In vitro antibacterial activity of thymol and carvacrol and their effects on broiler chickens challenged with Clostridium perfringens

Background： In the post-antibiotic era, essential oils （EO） are promising alternatives to growth-promoting antibiotics. The aim of the present study was to investigate the antibacterial activities of an EO product and its components thymol and carvacrol in vitro, and the efficacy of EO to control Clostridium perffingens challenge in broiler chickens. Results： The in vitro minimum inhibitory concentration assay showed strong antibacterial activity of the EO product, thymol, and carvacrol against pathogenic Escherichia col~, C. perffingens, and Salmonella strains, and weak activity towards beneficial Lactobacillus strains. Besides, an additive effect was observed between thymol and carvacrol. The in vivo study was carried out with 448 male broiler chicks following a 4 x 2 factorial arrangement to test the effects of EO supplementation （0, 60, 120, or 240 mg/kg EO in wheat-based diet）, pathogen challenge （with or without oral gavage of C. perfr/ngens from day 14 to day 20） and their interactions. Each treatment consisted of eight replicate pens （seven birds/pen）. The challenge led to macroscopic gut lesions, and resulted in a significant increase in ileal populations of C. perffingens and Eschefichia subgroup （P ≤ 0.05） on day 21. Dietary EO supplementation did not influence C. perfringens numbers, but linearly alleviated intestinal lesions on day 21 and 28 （P= 0.010 and 0.036, respectively）, and decreased Eschefichia populations in ileum with increased EO dosages （P = 0.027 and 0.071 for day 21 and 28, respectively）. For caecum, EO quadratically influenced Lactobacillus populations on day 21 （P = 0.002）, and linearly decreased the numbers of total bacteria and Eschefichio on day 28 （P = 0.026 and 0.060, respectively）. Mean thymol and carvacrol concentrations in the small intestine were 0.21 and 0.20 μg/g in intestinal digesta （wet weight）, respectively, for birds fed 60 mg/kg EO, and 0.80 and 0.71 μg/g, respectively, for birds fed 240 mg/kg EO. Conclusions： These results indicated that dietary EO supplementation could affect intestinal microbiota and alleviate intestinal lesions in broilers, which may contribute in controlling C. perffingens infection in broiler chickens.

Thyme oil and thymol abrogate doxorubicin-induced nephrotoxicity and cardiotoxicity in Wistar rats via repression of oxidative stress and enhancement of antioxidant defense mechanisms

This study aimed to assess the preventive effects of thyme oil and thymol on doxorubicin(DOX)-induced renotoxicity,cardiotoxicity,and oxidative stress in Wistar rats.Thyme oil was subjected to GC-MS analysis,which indicated that thymol was the major constituent representing 33.896%.Rats intraperitoneally injected with DOX at a dose of 2 mg/kg b.w./one per week for 7 weeks were co-treated with thyme oil and its major constituent,thymol,at doses 250 and 100 mg/kg b.w./every other day,respectively,by oral gavage for the same period.Thyme oil and thymol markedly ameliorated the raised levels of serum urea,uric acid,and creatinine in DOX-administered rats.They also reduced the elevated activities of serum CK-MB and LDH.Thyme oil was more effective than thymol in decreasing the elevated serum creatinine level and serum CK-MB activity in DOX-administered rats,thereby reflecting its more potent effect on kidney and heart functions.Lipid peroxidation significantly decreased while GSH level and GST and GPx activities significantly increased in kidney and heart of DOX-administered rats treated with thyme oil and thymol.The DOX-induced perturbed kidney histological changes including congestion of glomerulus tuft,inflammatory cells infiltration,protein cast in lumina of the renal tubule,and thickening of the parietal layer of Bowman’s capsule were remarkably ameliorated as a result of treatment with thyme oil and thymol;thyme oil was more effective.In addition,DOX-induced deleterious heart histological alterations,including intramuscular infiltration of inflammatory cells,focal necrosis of cardiac myocytes,and edema,were remarkably reduced by treatment with thyme oil and thymol.Thus,it can be concluded that DOX could induce marked toxicity in kidney and heart,and the treatment with thyme oil or thymol produced potential improvement of kidney and heart function and histological integrity via repression of oxidative stress and enhancement of antioxidant defense mechanisms.

