and the standard fluorimetric method ( r = 0.9774) (Fig. 2 ).