Antioxidant Japanese plum (Prunus salicina) microparticles with potential for food preservation

Abstract

Fiber microparticles (MPCs) obtained from Japanese plum (Prunus salicina) skin and flesh through ethanolic extraction retained polyphenolic compounds, mainly proanthocyanidins, in 200-170 mg/100gMPCs levels. Also, phenolics such as anthocyanins (cyanidin 3-galactoside and 3-rutinoside), responsible for red-purple colour, and flavonoids (quercetin derivatives), were found in significant proportions only in the skin MPCs. The MPCs-polyphenolic extract showed antioxidant capability (DPPH and FRAP assays) as well as protective effect against the oxidative stress induced by tert-butylhydroperoxide (t-BOOH) when biologically evaluated on kidney cells, joined to a low citotoxicity (50% cytotoxic concentration > 100 μg/mL). This is important since health benefits of barely absorbed proanthocyanidins rest on their permanence into the intestine, interfering with oxidative stress implicated in inflammatory disorders. Higher proportions of pectins found in flesh MPCs and of lignin in skin MPCs can provide different fibre functionality. Plum MPCs obtained can be useful as antioxidant natural additives and ingredients for functional food preservation.