INFLUENCE OF PRODUCT TO BE FRIED TYPE ON THE RATE OF THERMAL OXIDATION OF OILS

Проведено исследование процесса термического окисления подсолнечного и кокосового масел при 175°С в условиях поточного обжаривания в них картофеля и куриных наггетсов с отбором проб растительного масла через каждый час работы. Для определения количества продуктов окисления был использован метод спектрофотометрии. Установлено, что после 10 ч проведения обжарки исследованные фритюрные масла были пригодны для дальнейшего использования (Е < 15). Показатель оптической плотности кокосового масла независимо от вида обжариваемого в нем продукта в течение всего эксперимента был ниже аналогичного показателя подсолнечного масла. Предложена оптимальная температура нагрева кокосового масла для обжаривания во фритюре – не более 0,9 от температуры точки дымления. Показано более активное накопление вторичных продуктов окисления во фритюрном масле при обжаривании продукта животного происхождения по сравнению с обжариванием продукта растительного происхождения, что можно объяснить наличием в составе картофеля ингибиторов окисления (пероксидаза, каталаза, витамин С). The study of the process of thermal oxidation of sunflower and coconut oils at 175°C under conditions of in-line frying of potatoes and chicken nuggets in them with the sampling of vegetable oil every hour of operation was carried out. To determine the amount of oxidation products the method of spectrophotometry was used. It was found that after 10 hours of roasting, the studied fryer oils were suitable for further use (E < 15). The optical density index of coconut oil, regardless of the type of product fried in it, was lower than that of sunflower oil throughout the experiment. The optimal heating temperature of coconut oil for deep frying is proposed-no more than 0,9 of the temperature of the smoking point. A more active accumulation of secondary oxidation products in deep-frying oil is shown when frying an animal product compared to frying a vegetable product, which can be explained by the presence of oxidation inhibitors (peroxidase, catalase, vitamin C) in the composition of potatoes.

Metabolic Fingerprinting for Identifying the Mode of Action of the Fungicide SYP-14288 on Rhizoctonia solani

The fungicide SYP-14288 has a high efficiency, low toxicity, and broad spectrum in inhibiting both fungi and oomycetes, but its mode of action (MoA) remains unclear on inhibiting fungi. In this study, the MoA was determined by analyzing the metabolism and respiratory activities of Rhizoctonia solani treated by SYP-14288. Wild-type strains and SYP-14288-resistant mutants of R. solani were incubated on potato dextrose agar amended with either SYP-14288 or one of select fungicides acting on fungal respiration, including complex I, II, and III inhibitors; uncouplers; and ATP synthase inhibitors. Mycelial growth was measured under fungicides treatments. ATP content was determined using an ATP assay kit, membrane potential of mitochondria was detected with the JC-1 kit, and respiratory rate was calculated based on the measurement of oxygen consumption of R. solani. A model of metabolic fingerprinting cluster was established to separate oxidation inhibitors and phosphorylation inhibitors. All the results together displayed a clear discrimination between oxidation inhibitors and phosphorylation inhibitors, and the latter inhibited ATP synthase production having or uncoupling activities. Based on the model, SYP-14288 was placed in phosphorylation inhibitor group, because it significantly reduced ATP content and membrane potential of mitochondria while increasing respiratory rate in R. solani. Therefore, the MoA of SYP-14288 on R. solani was confirmed to involve phosphorylation inhibition and possibly uncoupling activity.

Author Correction: Artocarpus altilis extracts as a food-borne pathogen and oxidation inhibitors: RSM, COSMO RS, and molecular docking approaches

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Metabolic Remodeling Induced by Adipocytes: A New Achilles' Heel in Invasive Breast Cancer?

Metabolic reprogramming represents an important hallmark of cancer cells. Besides de novo fatty acid synthesis, it is now clear that cancer cells can acquire Fatty Acids (FA) from tumor-surrounding adipocytes to increase their invasive capacities. Indeed, adipocytes release FA in response to tumor secreted factors that are transferred to tumor cells to be either stored as triglycerides and other complex lipids or oxidized in mitochondria. Like all cells, FA can be released over time from triglyceride stores through lipolysis and then oxidized in mitochondria in cancer cells. This metabolic interaction results in specific metabolic remodeling in cancer cells, and underpins adipocyte stimulated tumor progression. Lipolysis and fatty acid oxidation therefore represent novel targets of interest in the treatment of cancer. In this review, we summarize the recent advances in our understanding of the metabolic reprogramming induced by adipocytes, with a focus on breast cancer. Then, we recapitulate recent reports studying the effect of lipolysis and fatty acid oxidation inhibitors on tumor cells and discuss the interest to target these metabolic pathways as new therapeutic approaches for cancer.

Artocarpus altilis extracts as a food-borne pathogen and oxidation inhibitors: RSM, COSMO RS, and molecular docking approaches

Lipid oxidation and microbial contamination are the major factors contributing to food deterioration. Food additives like antioxidants and antibacterials can prevent food spoilage by delaying oxidation and preventing the growth of bacteria. Artocarpus altilis leaves exhibited biological properties that suggested its use as a new source of natural antioxidant and antimicrobial. Supercritical fluid extraction (SFE) was used to optimize the extraction of bioactive compounds from the leaves using response surface methodology (yield and antioxidant activity). The optimum SFE conditions were 50.5 °C temperature, 3784 psi pressure and 52 min extraction time. Verification test results (Tukey’s test) showed that no significant difference between the expected and experimental DPPH activity and yield value (99%) were found. Gas-chromatography –mass spectrometry (GC-MS) analysis revealed three major bioactive compounds existed in A. altilis extract. The extract demonstrated antioxidant and antibacterial properties with 2,3-diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, ferric reducing ability of plasma (FRAP), hydroxyl radical scavenging activity, tyrosinase mushrrom inhibition of 41.5%, 8.15 ± 1.31 (µg of ascorbic acid equivalents), 32%, 37% and inhibition zone diameter of 0.766 ± 0.06 cm (B. cereus) and 1.27 ± 0.12 cm (E. coli). Conductor like screening model for real solvents (COSMO RS) was performed to explain the extraction mechanism of the major bioactive compounds during SFE. Molecular electrostatic potential (MEP) shows the probability site of nucleophilic and electrophilic attack during bacterial inhibition. Based on molecular docking study, non-covalent interactions are the main interaction occurring between the major bioactive compounds and bacteria (antibacterial inhibition).

ANTIOXIDANTS IN LIPIDS OF PEATS AND PEAT-FORMING PLANTS

The paper presents the results of a study of antioxidant activity of lipids isolated from bioproducer plants and peats sampled from a deposit on spurs of the Vasyugan Swamp. Analysis of antioxidants (AOs) is performed via the gasometric method using a model reaction initiated by cymene oxidation. It is found out that oxidation inhibitors of two types differing in reactivity and antioxidant content are present in peat lipids. In fuscum peats of the same type, the amount of AOs changes insignificantly with an increase in the depth of occurrence. A decrease in AOs of the second type is observed for peats with a high degree of decay. The experiments on plant humification in a peat deposit conducted during 2 years confirm the neoplasm of AOs of the second type, which is the result of microbiological activity. The content of lipids in plants after 2 years of humification is slightly increased, while the increase in AOs amount exceeding their content in peat lipids of the upper horizon is also observed. The depth of occurrence and the type of peat affect the content of AOs and the O/C ratio, as evidenced by the linear correlation dependence. The relationship between the antioxidant activity of lipids and the C/N ratio is not established.