OPTIMIZATION OF KOMBUCHA CULTURE FERMENTATION IN WATER EXTRACT OF ROBUSTA GREEN COFFEE BEANS (COFFEA CANEPHORA L.) AS A WEIGHT LOSS AGENT

• Main Author: Narko, Tedjo
• Format: Dissertations
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/51283
• Institution: Institut Teknologi Bandung

World Heatlh Organization (WHO) defines overweight and obesity as abnormal or excessive fat accumulation that may impair health. The fundamental cause of obesity and overweight is an energy imbalance between calories consumed and calories expended. Eating a healthy diet and getting more physical activities can help prevent obesity. Certain food and beverages have been varied to be used for reducing body weight. Caffeine is one of compounds known be able to reduce body weight or help prevent weight gain. However, there is only small number scientific evidences which show that caffeine consumption leads to weight loss. Caffeine is found in many beverages including coffee, which. is usually prepared in a form of brewed drink from roasted coffee beans and kombucha coffee (KC). KC has gained popularity over the past couple of years. KC is a fermented coffee bean extract with the addition of kombucha culture. It has been applied to many types of coffee beans such as the black and green. Green coffee beans contain several components, mainly caffeine and chlorogenic acids. They are important for flavor formation and their extracts influence human’s health. In losing body weight, caffeine in green coffee beans extract breaks down fat into free fatty acids, while the chlorogenic acid accelerates fat metabolism in the liver. Several efforts have been made to enhance the concentration of chlorogenic acid in green coffee beans extract, for example using fermentation of green coffee beans in water extract with the addition of kombucha culture. This study aims to optimize conditions the fermentation of robusta green coffee bean extract with addition of kombucha culture and to perform further studies related to its potential activity and safety such as: acute toxicity test, interaction study of caffeine and chlorogenic acid with pancreatic lipase enzyme, prediction of toxicity, in vitro and in vivo tests on weight loss using zebrafish (Danio rerio), and hedonic test on fermented KC products. This research was started by testing four types of robusta green coffee beans from Garut, Soreang, Aceh and Ciwidey. The tests were conducted to determine the pH of the KC fermentation, and the concentration of caffeine and chlorogenic acid by High Performance Liquid Chromatography (HPLC). The fermentation process was carried out for 18 days and sampling was taken on day 0, 6, 12 and 18. The fermentation was optimized using Response Surface Methodology (RSM) method with Minitab Ver 17, with 3 research parameters, namely sugar concentration, incubation temperature, and incubation time. KC product was then analyzed for acute toxicity test using zebrafish (Danio rerio), and the toxicity prediction test using the Kroes TTC decision tree parameter. Further, interaction study of caffeine and chlorgenic acid with pancreatic lipase enzyme 3PE6 was carried out by using in silico methods. Pharmacological activity as anti-obesity of KC was tested on pancreatic lipase inhibition and in vivo testing using the zebrafish (Danio rerio). The hedonic and descriptive tests for KC products were also done in the research involving male and female respondents. The results showed that the pH of KC after 18 days fermentation were reduced to 2.6±0.1, 2.5±0.2, 2.7±0.2, 2.6±0.1 for green coffee from Garut, Soreang, Aceh and Ciwidey, respectively. Meanwhile the respective caffeine concentrations were reduced to 24.14±1.87, 22.23±1.15, 22.21±1.36, and 24.02±1.14 mg/L. And the the respective chlorogenic acid levels were increased to 151.53±0.50; 148.32±1.21; 136.24±1.38; 143.76±1.08 mg/L. Result of experimental analysis using HPLC compared with RSM testing showed no significant difference. The percentage of deviation for caffeine concentration was in the range of 0.17-3.19% and 0.32-2.99% for chlorogenic acid. The optimum condition of fermentation was achieved at sugar concentration of 6.77% w/v, incubation temperature of 25 °C and incubation time of 18 days. Acute toxicity test was based on the occurrence of defects in zebrafish embryos after KC administration. LC50 was obtained at a value of 1294.29 ppm. This LC50 was catagorized as safe according to the Organisation for Economic Cooperation and Development (OECD). Based on the Kroes TTC decision tree parameters, caffeine compounds and chlorogenic acid in KC were at safe exposure threshold values. Interaction study of natural ligands, caffeine, and chlorogenic acid revealed energy binding values of -13.33; -5.61; -8.01 kcal/mol, respectively. This interaction indicated that natural ligands, caffeine, and chlorogenic acid shared the same amino acid residue, i.e ALA51, while caffeine and natural ligands shared the same amino acid residues, i.e ALA51 and MET123. In vitro anti obesity test using pancreatic lipase enzymes showed that KC had an IC50 value of 5.39 ppm. Pharmacological activity tests using zebrafish (Danio rerio) after KC administration at 250, 500, 1000 ppm resulted in decreases in Body Mass Index (BMI) by 3.13, 6.67, and 9.09%, respectively. The treatments also decreased the respective body weight by 8.84, 13.62 and 19.48%; glucose levels by 19.27, 20.72, and 22.12%; and triglyceride levels by 28.47, 30.47, and 37.76%. Hedonic and descriptive tests were carried out by distributing questionnaires and KC product taste testing. The results showed that the respondents preferred the original KC to flavored KC. In conclusion, results of the present study suggest that KC can potentially be used for weight loss program.