Effects of cultivar and culture conditions on γ‐aminobutyric acid accumulation in germinated fava beans (Vicia faba L.)

BACKGROUND: High levels of γ‐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 (R² = 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 °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. CONCLUSION: Germinated fava bean is a good resource of GABA‐rich food. Both cultivar and culture conditions have significant effects on GABA production. Copyright © 2009 Society of Chemical Industry     

Accumulation of γ-aminobutyric acid in germinated soybean (<Emphasis Type="Italic">Glycine max</Emphasis> L.) in relation to glutamate decarboxylase and diamine oxidase activity induced by additives under hypoxia

High levels of γ-aminobutyric acid (GABA) accumulate in plant tissues under various stresses and exogenous additives. The purpose of this research is to provide an effective finding that can prove a rapid accumulation of GABA in germinated soybean (Glycine max L.) in response to different additives under hypoxia. Hypoxia-induced GABA accumulation in soybean embryo resulted in part from polyamine oxidation. Response to different concentration of glutamate (Glu), pyridoxal phosphate, arginine, CuCl₂, NaCl, and CaCl₂, a significant difference including GABA accumulation, changes of Glutamate decarboxylase (GAD), and Diamine oxidase activity (DAO) activity in germinated soybean under hypoxia occurred (p < 0.05) and the maximum accumulation of GABA were 4.07, 3.02, 3.50, 3.26, 4.00, and 3.30 g kg⁻¹ DW respectively, which were significantly higher than those germinated soybean under normal culture (CK) and hypoxia culture (CK₀) (p < 0.05). The GAD and DAO have different distributions in cotyledon and embryo of germinated soybean, and the enzyme activity mainly located in embryo of germinated soybean. Germinated soybean is a good resource of GABA-rich food. Different additives have significant effects on GABA production, among which Glu and NaCl are ideal material for GABA accumulation.     

Microarray studies on the genes responsive to the addition of spermidine or spermine to a Saccharomyces cerevisiae spermidine synthase mutant

The naturally occurring polyamines putrescine, spermidine or spermine are ubiquitous in all cells. Although polyamines have prominent regulatory roles in cell division and growth, precise molecular and cellular functions are not well‐established in vivo. In this work we have performed microarray experiments with a spermidine synthase, spermine oxidase mutant (Δspe3 Δfms1) strain to investigate the responsiveness of yeast genes to supplementation with spermidine or spermine. Expression analysis identified genes responsive to the addition of either excess spermidine (10^?5 M ) or spermine (10^?5 M ) compared to a control culture containing 10^?8 M spermidine. 247 genes were upregulated > two‐fold and 11 genes were upregulated >10‐fold after spermidine addition. Functional categorization of the genes showed induction of transport‐related genes and genes involved in methionine, arginine, lysine, NAD and biotin biosynthesis. 268 genes were downregulated more than two‐fold, and six genes were downregulated > eight‐fold after spermidine addition. A majority of the downregulated genes are involved in nucleic acid metabolism and various stress responses. In contrast, only a few genes (18) were significantly responsive to spermine. Thus, results from global gene expression profiling demonstrate a more major role for spermidine in modulating gene expression in yeast than spermine. Copyright © 2009 John Wiley & Sons, Ltd.     

GABA shunt and polyamine degradation pathway on γ-aminobutyric acid accumulation in germinating fava bean (Vicia faba L.) under hypoxia

GABA shunt and polyamine degradation pathway on γ-aminobutyric acid (GABA) accumulation in germinating fava bean under hypoxia was investigated. GABA content, GAD and DAO activity were significantly increased under hypoxia treatment. Glu and polyamine contents enhanced largely and thus supplied as sufficient substrates for GABA formation. In contrast, GABA content decreased, mainly in the embryo, after removing the hypoxia stress. DAO activity, Glu and polyamines contents decreased, while an increment of GAD activity was observed. This indicated that GAD activity can be not only regulated by hypoxia, but by the rapid growth of embryo after the recovery from hypoxia stress. When treated with AG, DAO activity was almost inhibited completely, and the GABA content decreased by 32.96% and 32.07% after treated for 3 and 5 days, respectively. Hence, it can be inferred that about 30% of GABA formed in germinating fava bean under hypoxia was supplied by polyamine degradation pathway.     

