Recovery of bioactive anthocyanin pigments from Ficus carica L. peel by heat, microwave, and ultrasound based extraction techniques

Abstract

Due to its coloration, the fig (Ficus carica L.) peel, a by-product of fruit processing and/or consumption, is a potential source of anthocyanin compounds. In the present study different extraction techniques (heat, ultrasound, and microwave) were compared aiming to recover the anthocyanin pigments and optimize its extraction conditions. A response surface methodology tool with three factors and five levels for each factor was used according to a circumscribed central composite design. The variables tested for the heat and microwave extraction methods were time, temperature, and solvent proportion (ethanol/water ratio), meanwhile, for the ultrasound method, the variables tested were the ultrasonic power, time, and solvent proportion. The anthocyanin composition of the extract was determined by HPLC-DAD-ESI/MS, and the used criteria responses were: i) quantification of cyanidin 3-rutinoside (C) in the extracted residue (mg C/g R) and in the dried peel (mg C/g P dw), and the extraction yield of the obtained residue (g R/g P dw). Ultrasound extraction was the most effective method, yielding 3.82 mg C/g R at the optimal global extraction conditions (21 min, 310 W, and 100% of ethanol). Additionally, the solid-to-liquid ratio effect was studied at the optimal conditions, using a dose-response format, in view of its plausible transference to industrial level. For the ultrasound method, an increased non-linear relationship was observed for concentrations in the range 5 to 200 g/L, being the optimal solution close to 150 g/L. In brief, the obtained results show the potential of fig peels as a source of anthocyanin pigments, with potential uses in various industrial fields, such as food, pharmaceutical, and cosmetic.

Bioactive compounds content and antimicrobial activities of wild edible Asteraceae species of the Mediterranean flora under commercial cultivation conditions

“…Asteraceae family includes numerous wild edible species that are native in the Mediterranean basin, most of which are consumed for their fresh and tender leaves as salad vegetables (Petropoulos, Ntatsi, Levizou, Barros, & Ferreira, 2016) or as vegetable mixtures (Guarrera & Savo, 2016). Chemical composition of native species has gained great research interest during the last decades, due to increased demands from the food industry and consumers for healthy and functional foods, rich in bioactive compounds (Albuquerque et al, 2018;Backes et al, 2018;Giacometti et al, 2018). Many of the reported studies refer to polyphenols, sesquiterpenes, and organic and fatty acids composition which have been associated with positive effects against cardiovascular diseases, cancer, oxidative stress and other diseases (Morales et al, , 2014Simopoulos, 2004).…”

Extraction of Antioxidants from Blackberry (Rubus ulmifolius L.): Comparison between Ultrasound- and Microwave-Assisted Extraction Techniques

“…On the contrary, the latter largely reduce solvent volume demand, energy consumption, and processing length of time [11,12]. Over the last decade two advanced techniques such as UAE and MAE have been recognized as promising green extraction technologies [13]. UAE is an emerging powerful alternative to traditional methods for the extraction of antioxidant compounds from fruit [13][14][15][16].…”

“…Over the last decade two advanced techniques such as UAE and MAE have been recognized as promising green extraction technologies [13]. UAE is an emerging powerful alternative to traditional methods for the extraction of antioxidant compounds from fruit [13][14][15][16]. Simple, economic, fast, low solvent consumption, improved method, and better extraction quality are the advantages that make it an effective and greener method for quality control [17].…”

“…Since UAE is influenced by many factors including mainly solvent, temperature, amplitude, cycle, pH, and sample:solvent ratio, and MAE is mainly affected by solvent, temperature, pH, and sample:solvent ratio, they cannot be applied to every type of matrices, so it is necessary to determine their respective optimum extraction conditions [13]. Response surface methodology (RSM) is a suitable statistical tool that allows the optimization of multiple variables and their interactions while minimizing the number of experiments [28,29].…”

Specific Energy: A New Approach to Ultrasound-assisted Extraction of Natural Colorants

“…Backes, Pereira, Barros, Prieto, Genena, Barreiro and Ferreira [38] observed that the relation of S/F is extremely important to obtain a pure extract of anthocyanin pigments from Ficus carica. Out of the values of S/F studied, the of 5 obtained the best results.…”