The effects of steam explosion (SE) and enzymatic/microbial treatments on ruminal utilization of corn stover (CS) were evaluated using batch culture and in situ methods. CS was subjected to a 2 × 3 factorial experimental design comprising six treatment groups: 2 processing (raw CS and SE processed CS (SECS)) combined, respectively, with 3 additives (no additives, Lactobacillus plantarum (Lac) and laccase). In vitro rumen fermentation characteristics, morphological structure, lignocellulosic composition, cellulose accessibility, and fiber degradability were evaluated. The results revealed that the SE processing increased (P < 0.001) CP content and decreased (P < 0.001) the content of NDF, ADF and ADL compared to the raw CS. The lignocellulosic microstructure of the CS was damaged or broken by both SE and Lac/laccase treatments. The SE processing versus raw CS also increased (P < 0.001) in vitro gas production, concentration of total volatile fatty acid, proportion of propionate and decreased (P = 0.05) ratio of acetate to propionate and methane production. The SE alone or combined with the Lac or laccase addition increased (P < 0.01) in situ rumen degradation kinetics of dry matter and NDF. The relative abundances of the rumen-adhering genera on CS, namely Butyrivibrio, Lachnospiraceae and Prevotella, increased (P < 0.05) with the combination of SE with Lac or laccase versus the other treatments. These results demonstrated that either SE processing or adding Lac and laccase on the fermentation of CS may be a promising strategy to improve its rumen utilization. A potential additive effect by combining SE processing and Lac fermentation is worth to be further investigated.

This study was to evaluate the effects of steam explosion (SE), Lactobacillus plantarum (Lac) or laccase fermented Corn stover (CS) and their interaction on in vitro gas production (GP), ruminal fermentation, and in situ ruminal degradation kinetics and microbial adhesion of CS. The experiment was a 2×3 factorial arrangement of treatments with CS and CS treated with SE (SECS) to be fermented by adding no Lac/laccase, Lac or laccase. The results revealed that The SE processing increased (P < 0.001) CP content and decreased (P < 0.001) the content of NDF, ADF and ADL compared to the untreated CS. Lac/laccase and SE treatment can broke the lignocellulosic structures. SE processing increased (P < 0.001) the GP, concentration of total VFA, proportion of propionate, and ammonia concentration, decreased (P = 0.05) ratio of acetate to propionate and methane production. The SE and Lac or laccase treatment increased (P < 0.01) in situ rumen degradation kinetics of DM and NDF. The relative abundances of the rumen-adhering genera on CS, namely Butyrivibrio, Lachnospiraceae and Prevotella, which conducive to fiber degradation, increased (P < 0.05) with the SE+Lac/laccase treatment than those of the other treatments. These results demonstrated that either SE processing or adding Lac and laccase on fermentation of CS is an effective nutritional strategy to improve rumen digestibility of CS. A potential additive effect by combining SE processing and Lac fermentation is worth to be further investigated.