Effects of different amino acid levels and a carvacrol-thymol blend on growth performance and intestinal health of weaned pigs

Background:Over the past years,antibiotic growth promoter had been restricted in animal husbandry production in many countries because of antimicrobial resistance and foodborne antibiotic residues.However,the problems of poor intestinal health and low growth efficiency of piglets have not been solved completely in an antibiotic-free diet,and it is urgent to explore alternatives to antimicrobial growth promoters.Methods:Here,a total of 532 weaned pigs were assigned to one of 4 treatments,the low amino acid(AA)level diet(d 1 to d 14 is 1.35%,d 15 to d 42 is 1.25%)(Low AA),the low AA level diet supplementation with a carvacrol-thymol blend(50 mg carvacrol and 50 mg thymol/kg of diet)(CB)(Low AA+CB),the high AA level diet(d 1 to d 14 is 1.50%,d 15 to d 42 is 1.40%)(High AA),and the high AA level diet supplementation with a CB(High AA+CB),respectively.Then we measured growth performance and intestinal health indicators of weaned pigs.Results:Results showed that high AA level significantly reduced plasma urea nitrogen,plasma Interleukin-6(IL-6)and fecal lipocalin-2 contents(P<0.05),significantly increased the relative abundance of fecal Lactobacillus and Enterococcus,and had a trend to increase the fecal secretory immunoglobulin A(sIgA)and mucin 2(MUC 2)contents(P<0.05)in piglets,thereby alleviating the diarrhea of piglets and reducing the feed conversion ratio(FCR)of piglets during d 1~14 after weaning.Dietary supplementation with CB significantly increased the activity of plasma antioxidant enzymes T-SOD and GSH-px(P<0.05),while significantly reduced plasma malondialdehyde(MDA),plasma interleukin-1β(IL-1β),plasma endotoxin and D-lactic acid contents(P<0.05).Meanwhile,CB significantly decreased fecal lipocalin-2 contents and the abundance of fecal Escherichia coli(P<0.05).Thus,we hypothesis that dietary supplementation with CB significantly increased the average daily gain(ADG)of piglets(P<0.05)during d 1~14 after weaning through promoting intestinal health.Conclusion:These results suggest that high AA level and dietary supplementation with CB improved the growth performance of weaned pigs in an antibiotic-free diet by improving AA metabolism and intestinal antioxidant capacity.

Phylogenetic analysis and protective effects of thymol and its chromatographic fractions from a novel wild mushroom in combating oxidative stress

Mushrooms are good sources of phytochemicals that have antioxidant and anti-proliferative effects.This study identifi ed a unique isoform of 18S rRNA gene(864 bp)from a novel wild mushroom(SMK-1)(GenBank accession number:SUB3267363).Thin layer chromatographic(TLC)profiling of the methanolic extract of the dried mushroom fruiting bodies of SMK-1 revealed the presence of phenolic and fl avonoid fractions with retention factor(Rf)values of 0.955 and 0.927 respectively.The GC/MS chromatograms of the SMK-1 methanolic extract identifi ed the main bioactive compound was phenol,5-methyl-2-(1-methylethyl)(74.00%)(thymol).The radical scavenging activity for the fl avonoid fraction was greater than the phenolic fractions(Rf–phenolics fractions>Rf–fl avonoid fractions)with the antioxidant activity more than that of standard ascorbic acid.Also,the phenolic and flavonoid fractions of SMK-1 expressed cytotoxic effects in HeLa cells with IC50 values ranging from 5μg/mL to 80μg/mL in a dose-dependent manner.This present research highlights the presence of high thymol concentration in a novel wild mushroom that has antioxidant and anti-poliferative potential with therapeutic benefi ts.The application of thymol natural products from novel mushroom SMK-1 as nutrition supplements could inhibit oxidative stress triggered by numerous pathologies that may pave the way to develop a new therapeutic natural drug.

