Investigating the Effect of Shahani Grape Juice and Shahani Grape Drink Containing Lactobacillus Plantarum Paraprobiotic on Reducing Stress in Management Field Students

Abstract

Background and purpose: Stress is a behavioral process that helps humans to increase survival. Stress refers to any biological response to an internal or external stimulator. Stress is difficult to study because of its widespread effect on different parts of the body. A good diet is essential for maintaining mental and physical health. During stress time, eating habits are greatly disrupted and this can cause nutritional deficiencies that may lead to more stress on the body. In stressful situations, the body uses more nutrients than usual. So a good diet is required, as a poor diet causes deficiencies that lead to more stress and health problems. Since 2004, many scientific studies have proven the functional and health-promoting properties of non-living probiotics. In recent years, research has been conducted on the consumption of deactivated cells of probiotics (paraprobiotics) whose positive effects have been proven in some studies. In the current research, lactobacillus plantarum paraprobiotic cells have been used in Shahani grape drinks to reduce stress in master's degree students. Materials and methods: The production of paraprobiotics is done in different ways, including heating, applying ultrasound, ultraviolet radiation, infrared radiation, ionizing rays, applying high hydrostatic pressure, and using some chemical compounds. Each of these inactivation methods cause changes in the structure and functional characteristics of non-living probiotic cells. High-power ultrasound was used for deactivation. the suspension containing parapsychobiotic was evaluated for the amount of the active ingredient gamma-aminobutyric acid using a high- performance liquid chromatography. Inactivated cells were added to the reconstituted Shahani grape juice. 32 healthy students consumed a control drink and a drink containing paraprobiotics daily for 10 weeks during the end-of-semester exams. Results: The use of paraprobiotics obtained from inactivation methods is useful when the health-giving compounds and metabolites are not completely reduced or destroyed under the influence of the inactivation method. Gamma-aminobutyric acid (GABA) is the most important inhibitory neurotransmitter in the central nervous system and plays an important role in coordinating brain function and reducing anxiety and stress. The results showed that the amount of gamma-aminobutyric acid in the suspension of parapsychobiotics was higher than in the suspension of live bacteria. Subjects who consumed a grape juice drink containing parapsychobiotics had higher general health scores than the control group during exams. The use of paraprobiotics in drinks improved the quality of sleep. At the end of the test, the amount of cortisol in the saliva of the control group was higher than the parapsychobiotic treated group. Conclusion: The results of this research showed that Lactobacillus plantarum paraprobiotic has potential benefits for improving mental health. Based on the results of this research, paraprobiotics, by affecting the human brain axis, reduce the secretion of stress hormones such as cortisol and, as a result, increase mental stability during the final semester exams of students. (Clinical Trials Registry Number: IRCT20240128060833N1)

Keywords

• paraprobiotic
• grape juice
• cortisol
• central nervous system
• lactobacillus plantarum