In contrast,
the highest yields were obtained from leaves (106.21 ± 0.63 mg
GA g−1) but extraction rate was not affected by temperature.
Hence the major phenolic fraction in leaves appears to be soluble
in water at temperatures ≤ 40 ◦C. Alternatively, it is possible
that thermal degradation occurs at temperatures > 40 ◦C as
some phenolic compounds are heat-labile.