New Thymol Derivate from Centipeda minima

1 Introduction Centipeda minima（Compositae） is an annual herbaceous plant found in moist places throughout the plains mainly in the southern regions of the People＇s Republic of China, Eastern tropical Asia, Australia and the Pacific Islands. It is a commonly used Chinese folk medicine for colds, whooping cough, nasal allergy, malaria and asthma. A number of sesquiterpene lactones, flavonoids and triterpenes have previously been isolated from C. minima. During our study on searching for biological active components from this plant,

Thymol Protects against Aspergillus Fumigatus Keratitis by Inhibiting the LOX-1/IL-1βSignaling Pathway

Objective To explore the anti-inflammatory effects and mechanisms of action of thymol in Aspergillus fumigatus(A.fumigatus)keratitis.Methods The minimum inhibitory concentration of thymol against A.fumigatus was detected.To characterize the anti-inflammatory effects of thymol,mouse corneas and human corneal epithelial cells were pretreated with thymol or dimethyl sulfoxide(DMSO)before infection with A.fumigatus spores.Slit-lamp microscopy,immunohistochemistry,myeloperoxidase detection,quantitative real-time polymerase chain reaction,and Western blotting were used to assess infection.Neutrophil and macrophage recruitment,in addition to the secretion of LOX-1 and IL-1β,were quantified to evaluate the relative contribution of thymol to the inflammatory response.Results We confirmed that the growth of A.fumigatus was directly inhibited by thymol.In contrast with the DMSO group,there was a lower degree of inflammation in the mouse corneas of the thymol-pretreated group.This was characterized by significantly lower clinical scores,less inflammatory cell infiltration,and lower expression of LOX-1 and IL-1β.Similarly,in vitro experiments indicated that the production of LOX-1 and IL-1βwas significantly inhibited after thymol treatment,in contrast with the DMSO-pretreated group.Conclusion Our findings demonstrate that thymol exerted a direct fungistatic activity on A.fumigatus.Furthermore,thymol played a protective role in fungal keratitis by inhibiting LOX-1/IL-1βsignaling pathway and reducing the recruitment of neutrophils and macrophages.

Catalytic ozonation of thymol in reverse osmosis concentrate with core/shell Fe_3O_4@SiO_2@Yb_2O_3 catalyst:Parameter optimization and degradation pathway

In this work, a novel catalyst of Fe_3O_4@SiO_2@Yb_2O_3 was prepared and the degradation of thymol in reverse osmosis concentrate using ozonation was explored. The operational parameters, such as ozone dosage(8–48 mg·min^(-1)),initial thymol concentration(20–100 mg·L^(-1)), initial pH value(3–11), and catalyst Fe_3O_4@SiO_2@Yb_2O_3dosage(0.2–1.0 g), were studied focusing on the thymol degradation and COD removal. The results indicated that the increase in ozone dosage, initial p H value, and Fe_3O_4@SiO_2@Yb_2O_3dosage accelerated the thymol degradation and COD removal, while the increase in initial thymol concentration hampered the effect of ozonation. A pathway of thymol degradation by catalytic ozonation was proposed based on the intermediates detected by gas chromatography-mass spectrometer and ion chromatography. This paper can provide basic data and technical alternative for pollutant removal from reverse osmosis concentrate by ozonation.

Synthesis of 5-methyl-2-(2,4,4,7-tetramethylchroman-2-yl) Phenol as an Impurity in Thymol

[Objectives] To optimize the preparation process of 5-methyl-2-(2,4,4,7-tetramethylchromanyl) phenol(impurity C) and the liquid phase determination method of the impurity, and to provide an important basis for the establishment of material methods and quality control of thymol. [Methods] The 4,7-dimethylcoumarin as the starting material was hydrolyzed by potassium hydroxide to obtain the substance II 5-methyl-2-(1-propylene-2-yl) phenol, and then purified and treated with hydrochloric acid to obtain a pale yellow solid. High-purity main peak was obtained by high-performance liquid phase method, and it was identified as impurity C by ~1H-NMR measurement and spectrum analysis. [Results] After the method was optimized, the synthesis route to the impurity C was simple, and the purity of impurity C was high. The obtained impurity C was confirmed by ~1H-NMR to be a compound 5-methyl-2-(2,4,4,7-tetramethylchromanyl) phenol. The liquid phase detection method was successfully established to identify the compound. [Conclusions] The optimized method is easy to control and the impurity C has high purity and it is expected to provide quality assurance for the study of related substances in the quality control of thymol.

