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Objective: Compare in cucumber cultivation a commercial pest control program vs a biological pest control program evaluating quality and production parameters. Design/methodology/approach: The study was carried out in glass greenhouses classified as high technology, under a cooling system consisting of wet walls and extractors, heating that works by irradiation, automated irrigation. Two treatments were evaluated: biological control of pests in area A and the second, a commercial control program in area B, both in Persian cucumber (Cucumis sativus) of the Jawell variety. Each area of 160 m², in separate areas. One plant was considered as an experimental unit, the total of experimental units were 41, 600 plants for each area, 80 grooves were considered within each area with a length of 100 meters with 52 pillows of coconut fiber, whose pillows contain five cubes of rockwool with a plant two heads each cube, giving a total of 10 plants per pillow and 520 plants per groove. The average planting density was 3.42 plants / m². The biological control program consisted of releasing the mite (Amblyseius swirskii) for the control of thrips; the release of the wasp (Aphidius colemani) for aphid control; mites (Phytoseiulus persimilis) and (Amblyseius californicus) for the control of red spider mites and the application of the entomopathogenic nematode (Steinernema fetiae). The commercial-chemical control was in accordance with COFEPRIS (2019). The chemical products Actara (Thiametoxam), Beleaf (Flonicamid), Confidor 350 sc (Imidacloprid), Plenum 50 gs (Pymetrozine) and Talstar 100 CE (Biphentrine) were applied to control aphids. Tracer (Spinosad), Exalt (Spinetoram) and Beleaf (Flonicamid) for thrips control. Agirmec (Abamectina) and Talstar (Bifentrina) for the control of red spider, and finally Trigard (Cyromazina) for the control of fungus gnat larvae. The evaluated variables were fruit quality, total production and incidence of pests. A completely randomized experimental design was applied. To analyze the total number of boxes produced, the statistical T-Student test was used for normal data between two independent samples and the Mann-Whitney test was used to compare the variables weight quality and weight loss with the data obtained, with a level of significance of P³0.05 to determine differences. A correlation (r) was made between the incidence of thrips (Thrips tabaci) and the incidence of the biological control Amblyseius swirskii, to compare the biological control (A) and the commercial control (B). Results: The results show that the production method using a biological pest control system was just as efficient as the chemical control program, in variables such as fruit weight, number of quality cucumber boxes obtained and incidence of pests. and its biological control. Limitations on study/implications: It is important to carry out further studies under open-air conditions where biotic and abiotic factors are different and in other regions, in addition to testing other registered biological products. Findings/conclusions: Biological and chemical control are complementary, an integrated control would help to slowly adapt a company for a subsequent application of only biological pest control, facilitating regularization and certification procedures involving the use of chemicals. In this biological control program, a more continuous and distributed release of A. swirskii is proposed during the weeks of cultivation, which will maintain more uniform and constant populations, this to avoid development of high populations of thrips and allow better control of this plague. It is necessary to evaluate both control programs during the spring-summer season to be able to compare the efficiency of these for each season and annually.

Arabinoxylans (AX) are polysaccharides with antioxidant activity and emulsifying properties, which make them an attractive alternative for its potential application as a natural antioxidant in oils. Therefore, this work aimed to investigate the effect of ultrasonic treatment of AX on their antioxidant capacity and its ability to improve the oxidative stability of soybean oil. For this purpose, AX were exposed to ultrasonic treatment at 25% (100 W, AX-1) and 50% (200 W, AX-2) power and an operating frequency of 20 KHz during 15 min, and their macromolecular properties (weight average molecular weight (Mw), polydispersity index and intrinsic viscosity) were evaluated. The antioxidant capacity of AX was determined by the DPPH assay and Rancimat test. Results showed that ultrasonic treatment did not affect the molecular identity of the polysaccharide but modified its Mw distribution. AX-1 showed the highest antioxidant activity (75% inhibition) at 533 &micro, g/mL by the DPPH method compared to AX and AX-2. AX at 0.25% (w/v) and AX-1 at 0.01% (w/v) exerted the highest protective effects on oxidative stability of soybean oil with induction periods of 7.69 and 5.54 h, respectively. The results indicate that AX could be a good alternative for the potential application as a natural antioxidant in oils.

