Tocopherols are natural bioactive compounds with several health benefits. This study evaluated the effect of different ratios of α- and δ- tocopherol homologs to protect sunflower oil (SO) and olive pomace oil (OPO) against oxidation. A synergistic effect was recorded when the two tocopherols were combined at a ratio of 7:1 (α-T/δ-T). The oil samples were exposed to accelerated oxidation conditions using a Rancimat (90 °C and airflow of 15 L/h for 24 h) and protection from tocopherols was compared with that from butylated hydroxytoluene (BHT). Assessment of oil stability was examined using well-known parameters such as peroxide value (PV), thiobarbituric acid reactive substances (TBARS), p-anisidine value (p-AV), conjugated dienes (CD) and trienes (CT), and total oxidation (Totox) value, which were all significantly reduced when tocopherols were added at a ratio of 7:1 α-T/δ-T. Primary oxidative compounds measured according to PV were only reduced in SO samples (6.11%). Off-flavor compounds measured via TBARS assay in SO samples were reduced by above 20%, while p-AV was also reduced. CDvalue was correlated with PV in SO samples, while the 7:1 mixture was more effective than BHT for CTvalue. Total oxidation values in SO samples and OPO samples were reduced by 6.02% and 12.62%, respectively. These values in SO samples also provided a remarkable correlation (R2 > 0.95) with incubation time. Moreover, the synergistic effect was not only effective in reducing the oxidation values of oil samples, but also in lowering the degradation rate of tocopherols. Protective effects from tocopherols were mainly observed in SO samples, as OPO samples were more resistant to oxidation processes. This effect was even observed in fatty acid analysis, where the 7:1 mixture provided better results than BHT-spiked samples. Thus, it is suggested that tocopherol mixtures might be used as a natural preservative in the food industry to restrain lipid oxidation processes.

Apricot kernels are known to be rich in bioactive compounds such as polyphenols, which have applications in various fields such as cosmetology and the food industry. However, the extraction of these compounds has not been extensively studied. In this study, we aimed to extract oil from apricot kernels and investigate its composition and antioxidant properties. Samples from two years of apricot cannery by-products were used in the study. We employed a common extraction procedure using hexane as a solvent, followed by an analysis of the oil’s fatty acid composition and determination of its antioxidant properties using several methods. Our results indicated that the oil extracted from apricot kernels is rich in oleic and palmitoleic acids, which exhibit health benefits. As regards the volatile compounds of the oil, 2-methyl propanal, benzaldehyde, and benzyl alcohol were detected as the main compounds. Benzaldehyde was also found to be the main component of the essential oil of the kernel. Furthermore, the oil exhibited low antioxidant activity, as demonstrated by its ability to scavenge free radicals. Overall, our findings suggest that apricot kernels are a valuable source of oil with potential applications in the food and cosmetic industries.

The interest in extracting bioactive compounds from food processing waste is growing unabated. Apricots are widely consumed worldwide, and many tons of waste are produced annually. Therefore, apricot pulp waste (APW) may serve as a rich source of bioactive compounds. In the present study, we investigated the extraction of antioxidant polyphenols and carotenoid pigments from APW. In both cases, a response surface methodology was employed, so as to optimize the extraction parameters. As regards polyphenols, it was found that optimum extraction yield (i.e., 28.6 mg gallic acid equivalents per g of dry weight) was achieved using a deep eutectic solvent (comprised of glycerol, citric acid, and L-proline at a molar ratio of 2:1:1), a liquid-to-solid ratio of 100 mL/g, and heating at 80 °C for 155 min. Similarly, optimum extraction of carotenoids (171.2 mg β-carotene equivalents per 100 g of dry weight) was achieved by extracting APW with an n-hexane: acetone: ethanol (2:1:1, v/v/v) mixture at 47 °C for 60 min. The proposed methods were highly efficient and can serve as an alternative to conventional methods employed to date.

Apricots are one of the most important fruits in the Mediterranean region for both their nutritional and economic value. They are widely cultivated and consumed fresh or dried or are used in the food industry for the production of jams, juices, etc. In any case, the seeds they contain constitute waste. The kernels are very rich in bioactive compounds such as polyphenols, a fact that makes them very appealing in cosmetology. However, the extraction of the bioactive compounds of apricot kernels is poorly examined. In this study, the preparation of polyphenol-rich extracts from apricot kernel biomass is discussed. To this end, a common extraction procedure with water as a solvent was employed. To enhance the extraction yield, the use of a deep eutectic solvent (DES) was examined. In addition, the use of pulsed electric field (PEF) either as a standalone extraction method or as a complementary step was also examined. According to the results, it was evident that when PEF was applied before the extraction procedure, an increase of 88% in the total polyphenol content (TPC) was recorded. Likewise, the use of a glycerol:choline chloride (2:1, w/w) DES increased the TPC by ~70%. When the two approaches were combined, a 173% increase was recorded. According to the above, it can be concluded that apricot kernel biomass is a very good source of polyphenols, especially using the proposed extraction procedure.

Lentils are known to be an integral part of a nutritionally balanced diet. Their sprouts are considered even more nutritional since they contain phytonutrients that confer health benefits. As such, incorporating them into a human diet can be advantageous. In this study, seeds from brown and black lentils were germinated aiming to study the changes in their nutritional value after they were grown for different amount of days to different lengths. Since the sprouts can be consumed at various stages of their growth, four growth stages were studied. For each stage, three batches were grown, and one sample of each batch was randomly picked and analyzed in triplicates. The sprouts were examined for their nutritional value. To this end, their content of proteins and carbohydrates was determined, as well as their content in carotenoids and vitamin C. Moreover, emphasis was placed on the phytochemical compounds contained in the sprouts. As results indicate, lentil sprouts not only exhibit high nutritional value but they are also rich in antioxidant compounds. More specifically, an increase of up to 18.8% in the protein content was recorded for 15 cm length sprouts (compared to lentil seeds), accompanied by a decrease in the carbohydrate content of up to 68.9%. Carotenoids and vitamin C content increased up to 224% and 389%, respectively. Additionally, a 34% increase in the polyphenol content was recorded. Moreover, a direct correlation between sprout length and nutritional value was observed, using principal component analysis (PCA) and multivariate correlation analysis (MCA).