Improving Solubility, Stability and Permeability of Natural Products Extracts

Project Summary Abstract Despite substantial developments of extraction and separation techniquesisolation of natural products from various sources is still a challenging taskand lead generation or validation of known natural products from plant extracts is fraught with false negativese gdue to low concentrationsinstabilityor insolubilityand false positivese gaggregatesand knownpatented or nuisance compoundsTraditional and optimized solvent based extraction methodsincluding those involving ultrasoundmicrowavesand pressure assisted extractionsupercritical fluids and solid phase extractionionic liquids and distillation have all been reported as a means to extract and separate components of different physicochemical propertiesand de replication of already known or nuisance compounds at the earliest stage of the fractionation procedure is desirableWe propose to utilize natural polymericdifferent molecular weight chitosan and methylated derivativesnanoformulationstypically employed in the lead optimization or drug development process to improve therapeutic efficacy and or reduce toxicityin the lead discovery process by employing them in the extraction process to solubilize and stabilize natural products for biological testingA proof of concept will be demonstrated with green tea extracts through the isolationquantification and assay of biological activity of the major known catechinsin particular EGCGthat react rapidly with reactive oxygen speciesROSas compared with their non nanoformulated counterpartsIn additionstudies have demonstrated a modest cholesterol lowering effect with green tea catechin extractsincluding EGCGAlthough statins have been on the market as inexpensive and safe means to control cholesterol levelsnevertheless there remains a substantial market of unmet medical need for people who are statin intolerant or statin resistantThe long term goal of this work is to demonstrate the general utility of applying nanoformulations to natural products drug discoveryin particular extraction and isolationand to developin a Phase II grantan optimized EGCG nanoformulation and test for enhanced efficacy in an animal model of cholesterol lowering in a preclinical development phaseThe specific aims of this work are toPerform nanoformulationstability and release kinetic studies with several novel natural polymer basednanoformulation methods in the green tea extraction process to improve the extraction efficiency of themajor catechinsespecially EGCGand perform stability and simulated release kinetic studies with the bestnanoformulations as compared to their non nanoformulated counterpartsRun cell based assays for measuring cholesterol absorption inhibition with the best three nanoformulatedextracts from specific aimagain comparing the biological activity to their corresponding nonnanoformulated counterpartsConfirm LDL and total cholesterol lowering in a mouse model with the best nanoformulation from specificaimwith purified EGCG in mice maintained on high fat diets to measure LDL and total cholesterollowering to demonstrate improved efficacy as compared to its non nanoformulated counterpart Project Narrative Isolation of natural products from various sources is still a challenging taskand lead generation and validation of novel or known natural products is fraught with false negatives and false positivesOur goal is to improve the efficiency of natural drug discovery during the important extraction and isolation process through application of nanoformulations to better solubilize and stabilize the chemical constituents for testing