Improved Hydrotropic Extraction of Carnosic Acid from Rosemary and Sage with Short-Chain Monoalkyl Glycerol Ethers

Abstract

Hydrotropic extraction in water with biobased amphiphiles is considered as an interesting alternative to conventional extraction with organic solvents. In this study, butyl, isoamyl, and pentyl glycerol ethers (C4Gly, iC5Gly, and C5Gly, respectively) are investigated for the extraction from rosemary (Rosmarinus officinalis) and sage (Salvia officinalis) of carnosic acid (CA), a powerful natural antioxidant used as an alternative to synthetic ones in food and cosmetic industries. First, interactions between CA and hydrotropes are studied to set the extraction conditions, resulting in the measurement of the solubility curves and miscibility of CA in the hydrotropic solutions. Then, C5Gly is shown to have the highest efficiency to extract CA, which is rationalized with a molecular model previously established for an alkyl polyethylene glycol ether (C i E j ) series of amphiphiles based on their log P and molecular volume. Additionally, measurement of the contact angles of the hydrotropic solutions on rosemary leaves indicates that the efficiency of the hydrotrope is also dependent on the interfacial tension.

Cascade Release of Payloads from Polymer Nanofibers with Conjugated Hydrotropes and Kosmotropes

“…To overcome this issue, chemicals such as surfactants, hydrotropes, and kosmotropes can be added for increasing the solubility of hydrophobic substances in pharmaceutical science, − biomedicine, − catalytic, , cosmetic science, − and anticorrosion , applications. Whereas surfactants can lead to uncontrollable aggregation characteristics and may have strong detrimental interactions with cells membranes, hydrotropes and kosmotropes were used as environmentally responsible molecules for increasing the water solubility of payloads. − ,,,− ,− The agents are typically characterized by an amphiphilic molecular structure. However, they are distinguished from surfactants due to deficiency of the hydrophobic part to produce well-organized self-associated aggregates such as micelles .…”

“…A limitation is that payloads after cleavage of the acid-responsive linkages can present low solubility in water. − Indeed, over 60% of hydrophobic substances currently exploited in the pharmaceutical industry encounter a reduction of therapeutic efficacy due to limited aqueous solubility . To overcome this issue, chemicals such as surfactants, hydrotropes, and kosmotropes can be added for increasing the solubility of hydrophobic substances in pharmaceutical science, − biomedicine, − catalytic, , cosmetic science, − and anticorrosion , applications. Whereas surfactants can lead to uncontrollable aggregation characteristics and may have strong detrimental interactions with cells membranes, hydrotropes and kosmotropes were used as environmentally responsible molecules for increasing the water solubility of payloads. − ,,,− ,− The agents are typically characterized by an amphiphilic molecular structure.…”

Selective Extraction of Antioxidants by Formation of a Deep Eutectic Mixture through Mechanical Mixing

“…Alcoholic solvents are commonly used to extract phenolics as well as acetone, ethyl acetate, and other volatile organic solvents. However, efforts have been recently made to shift from these solvents to more sustainable alternatives with less toxicity and better eco-environmental friendness. , …”