Optimisation of the Postharvest Treatment with Thymol to Control Mango Anthracnose

Anthracnose, caused by the fungus called Colletotrichum gloeosporioides, is the main postharvest disease that affects mango production on Reunion Island. Fruits for the export market are always treated with chemicals. The use of chemical treatment is not in adequation with consumer expectations, and the increasing emergence of fungicide-resistant isolates promotes the development of alternatives methods. The principal objective of this work was to use antimicrobial properties of thymol as an alternative postharvest treatment on mango. Thymol diluated in a penetrating agent solution was effective on mango anthracnose. At a concentration of 0.025%, Thymol limited necrosis development due to pathogens during fruit storage. This treatment can stimulate some of polyphenols biosynthesis involved in the fruit resistance to postharvest disease, particularly thesynthesis of gallic acid and resorcinol. With this final concentration of 0.025% thymol, the treatment did not affect fruit maturation and quality, especially the peel colour and sugar content. Importantly, the treatment did not show any detectable effect on organoleptic qualities of the fruit.

Chemical Composition and Biological Significance of Thymol as Antiparasitic

Thymol is one of the most important phytochemical components because of its pharmacological and bioactive potential effects. This review focuses particularly on thymol as an alternative natural antiparasitic with potential use in the pharmaceutical industry. This is in line with the preferences of the natural products for treatment being safer and without side effects. The biosynthesis pathways of thymol and carvacrol have been discussed, and mechanism of action of thymol on parasites. Studies on thymol confirmed the activity of thymol as anti-parasite against anthelmintic, Trypanosoma ssp., Toxoplasma gondii, Leishmania spp., Plasmodium falciparum, Giardia duodenalis, Eimeria ssp., Cryptosporidium baileyi and Cryptosporidium galli.

Characterization and Adsorption Study of Thymol on Pillared Bentonite

Pillared clay (PILC) was prepared from Moroccan clay and characterized, and its aqueous thymol adsorption capacities were studied using a batch equilibrium technique. So, we tested the encapsulation of thymol by aluminum pillared clay (PILC). The PILCs displayed a total surface area of 270 m2/g, a total pore volume of 0.246 cm3/g and an average pore diameter of 8.9 A, which corresponds to the size of Al13 forming the pillars between the clay layers. The adsorption capacity shown by the PILCs for thymol from water is close to 319 mg?g-1 for low solid/liquid ratio (0.2%). This result suggests that the PILCs have both hydrophobic and hydrophilic characteristics, as a result of the presence of silanol and siloxane groups formed during the pillaring and calcination of the PILCs. The experimental data were analyzed by the Freundlich and the Langmuir isotherm types for low values of equilibrium concentration. The rise of the isotherm in this range of concentrations was related to the affinity of thymol for clay sites, and the equilibrium data fitted well with the Freundlich model with maximum adsorption capacity of 319.51 mg/g for a ratio RS/L = 0.2%. Pseudo-first and pseudo-second-order kinetic models were tested with the experimental data and pseudo-first order kinetics was the best for the adsorption of thymol with coefficients of correlation R2 ≥0.986, and the adsorption was rapid with 90% of the thymol adsorbed within the first 20 min.

Phyto-Fungicides: Structure Activity Relationships of the Thymol Derivatives against <i>Rhizoctonia solani</i>

Thymol, the key component of the thyme oil and its derivatives were evaluated for their structure activity relationship as fungicide against Rhizoctonia solani. Since plant-based chemicals are considered as “Generally Recognized as Safe” (GRAS) chemicals, there is great potential to use those and synthetic derivatives against R. solani and other fungal pathogens, in vitro, and in the?greenhouse or field conditions. Among the six thymol derivatives evaluated, thymol acetate was considered as the most suitable commercially viable plant-based fungicide due to its superior efficacy as well as lowest residue.

Influence of Abiotic Elicitors on Accumulation of Thymol in Callus Cultures of Origanum vulgare L.

