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1.
HPP at 600 MPa alone, and in combination with US at 20 kHz (200 W), was applied to minimally processed potatoes of two commonly grown cultivars in Ireland. Changes in colour and microbial load (Enterobacteriaceae, total aerobic count, Salmonella, yeasts, and moulds) were monitored in vacuum-packaged potatoes during 14 days of storage at 4 °C. HPP and HPP/US significantly (p < 0.05) affected the colour parameters a*, b*, L*, and ΔE of minimally processed potatoes compared to the controls. Microbial growth was delayed in most of the treated samples with respect to those untreated (controls), while HPP completely inactivated Enterobacteriaceae in both cultivars. Total phenolic content and antioxidant activities were not altered in the treated samples of both varieties when compared to the controls. The levels of chlorogenic acid, ferulic acid, and caffeic acid were decreased after both treatments, with a significant (p < 0.05) increase in quinic acid in the treated samples as opposed to those untreated. A significant (p < 0.05) decrease in the levels of glycoalkaloids, namely α-chaconine and α-solanine, in HPP- and HPP/US-treated potatoes was also observed. These findings suggest that HPP and US can extend the shelf-life of minimally processed potatoes with a negligible impact on their antioxidant activity and phenolic content.  相似文献   

2.
The preservative properties of waste liquor obtained from octopus (Octopus vulgaris) cooking were investigated. Three different concentrations (high, medium, and low) of octopus cooking liquor (OCL) were included, respectively, in the aqueous packaging medium employed for mackerel (Scomber colias) canning. As a result, the canning process led to an increase (p < 0.05) of lipid content, lipid oxidation (development of fluorescent compounds and thiobarbituric acid reactive substances, TBARS), lipid hydrolysis (formation of free fatty acids, FFA) and ω3/ω6 ratio in fish muscle. In all canned samples, primary (peroxides) and secondary (TBARS) levels of lipid oxidation were low. Remarkably, the presence in the packaging medium of the high and medium OCL concentrations led to lower (p < 0.05) lipid oxidation development (fluorescent compound and TBARS detection, respectively). Furthermore, an increasing OCL presence led to an average decrease of peroxide and FFA content and to an average increase of the polyene index (PI). All OCL-packaged muscle showed lower average values of saturated fatty acids and ω3/ω6 ratio and higher average values of PI and monounsaturated fatty acid presence. This study provides a first approach to novel and beneficial use of the present marine waste to inhibit lipid damage of commercial canned fish.  相似文献   

3.
Light quality has been reported to influence the phytochemical profile of broccoli sprouts/microgreens; however, few studies have researched the influence on mature broccoli. This is the first study to investigate how exposing a mature glasshouse grown vegetable brassica, Tenderstem® broccoli, to different light wavelengths before harvest influences the phytochemical content. Sixty broccoli plants were grown in a controlled environment glasshouse under ambient light until axial meristems reached >1 cm diameter, whereupon a third were placed under either green/red/far-red LED, blue LED, or remained in the original compartment. Primary and secondary spears were harvested after one and three weeks, respectively. Plant morphology, glucosinolate, carotenoid, tocopherol, and total polyphenol content were determined for each sample. Exposure to green/red/far-red light increased the total polyphenol content by up to 13% and maintained a comparable total glucosinolate content to the control. Blue light increased three of the four indole glucosinolates studied. The effect of light treatments on carotenoid and tocopherol content was inconclusive due to inconsistencies between trials, indicating that they are more sensitive to other environmental factors. These results have shown that by carefully selecting the wavelength, the nutritional content of mature broccoli prior to harvest could be manipulated according to demand.  相似文献   

