The food processing industry is a continuously developing sector that uses innovative technologies to efficiently process food products. During processing, food industries generate substantial amounts of by-products in the form of waste materials. This food waste consists of organic matter rich in bioactive compounds, such as polyphenols, carotenoids, and flavonoids. Improper management of food waste can adversely affect both the environment and human health, leading to environmental pollution and the release of greenhouse gas emissions. Thus, proper food waste management has become an urgent global issue. The presence of bioactive compounds (mainly polyphenols, flavonoids, and anthocyanins, but also carotenoids, alkaloids, proteins, lipids, and carbohydrates) in food waste holds the potential to transform them into valuable resources. Several sectors, including food and energy, have recognized food waste as an innovative source. Recently, much emphasis has been placed on optimizing the extraction yield of such bioactive compounds through the utilization of environmentally friendly and sustainable methodologies and solvents. Pulsed electric field (PEF)-assisted extraction is an emerging technique that holds promise for the utilization of waste materials. PEF technology can efficiently optimize the extraction of valuable compounds within a shorter time while minimizing solvent and energy consumption. In this review, we provide a comprehensive overview of the current state of PEF technology and its implications for recovering bioactive compounds from food waste. The integration of innovative technologies like PEF in the food processing industry can play a crucial role in managing food waste sustainably, reducing environmental impact, and harnessing the full potential of bioactive compounds contained in these waste materials. The objective of this critical review is to provide an overview of the utilization of PEF pretreatment for food by-products and to conduct a comparative analysis with other extraction techniques.

Nowadays, more and more researchers engage in studies regarding the extraction of bioactive compounds from natural sources. To this end, plenty of studies have been published on this topic, with the interest in the field growing exponentially. One major aim of such studies is to maximize the extraction yield and, simultaneously, to use procedures that adhere to the principles of green chemistry, as much as possible. It was not until recently that pulsed electric field (PEF) technology has been put to good use to achieve this goal. This new technique exhibits many advantages, compared to other techniques, and they have successfully been reaped for the production of extracts with enhanced concentrations in bioactive compounds. In this advancing field of research, a good understanding of the existing literature is mandatory to develop more advanced concepts in the future. The aim of this review is to provide a thorough discussion of the most important applications of PEF for the enhancement of polyphenols extraction from fresh food products and by-products, as well as to discuss the current limitations and the prospects of the field.

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. CD_value was correlated with PV in SO samples, while the 7:1 mixture was more effective than BHT for CT_value. 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.

Moringa oleifera leaves are rich sources of bioactive compounds with potential health benefits, including antioxidants and anti-inflammatory agents. Pressurized liquid extraction (PLE) stands out as a promising technique for effectively extracting valuable compounds from natural sources. In this study, we aimed to optimize PLE parameters, such as temperature, extraction duration, and pressure, to maximize bioactive compound (polyphenols, flavonoids, and ascorbic acid) yield from M. oleifera leaves and evaluate their antioxidant and anti-inflammatory activities. According to the outcomes of this research, the maximum achieved total polyphenol content was 24.10 mg gallic acid equivalents (GAE)/g of dry weight (dw), and the total flavonoid content was increased up to 19.89 mg rutin equivalents (RtE)/g dw. Moreover, after HPLC-DAD analysis, neochlorogenic and chlorogenic acids, catechin and epicatechin, rutin, and narirutin were identified and quantified. As far as the optimum ascorbic acid content is concerned, it was found to be 4.77 mg/g dw. The antioxidant activity was evaluated by three different methods: ferric reducing antioxidant power (FRAP), the DPPH method, and the anti-hydrogen peroxide activity (AHPA) method, resulting in 124.29 μmol ascorbic acid equivalent (AAE)/g dw, 131.28 μmol AAE/g dw, and 229.38 μmol AAE/g dw values, respectively. Lastly, the albumin denaturation inhibition was found to be 37.54%. These findings underscore the potential of PLE as an efficient extraction method for preparing extracts from M. oleifera leaves with the maximum content of bioactive compounds.

Plant-derived secondary metabolites such as triterpenes and triterpenoids are present in a wide range of plant species. These compounds are particularly attractive due to their extensive range of biological properties and potential applications as intermediates in the synthesis of novel pharmacologically promising medications. Saponins, which are glycosylated triterpenoids found in nature, exhibit the same properties. At this point, the effectiveness of saponins as an anti-inflammatory medication has been verified. This review article examines the primary connections between immune responses and anti-inflammatory activity, focusing specifically on the correlation between triterpenes and triterpenoids. These connections have been investigated in various cell models, as well as in vitro and in vivo studies. The present research provides a comprehensive overview of the current understanding of the therapeutic capabilities of triterpenes and triterpenoids in immune and inflammatory processes. It also highlights emerging standards and their potential utilization in pharmaceutical and clinical settings.

A member of the Verbenaceae family, Aloysia citrodora, or lemon verbena, is a medicinal herb with antioxidant compounds. The aim of this study was to develop a green, optimized method for the bioactive compound (carotenoids, ascorbic acid, and polyphenols) extraction from lemon verbena leaves through response surface methodology (RSM). The bioactive compound recovery was shown to be significantly affected by the extraction technique (both with pulsed electric field and ultrasound-assisted extraction), along with an extraction solvent, based on partial least squares analysis. Consequently, the maximum polyphenol yield required a double-assisted extraction with a relatively low extraction duration (60 min) at a high temperature (80 °C), with a moderate-polarity extraction solvent (50% v/v ethanol). With the optimized method, the total polyphenol content (TPC) was measured at 175.03 mg gallic acid equivalents/g, whereas chromatographic analysis revealed that verbascoside was the most prevalent polyphenol (132.61 mg/g). The optimum extract provided a high antioxidant capacity through the measurements of FRAP (1462.17 μmol ascorbic acid equivalents (AAE)/g), DPPH (1108.91 μmol AAE/g), and H₂O₂ (1662.93 μmol AAE/g). Total carotenoids were measured at 499.61 μg/g, with ascorbic acid at 8.36 μg/g. Correlation analyses revealed a negative correlation of the latter compound with color coordinates. This study highlights the potential of lemon verbena leaves to be used in pharmaceutical and food industries.