Callus cultures of Origanum vulgare L. were established from leaf discus on Murashige and Skoog （MS） medium containing different levels of growth regulators, i.e., 2,4-Dichlorophenoxyacetic acid （2,4-D）, Naphthalene acetic acid （NAA）, Benzyl Adenine （BA） and Kinetin （Kn） and incubated under dark condition. Callus tissues were employed to study the influence of abiotic elicitors on the production of thymol. Constant weights of callus （300 mg） were cultured on accumulation medium treated separately with each one of elicitors used （50 g/L sucrose, 200 mg/L NaC1 and 50 or 100 mg/L proline）. The fresh and dry weights of callus were recorded after six weeks. The result indicated that maximum production of fresh and dry callus weight were 1,014 mg and 46.20 mg respectively achieved at 0.5 mg/L 2,4-D and 3 mg/L BA adding to the medium. Dry callus tissues were extracted with 70% methanol and analyzed by HPLC to determine the concentrations of thymol. The addition of abiotic elicitors to MS medium caused significant reduction in fresh weight of callus compared with control treatment. The concentration of thymol in the callus cultured on control treatment was 146.6 ppm. The data showed that 50 or 100 mg/L proline produced the highest yield of thymol 181.48 ppm and 174.58 ppm respectively, followed by sucrose 162.9 ppm, whereas the treatment with NaCI caused reduction in thymol concentration to percentage of 50.56% compared with the control.

松材线虫胁迫对5种松树的代谢组共性表达

为研究松树在松材线虫胁迫下的分子防御机制,分别选取15~20年生的辽宁抚顺的油松(LY)、辽宁抚顺的红松(LH)、山东威海的赤松(SC)、山东威海的黑松(SH)、湖南长沙的马尾松(HM)5种代表性松树作为研究对象,运用液相色谱-质谱联用技术的非靶向代谢组学,将以上5种松树分为健康组和感病组,分别对5组松树样本的差异代谢物分布情况、差异代谢物的共性特征、共有差异代谢物的表达显著性、代谢通路富集分布情况、差异性代谢通路的共性特征等进行研究。结果表明:5种松树感染松材线虫后的代谢产物在苯和取代衍生物、羧酸及其衍生物、脂肪酰基、酚类、孕烯醇酮脂类、类固醇及其衍生物、其他类等7类化合物中分布较为集中;HM、LH、LY和SC,HM、LY、SC和SH这两种组合,只有1种共有的显著性差异代谢物,分别是百里酚和6-姜酮酚,5种松树以及剩下的其他4种松树的组合都没有共有的显著性差异代谢物;HM、LY、SC和SH感染松材线虫后,6-姜酮酚表达量显著升高,LH感染松材线虫后,6-姜酮酚表达量无显著性差异;HM、SC、LY和LH感染松材线虫后,百里酚表达量显著升高,SC感染松材线虫后,百里酚表达量无显著性差异;HM、LH、LY、SC、SH分别富集到51、55、46、71、43条差异显著的信号通路,5种松树共有的差异显著的信号通路共有19条,主要反映在植物的抗逆相关信号通路上,包括花生四烯酸代谢、亚油酸代谢、苯丙烷生物合成、多种氨基酸代谢等。

Thymol ameliorates ammonium toxicity via repressing polyamine oxidase-derived hydrogen peroxide and modulating ammonium transporters in rice root

Background:Ammonium is an indispensable nutrient for crop growth,but anoxic conditions or inappropriate fertilizer usage result in the increase in ammonium content in soil.Excessive ammonium causes phytotoxicity.Thymol is a kind of natural phenolic compound with anti-microbial properties.However,little is known about the role of thymol in modulating plant physiology.Here we find the novel role of thymol in protecting rice from ammonium toxicity.Results:Thymol remarkably rescued rice seedlings growth from ammonium stress,which may resulted from the attenuation of reactive oxygen species(ROS)accumulation,oxidative injury,and cell death in both shoots and roots.Polyamine oxidase(PAO)metabolizes polyamines to produce ROS in plants in response to stress conditions.Thymol blocked ammonium-induced upregulation of a set of rice PAOs,which contributed to the decrease in ROS content.In rice seedlings upon ammonium stress,thymol downregulate the expression of ammonium transporters(AMT1;1 and AMT1;2);thymol upregulated the expression of calcineurin B-like interacting protein kinase 23(CIPK23)and calcineurin B-like binding protein 1(CBL1),two negative regulators of AMTs.This may help rice avoid ammonium overload in excessive ammonium environment.Correlation analysis indicated that PAOs,AMTs,and CBL1 were the targets of thymol in the detoxification of excessive ammonium.Conclusion:Thymol facilitates rice tolerance against ammonium toxicity by decreasing PAO-derived ROS and modulating ammonium transporters.Such findings may be applicable in the modulation of nutrient acquisition during crop production.