4.
Giant dielectric (GD) oxides exhibiting extremely large dielectric permittivities (ε’ > 104) have been extensively studied because of their potential for use in passive electronic devices. However, the unacceptable loss tangents (tanδ) and temperature instability with respect to ε’ continue to be a significant hindrance to their development. In this study, a novel GD oxide, exhibiting an extremely large ε’ value of approximately 7.55 × 104 and an extremely low tanδ value of approximately 0.007 at 103 Hz, has been reported. These remarkable properties were attributed to the synthesis of a Lu3+/Nb5+ co-doped TiO2 (LuNTO) ceramic containing an appropriate co-dopant concentration. Furthermore, the variation in the ε’ values between the temperatures of −60 °C and 210 °C did not exceed ±15% of the reference value obtained at 25 °C. The effects of the grains, grain boundaries, and second phase particles on the dielectric properties were evaluated to determine the dielectric properties exhibited by LuNTO ceramics. A highly dense microstructure was obtained in the as-sintered ceramics. The existence of a LuNbTiO6 microwave-dielectric phase was confirmed when the co-dopant concentration was increased to 1%, thereby affecting the dielectric behavior of the LuNTO ceramics. The excellent dielectric properties exhibited by the LuNTO ceramics were attributed to their inhomogeneous microstructure. The microstructure was composed of semiconducting grains, consisting of Ti3+ ions formed by Nb5+ dopant ions, alongside ultra-high-resistance grain boundaries. The effects of the semiconducting grains, insulating grain boundaries (GBs), and secondary microwave phase particles on the dielectric relaxations are explained based on their interfacial polarizations. The results suggest that a significant enhancement of the GB properties is the key toward improvement of the GD properties, while the presence of second phase particles may not always be effective.  相似文献   

5.
Most of the health benefits derived from cereals are attributed to their bioactive compounds. This study evaluated the levels of the bioactive compounds, and the antioxidant and starch-hydrolyzing enzymes inhibitory properties of six pipeline Striga-resistant yellow-orange maize hybrids (coded AS1828-1, 4, 6, 8, 9, 11) in vitro. The maize hybrids were grown at the International Institute of Tropical Agriculture (IITA), Nigeria. The bioactive compounds (total phenolics, tannins, flavonoids, and phytate) levels, antioxidant (DPPH and ABTS•+ scavenging capacity and reducing power) and starch-hydrolyzing enzymes (α-amylase and α-glucosidase) inhibitory activities of the maize hybrids were determined by spectrophotometry. At the same time, carotenoids were quantified using a reverse-phase HPLC system. The ranges of the bioactive compounds were: 11.25–14.14 mg GAE/g (total phenolics), 3.62–4.67 mg QE/g (total flavonoids), 3.63–6.29 mg/g (tannins), 3.66–4.31% (phytate), 8.92–12.11 µg/g (total xanthophylls), 2.42–2.89 µg/g (total β-carotene), and 3.17–3.77 µg/g (total provitamin A carotenoids). Extracts of the maize hybrids scavenged DPPH (SC50: 9.07–26.35 mg/mL) and ABTS•+ (2.65–7.68 TEAC mmol/g), reduced Fe3+ to Fe2+ (0.25 ± 0.64–0.43 ± 0.01 mg GAE/g), and inhibited α-amylase and α-glucosidase, with IC50 ranges of 26.28–52.55 mg/mL and 47.72–63.98 mg/mL, respectively. Among the six clones of the maize hybrids, AS1828-9 had the highest (p < 0.05) levels of tannins and phytate and the strongest antioxidant and starch-hydrolyzing enzymes inhibitory activities. Significant correlations were observed between total phenolics and the following: ABTS•+ (p < 0.01, r = 0.757), DPPH SC50 (p < 0.01, r = −0.867), reducing power (p < 0.05, r = 0.633), α-amylase IC50 (p < 0.01, r = −0.836) and α-glucosidase IC50 (p < 0.05, r = −0.582). Hence, the Striga-resistant yellow-orange maize hybrids (especially AS1828-9) may be beneficial for alleviating oxidative stress and postprandial hyperglycemia.  相似文献   