Determination of biogenic amines with an electrochemical biosensor and its application to salted anchovies

This paper describes the assembling and optimization of an electrochemical biosensor for the determination of biogenic amines (putrescine, cadaverine, histamine, tyramine, spermidine, spermine, tryptamine) commonly present in food products, and its application to salted anchovy samples. Variations of the amine content in anchovies during ripening time were measured both with the biosensor and ion chromatography with integrated pulsed amperometric detection (IC-IPAD). The probe is based on a platinum electrode which senses the hydrogen peroxide produced by the reaction catalysed by the enzyme diamine oxidase (DAO), purified from commercial seeds of cicer and immobilized on the electrode surface. Parameters such as enzyme immobilization and pH have been studied and optimised in order to obtain similar sensitivity for all the amines tested. The immobilization of the enzyme on a nylon-net membrane, using glutaraldehyde as cross-linking agent, and phosphate buffer at pH 8.0 were selected. The detection limit was 5 × 10⁻⁷ mol litre⁻¹. The linear range common to the amines tested was observed from 1 × 10⁻⁶ to 5 × 10⁻⁵ mol litre⁻¹. The effect of potentially interfering compounds was also evaluated. Underivatized biogenic amines such as putrescine, cadaverine, histamine, tyramine and spermidine were also detected with the IC-IPAD method. Changes in the concentration of biogenic amine content in salted anchovy samples, measured with the biosensor and IC-IPAD methods, exhibited the same trend and demonstrated that the biosensor is a useful tool to monitor the variation of the total amine content in fish during storage.     

Optimal soaking conditions and addition of exogenous substances improve accumulation of γ-aminobutyric acid (GABA) in germinated mung bean (Vigna radiata)

Germinated mung beans have been widely used as fresh vegetable or processed healthy food due to their high amounts of bioactive and nutritional compounds, including γ-aminobutyric acid (GABA). The objectives of this study were to investigate the effects of different soaking conditions (temperature, ratios of seeds to water, soaking time, pH, addition of L-glutamic acid (L-Glu) or gibberellic acid (GA3)) and germination time on accumulation of GABA in the germinated mung bean seeds. The mung bean seeds, soaked at 40°C for 4 h with ratio of seeds to water of 1:4 (g mL⁻¹) and then germinated for 7 h, accumulated higher amount of GABA than other soaking conditions and germination time. The addition of GA3 (0.30 mg L⁻¹) or L-glu (1,000 mg L⁻¹) or acidifying to pH 5.5 of the soaking water had high impact on the GABA accumulation. Among them, the soaking water with pH 5.5 was more effective than adding with the L-Glu or GA3 in the production of GABA (1677 mg/kg powder) and essential amino acids (16.56 g/100g powder) in the germinated mung bean seeds. The findings of this study provide useful information to produce GABA-enriched and healthy foods from mung beans.     

Purification and characterisation of β‐mannanase from Lactobacillus plantarum (M24) and its applications in some fruit juices

β‐Mannanase was purified 2619.05‐fold from the Lactobacillus plantarum (M24) bacterium by ammonium sulphate precipitation and ion exchange chromatography (DEAE‐Sephadex). The purified enzyme gave two protein bands at a level of approximately 36.4 and 55.3 kDa in the SDS‐PAGE. The purified mannanase enzyme has shown its maximum activity at 50 °C and pH 8, and it has been also determined that the enzyme was stable at 5–11 pH range and over 50 °C. The V_max and K_m values have been identified as 82 mg mannan mL^?1 and 0.178 mm , respectively. The effects of some metal ions such as Fe²⁺, Ca²⁺, Co²⁺, Ni²⁺, Mn²⁺, Cu²⁺ and Zn²⁺ on the mannanase enzyme have been also investigated, and it has been determined that all metal ions had significant effects on the activation of the mannanase enzyme. In addition, the effectiveness of the purified mannanase enzyme on the clarification of some fruit juices such as orange, apricot, grape and apple has been investigated. During the clarification processes, the enzyme was more effective than crude extracts on the clarification of the peach juice with a ratio of 223.1% at most.     

