Optimization of Antioxidant Compounds Extraction from Fruit By-Products: Apple Pomace, Orange and Banana Peel

Abstract

The aim of this research was to optimize, by response surface methodology, antioxidant compounds extraction from apple pomace, orange and banana peel. The extracts were obtained at different temperatures and times. All by‐products show a good content of vitamin C (12–102 mg of ascorbic acid/100 g dw), flavonoids (455–756 mg of catechin/100 g dw), phenolic compounds (227–689 mg of gallic acid equivalent/100 g dw), antioxidant capacity by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH; 454–1,040 mg of Trolox/100 g dw) and ferric‐reducing antioxidant power (FRAP; 4–32 mM Fe2+/100 g dw) assays. Polynomial models obtained from each by‐product showed a good fitting (0.81–0.97). Temperatures of 41–60C promote the major extraction of bioactive compounds and antioxidant capacity from apple pomace. In orange peel, the optimum condition for vitamin C extraction was 20C (0.5 h); flavonoids, total phenols and antioxidant capacity (DPPH) were mostly extracted at 60C. In banana peel, the optimization indicates that major flavonoid concentration and antioxidant capacity (DPPH and FRAP assays) were at 60C (0.5 h). Practical Applications By‐products are a good source of bioactive compounds that could be used to obtain products with added value; in this sense, the optimization of extraction of bioactive compounds with antioxidant capacity may be an important step in order to obtain the major concentration of antioxidant compounds with the less use of energy and cost. Therefore, the information presented in this study may be a good tool to apply in the industrial extraction of bioactive compounds from apple pomace, orange and banana peel.

Effect of solvents and extraction methods on total anthocyanins, phenolic compounds and antioxidant capacity of Renealmia alpinia (Rottb.) Maas peel

“…Moreover, some mixtures significantly (p < 0.05) affected the extraction of phenolic compounds (ethanol-methanol) and total anthocyanins (ethanol-methanol and ethanolacetone) from x´kijit peel, as well as its antioxidant capacity (ethanol-methanol, methanol-acetone and ternary mixture). Figure 2 shows the correlation between experimental and predicted data of x´kijit peel extracts, when a high correlation was observed in total anthocyanins, phenolic compounds and antioxidant capacity; correlation values between data is necessary to apply models and evaluate the effect of different factors in bioactive compounds extraction and antioxidant capacity from any sample (Hernández-Carranza et al 2016). According to the models, absolute methanol was the solvent used for the evaluation of traditional and novel extraction methods.…”

“…Either traditional (maceration, agitation, Soxhlet, hydrodistillation) or novel (enzyme, microwave, ultrasound-assisted, using supercritical fluids) extraction processes have been reported (Corrales et al 2008;Ghafoor et al 2011). A number of factors including extraction time, temperature, pressure, type of solvent, solid-to-solvent ratio, among others might affect the process efficiency (Hernández-Carranza et al 2016). Under selected conditions, some novel processes could allow reducing extraction time and temperature and/or increasing extract yield and quality, while decreasing solvent usage when compared to other conventional extraction methods such as Soxhlet (Wang & Weller 2006;Azmir et al 2013).…”

“…In order to evaluate the effect of combined methods on the efficiency of the extraction process, several combinations were implemented, all using a 5-min ultrasound pretreatment coupled with: (a) 1-h stirring; (b) 6-h stirring; (c) 2-h Soxhlet, and (d) 4-h Soxhlet. All extraction processes were done in triplicate and independently of the method used, all the extracts obtained were cotton-filtered and immediately used for evaluating total anthocyanins, phenolic compounds, and antioxidant capacity (Hernández-Carranza et al 2016).…”

Quantification of Flavonoids in Brazilian Orange Peels and Industrial Orange Juice Processing Wastes

“…Orange peels are a good source of flavonoids such as glycosides and polymethoxylated flavones [11]. Orange peel extracts of different citrus varieties were prepared in methanol, hexane and DMSO.…”

“…These compounds are present in many sources, including citrus fruits [7] [8] [9] [10] [11]. The therapeutic or even toxic activity, e.g., antioxidant, anti-inflammatory, antibacterial, antimutagenic, antiviral and antimetastatic effects, has been reported in a great number of these flavonoids [12] [13] [14] [15].…”