The main chemical composition and pharmacological potential of propolis from arid and semi-arid regions of the Sonoran Desert have been previously reported. Caborca propolis (CP), from an arid zone of the Sonoran Desert, has shown a polyphenolic profile that suggests a mixed plant origin, presenting poplar-type markers, as well as a 6-methoxylated flavonoid, xanthomicrol, characteristic of Asteraceae plants. In addition, CP has shown significant antioxidant properties and antiproliferative activity on cancer cells. In this study, we analyzed the influence of collection time on the chemical constitution, antiproliferative activity and protective capacity of CP against reactive oxygen species (ROS), by using HPLC&ndash, UV&ndash, diode array detection (DAD) analysis, 3-(4,5-dimethylthiazol-2-yl)-2,5-Dimethyltetrazoliumbromide (MTT) and 2,2-diphenyl-1-picryl-hydrazyl (DPPH) assays, as well as cellular antioxidant activity (CAA) assay on murine B-cell lymphoma M12.C3.F6 cells. HPLC&ndash, DAD analyses of seasonally collected CP (one-year period) revealed quantitative differences among the most abundant CP constituents: pinocembrin, galangin, chrysin and pinobanksin-3-O-acetate. Though all seasonal samples of CP induced an antiproliferative effect in M12.C3.F6 cells, CP from autumn showed the highest inhibitory activity (IC50: 5.9 &plusmn, 0.6 &micro, g/mL). The DPPH assay pointed out that CP collected in autumn presented the highest antioxidant potential (IC50: 58.8 &plusmn, 6.7 &micro, g/mL), followed by winter (65.7 &plusmn, 12.2 &micro, g/mL) and spring (67.0 &plusmn, 7.5 &micro, g/mL), meanwhile, the summer sample showed a lesser antioxidant capacity (IC50: 98.7 &plusmn, 2.5 &micro, g/mL). The CAA assay demonstrated that CP induced a significant protective effect against ROS production elicited by H2O2 in M12.C3.F6 cells. Pretreatment of M12.C3.F6 cells with CP from spring and autumn (25 and 50 &micro, g/mL for 1 h) showed the highest reduction in intracellular ROS induced by H2O2 (1 and 5 mM). These results indicate that the antiproliferative effect and cellular antioxidant activity of CP are modulated by quantitative fluctuations in its polyphenolic profile due to its collection time.

The effect of the addition of natural antioxidants on oxidative stability of ray ( Rhinoptera bonasus) liver oil was evaluated. Different concentrations of rosemary extract, α-tocopherol, and caffeic acid (w/w) were added to the oil. Afterwards, concentration of each antioxidant that gave the highest stability was used in an accelerated stability test (Schaal method). The protective effect was established by the retention in the oil of fatty acids eicosapentaenoic (EPA) and docosahexaenoic (DHA), and concentration of volatile compounds. The best concentrations were: 2.5% of rosemary extract, 0.5% of α-tocopherol, and 0.06% of caffeic acid. Rosemary extract showed to be the product with the greatest ability to retard oxidation, followed by α-tocopherol, and caffeic acid. A high correlation between the peroxide value and the concentration of the 2-decenal, 1-penten-3-ol, and 2-octenal, was reported, suggesting that this can be used to assess the development of oxidative rancidity in the ray liver oil.

The effect of natural antioxidants was tested by oxidative stability index (OSI) in refined soybean oil (RSO) using Rancimat method. Phenolic compounds of Thompson grape pomace were extracted with 95:5 (v : v) ethanol : water. The antioxidant activity of grape pomace extract (GPE) obtained was compared with those of rosemary extract (RE), and tocopherols mix (TM) known as covi-ox T-70. The synergistic effect of citric acid was also evaluated. Results showed a total phenols content of 17.39 mg (+)-catechin equivalents per g of GPE. Thompson GPE at 0.3 and 0.5% (w/w) exhibited greater antioxidant activity than TM. RSO containing GPE or RE at 0.5% (w/w) showed an OSI higher than 48 h at 110C. Citric acid did not show synergistic effect with GPE. However, a synergistic effect for TM at 0.02% (w/w) with citric acid at 1.0% (w/w) was observed. Citric acid at 2.0% (w/w) with RE at all concentrations tested also displayed synergism. PRACTICAL APPLICATIONS Synthetic antioxidants are widely used in the food industry to delay fat oxidation; however, their utilization has been questioned due to toxicology concerns. Researchers have recognized the need to identify new natural antioxidants to use as additives. In this study, we measured total phenolics content of Thompson grape pomace extract (GPE) and found that the antioxidant activity of this extract was stronger than tocopherols from soybean oil. We propose that GPE can have applications as a food antioxidant.

