Screening of Lactic Acid Bacteria Capable to Breakdown Citric Acid during Ivorian Cocoa Fermentation and Response of Bacterial Strains to Fermentative Conditions
Journal Title: Biotechnology Journal International - Year 2016, Vol 10, Issue 3
Abstract
Aims: The breakdown of citric acid contained in the pulp during cocoa fermentation is an important and key property for bacterial growth and for obtaining a well fermented cocoa. The objective of this study was to analyze citrate metabolism in lactic acid bacteria (LAB) isolated from Ivorian fermenting cocoa beans and evaluate their capacity to grow effectively under fermentation conditions. Place and Duration of Study: Laboratory of Biotechnology, UFR Biosciences, University Félix Houphouet-Boigny (Côte d’Ivoire), between August 2014 and April 2015. Methodology: Spontaneous heap fermentations were conducted in three cocoa producing regions during 6 days. Bacteria isolation was performed using plate culture on MRS medium and strains were screened for citrate metabolism using Kempler and McKay medium whereas gas and acetoin productions from citrate were searched. Additionally, the viability of cells under stress conditions related to cocoa fermentation was tested. Results: The results show that a wide rate of LAB strains (75%), mainly heterofermentative possess citrate metabolism, and most of these strains produce gas from citrate but were not able to produce acetoin from citrate. Moreover, some LAB presenting citrate metabolism show a remarkable thermotolerance at 45°C with more than 50% of survival growth rate (SGR), while some exhibited a poor viability (less than 10%) at this temperature. Ethanol at 8-12% was found to have no adverse effect on bacterial growth. In contrast, lactic acid, acetic acid and citric acid exerted individually full inhibition on LAB strains that failed to grow at 0.4% of acid. Conclusion: Taken together, the results indicate that strains studied may preferentially produce lactic acid from citrate and their high proportion should contribute to efficiently break down citric acid during cocoa fermentation. However, occurrence of a high acidity could seriously limit the growth of these valuable potential starter strains in fermentation conditions.
Authors and Affiliations
Honoré G. Ouattara, Djeneba H. Ouattara, Jacques N. Adom, Bernadette G. Goualié, Gisèle A. Koua, Ginette G. Doué, Sebastien L. Niamke
Keywords
Related Articles
- EP ID EP237687
- DOI 10.9734/BBJ/2016/19279
- Views 112
- Downloads 0
Optimizing Salting and Immersion Time in Liquid Smoke of Farmed Gilthead Sea Bream (Sparus aurata) Fillets Using Response Surface Methodology
Aims: To produce smoked gilthead sea bream fillets using the liquid smoke dipping method during brining and optimize the brining-smoking process using the response surface method. Study Design: The experimental design wa...
Establishment of Agrobacterium-Mediated Transformation System in Sweet Potato (Ipomoea batatas) by Culture of Leaf Segments for Functional Analysis of ASG-1, an Apomixis-Specific Gene
Aims: In order to do the functional analysis of apomixis-specific gene (ASG-1), which was isolated from apomictic guineagrass, the sweet potato was used to establish an Agrobacterium-mediated transformation system. Study...
Phytochemical Screening and Effect of Temperature on Proximate Analysis and Mineral Composition of Zingiber officinale Rosc.
Aims: To investigate the phytochemical composition and effect of temperature on the proximate and mineral composition of Zingiber officinale. Study Design: Activity directed phytochemical screening, proximate analysis a...
Plasmid and Restriction Endonuclease Analyses of Bacteria Associated with Pneumonia in HIV/AIDS Patients in Ekiti State, Nigeria
Bacterial infections are an important cause of morbidity and mortality in individuals with the human immunodeficiency virus. The emergence of multiple-drug resistant bacteria has been documented by many researches. This...
Biovalorization of Olive Mill Waste Water for the Production of Gellan Gum from Sphingomonas paucimobilis
Aims: The aim of this work was to investigate and optimize the potential of olive mill waste water (OMWW) to be utilized as a substrate for the production of gellan gum by Sphingomonas paucimobilis. Study Design: The st...