BACKGROUND:Doxorubicin (DOX) is a widely used anthracycline antibiotic for the treatment of breast cancer, liver cancer, lymphoma, and other malignant tumors. However, its clinical application is limited by the side effects and drug resistance. Astragalus injection has been combined with DOX in the treatment of cancer, which improves the curative effect and reduces drug resistance. This study investigated the interaction between DOX and Astragalus injection and elucidated the potential mechanism. METHODS:The pharmacokinetics of DOX injection (7 mg/kg, intraperitoneal injection) with or without Astragalus injection (4.25 mL/kg/day for 14 days, intraperitoneal injection) were investigated in plasma from male Sprague-Dawley rats (n = 6) by UPLC-MS/MS. The group without the Astragalus injection was set as the control group. Additionally, the effects of Astragalus injection on CYP450 enzyme activities were assessed using a rat liver microsome incubation system with cocktail probe drugs. RESULTS:Astragalus injection significantly increased the Cmax (2090.01 ± 99.60 vs. 5262.77 ± 111.15 ng/mL) and AUC0-t (1190.23 ± 104.43 vs. 3777.27 ± 130.55 μg/L × h) and prolonged the t1/2α (0.09 ± 0.02 vs. 0.14 ± 0.04 h) of DOX. Astragalus injection significantly inhibited the activity of CYP1A2, CYP2C9, CYP2E1, and CYP3A4, and enhanced the activity of CYP2D1 with a metabolic elimination rate of 30.11 ± 2.67% vs. 19.66 ± 3.41%, 35.95 ± 2.57% vs. 23.26 ± 3.57%, 13.43 ± 2.56% vs. 9.06 ± 2.51%, 47.90 ± 6.30% vs. 25.87 ± 2.55%, 17.62 ± 1.49% vs. 24.12 ± 2.91%, respectively (p < 0.05). CONCLUSION:The co-administration of DOX and Astragalus injection alters the systemic exposure of DOX by affecting the metabolism of DOX and the activity of CYP450 enzymes. These findings highlight the importance of drug-drug interactions when combining Astragalus injection with DOX and provide a basis for optimizing combination therapies to address DOX resistance and toxicity.

Focusing on the contents of phenolic compounds such as tannins and anthocyanins, this study aims to construct prediction models for phenolic compound concentrations in wine grapes Cabernet Sauvignon and to identify key characteristic wavelengths associated with these contents. Diffuse reflectance spectra of wine grapes Cabernet Sauvignon were collected using a portable fiber-optic spectrometer. Principal component analysis (PCA) was employed to eliminate outliers, and the SPXY algorithm was applied to divide the dataset into a calibration set (n = 145) and a prediction set (m = 49). Various preprocessing methods and their combinations-including Savitzky-Golay convolution smoothing (SG), multiplicative scatter correction (MSC), standard normal variate (SNV), and standardization (SS)-were compared to determine the optimal preprocessing strategy for different phenolic compounds, yielding the best preprocessed spectral data. Subsequently, characteristic wavelengths were extracted using competitive adaptive reweighted sampling (CARS), successive projections algorithm (SPA), and uninformative variable elimination (UVE). Through comparative analysis, the most effective wavelength selection method and the optimal number of characteristic wavelengths were identified, and partial least squares regression (PLSR) models for tannins and anthocyanins contents were established. The results demonstrated that for tannins, the model combining SG-SNV-SS preprocessing with the CARS algorithm achieved the best performance (Rc2 = 0.9964, Rp2 = 0.9939, RPD = 3.7653), with seven optimal characteristic wavelengths identified at 422.64 nm, 828.86 nm, 948.92 nm, 993.22 nm, 1003.17 nm, 1122.10 nm, and 1122.94 nm. For anthocyanins, the model based on raw spectral data combined with the CARS algorithm yielded the best results (Rc2 = 0.9899, Rp2 = 0.9768, RPD = 6.5591), with six optimal characteristic wavelengths identified at 440.35 nm, 580.76 nm, 632.38 nm, 777.21 nm, 898.61 nm, and 1013.96 nm. The constructed models effectively screened key characteristic wavelengths associated with tannins and anthocyanins contents, enabling accurate prediction of phenolic compounds in wine grapes. This research provides a solid theoretical basis and technical support for the development of portable instruments and the selection of light source devices.