Lipid composition by class, fatty acids, natural antioxidants (carotenes, tocopherols) and physicochemical characteristics of liver oil from three commercial rays, Rhinoptera bonasus (Chucha), Aetobatus narinari (Pinta) and Dasyatis americana (Bala) from the Gulf of Mexico were analyzed. Liver oil yield for R. bonasus, A. narinari and D. americana were of 43.04, 41.2 and 38.2% (wet weight), respectively. Triacylglycerols were the most abundant lipid by class in R. bonasus (68.9%), A. narinari (85.9%) and D. americana (81.6%), while sterols esters, sterols, di- and monoacylglycerides, polar lipids and wax esters were found in minor proportions. Species showed similar carotenes concentration, 8.7, 12.8 and 8.0 μg/g for R. bonasus, A. narinari and D. americana, respectively. α-tocopherol concentration was higher (p < 0.05) for A. narinari (46.7 mg/100 g) than for R. bonasus (21.0 mg/100 g) and D. americana (13.7 mg/100 g). Omega-3 polyunsaturated fatty acids in R. bonasus were high with docosahexaenoic acid (12.1%) in a higher proportion than eicosapentaenoic acid (7%).

The liver oil of the tecolote ray ( Rhinoptera steindechneri ) was characterized in terms of its lipid by-class composition and fatty acid profile, natural antioxidants content, oxidative resistance and physicochemical properties. The liver oil content was considered high and fluctuated between 57% and 67% of the liver weight (w/w). The carotenes and α -tocopherols levels varied from 2.9 to 17.4 mg/100 g of oil and 3.0 to 15.2 mg/100 g of oil, respectively. The oxidative resistance reported as the induction period varied between 2.1 and 4.7 h, showing a very stable oil due to its level of natural antioxidants. The triglycerides were the major lipid by-class in the oil (703–790 mg/oil g), followed in a smaller proportion by sterol esters, polar lipids and free sterols. The liver oil of tecolote ray proved to be an adequate source of the n-3 polyunsaturated fatty acids EPA and DHA, similar to the traditional codfish liver oil.

The omega-3 polyunsaturated fatty acids (PUFA) such as eicosapentaenoic (EPA) and docosahexaenoic (DHA), have been recognized for their important role in health. EPA has several beneficial effects regarding coronary heart disease, while DHA has been found to be important for the development of the brain and retina. The increase in the consumption of fish oil, a commercial source of PUFA, has made necessary the search for new fish species rich in PUFA that could be used as raw material for the fish oil production. The lipid, fatty acid composition and natural antioxidant contents (carotene, tocopherol) were analyzed for the liver oil of Dasyatis brevis (arenera) and Gymnura marmorata (mariposa), two ray species commercially captured in the Gulf of California. The liver oil yield 25–50% (w/w) for D. brevis and 38–56% for G. marmorata. The triglyceride fraction was the major lipid class (577–758 mg/g) for both species, with smaller proportions of sterol esters, free sterols, polar lipids and diacyl glyceryl ethers. D. brevis showed a greater carotene and tocopherols concentration (6.9 mg/100 g, 25.3 mg/100 g, respectively) than G. marmorata (1.8 mg/100 g, 2.8 mg/100 g, respectively). The content of saturated and monoenoic fatty acid was similar for both species, however, the liver oil of G. marmorata had twice as much DHA than D. brevis. The composite percentage composition of DHA plus EPA with respect to the total of fatty acids in liver oil was 18% for G. marmorata and 16% for D. brevis. The liver oil of G. marmorata and D. brevis represent a new source of omega-3 PUFA that can be used for human and animal nutrition.

The purpose of this study was to evaluate the trans fatty acid (TFA) composition and the tocopherol content in vegetable oils produced in Mexico. Sample oils were obtained from 18 different oil refining factories, which represent 72% of the total refineries in Mexico. Fatty acids and TFA isomers were determined by gas chromatography using a 100-m fused-silica capillary column (SP-2560). Tocopherol content was quantified by normal-phase high-performance liquid chromatography using an ultraviolet detector and a LiChrosorb Si60 column (25 cm). Results showed that 83% of the samples corresponded to soybean oil. Seventy-two percent of the oils analyzed showed TFA content higher than 1%. Upon comparing the tocopherol contents in some crude oils to their corresponding deodorized samples, a loss of 40–56% was found. The processing conditions should be carefully evaluated in order to reduce the loss of tocopherols and the formation of TFA during refining.

The phenolic compounds of Thompson grape bagasse were extracted using a 95:5 (vol/vol) ethanol/water mixture. Measurement of the antioxidant activity in refined soybean oil of bagasse grape extract was performed by using two different methods, the Rancimat method and the Schaal oven method in conjunction with peroxide value determination. The antioxidant activity of the extract was compared to the tertiary butyl hydroquinone (TBHQ) and butylated hydroxyanisole (BHA) activity. The bagasse grape extract showed similar antioxidant activities in both methods employed. At all concentrations tested [0.1, 0.3 and 0.5% of total phenols (TP)] the extract exhibited appreciable activity, which exceeded the activity of BHA. At some concentrations (0.3 and 0.5% TP) the extract exhibited activity comparable to that of TBHQ. Bagasse is a byproduct with a high content of phenolic compounds and is a good source of natural antioxidants.