6.
Norway spruce (Picea abies (L.) H. Karst.) is one of the most important commercial tree species distributed naturally in the Boreal and subalpine forest zone of Europe. All parts of spruce trees, including needles, accumulate essential oils with a variety of chemical properties and ecological functions, such as modulating plant–insect communication. Annual needle samples from 15 trees (five from each of three habitats) of 15–17 years old were assayed for essential oils and their major compounds, including α-pinene, β-pinene, (1S)-(−)-α-pinene, and (1R)-(+)-α-pinene across a growing season. Results showed strong positive correlation between percentages of α- and β-pinene isomers (r = 0.69, p < 0.05) and between pinene isomers and essential oils: α-pinene correlated with essential oil stronger (r = 0.62, p < 0.05) than β-pinene (r = 0.33, p < 0.05). Correlation analyses performed with some weather conditions, including average monthly temperature, growing sum of effective temperatures over 5 °C, duration of sunshine, accumulated precipitation, relative humidity, and pressure, showed that temperature is the most important weather condition related to pinene dynamics: negative correlations of moderate strength were established between percentages of α- and β- pinenes and average monthly temperatures (r = −0.36, p < 0.01, n = 75 and r = −0.33, p < 0.01, n = 75, respectively). Out of pinene enantiomers, only (1S)-(−)-α-pinene showed some negative correlation with monthly temperature (r = −0.26, p < 0.05, n = 75). Different patterns of essential oil and pinene dynamics during growing season within separate habitats suggested that some genetic variables of Picea abies might be involved.  相似文献   

7.
Lentil protein isolate (LPI)-κ-carrageenan (κ-C) and -ι-carrageenan (ι-C) based microcapsules were prepared through spray-drying and freeze-drying to encapsulate flaxseed oil in order to reach final oil levels of 20% and 30%. Characteristics of the corresponding emulsions and their dried microcapsules were determined. For emulsion properties, all LPI-κ-C and LPI-ι-C emulsions remained 100% stable after 48 h, while the LPI emulsions destabilized quickly (p < 0.05) after homogenization mainly due to low emulsion viscosity. For spray-dried microcapsules, the highest yield was attributed to LPI-ι-C with 20% oil, followed by LPI-κ-C 20% and LPI-ι-C 30% (p < 0.05). Flaxseed oil was oxidized more significantly among the spray-dried capsules compared to untreated oil (p < 0.05) due to the effect of heat. Flaxseed oil was more stable in all the freeze-dried capsules and showed significantly lower oil oxidation than the untreated oil after 8 weeks of storage (p < 0.05). As for in vitro oil release profile, a higher amount of oil was released for LPI-κ-C powders under simulated gastric fluid (SGF), while more oil was released for LPI-ι-C powders under simulated gastric fluid and simulated intestinal fluid (SGF + SIF) regardless of drying method and oil content. This study enhanced the emulsion stability by applying carrageenan to LPI and showed the potential to make plant-based microcapsules to deliver omega-3 oils.  相似文献   

8.
L. indica L. cv. Mengzao, a medicinal plant of the Ixeris genus, is rich in flavonoids. In order to thoroughly analyze the the distribution and dynamic change of major flavonoids in its various parts from different growth periods, the flavonoids extracted from L. indica L. cv. Mengzao were identified and quantitatively analyzed by ultra-high-performance liquid chromatography mass spectrometer (LC-MS/MS). Results indicated that 15 flavonoids were identified from L. indica L. cv. Mengzao, and rutin, luteolin, luteolin-7-O-glucoside, kaempferol, quercetin, and apigenin are the major flavonoids in L. indica L. cv. Mengzao. In general, the total flavonoids’ content in different parts of L. indica L. cv. Mengzao followed the order flowers > leaves > stems > roots. Flowers and leaves are the main harvesting parts of L. indica L. cv. Mengzao, and the flowering period is the most suitable harvesting period. This study provides valuable information for the development and utilization of L. indica L. cv. Mengzao and determined the best part to harvest and the optimal time for harvesting.  相似文献   

