Comparative study on potentials of Camellia oleifera shell saponins as foam cleaning agents in the late growth stage

Camellia oleifera Able fruit shell (COS) is a valuable lignocellulosic waste resource. The objective of this study was to evaluate the variability in properties of COS saponins during the late growth stage and their potential as agents for foam cleaning. We tested the physical parameters of camellia fruits collected from five maturity stages, analyzed the chemical components of COS, as well as extracted saponins to evaluate their structure, surface tension, foaming property, wettability, and cleaning power. The findings revealed a gradual decrease followed by an increase in saponin content as maturity progressed. Notably, COS saponin exhibited the lowest surface tension (33.10 mN/m) and superior wettability (32.87°) 4 weeks before ripening. The foaming capacity of COS saponins reaches up to 163% with a stability exceeding 95%. Moreover, the detergency of COS saponins is comparable to that of commercial detergents. This study contributes to the adequate utilization of camellia shell saponin, and gives implications for its applications as environmentally foam cleaning agents.