Essential oils from oregano (OEO) and cinnamon (CEO) have been reported an excellent antibacterial activity, but their synergistic antibacterial effect is rarely studied. In this study, the chemical compositions of OEO, CEO and mixed OEO with CEO (MEO) and their antibacterial activities were analyzed, the mode of MEO action against enterotoxigenic Escherichia coli K99 (ETEC K99) were investigated. Results showed that MEO had the synergistic antibacterial effect, which was proven by fractional inhibitory concentration index of 0.375. The inhibition zone diameter measured varying with volume ratio of OEO and CEO showed that the best synergistic effect was at a ratio 2:8. Meanwhile, the antibacterial mechanism of MEO demonstrated that the MEO changed the morphology of ETEC K99 by scanning and transmission electron microscopy, and disrupted the cell membrane integrity that were proved by the leakage of intracellular nucleic acid and lower alkaline phosphatase activity of ETEC K99. In addition, the MEO also inhibited DNA biosynthesis, biofilm formation and scavenged mature biofilm of ETEC K99. These results confirm the synergistic effect on improvement of antibacterial activity and elucidate a variety of mechanisms through which the ETEC K99 was inactivated, and support the application of MEO to against ETEC K99.

The purpose of this study was to investigate the effects of early castration and eucalyptus oil (EUC) supplementation on dry matter intake (DMI), growth performance and immune response of Holstein calves. Fifty-six Holstein male calves at the age of 52 d (initial body weight [BW], 63.5 ± 5.27 kg) were used. The animals were blocked by BW and randomly assigned into 1 of the 4 treatments in a randomized complete block design with a 2 (no castration vs. castration) × 2 (without vs. with EUC) factorial arrangement of treatments. The treatments were: uncastrated calves fed without EUC (CON), and with 0.5 g/d EUC (EUC), or castrated steers fed without EUC (Castrated), and with 0.5 g/d EUC (Castrated + EUC). The experiment was 8 weeks long including pre-weaning and post-weaning (weaned at the age of d 72). The EUC × Castration interactions were not significant for DMI, growth performance, nutrient digestibility and immune response. The castration did not affect the DMI, final BW, average daily gain (ADG) or feed efficiency, except that the ADG was greater for uncastrated than castrated steers at post-weaning. Supplementation of EUC increased DMI pre-weaning and post-weaning, and increased ADG of weaned calves. Digestibility in the total digestive tract was not affected by castration (except for organic matter digestibility), whereas adding EUC improved the digestibility of DM, acid detergent fiber and crude protein. Blood concentration of interleukin-6 at d 94 was decreased by feeding EUC. These results indicate that the EUC could be fed to either intact or castrated dairy calves to promote growth and health post-weaning; the castration before weaning may reduce ADG and cause inflammatory stress without affecting feed intake or feed efficiency.

断奶应激由环境变化、饲粮转换以及消化和免疫系统发育不完全引起,会导致犊牛生长受阻并增加腹泻的风险,影响生产效率.研究断奶应激对犊牛的影响和作用机理及其营养调控措施对生产具有重要意义.本文从胃肠道和免疫功能以及生长性能阐述断奶应激对犊牛的影响及其作用机理,并提出营养调控措施,以期为未来的犊牛生产应用提供理论依据.

Citrus Medica limonum essential oil (LEO) has been reported to have antibacterial and anti-inflammatory activities, but its protective effect in the intestine remains unknown. In this study, we researched the protective effects of LEO in relation to intestinal inflammation induced by E. coli K99. The mice were pretreated with 300, 600, and 1200 mg/kg LEO and then stimulated with E. coli K99. The results showed that E. coli K99 caused immune organ responses, intestinal tissue injury, and inflammation. LEO pretreatment dose-dependently alleviated these changes by maintaining a low index in the thymus and spleen and producing a high content of immunoglobulin A, G, and M (IgA, IgG, and IgM) and low content of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), and interleukin-6 (IL-6). Intestinal integrity as a consequence of the LEO pretreatment may be related to the high mRNA expression of intestinal trefoil factor (ITF) and the low mRNA expression of transforming growth factor-β1 (TGF-β1). Conclusively, an LEO pretreatment can alleviate E. coli K99-induced diarrhea, immune organ response, and body inflammation in mice by reducing the levels of inflammatory cytokines and improving the levels of immunoglobulin, and the intestinal integrity remained highest when maintaining the high mRNA expression of ITF and keeping the mRNA expression of TGF-β1 low in the intestinal tissue.