9.
Our research focused on the hypoglycemic capability and the possible mechanisms of extract and fractions from Polygoni Avicularis Herba (PAH) based on α-glucosidase, α-amylase inhibition assays, glucose uptake experiment, HPLC-MS analysis, and molecular docking experiment. In addition, DPPH, ABTS, and FRAP assays were used for determining the antioxidant capability. The results of total flavonoids and phenolics contents showed that ethyl acetate fraction (EAF) possessed the highest flavonoids and phenolics with values of 159.7 ± 2.5 mg rutin equivalents/g and 107.6 ± 2.0 mg galic acid equivalents/g, respectively. The results of in vitro hypoglycemic activity showed that all samples had effective α-glucosidase inhibition capacities, and EAF possessed the best inhibitory effect with IC50 value of 1.58 ± 0.24 μg/mL. In addition, n-butanol fraction (NBF) significantly promoted the glucose uptake rate of 3T3-L1 adipocytes. HPLC-MS analysis and molecular docking results proved the interactions between candidates and α-glucosidase. The results of antioxidation capacities showed that EAF possessed the best antioxidation abilities with DPPH, ABTS, and FRAP. In summary, the hypoglycemic activity of PAH might be related to the inhibition of α-glucosidase (EAF > PEF > NBF) and the promotion of glucose uptake in 3T3-L1 adipocytes (NBF). Simultaneously, the antioxidation capacity of PAH might be related to the abundant contents of flavonoids and other phenolics (EAF > PEF > NBF).  相似文献   

10.
Postovulatory aging of the mammalian oocytes causes deterioration of oocytes through several factors including oxidative stress. Keeping that in mind, we aimed to investigate the potential of a well-known antioxidant, resveratrol (RV), to evaluate the adverse effects of postovulatory aging in porcine oocytes. After in vitro maturation (IVM), a group of (25–30) oocytes (in three replicates) were exposed to 0, 1, 2, and 4 μmol/L of RV, respectively. The results revealed that the first polar body (PB1) extrusion rate of the oocytes significantly increased when the RV concentration reached up to 2 μmol/L (p < 0.05). Considering optimum RV concentration of 2 μmol/L, the potential of RV was evaluated in oocytes aged for 24 and 48 h. We used fluorescence microscopy to detect the relative level of reactive oxygen species (ROS), while GHS contents were measured through the enzymatic method. Our results revealed that aged groups (24 h and 48 h) treated with RV (2 μmol/L) showed higher (p < 0.05) ROS fluorescence intensity than the control group, but lower (p < 0.05) than untreated aged groups. The GSH content in untreated aged groups (24 h and 48 h) was lower (p < 0.05) than RV-treated groups, but both groups showed higher levels than the control. Similarly, the relative expression of the genes involved in antioxidant activity (CAT, GPXGSH-Px, and SOD1) in RV-treated groups was lower (p < 0.05) as compared to the control group but higher than that of untreated aged groups. Moreover, the relative mRNA expression of caspase-3 and Bax in RV-treated groups was higher (p < 0.05) than the control group but lower than untreated groups. Furthermore, the expression of Bcl-2 in the RV-treated group was significantly lower than control but higher than untreated aged groups. Taken together, our findings revealed that the RV can increase the expression of antioxidant genes by decreasing the level of ROS, and its potent antiapoptotic effects resisted against the decline in mitochondrial membrane potential in aged oocytes.  相似文献   

11.
Candida antarctica lipase B-catalyzed hydrolysis of carbocyclic 5–8-membered cis β-amino esters was carried out in green organic media, under solvent-free and ball-milling conditions. In accordance with the high enantioselectivity factor (E > 200) observed in organic media, the preparative-scale resolutions of β-amino esters were performed in tBuOMe at 65 °C. The unreacted β-amino ester enantiomers (1R,2S) and product β-amino acid enantiomers (1S,2R) were obtained with modest to excellent enantiomeric excess (ee) values (ees > 62% and eep > 96%) and in good chemical yields (>25%) in one or two steps. The enantiomers were easily separated by organic solvent/H2O extraction.  相似文献   

