Effect of GABA Extract of Black Sticky Rice with Giant Embryo on Alcohol-Related Indices After Acute Alcohol Intake in Social Drinkers

Screening of lactic acid bacteria strains isolated from Iranian traditional dairy products for GABA production and optimization by response surface methodology

A total of 50 lactic acid bacteria (LAB) isolates from Iranian traditional dairy products (Motal and Lighvan cheeses, and artisanal yogurt) were screened for gamma-aminobutyric acid (GABA) production. Firstly, a rapid colorimetric test was performed to evaluate the glutamate decarboxylase (GAD) activity among the LAB isolates examined. Thin layer chromatography (TLC) was then performed on selected strains to identify isolates with high/moderate GABA producing capacity, and a GABase micro-titer plate assay was employed to quantify GABA. Finally, two Lactococcus (Lac.) lactis strains were selected for GABA production optimization via Response Surface Methodology (RSM) following Central Composite Design (CCD). Forty-one out of the 50 isolates showed GAD activity according to the colorimetric assay. Eight isolates displayed strong GAD activity, while nine showed no activity; low to moderate GAD activity was scored for all other isolates. GABA production was confirmed by TLC in all isolates with high GAD activity and in four selected among isoaltes with moderate activity. Among the Lactococcus strains tested, Lac. lactis 311 and Lac. lactis 491 were the strongest GABA producers with amounts of 3.3 and 1.26 mM, respectively. These two strains were subjected to GABA production optimization applying RSM and CCD on three key variables: Monosodium glutamate concentration (MSG) (between 25 and 150 mM), incubation temperature (between 25 and 37 °C), and pH (between 4.0 and 5.0). Optimal conditions for GABA production by Lac. lactis 311 and Lac. lactis 491 of temperature, pH and MSG concentration were, respectively, 35.4 and 30 °C, pH 4.5 and 4.6, and MSG concentration of 89 and 147.4 mM, respectively. Under the above conditions, the amount of GABA produced by Lac. lactis 311 and Lac. lactis 491 was 0.395 and 0.179 mg/mL, respectively. These strains and the optimal culture conditions determined in this study could be used for the biotechnological production of GABA or applied in food fermentations for the development of naturally GABA-enriched foods.

Effect of Extract of Black Sticky Rice with Giant Embryo on Alcohol Cravings of Korean Social Drinkers: A 12-Week Randomized, Placebo-Controlled Trial

We investigated the effect of black sticky rice with giant embryo (BSRGE) extract known to contain high levels of gamma-aminobutyric acid (GABA) on alcohol cravings in social drinkers. A total of 41 subjects were divided into a BSRGE extract group (G group: n = 21) and a placebo group (P group: n = 20), and a randomized placebo-controlled experiment was performed for 12 weeks. The G group took the BSRGE extracts that contained 30 mg of GABA per day. (1) In the Pennsylvania Alcohol Craving Scale, there was a tendency for time and group interaction between the two groups (P = .087) on the total score. (2) In the Obsessive-Compulsive Drinking Scale (OCDS), there was a significance for time and group interaction between the G and P groups (P = .011) on the obsessive subscale. The total score of the OCDS showed significant time and group interactions between the G and P groups (P = .011). Our results showed that the extract of BSRGE containing a high level of GABA significantly reduced alcohol cravings in Korean social drinkers.

The association between alcohol metabolism and genetic variants of ADH1A, SRPRB, and PGM1 in Korea

BACKGROUND

Excessive alcohol consumption is a major public health problem in East Asian countries. Alcohol use leads to a cascade of problems including increased chances of risky behavior and a wide range of negative health consequences, from alcoholic liver disease to upper gastric and liver cancer. These alcohol effects are known to be influenced by ethnic variability and genetics.

METHODS

In this study, subjects were administered a single dose of alcohol (0.6 g/kg for men or 0.4 g/kg for women), and blood alcohol and acetaldehyde concentrations were measured eight times over 5 hours. To investigate genetically susceptible factors to alcohol metabolism, we selected single-nucleotide polymorphisms (SNP) of genes identified by prior genetic association studies for alcohol metabolism, alcohol consumption, alcohol dependence, and related traits, and performed genotyping on all subjects (n = 104).

