| The yellow rice wine is one of the famous liquor in the world, which is also one of the three big ancient liquors of the world. The yellow rice wine is a wine with a mouth-filling, a harmonious and supple body, which is purely brewed from glutinous rice and wheat. It is not only rich in amino acids, peptides, oligosaccharides, vitamins and the human body needs of more than twenty different macro elements and micro elements, but also contains a variety of organic acids and polyphenols. However Escherichia coli is the main food -borne diseases, which may lead to illness in certain conditions. Therefore, the research of antibacterial activity of rice wine, which can be providing scientific basis for disease-resistant.The bactericidal activity of yellow rice wine and the main components of the yellow rice wine (ethanol and organic acids) against the important food-borne pathogen Escherichia coli were tested. The antibacterial effect was evaluated by its bacteriostatic ratio.The main results were as follows:First of all, this experiment measured ethanol content in yellow wine of was Guyue Longshan 15%(v/v) by a hydrometer.This study optimized the method of HPLC, which was used for determining the main organic acids of yellow rice wine. Under these conditions: ZORBAX Eclipse XDB-C18(4.6×150mm,5.0μm),mobile phase was potassium dihydrogen phosphate of 0.05 mol·L-1 (pH2.90), the velocity of flow was 0.8 mL per min, the column temperature was 30℃, the determine wavelength was set at 210nm, then the wine samples were analyzed by injecting into HPLC directly after clarification by centrifuge. The content of organic acids were as follows: oxalic acid 1527.6mg/L, tartaric acid 934.8 mg/L, malic acid 610.1 mg/L, lactic acid 5699.1 mg/L, acetic acid 6155.9 mg/L, citric acid 235.6 mg/L and succinic acid 1951.5 mg/L. In the whole experimental time, only a 2 log cycles reduction was obtained in the 30 mL of yellow rice wine. The addition of 60 or 130 mL showed a higher inhibitory effect, which specially noted in the first 30 min. These quantities of wine led to a reduction of 3 and almost 5 log cycles, respectively.The 15%(v/v) ethanol had a little effect on the survival of Escherichia coli in the first 20 min, a higher effect being noted from that time on. The bacterial survival rate was from 100% to 5.2%, just a 1 log cycles reduction was discovered.Organic acids of yellow rice wine showed a higher bactericidal effect than ethanol. When tested the organic acids separately, tartaric acid (0.94g/L), citric acid (0.24g/L) and succinic acid (1.95g/L) caused a 2 log cycle survival reduction; lactic (5.67g/L), malic acid (0.61g/L), acetic acid (6.16g/L) and oxalic acid (1.53g/L) were found to have stronger effect, and the survival rate of Escherichia coli was all down to 0.1% at the end of experiment time.Organic acids with ethanol had shown the different antibacterial ability on Escherichia coli. Within the former 20 min at the experiment time, lactic, acetic acid, oxalic acid and malic acid were found to lead the survival of Escherichia coli from 100% to 0.8%, 1.6%, 8.1%, 1.2%, respectively. In the above four organic acids with ethanol separately, the survival rate of Escherichia coli were 0.5%, 0.4%, 0.3%, 0.2%, respectively. It demonstrated that the mixture of organic acids with ethanol had a more effective inactivation on the E.coli, and they played the synergism antibacterial role.This work clearly demonstrated that yellow rice wine exerts a strong bactericidal effect on Escherichia coli. The results obtained in simulated consumption scenarios, suggested that concurrent ingestion of wine with food significantly decreases the number of Escherichia coli persisting further in the alimentary tract.
|
PDF Full Text Request