Fermentation of Cucumber Extract with Hydromagnesite as a Neutralizing Agent to Produce an Ingredient for Dermal Magnesium Products

Magnesium is an essential element involved in various biochemical processes in the human body. In addition to oral supplementation, topical magnesium application is another conventional form of magnesium delivery for the treatment of skin diseases and muscle inflammation. Cucumber extract is a well-known superfood for human skin. It has been widely used in various skincare product lines because of its known benefits to the skin. The benefit of cucumber extract to the human skin would be significantly enhanced if the cucumber extract was fermented to convert the reducing sugars to beneficial organic acids. In this study, we developed a protocol for lactic acid fermentation of cucumber extract using hydromagnesite as a neutralizing agent. Various lactic acid bacteria were screened for fermentation of cucumber extract. The best fermenting performance was observed with Lactobacillus paracasei, which could convert approximately 13 g/L of reducing sugars (glucose and fructose) to lactic acid and a minor amount of acetic acid within 2 days of incubation. The final fermented cucumber extract contains magnesium in the form of salts of organic acids, which have high absorption ability and bioavailability. The product is a potent ingredient for producing dermal magnesium products.