This study explores the interaction of saponification products with microbial communities in aerobic and anaerobic sewage sludge from wastewater treatment plants (WWTPs). It focuses on the reutilisation of waste cooking oils into soap and evaluates the biodegradation of these products using microbial respiration activity and biological oxygen demand (BOD) as indicators. Results demonstrate that soaps degrade effectively under both aerobic and anaerobic conditions, with anaerobic degradation contributing to methane production-a valuable biofuel. Importantly, no toxic effects on sludge microorganisms were observed. The research highlights that these saponification products can be fully integrated into the wastewater treatment process without adverse effects on microbial dynamics. Moreover, the economic analysis reveals that biosurfactants derived from used oils can be produced at a cost of approximately 0.12-3.0 EUR/kg, significantly lower than the 1-20 EUR/kg typically spent on chemical coagulants or synthetic surfactants used in WWTPs. These findings support the feasibility of repurposing waste oils into environmentally friendly, cost-effective treatment additives, enhancing microbial performance and promoting circular economy practices in wastewater management.

• Keywords
• edible oil waste, microorganism respiration, sustainability, wastewater treatment efficiency,
• MeSH
• Aerobiosis MeSH
• Anaerobiosis MeSH
• Bacteria metabolism   MeSH
• Biodegradation, Environmental MeSH
• Water Purification * methods   MeSH
• Biological Oxygen Demand Analysis MeSH
• Soaps metabolism   MeSH
• Waste Disposal, Fluid * methods   MeSH
• Wastewater * microbiology   chemistry   MeSH
• Sewage * microbiology   MeSH
• Surface-Active Agents metabolism   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Soaps MeSH
• Wastewater * MeSH
• Sewage * MeSH
• Surface-Active Agents MeSH

This study assessed the potential of dried Cayenne pepper (CP; Capsicum annuum L.) as a natural additive to rice bran oil (RBO), grape seed oil (GSO), and virgin olive oil (OO). Key analyses included peroxide and acid values, oxidative stability (Rancimat method), the composition of fatty acids (FAs) (GC-FID method), antioxidant activity (AA; DPPH method), and antimicrobial properties (disc diffusion method). Capsaicin and the dihydrocapsaicin contents in CP were quantified (HPLC-DAD method) as 1499.37 ± 3.64 and 1449.04 ± 5.14 mg/kg DW, respectively. Oleic acid (C18:1cis n9) dominated in OO (69.70%), OO-CP (69.73%), and RBO-CP (38.97%), while linoleic acid (C18:2cis n6) prevailed in RBO (41.34%), GSO (57.93%), and GSO-CP (58.03%). The addition of CP influenced the FA profile, particularly linoleic acid in OO and RBO, and all FAs in GSO. Peroxide and acid values increased significantly in RBO and GSO upon CP addition, but induction times remained unaffected. The strongest AA (77.00 ± 0.13%) was observed in OO-CP. Cayenne pepper significantly enhanced the antioxidant profiles of all oils compared to the counterparts. However, the antimicrobial activity was weak (≤5.0 mm inhibition zones) against tested microorganisms. These findings support CP as a functional additive for enhancing the nutritional and functional properties of gourmet oils, while highlighting the need for further optimization to improve stability and bioactivity.

• Keywords
• Cayenne pepper red, antimicrobial activity, antioxidant activity, fatty acids, health benefits, technological profile, vegetable oils,
• MeSH
• Anti-Infective Agents pharmacology   chemistry   MeSH
• Antioxidants chemistry   pharmacology   MeSH
• Capsicum * chemistry   MeSH
• Capsaicin analogs & derivatives   chemistry   MeSH
• Fatty Acids chemistry   analysis   MeSH
• Plant Oils * chemistry   pharmacology   MeSH
• Olive Oil chemistry   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Anti-Infective Agents MeSH
• Antioxidants MeSH
• Capsaicin MeSH
• Fatty Acids MeSH
• Plant Oils * MeSH
• Olive Oil MeSH

The paper is focused on the epoxidation of methyl esters prepared from oil crops with various profiles of higher fatty acids, especially unsaturated, which are mainly contained in the non-edible linseed and Camelina sativa oil (second generation). The novelty consists in the separation and identification of all products with oxirane ring formed through a reaction and in the determination of time course. Through the epoxidation, many intermediates and final products were formed, i.e., epoxides with different number and/or different position of oxirane rings in carbon chain. For the determination, three main methods (infrared spectroscopy, high-pressure liquid chromatography and gas chromatography with mass spectrometry) were applied. Only gas chromatography enables the separation of individual epoxides, which were identified on the base of the mass spectra, molecule ion and time course of products. The determination of intermediates enables: (i) control of the epoxidation process, (ii) determination of the mixture of epoxides in detail and so the calculation of selectivity of each product. Therefore, the epoxidation will be more environmentally friendly especially for advanced applications of non-edible oil crops containing high amounts of unsaturated fatty acids.

• Keywords
• epoxidation, esters, gas chromatography, infrared spectroscopy, liquid chromatography, vegetable oils,
• MeSH
• Epoxy Compounds chemistry   MeSH
• Esters * analysis   MeSH
• Fatty Acids chemistry   MeSH
• Fatty Acids, Unsaturated * chemistry   MeSH
• Plant Oils chemistry   MeSH
• Gas Chromatography-Mass Spectrometry methods   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Epoxy Compounds MeSH
• Esters * MeSH
• Fatty Acids MeSH
• Fatty Acids, Unsaturated * MeSH
• Plant Oils MeSH

Ferns are part of the diet and traditional medicine in East Asia, North America, and Oceania, however, their importance has been forgotten in Europe. Here, the nutritional and antioxidant potential of young fern fronds (fiddleheads) of eight families were studied. Most of the tested fern species excelled in high antioxidant capacity when compared to the reference leafy vegetables spinach and rocket. On average, the total phenol content reached 220 mg·g-1 of extract dry weight for all fiddleheads, and 15 out of 24 tested species exceeded 1 g Trolox equivalent per gram of extract dry weight in Oxygen Radical Absorbance Capacity (ORAC) assay. On the other hand, fiddleheads contained a comparable amount of carotenoids and ascorbic acid with the reference vegetables. In the case of fatty acid composition, fiddleheads contained especially high amounts of essential omega-3 (n3) and omega-6 (n6) polyunsaturated fatty acids with a beneficial n6/n3 ratio. The n6/n3 ratio in all tested species was between 2 and 6.4, whereas the ratio in the reference vegetables was below 0.4. All in all, fiddleheads from European ferns are a rich source of valuable antioxidants and essential fatty acids with a desirable n-6/n-3 ratio and may thus form an alternative source of these compounds, especially for those people not consuming fish and fish products.

• Keywords
• alternative vegetable, fatty acid profile, fern species, fiddleheads, natural antioxidants, nutritional quality,
• Publication type
• Journal Article MeSH