百里香酚对犊牛源生物被膜阳性金黄色葡萄球菌耐药性的消除作用

为了了解内蒙古地区犊牛病料中生物被膜阳性金黄色葡萄球菌的流行情况、耐药情况及百里香酚对生物被膜阳性金黄色葡萄球菌耐药性的消除作用。本试验采用生化鉴定和PCR方法,对采集到的104份犊牛病料进行金黄色葡萄球菌的分离鉴定;采用K-B法检测了金黄色葡萄球菌分离株对18种抗菌药物的敏感性;采用改良结晶紫染色法测定分离株的生物被膜形成能力;选取2株生物被膜强阳性菌株,采用微量肉汤稀释法测定百里香酚对分离株的最小抑菌浓度,并进行百里香酚耐药性消除试验。结果显示,在104份犊牛病料中共分离鉴定获得43株金黄色葡萄球菌。药敏试验结果显示,金黄色葡萄球菌分离株对氨苄西林、头孢西丁、卡那霉素、复方新诺明和红霉素5种抗菌药物的耐药率达到50.0%以上;74.4%(32/43)的分离株为多重耐药株。生物被膜形成能力强、中、弱和无生物被膜形成能力的分离株分别占比23.3%(10/43)、16.3%(7/43)、32.6%(14/43)和27.9%(12/43);生物被膜阳性株中83.9%(26/31)为多重耐药株。百里香酚对2株生物被膜强阳性株的最小抑菌浓度均为256 mg/mL,经百里香酚处理后均恢复了对头孢噻肟的敏感性。结果表明,百里香酚对生物被膜阳性金黄色葡萄球菌具有一定的耐药消除作用。

麝香草酚控制核盘菌侵染不结球白菜效应研究

核盘菌可侵染多种蔬菜,造成蔬菜采后品质下降,筛选高效安全的天然保鲜剂是控制核盘菌侵染的有效手段。通过离体和活体接种试验,研究了植物源天然化合物麝香草酚对核盘菌侵染青菜的控制效应。结果表明:20、40、60μg/mL麝香草酚处理后的菌丝鲜重分别比对照组显著下降了33.8%、53.7%、88.1%;菌丝干重分别比对照组下降了24.5%、53.7%、82.9%;麝香草酚处理导致核盘菌菌丝畸形、皱缩、细胞死亡,可能与菌丝细胞膜损伤有关,表现为相对电导率和丙二醛含量上升;麝香草酚还可诱导菌丝细胞甘油含量显著上升,发生渗透胁迫;50μg/mL麝香草酚处理青菜可显著抑制核盘菌在叶片上的侵染;在接种核盘菌的青菜叶片中,麝香草酚诱导特异型抗性基因BrMPK3和BrMPK4的表达量上调,并显著提升青菜品质(包括叶绿素、蛋白质、可溶性糖、维生素C含量提升)。麝香草酚可有效控制核盘菌对青菜的侵染,表现为抑菌效应和诱导寄主抗性效应。