12.
An intermolecular radical based distal selectivity in appended alkyl chains has been developed. The selectivity is maximum when the distal carbon is γ to the appended group and decreases by moving from γδε positions. In –COO– linked alkyl chains, the same distal γ-selectivity is observed irrespective of its origin, either from the alkyl carboxy acid or alkyl alcohol. The appended groups include esters, N–H protected amines, phthaloyl, sulfone, sulfinimide, nitrile, phosphite, phosphate and borate esters. In borate esters, boron serves as a traceless directing group, which is hitherto unprecedented for any remote Csp3–H functionalization. The selectivity order follows the trend: 3° benzylic > 2° benzylic > 3° tertiary > α to keto > distal methylene (γ > δ > ε). Computations predicted the radical stability (thermodynamic factors) and the kinetic barriers as the factors responsible for such trends. Remarkably, this strategy eludes any designer catalysts, and the selectivity is due to the intrinsic substrate reactivity.

An intermolecular amination at the distal methylene carbon has been realized in an appended alkyl chain with electron withdrawing groups. Traceless remote Csp3–H functionalization has been accomplished using borate esters.  相似文献   

13.
The chemical profile of the female inflorescence extracts from seven Cannabis sativa L. dioecious cultivars (Carmagnola, Fibranova, Eletta Campana, Antal, Tiborszallasi, Kompolti, and Tisza) was monitored at three harvesting stages (4, 14, and 30 September), reaching from the beginning of flowering to end of flowering/beginning of seed formation, using untargeted nuclear magnetic resonance (NMR) and targeted (ultra-high-performance liquid chromatography (UHPLC) and spectrophotometry) analyses. The tetrahydrocannabinol content was always below the legal limits (<0.6%) in all the analyzed samples. The NMR metabolite profile (sugars, organic acids, amino acids, and minor compounds) subjected to principal components analysis (PCA) showed a strong variability according to the harvesting stages: samples harvested in stage I were characterized by a high content of sucrose and myo-inositol, whereas the ones harvested in stage II showed high levels of succinic acid, alanine, valine, isoleucine, phenylalanine, and threonine. Samples harvested in stage III were characterized by high levels of glucose, fructose, choline, trigonelline, malic acid, formic acid, and some amino acids. The ratio between chlorophylls and carotenoids content indicated that all plants grew up exposed to the sun, the Eletta Campana cultivar having the highest pigment amount. Tiborszallasi cultivar showed the highest polyphenol content. The highest antioxidant activity was generally observed in stage II. All these results suggested that the Cannabis sativa L. inflorescences of each analyzed dioecious hemp cultivar presented a peculiar chemical profile affected by the harvesting stage. This information could be useful for producers and industries to harvest inflorescences in the appropriate stage to obtain samples with a peculiar chemical profile suitable for proper applications.  相似文献   

14.
Interleukin-1β (IL-1β), a product of the NLRP3 inflammasome, modulates cardiac contractility and diastolic function. We proposed that OLT1177® (dapansutrile), a novel NLRP3 inhibitor, could preserve contractile reserve and diastolic function after myocardial infarction (MI). We used an experimental murine model of severe ischemic cardiomyopathy through the ligation of the left coronary artery without reperfusion, and after 7 days randomly assigned mice showing large anterior MI (>4 akinetic segments), increased left ventricular (LV) dimensions ([LVEDD] > 4.4 mm), and reduced function (LV ejection fraction < 40%) to a diet that was enriched with OLT1177® admixed with the chow in the diet at 3.75 g/kg (Group 1 [n = 10]) or 7.5 g/kg (Group 2 [n = 9]), or a standard diet as the no-treatment control group (Group 3 [n = 10]) for 9 weeks. We measured the cardiac function and contractile reserve with an isoproterenol challenge, and the diastolic function with cardiac catheterization at 10 weeks following the MI surgery. When compared with the control (Group 3), the mice treated with OLT1177 (Group 1 and 2) showed significantly greater preservation of their contractile reserve (the percent increase in the left ventricular ejection fraction [LVEF] after the isoproterenol challenge was +33 ± 11% and +40 ± 6% vs. +9 ± 7% in the standard diet; p < 0.05 and p < 0.005 for Group 1 and 2, respectively) and of diastolic function measured as the lower left ventricular end-diastolic pressure (3.2 ± 0.5 mmHg or 4.5 ± 0.5 mmHg vs. 10.0 ± 1.6 mmHg; p < 0.005 and p < 0.009 respectively). No differences were noted between the resting LVEF of the MI groups. These effects were independent of the effects on the ventricular remodeling after MI. NLRP3 inflammasome inhibition with OLT1177® can preserve β-adrenergic responsiveness and prevent left ventricular diastolic dysfunction in a large non-reperfused anterior MI mouse model. OLT1177® could therefore be used to prevent the development of heart failure in patients with ischemic cardiomyopathy.  相似文献   

