Effects of cultivar and culture conditions on gamma-aminobutyric acid accumulation in germinated fava beans (Vicia faba L.).
BACKGROUND
High levels of gamma-aminobutyric acid (GABA) accumulate in plant tissues under various stresses. GABA accumulation is also influenced by cultivar. This aim of this study was to select the most promising cultivar of fava bean for GABA accumulation and to optimise the culture conditions for GABA production in germinated fava beans by response surface methodology based on central composite design (CCD).


RESULTS
GABA content and glutamate decarboxylase activity in germinated seeds of cultivar S2 were significantly higher than those in other cultivars (P < 0.05). A significant negative correlation (r = -0.765, P < 0.05) between germination percentage and 1000-kernel weight was observed. There was a linear relationship between GABA content and sprout length (R(2) = 0.816). The regression model fitted to the experimental data of CCD was valid in predicting GABA production in germinated fava beans. Temperature and pH value of the culture solution had significant effects on GABA content in germinated fava beans. Under optimal culture conditions (33.6 degrees C, pH 3.19 and an air flow rate of 1.19 L min(-1)), GABA content reached up to 2.41 g kg(-1) dry weight, about 48 times that in raw seeds.


CONCLUSIONS
Germinated fava bean is a good resource of GABA-rich food. Both cultivar and culture conditions have significant effects on GABA production.
Li
Yan
Y
College of Food Science and Technology, Nanjing Agricultural University, 210095 Nanjing, China.
Bai
Qingyun
Q
Jin
Xinjiang
X
Wen
Huanbin
H
Gu
Zhenxin
Z
D004777:Environment; D005838:Genotype; D018525:Germination / Q000502:physiology; D005968:Glutamate Decarboxylase / Q000235:genetics / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D016014:Linear Models; D036226:Seedlings / Q000235:genetics / Q000378:metabolism*; D012639:Seeds / Q000235:genetics / Q000378:metabolism*; D013696:Temperature; D031307:Vicia faba / Q000235:genetics / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000235:genetics / Q000378:metabolism*
D005680:gamma-Aminobutyric Acid; D005968:Glutamate Decarboxylase