Purification of Rhamnolipid biossurfactant by precipitation aiming applications in repellents against Aedes aegypti

• Grant number: 17/11907-8
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Effective date (Start): August 01, 2017
• Effective date (End): July 31, 2018
• Field of knowledge: Engineering - Chemical Engineering - Industrial Operations and Equipment for Chemical Engineering
• Principal Investigator: Igor Tadeu Lazzarotto Bresolin
• Grantee: Matheus Cabulon Ferreira
• Host Company: DC Química, Representação e Comércio de Produtos Químicos Ltda
• Associated research grant: 16/06090-0 - Ramnolipid: a natural repellent agaisnt Aedes aegypti, AP.PIPE

Abstract

Rhamnolipids are a type of biosurfactant that, according to several researches, have a promising potential against the mosquito Aedes aegypti and, because of that, there is a great need to study purification and recovery techniques, in order to find the best conditions for a large-scale production that be economically viable in the future. In general, precipitation is one of the most commonly used purification techniques because of its simplicity and low cost. Thus, this work aims the purification of rhamnolipid biosurfactant, by means the study of different precipitation techniques, such as acid (sulfuric and hydrochloric acids), with organic solvents (acetone and ethanol), by "salting-out" (ammonium sulfate) and by volatile salt (ammonium carbamate), the latter being unprecedented for this application. For the purified rhamnolipids, will be perform characterizations of physical-chemical properties (surface and interfacial tension, critical micelle concentration and emulsification index), structural characterizations (FTIR, NMR and ESI-MS), in addition to stability studies of pH, temperature and ionic strength. Thereby, it's aimed to determine which of the precipitation techniques is the most appropriate and viable to be applied, contributing, therefore, for the scientific literature and for the industry that operates in the research and development segment in this area, aiming future applications in repellents against Aedes aegypti. (AU)