15.
The current study was intended to explore the phytochemical profiling and therapeutic activities of Putranjiva roxburghii Wall. Crude extracts of different plant parts were subjected to the determination of antioxidant, antimicrobial, antidiabetic, cytotoxic, and protein kinase inhibitory potential by using solvents of varying polarity ranges. Maximum phenolic content was notified in distilled water extracts of the stem (DW-S) and leaf (DW-L) while the highest flavonoid content was obtained in ethyl acetate leaf (EA-L) extract. HPLC-DAD analysis confirmed the presence of various polyphenols, quantified in the range of 0.02 ± 0.36 to 2.05 ± 0.18 μg/mg extract. Maximum DPPH scavenging activity was expressed by methanolic extract of the stem (MeOH-S). The highest antioxidant capacity and reducing power was shown by MeOH-S and leaf methanolic extract (MeOH-L), respectively. Proficient antibacterial activity was shown by EA-L extract against Bacillus subtilis and Escherichia coli. Remarkable α-amylase and α-glucosidase inhibition potential was expressed by ethyl acetate fruit (EA-F) and n-Hexane leaf (nH-L) extracts, respectively. In case of brine shrimp lethality assay, 41.67% of the extracts (LC50 < 50 µg/mL) were considered as extremely cytotoxic. The test extracts also showed mild antifungal and protein kinase inhibition activities. The present study explores the therapeutic potential of P. roxburghii and calls for subsequent studies to isolate new bioactive leads through bioactivity-guided isolation.  相似文献   

16.
The main objective of the current study was the extraction, purification, and enzymatic characterization of a potent proteinaceous amylase inhibitor from Moringa oleifera. The antimicrobial potential and insecticide effects against C. maculates insect larvae were also studied. The α-amylase inhibitor was extracted in methanol (with an inhibitory activity of 65.6% ± 4.93). Afterwards, the inhibitor αAI.Mol was purified after a heat treatment at 70 °C for 15 min followed by one chromatographic step of Sephadex G-50. An apparent molecular weight of 25 kDa was analyzed, and the N-terminal sequence showed the highest identity level (89%) with the monomeric α-amylase inhibitor from Triticum dicoccoides. αAI.Mol was found to tolerate pH values ranging from 5.0 to 11.0 and showed maximal activity at pH 9.0. Thermal stability was remarkably important, since the inhibitory activity was maintained at 55% after 1 h of incubation at 70 °C and at 53% after an incubation of 45 min at 80 °C. The potency of the current purified inhibitor against amylases from different origins indicates that αAI.Mol seems to possess the highest affinity toward human salivary α-amylase (90% inhibitory activity), followed by the α-amylase of insects Callosobruchus maculatus and Tribolium confusum (71% and 61%, respectively). The kinetic parameters were also calculated, and the Kmax and Vmax of the digestive amylase were estimated at 185 (mmol/min/mg) and 0.13 mM, respectively. The inhibitor possesses a strong bactericidal effect against Gram+ and Gram- strains, and the MIC values were >1 against B. cereus but >6 against E. coli. Interestingly, the rates of survival and pupation of C. maculates insect larvae were remarkably affected by the purified αAI.Mol from Moringa oleifera.  相似文献   

