Optimization of clean extraction methods to isolate carotenoids from the microalga Neochloris oleoabundans and subsequent chemical characterization using liquid chromatography tandem mass spectrometry

Abstract

A novel experimental design was used to optimize the extraction of carotenoids from Neochloris oleoabundans using pressurized liquid extraction with food-grade solvents such as ethanol and limonene. Experimental factors, including the extraction temperature and the solvent composition, were optimized using a three-level factorial design. The response variables extraction yield and total amount of carotenoids were assessed. The statistical analysis of the results provided mathematical models to predict the behavior of the responses as a function of the factors involved in the process. The optimum conditions predicted by the model developed in this study were 112 °C as the extraction temperature and 100% ethanol as the extraction solvent. Chemical characterization of the extracts obtained was performed by means of high-performance liquid chromatography-tandem mass spectrometry. The results obtained demonstrated that, under certain growth conditions (photoautotrophically cultured in a medium supplemented with 0.3 g L(-1) KNO3), N. oleoabundans accumulated significant total amounts of the carotenoids (from 57.4 to 120.2 mg carotenoids per gram of extract depending on the extraction conditions), mainly lutein, cantaxanthin, zeaxanthin, and astaxanthin monoesters and diesters.

Pressurized liquid extraction of Neochloris oleoabundans for the recovery of bioactive carotenoids with anti-proliferative activity against human colon cancer cells

“…PLE extractions of pre-treated samples were performed using an accelerated solvent extractor (ASE 200, Dionex, Sunnyvale, CA, USA). Extractions were carried out using ethanol as solvent at 100°C and 20 min as static extraction time, as suggested in Castro-Puyana et al (2013). An extraction cell heating-up was applied during 5 min prior to each extraction (time fixed by the system).…”

Assessment of nutritional and metabolic profiles of pea shoots: The new ready-to-eat baby-leaf vegetable

“…From the obtained UV-vis spectra information it was possible to identify 26 compounds, corresponding 12 to carotenoids and the other to chlorophyll a and b and their deriva-tives. A tentative identification of the six main separated carotenoid compounds was accomplished by comparing the UV-vis and MS spectra information provided by the two detectors (i.e., DAD and MS) with commercial standards and data from the literature (Britton, Liaaen-Jensen, & Pfander, 2004;Castro-Puyana et al, 2013;Crupi, Milella, & Antonacci, 2010). Information about characteristic UV-Vis spectra, [M + H] + , and the main fragments obtained by MS 2 experiments for the different carotenoids is presented in Table 3, together with their quantification in the two sampling days.…”

The use of environmentally sustainable bio-derived solvents in solvent extraction applications—A review

“…Extraction of lipids from olives using limonene provided similar results to n-hexane [60] , as did the extraction of lipids from marine microalgae by pressurized limonene [77] . However, in the extraction of carotenoid from tomatos, extraction yields by limonene is lower than that of extraction by ethanol [78] although still higher than that of extraction by hexane and comparable with that of extraction by dichloromethane [11] . The higher extraction yield of ethanol is attributed to its higher polarity.…”