Background Doxorubicin (DOX) is an antitumor antibiotic widely used in the treatment of breast cancer, liver cancer, lymphoma and other malignant tumors. However, its clinical application is limited by the side effects and drug resistance. Astragalus injection has been combined with DOX in the treatment of cancer, which can improve the curative effect and reduce drug resistance. This study investigated the interaction between DOX and Astragalus injection and elucidated the potential mechanism. Methods The pharmacokinetics of DOX injection (7 mg/kg) with or without Astragalus injection (4.25 mL/kg/day for 14 days) were investigated in male Sprague-Dawley rats (n = 6) by UPLC-MS/MS. The group without the Astragalus injection was set as the control group. Additionally, Sprague-Dawley rat liver microsomes incubation systems were employed to assess the effects of Astragalus injection on CYP450 enzymes. Results Astragalus injection significantly increased the Cmax (2090.01 ± 99.60 vs. 5262.77 ± 111.15 ng/mL) and AUC0-t (1190.23 ± 104.43 vs. 3777.27 ± 130.55 µg/L × h) and prolonged the t1/2α (0.09 ± 0.02 vs. 0.14 ± 0.04 h) of DOX. Astragalus injection significantly inhibited the activity of CYP1A2, CYP2C9, CYP2E1, and CYP3A4, and enhanced the activity of CYP2D1 with a metabolic elimination rate of 30.11 ± 2.67% vs 19.66 ± 3.41%, 35.95 ± 2.57% vs 23.26 ± 3.57%, 13.43 ± 2.56% vs 9.06 ± 2.51%, 47.90 ± 6.30% vs 25.87 ± 2.55%, 17.62 ± 1.49% vs 24.12 ± 2.91%, respectively (p < 0.05). Conclusions The co-administration of DOX and Astragalus injection alters the system exposure of DOX, possibly by affecting the metabolism of DOX by affecting the activity of CYP450 enzymes. Further clinical studies could be carried out according to the investigation.

Escherichia coli K99 (E. coli K99) is one of the important pathogenic bacteria in calf production causing massive loss every year, and Lactobacillus acidophilus (L. acidophilus) is an important probiotic in the gut. Essential oils in Citrus have selective antibacterial activity and the capacity to be an alternative to antibiotics. In this study, we analyzed the chemical component of Citrus Medica Limonum essential oil (LEO) and D-limonene, & beta;-pinene, and & gamma;-terpinene by GC-MS, then compared their selective antibacterial activities against E. coli K99 and L. acidophilus and investigated the antibacterial mechanism of LEO. The principal component of LEO, D-limonene, & beta;-pinene, and & gamma;-terpinene were D-limonene (47.19%), D-limonene (77.94%), & beta;-pinene (93.52%) and & gamma;-terpinene (89.27%) respectively. The MIC and MBC of LEO against E. coli K99 were 5 mg/mL and 10 mg/mL, while against L. acidophilus were 80 mg/mL and 160 mg/mL, which showed its best selective antibacterial activity among four EOs. LEO damaged the cell membrane structure, leading to the leakage of intracellular proteins and nucleic acids of both bacteria. Moreover, LEO improved the cell-surface hydrophobicity of both bacteria and decreased the soluble protein content of E. coli K99. In conclusion, LEO has selective antibacterial activity and the potential to be applied in calf feed.