17.
Cistus ladanifer is a Mediterranean native plant from which valuable products, such as essential oil, are obtained. Manual harvesting of the plants in wild shrublands is usual during short periods of time. Their mechanised harvesting could increase the volume of harvested plants and prevent fires, further storage of the plants collected being necessary. The objective of this work is to study the influence of the storage period of mechanically harvested bales on the essential oil yield and qualitative composition. The harvesting trials were carried out with an adapted commercial harvester baler and the storage of the bales was performed indoors during 1–7 days, 15–30 days and 100–120 days. Afterwards, the bales were crushed (30 mm) and distilled in a 30 litre stainless steel still with saturated steam (0.5 bar). The essential oil components were identified by GC-MS and quantified by GC-FID. The storage of mechanically harvested Cistus ladanifer does not decrease the oil yield of steam distillation on a pilot scale. However, it leads to differences in the quantitative composition of the essential oils, decreasing the total monoterpene compounds content and increasing that of oxygenated sesquiterpenes, especially when the biomass is stored for 100–120 days, without affecting its qualitative composition.  相似文献   

18.
Bioinsecticides are regarded as important alternatives for controlling agricultural pests. However, few studies have determined the persistence of these compounds in stored grains. This study aimed at optimizing and validating a fast and effective method for extraction and quantification of residues of safrole (the main component of Piper hispidinervum essential oil) in cowpea beans. It also sought to assess the persistence of this substance in the grains treated by contact and fumigation. The proposed method used headspace solid-phase microextraction (HS-SPME) and gas chromatography with a flame ionization detector (GC/FID). Factors such as temperature, extraction time and type of fiber were assessed to maximize the performance of the extraction technique. The performance of the method was appraised via the parameters selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), precision, and accuracy. The LOD and LOQ of safrole were 0.0057 and 0.019 μg kg−1, respectively and the determination coefficient (R2) was >0.99. The relative recovery ranged from 99.26 to 104.85, with a coefficient of variation <15%. The validated method was applied to assess the persistence of safrole residue in grains, where concentrations ranged from 1.095 to 0.052 µg kg−1 (contact) and from 2.16 to 0.12 µg kg −1 (fumigation). The levels measured up from the fifth day represented less than 1% of the initial concentration, proving that safrole have low persistence in cowpea beans, thus being safe for bioinsecticide use. Thus, this work is relevant not only for the extraction method developed, but also for the possible use of a natural insecticide in pest management in stored grains.  相似文献   