姜酚和百里香酚对白羽肉鸡小肠形态结构和屏障功能的影响

[目的]本试验旨在研究日粮添加姜酚、百里香酚及其组合对白羽肉鸡小肠形态、免疫功能及肠道屏障的影响。[方法]将200只1日龄AA白羽肉鸡随机分为4组,每组5个重复,每个重复10只,试验期为42 d。4个处理组如下:对照组(Con组,基础日粮)、姜酚组(Gin组,基础日粮+60 mg·kg^(-1)姜酚)、百里香酚组(Thy组,基础日粮+30 mg·kg^(-1)百里香酚)及姜百组(Gin+Thy组,基础日粮+30 mg·kg^(-1)姜酚+15 mg·kg^(-1)百里香酚)。在试验期第42天,采集肉鸡的空肠和回肠制作切片并观察,取空肠和回肠黏膜以测定免疫球蛋白含量、细胞因子含量、抗氧化酶活性、紧密连接和抗氧化相关基因表达。[结果]与对照组相比,姜百组肉鸡回肠绒毛高度(VH)有增加的趋势(P=0.063),绒毛高度/隐窝深度(V/C)值显著提高(P<0.05);姜百组肉鸡空肠和回肠黏膜中分泌性免疫球蛋白A(sIgA)含量显著提高(P<0.05),空肠黏膜中白介素6(IL-6)和干扰素γ(IFN-γ)含量以及回肠黏膜中IL-6和白介素1β(IL-1β)含量显著降低(P<0.05);姜百组肉鸡空肠和回肠黏膜中总抗氧化能力(T-AOC)和谷胱甘肽过氧化物酶(GSH-Px)活性显著升高(P<0.05);姜百组肉鸡空肠黏膜中核因子E2相关因子2(Nrf2)、血红素加氧酶1(HO-1)、谷胱甘肽过氧化物酶(GPX4)和回肠黏膜中Nrf2、超氧化物歧化酶1(SOD1)、GPX4的mRNA相对表达量显著升高(P<0.05),空肠和回肠黏膜中的Occludin mRNA相对表达量显著增加(P<0.05)。[结论]日粮添加姜酚和百里香酚组合可以提高肉鸡的抗氧化能力和免疫功能,并通过改善肠道形态和肠道屏障促进肠道健康。

百里香酚单向输水抑菌垫制备及其对冷鲜马肉保鲜研究

为解决冷鲜马肉在贮藏过程中发生汁液流失,导致冷鲜马肉发生腐败变质的问题,该研究通过静电纺丝技术,制备出单向输水抑菌垫并应用于冷鲜马肉的保鲜实验中。通过扫描电镜、傅里叶红外光谱、缓释性能、单向输水性能和抗菌性能评价该抑菌垫对冷鲜马肉的保鲜效果。结果表明,百里香酚被成功包埋于上层纤维膜中并且具有缓释作用,对大肠埃希氏菌、金黄色葡萄球菌具有明显的抑菌效果[抑菌圈直径为(24.32±0.72)mm],水可以自发地从疏水层到达亲水层并且被吸收。将该抑菌垫应用于冷鲜马肉的贮藏实验中,单向输水抑菌垫对于马肉中菌落总数值、挥发性盐基氮(total volatile basic nitrogen,TVB-N)值的上升均具有明显地延缓作用,并且可以将马肉货架期延长6 d。该抑菌垫可以控制微生物生长繁殖所需水分并抑制微生物繁殖,因此,该抑菌垫可以有效延长冷鲜肉的货架期,为冷鲜肉的贮藏保鲜提供了一种新的方向。

麝香草酚破坏小肠结肠炎耶尔森氏菌细胞膜并抑制其生物被膜的形成研究

小肠结肠炎耶尔森氏菌(Yersinia enterocolitica)是食品工业中常见的致病菌,其生物被膜是主要的污染源.为了阐明麝香草酚对Y.enterocolitica的抑制机制,本研究首先测定了最小抑制浓度(MIC)、最小抑制生物被膜浓度(MBIC)和最小清除生物被膜浓度(MBEC),随后检测了细胞膜电位以及细胞内ATP和pH值的变化,最后在激光共聚焦显微镜(CLSM)、场发射扫描电子显微镜(FEGSEM)和光学显微镜下,直接观察了麝香草酚引起的细胞膜损伤及其对生物被膜的抑制作用.结果显示,麝香草酚对Y.enterocolitica的MIC为0.156 25 mg/mL,MBIC仅为1/16 MIC,改变了细胞形态并导致胞内ATP降低、膜去极化和pH下降.旨在探索麝香草酚抑制Y.enterocolitica及其生物被膜的机理,从而为麝香草酚能否作为植物源天然防腐剂提供更多参考.