Hygienic status and biogenic amine content of mung bean sprouts

 Microbiological analyses of commercial mung bean sprouts showed the total, viable microbiological population to exceed 10⁸ cfu/g. Enterobacter cloacae, Klebsiella pneumoniae and Enterobacter agglomerans were found to be the dominant and most frequently isolated microbial species. Putrescine, cadaverine, spermidine and spermine were detected in all samples investigated. Formation of biogenic amines by pure culture isolates was studied in a modified decarboxylase medium at different temperatures, pH values and atmospheres. Highest activities were found under aerobic conditions at 20  °C. K. pneumoniae 861 produced 1.2 mg cadaverine/ml after an incubation period of 24 h and E. cloacae 862 produced 2 mg putrescine/ml after 48 h of incubation. For E. agglomerans 863, no biogenic amines were detected under these conditions. Production of cadaverine by E. cloacae 862 and K. pneumoniae 861 under aerobic conditions is presumably related to lysine decarboxylase activities. Although highest decarboxylase activities have usually been found at acidic pH values, amine production reached a maximum at pH 7. Under anaerobic conditions, E. cloacae 862 produced only about half the amount of putrescine as under aerobic conditions, whilst K. pneumoniae 861 produced significantly less cadaverine but was able to produce putrescine. Received: 10 October 1997 / Revised version: 21 January 1998     

Hygienic status and biogenic amine content of mung bean sprouts

 Microbiological analyses of commercial mung bean sprouts showed the total, viable microbiological population to exceed 10⁸ cfu/g. Enterobacter cloacae, Klebsiella pneumoniae and Enterobacter agglomerans were found to be the dominant and most frequently isolated microbial species. Putrescine, cadaverine, spermidine and spermine were detected in all samples investigated. Formation of biogenic amines by pure culture isolates was studied in a modified decarboxylase medium at different temperatures, pH values and atmospheres. Highest activities were found under aerobic conditions at 20  °C. K. pneumoniae 861 produced 1.2 mg cadaverine/ml after an incubation period of 24 h and E. cloacae 862 produced 2 mg putrescine/ml after 48 h of incubation. For E. agglomerans 863, no biogenic amines were detected under these conditions. Production of cadaverine by E. cloacae 862 and K. pneumoniae 861 under aerobic conditions is presumably related to lysine decarboxylase activities. Although highest decarboxylase activities have usually been found at acidic pH values, amine production reached a maximum at pH 7. Under anaerobic conditions, E. cloacae 862 produced only about half the amount of putrescine as under aerobic conditions, whilst K. pneumoniae 861 produced significantly less cadaverine but was able to produce putrescine. Received: 10 October 1997 / Revised version: 21 January 1998     

Purification and characterization of Aspergillus oryzae LK-101 salt-tolerant acid protease isolated from soybean paste

A novel salt-tolerant acid protease was produced from Aspergillus oryzae LK-101 (AOLK-101). The AOLK-101 protease was purified to homogeneity by ammonium sulfate precipitation, DEAE-Sephadex A-50 and Sephadex G-100 chromatographies in order. The specific activity and the purification ratio of the purified protease were 2,301 unit/mg and 11.6 fold, respectively, with 25 kDa of molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrpphoresis (SDS-PAGE). Its optimal pH and temperature were pH 6.5 and 50°C, respectively. This protease was relatively stable at pH 4.5–7.5, below 40°C, and up to 10% salt concentration. The protease was moderately inhibited by Ag²⁺ and Zn²⁺, and strongly by ethylenediamide tetraacetic acid (EDTA) and phenylmethysulfonyl fluoride (PMSF), but activated by Cu²⁺ and Mn²⁺. Therefore, the AOLK-101 protease was a serine protease based on the influence of metal ions and inhibitors. K _m , V _max , k _cat , and k _cat /K _m values of AOLK-101 protease for hammastein milk casein were 1.04 mg/mL, 124.84 unit/L, 163.5/sec, and 3.9×10⁶/m·sec, respectively.     

