Enzyme-Assisted Extraction of Carotenoids and Phenolic Derivatives from Tomatoes

Abstract

According to biorefinery and “green chemistry” concepts, we investigated here new procedures to recover carotenoids and phenolics from tomato tissue, by an enzyme-assisted extraction using comparatively commercial and crude pectinases and cellulases obtained from fermented fractions of Penicillium oxalicum and Trichoderma reesei, respectively. Different ratios between the enzyme activity and substrate (1, 5 and 10%) were used when incubated with the tomato homogenate. Carotenoids released by enzyme treatment were identified and quantified by HPLC-DAD, while phenolic derivatives were quantified by UV-Vis spectrometry. The antioxidant activity was measured by DPPH method and correlated with the release of bioactive molecules. The enzyme-assisted extraction of carotenoids increased the lycopene recovery after cellulases treatment 1.6 times while for I²-carotene 2.4 times, comparatively with the untreated samples. The increase of lycopene and I²-carotene release after pectinases treatment was lower. Higher yields of phenolic derivatives were found using 10% crude pectinase, increasing the extraction up to 174.6 mg GAE/100g fresh weight. The antioxidant activity, based on DPPH scavenging was significantly higher than for control, suggesting that enzyme-assisted methods not only increase the yield of photochemicals recovery but also improve the antioxidant capacity of resulted extracts. Generally the crude enriched fractions in enzymes were more active than commercial ones. Beside the enhancement of release yield, the use of crude enzymes prevents the use of high quantities of organic solvents and assures the increase of antioxidant capacity of such hydrolysed extracts. Carotenoids were better released by cellulases while phenolic derivatives were better released from the pectin matrix, by crude pectinases. Due to the low production costs for crude enzymes, the release of bioactive molecules such as carotenoids and phenolics from plant tissues by enzyme-assisted hydrolysis is a good biotechnological solution.