Preparation and efficacy assessment of malva nut polysaccharide for skin hydrating products.

INTRODUCTION: Scaphium scaphigerum or malva nut has long been served in Chinese medicine. However, the use of this herb in modern health care applications has, to date, been rarely reported.

MATERIALS AND METHODS: Maceration of the herb in water afforded malva nut polysaccharide which was standardized. Safety and skin hydrating efficacy of the polysaccharide and products were evaluated in human volunteers.

RESULTS: Malva nut polysaccharide (41.71±0.64%) having 36.58±0.51% total sugar content was isolated, with further analysis quantifying ash, carbohydrate, reducing sugar and moisture contents to be 6.05±0.00, 40.06±1.00, 12.20±0.05 and 12.64±0.31%, respectively. The polysaccharide exhibited swelling and hydrating capacities of 0.46±0.01% and 54.46±0.02g/g, with L*, a* and b* of 52.56±0.04, 9.02±0.06 and 18.42±0.03, respectively, and a viscosity of 1263.00±2.00 cps. Accelerated testing indicated the biopolysaccharide to be stable, resulting in no skin irritation in 15 human volunteers. The skin hydrating efficacy as assessed via a randomized single-blind, placebo-controlled study in 24 volunteers highlighted the superior performance of malva nut over the vehicle (moisture retainment for 70min as examined by Corneometer® CM 825). A stable skin moisturizing gel containing malva nut was developed and was shown to exhibit improved performance over benchmark tamarind and algae polysaccharide gels (after 180min observation).

CONCLUSION: Malva nut polysaccharide has potential as a key ingredient in skin hydrating products, which should encourage its further development.