Since solvents of petroleum origin are now strictly regulated worldwide, there is a growing demand for using greener, bio-based and renewable solvents for extraction, purification and formulation of natural and food products. The ideal alternative solvents are non-volatile organic compounds (VOCs) that have high dissolving power and flash point, together with low toxicity and less environmental impact. They should be obtained from renewable resources at a reasonable price and be easy to recycle. Based on the principles of Green Chemistry and Green Engineering, vegetable oils could become an ideal alternative solvent to extract compounds for purification, enrichment, or even pollution remediation. This review presents an overview of vegetable oils as solvents enriched with various bioactive compounds from natural resources, as well as the relationship between dissolving power of non-polar and polar bioactive components with the function of fatty acids and/or lipid classes in vegetable oils, and other minor components. A focus on simulation of solvent-solute interactions and a discussion of polar paradox theory propose a mechanism explaining the phenomena of dissolving polar and non-polar bioactive components in vegetable oils as green solvents with variable polarity.

The present study was designed to evaluate five green solvents, i.e. 2-methyltetrahydrofuran (2-MeTHF), dimethyl carbonate (DMC), cyclopentyl methyl ether (CPME), isopropyl alcohol (IPA) and ethyl acetate, for the substitution of n-hexane in the extraction of carotenoids from carrots. Initially, solvent selection was made through the theoretical physicochemical solvent properties and solubility results obtained using two simulation programs, Hansen Solubility Parameters (HSPs) and Conductor-like Screening Model for Realistic Solvation (COSMO-RS) which use a statistical thermodynamics approach based on the result of quantum chemical calculation, for comprehension of the dissolving mechanism. On the basis of the HSPs analysis, non-polar or slightly polar solvents were the most suitable solvents for extraction of carotenoids. COSMO-RS analysis showed a higher probability of solubility for all the carotenoids from carrot in CPME, 2-MeTHF and ethyl acetate compared with n-hexane. The experimental results using a conventional solid–liquid extraction by maceration showed that the best green solvents were CPME, 2-MeTHF and ethyl acetate in accordance with the predictive results from COSMO-RS. The highest carotenoid content (78.4 mg 100 g⁻¹ DM) was observed in CPME where 66% was represented by β-carotene and 34% was α-carotene. These results support the potential of CPME and 2-MeTHF as alternative green solvents for extraction of carotenoids.

The present review compiles positive MS fragmentation data of selected carotenoids obtained using various ionization techniques and matrices. In addition, new experimental data from the analysis of carotenoids in transgenic maize and rice callus are provided. Several carotenes and oxygen‐functionalized carotenoids containing epoxy, hydroxyl, and ketone groups were ionized by atmospheric pressure chemical ionization (APCI)‐tandem mass spectrometry (MS/MS) in positive ion mode. Thus, on the basis of the information obtained from the literature and our own experiments, we identified characteristic carotenoid ions that can be associated to functional groups in the structures of these compounds. In addition, pigments with a very similar structure were differentiated through comparison of the intensities of their fragments. The data provide a basis for the structural elucidation of carotenoids by mass spectrometry (MS). © 2013 Wiley Periodicals, Inc. Mass Spec Rev 33: 353–372, 2014

S. MARIN, V. SANCHIS, I. VINAS, R. CANELA AND N. MAGAN. 1995. The effect of different water activities (a_w, 0.968, 0.956, 0.944, 0.925) and temperature (25°C and 30°C) on colonization and production of fumonisin B₁ (FB₁) and B₂ (FB₂) on sterile layers of maize by Fusarium proliferatum and F. moniliforme isolates was determined over periods of 6 weeks. Generally, both F. moniliforme and F. proliferatum grew faster with increasing a_w and best at 30°C. All three isolates produced more FB1 than FB₂ regardless of a_w or temperature. Very little FB₁ and FB₂ were produced at 0.925 a_w, with maximum produced at 0.956 and 0.968 a_w at both temperatures tested. Most FB₁ and FB₂ were produced by F. moniliforme (25N), followed by F. proliferatum isolates (73N and 131N). At all a_w levels and both temperatures there was an increase in FB₁ and FB₂ concentration with time. Statistical analyses of a_w, temperature, time, two- and three-way interactions showed some significant differences between isolates and FB₁ and FB₂ production.