Comparison of different Brazilian citrus by-products as source of natural antioxidants

Abstract

Significant amounts of citrus by-products remain after juice processing, which is then used to obtain pectin. The pectin industry then generates a new waste. No study has characterized this residue or suggested applications for it. The main goal of this study was to compare citrus industrial by-products that remain after juice (CJB) and pectin (CPB) extraction, aiming to obtain bioactive compounds. The residues were evaluated for their chemical composition, antioxidant capacity, and polyphenols content. CJB had 2-fold higher total phenols than CPB. Moreover, CJB exhibited higher antioxidant capacity than CPB. Nine polyphenols were detected; hesperidin was the main compound on both residues. CPB had higher content of polyphenols than CJB, which can be attributed to the industry procedure of pectin extraction. Thus, this study provides support for the reuse of CPB to obtain nutraceutical compounds, converting waste into added-value products.

Quality, Bioactive Compounds and Antioxidant Activity During Maturation of Oranges Produced in the Borborema Territory

“…According to Ferreira, Silva and Nunes (2018), the high antioxidant activity of citrus peel extracts may be explained by their phenolic composition, such as hesperidin, naringin, rutin, and caffeic and chlorogenic acids. As mentioned by Bilgiçli, Aktaş and Levent (2014);and Liew et al (2018), the bioactive phytochemicals present in the citrus peel can be exploited for various applications, such as the extraction of natural antioxidants, food additives and dyes for the food industry. These antioxidants act to protect against the accumulation of reactive oxygen species, eliminating them from the system through irreversible dehydrogenation.…”

“…The albedo of 'Mimo-do-Céu' had a comparatively lower EC 50 value (1700.74 g pulp g DPPH -1 ) and, consequently, higher antioxidant activity at the C3 stage. From literature studies, the residues of the citrus agroindustry contained TAA values of 11035 μM TE g -1 (BARBOSA; RUVIARO; MACEDO, 2018), and 9188 μM TE g -1 (MADEIRA JR; MACEDO, 2015) whereas, in citrus peels, the DPPH • radical scavenging activity ranged from 8.35 to 18.20 mg TE g -1 (LIEW et al, 2018), depending on the extraction technique. These differences may be a result of the different analytical protocols of the extraction method, production region, cultivar and maturation stage (FERREIRA; SILVA; NUNES, 2018).…”

“…The antioxidant activity in orange depends on the cultivar and maturity stage of the fruit. In addition, the change in antioxidant activity is related to the metabolism of polyphenols, ascorbic acid, flavonoids and carotenoids (BARBOSA; RUVIARO; MACEDO, 2018;WANG et al, 2016). As Zou et al (2016) stated, pre-/postharvest and processing factors influence the chemical structure and antioxidant capacity of citrus fruits.…”

“…Certain water-soluble fibers, such as pectin, reduce the postprandial serum-cholesterol and the blood glucose in humans. Insoluble fibers (lignin, cellulose and some hemicelluloses) serve almost exclusively as bulking agents that promote less intestinal transit time and increase the fecal mass, thereby improving the efficiency of the intestine and colon, and reducing the risk of colorectal cancer (BILGIÇLI; AKTAŞ; LEVENT, 2014).…”

Diversity and Biotechnological Potential of Xylan-Degrading Microorganisms from Orange Juice Processing Waste

“…On the other hand, orange juice processing waste consists of high levels of lignin, cellulose and hemicellulose, which has been reported to be equal to 40% of the dry weight [3]. A range of biotechnological applications have recently been proposed for the valorization of orange juice processing waste, including the recovery of high added-value products like natural antioxidants, essential oils and pectin [4,5], the manufacturing of absorbent material [6] and the production of bioethanol and biomethane [7][8][9]. Regarding enzyme technology, the use of citrus processing waste as bioresource for cellulases and pectinases has also been explored [10] for potential applications in food technology, solid-state fermentation and energy recovery [11,12].…”