RESULTS

We identified variations in the ADH1A, SRPRB, and PGM1 genes, which are directly associated with blood alcohol or acetaldehyde concentrations. Namely, the T allele of SRPRB rs17376019 and the C allele of PGM1 rs4643 were associated with lower blood alcohol levels, while the ADH1 rs1229976 C allele group exhibited markedly higher blood acetaldehyde levels than those of the ADH1 rs1229976 T allele group.

CONCLUSION

This study demonstrates that genetic variations in ADH1A, SRPRB, and PGM1 are associated with variations in blood alcohol and acetaldehyde concentration after alcohol intake.

The Effect of Oral Administration of Black Sticky Rice with Giant Embryo on Brain GABA Concentrations

OBJECTIVE

Black sticky rice with giant embryo (BSRGE) contains high GABA content and affects alcohol-related indices among social drinkers, and alcohol intake and anxiety-related behavior of mice. However, it is unknown whether the intake of BSRGE affects GABAergic activity of brain directly. The purpose of this study is to elucidate the effect of oral administration of BSRGE on brain GABA concentrations compared with commercially available GABA compound and regular feeds.

METHODS

Twenty-one male C57BL/6 mice were assigned to BSRGE, a regular feed (AIN-76) lacking GABA, and a regular feed containing GABA compound. After feeding freely for 48 h, the cortex and striatum were separated from the brain. An enzyme-linked immunosorbent assay was conducted to measure GABA and glutamate concentrations in mouse brain.

RESULTS

The GABA concentration of the BSRGE group was higher than that of regular feed and GABA compound group (p<0.001). However, the GABA compound group showed no significant difference from the regular feed group (p=0.50).

CONCLUSION

Intake of BSRGE containing high GABA content increased GABA concentrations in mouse brain compared with regular feed unlike GABA compound. The results of this study constitute an important basis for further investigations into the clinical applications of BSRGE.

Recent advances on bioactivities of black rice

PURPOSE OF REVIEW

Black rice has been consumed for centuries in Asian countries such as China, Korea or Japan. Nowadays, extracts and derivatives are considered as beneficial functional foods because of their high content in several bioactive molecules such as anthocyanins, other phenolics and terpenoids. The purpose of this review is to summarize and discuss recent developments on black rice bioactivities.

RECENT FINDINGS

Some sterols and triterpenoids with potential anticancer properties already tested in vitro and in vivo have been isolated and identified from bran extracts of black rice. Protection against osteoporosis has been suggested for the first time for black rice extracts. Because of its antioxidant and anti-inflammatory properties, black rice also protects liver and kidney from injuries. One clinical study reported the interest of black rice in case of alcohol withdrawal.

SUMMARY

Several advances have been recently achieved on the understanding of the potential biological effects of black rice and its derivatives. They further confirm that black rice should be considered as a promising source of health-promoting functional foods targeting a large set of noninfectious diseases. However, more clinical studies are needed to support the findings highlighted in this review.

Effect of Feeding High Gamma-Aminobutyric Acid-Containing Giant Embryo Black Sticky Rice (Oryza sativa L.) on Anxiety-Related Behavior of C57BL/6 Mice

The aim of this study was to determine the effect of feeding high gamma-aminobutyric acid (GABA)-containing black sticky rice giant embryo (BSRGE, Oryza sativa L.) on anxiety-related behavior of C57BL/6 mice. Experimental feedstuff (BSRGE with high GABA+AIN-76A) and control (AIN-76A) were provided to C57BL/6 mouse for 10 days. Antianxiety effects of BSRGE with high GABA were measured using an elevated plus maze. On day 8, the number of open arm entries by GABA and control groups were 1.10 ± 1.60 (mean ± SD) and 0.00 ± 0.00 (P = .030). On day 10, the number of open arm entries by the GABA group was 2.00 ± 1.89, which was significantly (P = .025) higher than that in the control group (0.40 ± 0.84). On day 8, the time the mice spent in open arm in the GABA group and control group was 3.60 ± 7.06 and 0.00 ± 0.00 sec (P = .068), respectively. On day 10, the time the mice in the GABA and control groups spent in open arm was 6.20 ± 5.35 sec and 1.80 ± 3.82 sec (P = .042), respectively. In repeated analysis of variance for the number of entries into open arm and time spent in open arm, significant differences were found between the two groups. Therefore, BSRGE with high GABA content might have an antianxiety effect. This study can serve as a preliminary study so that further antianxiety effects of BSRGE can be determined in more extended animal or clinical research studies in the future.