19.
Exposure to particulate matter (PM) is related to various respiratory diseases, and this affects the respiratory immune system. Alveolar macrophages (AMs), which are defenders against pathogens, play a key role in respiratory inflammation through cytokine production and cellular interactions. Coconut oil demonstrates antioxidant and anti-inflammatory properties, and it is consumed worldwide for improved health. However, reports on the protective effects of coconut oil on the PM-induced respiratory immune system, especially in AMs, are limited. In this study, we generated artificial PM (APM) with a diameter approximately of 30 nm by controlling the temperature, and compared its cytotoxicity with diesel exhaust particles (DEP). We also investigated the antioxidant and anti-inflammatory effects of coconut oil in APM– and DEP–stimulated AMs, and the underlying molecular mechanisms. Our results showed that APM and DEP had high cytotoxicity in a dose-dependent manner in AMs. In particular, APM or DEP at 100 μg/mL significantly decreased cell viability (p < 0.05) and significantly increased oxidative stress markers such as reactive oxygen species (p < 0.01); the GSSH/GSH ratio (p < 0.01); and cytokine production, such as tumor necrosis factor-α (p < 0.001), interleukin (IL)-1β (p < 0.001), and IL-6 (p < 0.001). The expression of the genes for chemokine (C-X-C motif) ligand-1 (p < 0.05) and monocyte chemoattractant protein-1 (p < 0.001); and the proteins toll-like receptor (TLR) 4 (p < 0.01), mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (p < 0.001), p38 (p < 0.001); and extracellular receptor-activated kinase (p < 0.001), were also upregulated by PM. These parameters were reversed upon treatment with coconut oil in APM– or DEP–stimulated AMs. In conclusion, coconut oil can reduce APM– or DEP–induced inflammation by regulating the TLR4/MAPK pathway in AMs, and it may protect against adverse respiratory effects caused by PM exposure.Exposure to particulate matter (PM) is related to various respiratory diseases, and this affects the respiratory immune system. Alveolar macrophages (AMs), which are defenders against pathogens, play a key role in respiratory inflammation through cytokine production and cellular interactions. Coconut oil demonstrates antioxidant and anti-inflammatory properties, and it is consumed worldwide for improved health. However, reports on the protective effects of coconut oil on the PM-induced respiratory immune system, especially in AMs, are limited. In this study, we generated artificial PM (APM) with a diameter approximately of 30 nm by controlling the temperature, and compared its cytotoxicity with diesel exhaust particles (DEP). We also investigated the antioxidant and anti-inflammatory effects of coconut oil in APM– and DEP–stimulated AMs, and the underlying molecular mechanisms. Our results showed that APM and DEP had high cytotoxicity in a dose-dependent manner in AMs. In particular, APM or DEP at 100 μg/mL significantly decreased cell viability (p < 0.05) and significantly increased oxidative stress markers such as reactive oxygen species (p < 0.01); the GSSH/GSH ratio (p < 0.01); and cytokine production, such as tumor necrosis factor-α (p < 0.001), interleukin (IL)-1β (p < 0.001), and IL-6 (p < 0.001). The expression of the genes for chemokine (C-X-C motif) ligand-1 (p < 0.05) and monocyte chemoattractant protein-1 (p < 0.001); and the proteins toll-like receptor (TLR) 4 (p < 0.01), mitogen-activated protein kinase (MAPK), and c-Jun N-terminal kinase (p < 0.001), p38 (p < 0.001); and extracellular receptor-activated kinase (p < 0.001), were also upregulated by PM. These parameters were reversed upon treatment with coconut oil in APM– or DEP–stimulated AMs. In conclusion, coconut oil can reduce APM– or DEP–induced inflammation by regulating the TLR4/MAPK pathway in AMs, and it may protect against adverse respiratory effects caused by PM exposure.  相似文献   

20.
In women with preeclampsia (PE), endothelial cell (EC) dysfunction can lead to altered secretion of paracrine factors that induce peripheral vasoconstriction and proteinuria. This study examined the hypothesis that PE sera may directly or indirectly, through human umbilical vein ECs (HUVECs), stimulate phospholipase C-γ1-1,4,5-trisphosphate (PLC-γ1-IP3) signaling, thereby increasing protein kinase C-α (PKC-α) activity, collagen I expression and intracellular Ca2+ concentrations ([Ca2+]i) in human umbilical artery smooth muscle cells (HUASMCs). HUASMCs and HUVECs were cocultured with normal or PE sera before PLC-γ1 silencing. Increased PLC-γ1 and IP3 receptor (IP3R) phosphorylation was observed in cocultured HUASMCs stimulated with PE sera (P<0.05). In addition, PE serum significantly increased HUASMC viability and reduced their apoptosis (P<0.05); these effects were abrogated with PLC-γ1 silencing. Compared with normal sera, PE sera increased [Ca2+]i in cocultured HUASMCs (P<0.05), which was inhibited by PLC-γ1 and IP3R silencing. Finally, PE sera-induced PKC-α activity and collagen I expression was inhibited by PLC-γ1 small interfering RNA (siRNA) (P<0.05). These results suggest that vasoactive substances in the PE serum may induce deposition in the extracellular matrix through the activation of PLC-γ1, which may in turn result in thickening and hardening of the placental vascular wall, placental blood supply shortage, fetal hypoxia–ischemia and intrauterine growth retardation or intrauterine fetal death. PE sera increased [Ca2+]i and induced PKC-α activation and collagen I expression in cocultured HUASMCs via the PLC-γ1 pathway.  相似文献   

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