Effect of Diamines, Polyamines and Tuna Fish Extracts on the Binding of Histamine to Mucin In Vitro

Binding of [ring-2-¹⁴C]-histamine to mucin was studied. Maximum binding of 2.5 μmol histamine/μmol mucin was observed at a histamine concentration of 0.5 mg/ml. Histamine binding was decreased by 46.5% by spermine, 25.3% by spermidine, 9.5% by cadaverine, and 11.1% by putrescine. These maximum effects were observed at molar ratios of histamine to polyamine of 1:1 for spermine and spermidine, 1:2 for cadaverine, and 1:2.3 for putrescine. The relative effects on histamine binding to mucin of extracts from wholesome canned tuna fish and a mixture of spermine, spermidine, cadaverine and putrescine were also examined. Although the total neutral aqueous extract of tuna had little effect on histamine-mucin binding (5.4% inhibition), the extract of bases from tuna and the prepared base mixture showed maximum inhibition of histamine binding to mucin of 23.1% and 21.4%, respectively. Certain other components of tuna extracts (NaCl, aspartic acid and glutamic acid) did not decrease histamine-mucin binding under the conditions used.     

Effects of gamma irradiation on the biogenic amines in pepperoni with different packaging conditions

Combined effects of gamma irradiation and packaging on biogenic amine (BA) formation in pepperoni sausage were investigated during storage. Pepperoni (fermented sausage) was made and packaged with air, vacuum and CO₂/N₂ (25%/75%) gas and then gamma-irradiated at 0, 5, 10 and 20 kGy. The pH was decreased after storage and non-irradiated samples showed a lower pH than irradiated. Lactic acid bacteria (LAB) were not detected after 5 kGy of gamma irradiation, while the LAB in the non-irradiated samples were 4–5 log counts during storage. A total of six different BAs, putrescine, cadaverine, β-phenylethylamine, spermidine, spermine and tyramine, were found in the pepperoni sausage. Detected BAs were statistically low under the irradiation or packaging conditions, except for cadaverine and β-phenylethylamine. Gamma irradiation was effective in reducing putrescine, spermidine, spermine and tyramine. Irradiation effects were not observed on the β-phenylethylamine level, while the CO₂/N₂ packaging caused increasing of the level. Most BAs detected were reduced by gamma irradiation of the pepperoni sausage during storage. However, CO₂/N₂ packaging was an improper condition for BA reduction in the pepperoni sausage.     

Purification and some properties of a cysteine proteinase from sorghum malt variety SK5912

A cysteine proteinase from sorghum malt variety SK5912 was purified by a combination of 4 M sucrose fractionation, ion‐exchange chromatography on Q‐ and S‐Sepharose (fast flow), gel filtration chromatography on Sephadex G‐100 and hydrophobic interaction chromatography on Phenyl Sepharose CL‐4B. The enzyme was purified 8.4‐fold to give a 13.4% yield relative to the total activity in the crude extract and a final specific activity of 2057.1 U mg^?1 protein. SDS—PAGE revealed two migrating protein bands corresponding to apparent relative molecular masses of 55 and 62 kDa, respectively. The enzyme was optimally active at pH 6.0 and 50 °C, not influenced across a relatively broad pH range of 5.0–8.0 and retained over 60% activity at 70 °C after 30‐min incubation. It was highly significantly (P < 0.001) inhibited by Hg²⁺, appreciably (P < 0.01) inhibited by Ag⁺, Ba²⁺ and Pb²⁺ but highly significantly (P < 0.001) activated by Co²⁺, Mn²⁺ and Sr²⁺. The proteinase was equally highly significantly (P < 0.001) inhibited by both iodoacetate and p‐chloromercuribenzoate and hydrolysed casein to give the following kinetic constants: K_m = 0.33 mg ml^?1; V_max = 0.08 µmol ml^?1 min^?1. Copyright © 2004 Society of Chemical Industry     

High apparent ileal digestibility of amino acids in raw and germinated faba bean (Vicia faba)‐ and chickpea (Cicer arietinum)‐based diets for rats

