Enzyme-assisted biotransformation increases hesperetin content in citrus juice by-products

• Published in: Food research international 2019-10, Vol.124, p.213-221
• Main Authors: Ruviaro, Amanda Roggia, Barbosa, Paula de Paula Menezes, Macedo, Gabriela Alves
• Format: Article
• Language: English
• Subjects: Aglycones; Bioconversion; Citrus waste; Enzymatic reaction; Hesperetin; Phenolic compounds; Tannase
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2018.05.004

Juice extraction from citrus fruits generates large amounts of residues, which account for 50% of the fruit weight. Citrus juice by-products (CJBs) are a rich source of phenolic glycosides. The enzyme-assisted extraction and biotransformation of phenolic compounds from CJBs were investigated. Pectinase, cellulase, tannase and β-glucosidase were used individually or in combination. The effects of enzymes to improve the release and bioconversion of phenolics from citrus residues were evaluated. Enzymes facilitated the extraction of phenolics from CJB and promoted their hydrolysis from sugar residues, resulting in changes in the phenolic profile and higher antioxidant activity. The results indicated that the optimum condition for hesperetin and naringenin production was 24 h of reaction using β-glucosidase at 20 U g−1. Our results provide a basis for the production of extracts rich in bioactive compounds from CJB, which may be used as food and pharmaceutical applications. [Display omitted] •Flavanones were produced by enzyme treatment of citrus wastes.•Enzyme treatments promoted high bioactive phenolic concentrations in citrus wastes.•Enzymes increased the bioactivity of citrus wastes.•Higher amounts of hesperetin were found after 24 h of enzymatic treatment.•Tannase and β-glucosidase seemed to have a synergistic effect on aglycon production.