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Polyphenols from Nerone Gold 26/6, a new pigmented rice, via non‐conventional extractions: antioxidant properties and biological validation
Author(s) -
Ferrari Pier Francesco,
Pettinato Margherita,
Casazza Alessandro Alberto,
De Negri Atanasio Giulia,
Palombo Domenico,
Perego Patrizia
Publication year - 2021
Publication title -
journal of chemical technology and biotechnology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.64
H-Index - 117
eISSN - 1097-4660
pISSN - 0268-2575
DOI - 10.1002/jctb.6694
Subject(s) - gallic acid , polyphenol , extraction (chemistry) , chemistry , antioxidant , chromatography , anthocyanin , nutraceutical , yield (engineering) , solvent , flavonoid , food science , high performance liquid chromatography , biochemistry , materials science , metallurgy
BACKGROUND Pigmented rice is rich in coloured molecules known as anthocyanins, which exhibit a strong antioxidant activity and are used as additives to improve both the aspect and nutraceutical value of food. RESULTS In this work, Nerone Gold 26/6 was employed as raw material for the extraction of antioxidants varying solvents and the operating conditions by evaluating three different techniques, i.e., (1) conventional solid–liquid extraction, (2) high pressure and temperature extraction, and (3) ultrasound‐assisted extraction. The quality of extracts was assayed by determining their total polyphenol yield, total flavonoid yield, total anthocyanin yield, and the antioxidant activity by spectrophotometric analyses, as well as the phenolic profile by high performance liquid chromatography. High pressure and temperature extraction presented the highest content of polyphenols (14.0 ± 1.10 mg gallic acid equivalents /g dried biomass ) using a green solvent as ethanol 70% (v/v), while ultrasound‐assisted extraction carried out for 20 min showed the highest anthocyanin content (7.5 ± 0.94 mg malvidin equivalents /g dried biomass ). Both of the extracts were biologically validated on human endothelial cells. CONCLUSION Among the non‐conventional techniques, high pressure and temperature extraction at 60 °C and ultrasound‐assisted extraction for 20 min provided high total polyphenol, flavonoid, and anthocyanin yields and antioxidant activities compared to solid–liquid extraction. Both extracts were well tolerated by endothelial cells in a concentration ranging from 0.0125 to 0.0500 mg gallic acid equivalents /mL extract . Finally, solid phase extraction was responsible of a further increase of the extract biocompatibility. © 2021 Society of Chemical Industry (SCI).