The effects of germinated faba bean (Vicia faba minor var Alameda)‐ and chickpea (Cicer arietinum kabuli var Athenas)‐based diets on performance, N utilisation, amino acid ileal digestibility and plasma concentrations were studied in growing male Wistar rats. Raw and germinated faba bean and chickpea seed meals were incorporated in essential amino acid‐supplemented and energy‐equalised diets as the only sources of protein. A lactalbumin‐based diet equalised in protein (100 g kg^?1) and digestible energy (15.5 kJ g^?1) with the test diets was used as control. Weight gains, gain/feed ratios, N retention and NPU values of animals fed raw or germinated legumes were lower than those of rats given the control (lactalbumin) diet, while faecal dry weights were higher. However, N retention and NPU values of rats fed germinated faba bean diets were higher and faecal dry weights lower than those of animals fed non‐germinated faba bean diets. Liver and thymus fresh and dry relative weights were lower than controls for all legume diets, whilst small intestine, caecum and colon relative weights were higher than controls for non‐germinated faba beans and chickpeas either germinated or not. Caecum and colon fresh and dry relative weights of rats fed germinated faba bean seeds were lower than those of rats fed non‐germinated faba beans and not different from controls. Except for aspartic acid and proline in rats fed raw faba bean diets, apparent ileal digestibilities of amino acids were not different or higher in rats fed legume diets as compared with controls. Except for arginine, apparent ileal amino acid digestibility was higher for germinated than for non‐germinated faba bean seeds. The amounts of glycine, arginine and ornithine in plasma significantly increased whilst those of threonine, alanine, leucine and lysine decreased with respect to controls in faba bean‐ or chickpea‐fed rats, either germinated or not. We conclude that (a) germination of faba bean seeds gave rise to a significant (P < 0.01) but limited improvement in performance, N retention and apparent ileal digestibilities of some amino acids in growing rats compared with non‐germinated seeds, while there was no detectable effect in the case of germinated chickpea seeds, and (b) the apparent ileal amino acid digestibility of essential amino acid‐supplemented diets based on faba bean or chickpea meals, either germinated or not, is similar or even higher than controls. © 2002 Society of Chemical Industry     

Polyphenol oxidase properties,anti-urease,and anti-acetylcholinesterase activity of Diospyros lotus L. (Plum Persimmon)

Diospyros lotus fruit polyphenol oxidase was purified using affinity chromatography, resulting in a 15-fold enrichment in specific activity. The purified enzyme, having 16.5 kDa molecular weight on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, exhibited the highest activity toward 4-methylcatechol. Maximum diphenolase activity was reached at pH 7.0 and 60°C in the presence of 4-methylcatechol. K_m and V_max values were calculated as 3.8 mM and 1250 U/mg protein, respectively. Ascorbic acid was a promising inhibitor with an IC₅₀ value of 0.121 µM. The activity of the purified enzyme was stimulated by Fe²⁺, Sr²⁺, Zn²⁺, and K⁺ and deeply inhibited by Hg²⁺, at 1 mM final concentration. Aqueous extract of Diospyros lotus L. fruit showed strong substantial urease and acetylcholinesterase inhibition, with IC₅₀ values of 1.55 ± 0.05 and 16.75 ± 0.11 mg/mL, respectively.     

Comparison of γ-aminobutyric acid accumulation capability in different mung bean (Vigna radiata L.) varieties under heat and relative humidity treatment,and its correlation with endogenous amino acids and polyamines

In this study, the accumulation of GABA and its inherent factors across different varieties of mung bean (Vigna radiata L.) in response to heat and relative humidity (HRH) were investigated. Results showed the average GABA content in mung bean varieties was increased 7.52 times following HRH treatment, and the black mung bean variety (A8) exhibited the highest GABA accumulation capability (1.76–84.57 mg per 100 g DW). From the perspective of GABA shunt metabolites, the free glutamic acid content of mung beans significantly decreased (P < 0.05) after HRH treatment and presented a significant correlation (P < 0.05) with GABA content. In polyamine degradation pathway, although the average levels of spermine and spermidine of mung bean varieties significantly decreased (P < 0.05) after HRH treatment, no significant correlation with GABA content was identified. Hence, the GABA accumulation was predominantly attributed to GABA shunt. Besides, free amino acids including glutamic acid, serine, ornithine, arginine and glycine in mung beans showed a significant positive correlation (P < 0.05) with GABA content and increment following HRH treatment, which suggested that mung beans enriched in these free amino acids might accumulate higher amounts of GABA after HRH treatment and be useful for industrial applications.     

