Analysis of natural wax from Nelumbo nucifera leaves by using polar and non-polar organic solvents

Abstract

Nelumbo nucifera (lotus) is a unique aquatic plant. Its leaves are covered with superhydrophobic wax layer which protects it from the environmental wearing. In this study, the extraction yield and the functional group profile of crude lotus leaf natural wax have been observed. The lotus leaf wax has been extracted by using many polar and non-polar solvents through different extraction methods. The superhydrophobic wax was successfully extracted from the non-polar solvents i.e. benzene, toluene, xylene, petroleum ether; whereas the polar solvents used (ethanol and ethyl acetate) did not extract the superhydrohobic wax. The results show the highest extraction yield was observed with xylene and the extract in toluene exhibited the best lotus leaf surface-like behavior. Conventional extraction method of maceration provides a slightly higher extraction yield compared to the Soxhlet extraction. For the extract in xylene, maceration provided an extraction yield of 4.37 % and Soxhlet extraction provided a yield of 3.54 %. The TLC performed on the extracts depicted the presence of both polar and non-polar compounds. The FTIR analysis confirmed the presence of alkane chains in the crude natural wax extract. If utilized properly, the lotus leaf natural wax can help mankind in providing cost-effective and affordable waterproofing solutions.