Sustainable Development and Storage Stability of Orange By-Products Extract Using Natural Deep Eutectic Solvents

Abstract

The citrus industry produces large amounts of waste rich in bioactive compounds that have important effects on human health. Their extraction was performed using organic solvents, and a greener alternative to those solvents are natural deep eutectic solvents (NADES). The present study aimed to obtain and optimize extracts rich in polyphenols and flavonoids from orange peels using NADES and monitor polyphenol stability in the extracts for 30 days. The software COSMOtherm (conductor-like screening model) was used to screen fourteen NADES. The most promising solvents were lactic acid:glucose (LA:Glu) with an extraction yield of 1932 ± 7.83 mgGAE/100 gdw for TPC (total polyphenol content) and 82.7 ± 3.0 mg/100 gdw for TFC (total flavonoid content) and in the case of L-proline:malic acid (LP:MA) was 2164 ± 5.17 mgGAE/100 gdw for TPC and 97.0 ± 1.65 mg/100 gdw for TFC. The extraction process using LA:Glu and LP:MA was optimized, and the results showed that the selected variables (%NADES, solid:liquid ratio, and extraction time) had a significant influence on the extraction of TPC and TFC. Results showed that NADES improve the stability of TPC. These findings revealed that NADES are efficient for the extraction of bioactive compounds from orange by-products, and these extracts can represent an alternative for the food industry to enrich food products with natural ingredients.

Natural deep eutectic solvents characteristics determine their extracting and protective power on chlorogenic acids from sunflower meal

“…In this case, however, the result obtained with NaDES was still superior to the ethanolic and aqueous extracts tested [21]. In the extraction of phenolic compounds from orange peel, there was no signi cant difference between NaDES composed of lactic acid:glucose (LA:G), L-proline:malic acid and 50% ethanol [22]. The extraction of chlorogenic acid from Artemisiae scopariae was studied by Yue et al (2021), two formulations stood out when compared to ethanol and water, sorbitol:choline chloride and lactic acid:glucose (LA:G).…”

“…Urios et al (2022) the phenolic compounds from orange by-products in formulations containing lactic acid showed better upkeep at lower temperatures (4ºC > 25ºC). Phenolic compounds extracted from co-products of olive, onion, tomato and pear seeds with lactic acid:glucose (AL:G) remained stable for two months at -18°C and 4°C, but there was a loss of 90% of apigenin and quercetin in the aqueous extract in the same conditions[28].…”

Valorization of artichoke outer petals by using ultrasound‐assisted extraction and natural deep eutectic solvents (NADES) for the recovery of phenolic compounds

“…Indeed, the polarity of NADES consists of organic acids is higher than sugar or polyol based NADES as well as even water. This physicochemical attribute refers to formation of hydrogen bond and greater dissolving capacity of hydrosoluble phytochemicals 30,31 . A study conducted by Gomez‐Urios et al 30 .…”

“…This physicochemical attribute refers to formation of hydrogen bond and greater dissolving capacity of hydrosoluble phytochemicals. 30,31 A study conducted by Gomez-Urios et al 30 demonstrated that orange peel extracts prepared by ChCl based NADES, including malic acid or glycerol, comprised more bioactive compounds (4-hydroxybenzoic, vanillic acid, chlorogenic acid, ferulic acid, catechin, p-coumaric acid and caffeic acid) than that of ethanol, suggesting a high affinity between those bioactives and selected NADES mixtures. In another study, phenolic profiles and their levels in the date palm seed extracts were investigated by comparing the findings obtained from ChCl:La or conventional ones (80% ethanol or 80% methanol) used as solvent.…”

Extraction Systems and Analytical Techniques for Food Phenolic Compounds: A Review

“…H-bonding interactions are responsible for the high extractability of DES [ 72 ]. Of special interest are natural DES or NADES, which can even be present in food products without further purification of the extracts if they are, for example, safe for consumption and their use is approved by food safety administrations [ 73 ]. The properties of the DES solution can be modulated by changing its composition (compounds mixed and ratio) to increase the efficiency of the extraction of phenolic compounds, both free and bound ones [ 74 ].…”