Irradiation Effects on Biogenic Amines in Korean Fermented Soybean Paste During Fermentation

ABSTRACT: Irradiation effects on biogenic amines (BAs) and microbiological populations of Korean fermented soybean paste were investigated during fermentation. Soybean paste was prepared and irradiated with doses of 5,10, and 15 kGy, and then fermented at 25 °C for 12 wk. Bacillus spp. and lactic‐acid bacteria decreased by irradiation but increased during fermentation. Biogenic amines detected were putrescine, cadaverine, β‐phenylethylamine, spermidine, spermine, tryptamine, histamine, tyramine, and agmatine. A significant difference was not observed in BA content between control and irradiated samples immediately after gamma irradiation. However, 4 kinds of BAs, putrescine, tryptamine, spermidine, and histamine, showed significant reduction by irradiation during fermentation (P < 0.05).     

外源γ-氨基丁酸对鲜切南瓜品质和γ-氨基丁酸代谢的影响

以贝贝南瓜为原料,研究了外源GABA (γ-Aminobutyric acid, GABA)和其合成抑制剂3-巯基丙酸（3-Mercaptopropionic acid,3-MP）处理对鲜切南瓜品质和GABA积累的影响以及可能的作用机制。结果表明,外源GABA可以诱导内源GABA的积累,并促进南瓜中谷氨酸在谷氨酸脱羧酶（Glutamate decarboxylase,GAD）催化下转换成GABA。3-MP处理后的南瓜,GABA含量低于对照组,且GAD和GABA转氨酶（GABA transaminase,GABA-T）活性受到抑制。在多胺降解途径中,GABA处理组的多胺含量（腐胺、精胺、亚精胺）显著低于对照组,而3-MP处理抑制了多胺氧化酶（Polyamine oxidase,PAO）、二胺氧化酶（Diamine oxidase,DAO）和4-氨基丁醛脱氢酶（Aminoaldehyde decarboxylase,AMADH）的活性。说明GABA处理可以激活多胺降解途径,促进GABA在南瓜体内富集。同时在贮藏期间,外源GABA处理对南瓜最大菌落总数、色泽、β-胡萝卜素含量和可溶性固形物含量等均影响不大。     

Purification and Characterization of β-Glucosidase from Aspergillus niger

Aspergillus niger, an isolate of soil contaminated with effluents from cotton ginning mill was grown in Czapek-Dox medium containing sawdust, Triton-X 100 and urea for production of an extracellular β-glucosidase. β-Glucosidase enzyme was purified (86-fold) from culture filtrate of A. niger by employing ammonium sulphate precipitation and gel filtration on sephadex G-75. The molecular mass of the purified enzyme was estimated to be 95 kDa by sodium dodecyl sulphate polyacrylamide gel electrophoresis. The enzyme had an optimal activity on p-nitrophenyl β-D-glucopyranoside at 50°C and pH 5.0. The K_m and V_max of the enzyme on p-nitrophenyl β-D-glucopyranoside at 50°C and pH 5 were 8.0 mM and 166 µmol/min/mg of protein, respectively. The enzyme could hydrolyze cellobiose and lactose but not sucrose. Heavy metals like Hg²⁺, Al³⁺, and Ag⁺ inhibited the activity, whereas Zn²⁺ and detergents such as Triton-X 100 and Tween-80 increased the activity at 0.01%. The enzyme activity increased in the presence of methanol and ethanol.     

低氧联合NaCl胁迫下蚕豆发芽富集γ-氨基丁酸培养条件优化

以蚕豆(启豆2号)为原料,研究了低氧联合NaCl胁迫下培养条件对γ-氨基丁酸(GABA)富集的影响。结果显示:非胁迫培养时间、培养pH和胁迫培养时间显著影响发芽蚕豆GABA积累。蚕豆发芽富集GABA最佳培养条件是非胁迫培养1.5 d、培养液pH 3.5和低氧联合NaCl胁迫4 d,在此条件下其GABA含量可达1.06mg/g DW,为原料蚕豆的7.57倍。