The purpose of this study was to compare the antioxidant activity of litsea cubeba oil (LCO), cinnamon oil (CO), anise oil (AO), and eucalyptus oil (EUC) in vitro. The chemical compositions of the essential oils (EOs) were analyzed using gas chromatography-mass spectrometry (GC-MS). The antioxidant activity of the four EOs was evaluated through scavenging DPPH free radicals, chelating Fe2+, scavenging hydroxyl free radicals, and inhibiting yolk lipid peroxidation. The results showed that the major compounds found in LCO, CO, AO, and EUC are citral (64.29%), cinnamaldehyde (84.25%), anethole (78.51%), and 1,8-cineole (81.78%), respectively. The four EOs all had certain antioxidant activity. The ability to scavenge DPPH radical was ranked in the order of LCO > CO > AO > EUC. The hydroxyl radical scavenging ability was ranked in the order of EUC > CO > LCO > AO. The chelating Fe2+ capacity was ranked in the order of EUC > AO > CO > LCO. The yolk lipid peroxidation inhibition ability was ranked in the order of CO > AO > EUC > LCO. In different antioxidant activity assays, the antioxidant activity of the EOs was different. It was speculated that the total antioxidant activity of an EO may be the result of the joint action of different antioxidant capacities.

柑橘类植物精油(CEOs)是从柑橘类植物中提取的芳香类混合物,其主要活性成分为D-柠檬烯(D?limonene),具有广泛的生物活性,包括抗菌、抗氧化和抗炎等.CEOs具有选择性抗菌活性,在动物生产中具有非常重要的应用价值.不同的CEOs具有不同的抗菌活性,研究其抗菌机制也具有非常重要的意义.本文着重介绍了CEOs的化学组成、抗菌活性及其抗菌作用机制,为其在畜牧生产中的应用奠定基础.

Inflammatory diseases are a major threat to public health. Natural plant essential oils (EOs) possess anti-inflammatory and anti-oxidative activities. The objective of this study was to investigate the anti-inflammatory effect and mode of action of lemon essential oil (LEO), and its main active component, d-limonene, with different doses on intestinal inflammation of mice. Sixty-four 5-week-old male balb/c mice weighing 22.0 ± 1.5 g were randomly assigned into one of 8 treatments (n = 8/treatment), including normal saline group (NS), Escherichia coli (E. coli) group, and either LEO and d-limonene essential oil (DEO) group supplemented at 300, 600, and 1,200 mg/kg of BW, respectively. After the pre-feeding period, the mice were fasted for 12 h, the mice in the NS group and the E. coli group were gavaged with normal saline, and the mice in the LEO group and DEO group were gavaged with respective dose of EOs for 1 week. One hour after the end of gavage on the 7th day, except that the mice in the normal saline group were intraperitoneally injected with normal saline, the mice in the other groups were intraperitoneally injected with the same concentration of E. coli (108 cfu/ml, 0.15 ml per mouse). The antioxidant indexes were measured including superoxide dismutase (SOD), malondialdehyde (MDA), and myeloperoxidase (MPO) in plasma obtained by taking blood from mouse eyeballs. The inflammatory indexes were measured including interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor alpha (TNF-α) in plasma. The tight junction protein indicators were tested include zona occludens 1 protein (ZO-1), occludin and claudin in mouse duodenum. We found that all of the above indexes for E. coli group were different (P< 0.05) with the NS group. The interaction of EO and dose (E × D) were significant (P < 0.01) for all of the indexes. In addition, LEO at 300 mg/kg BW and DEO at 600 mg/kg BW had better antioxidant and anti-inflammation activity on the infected mice, which reduced (P < 0.05) the plasma concentrations of MDA, MPO, TNF-α, IL-1β, and IL-6, but increased (P < 0.01) the concentrations of SOD. Hematoxylin-eosin (H&E) staining of duodenum observation showed that LEO and DEO reduced inflammatory cell infiltration and maintain the orderly arrangement of epithelial cells. Moreover, supplementation of LEO at 600 mg/kg and DEO at 300 mg/kg BW alleviated (P < 0.05) intestinal barrier injury for increasing the relative expression of ZO-1, occludin and claudin mRNA in mice duodenum. These results showed that the pre-treatment with LEO and DEO had protection of intestinal tissue and inflammation in E. coli infected mice. Both LEO and DEO exhibited activity of antioxidant, anti-inflammatory and alleviating intestinal injury, whereas, compared with DEO, LEO can be active at a lower dosage. Furthermore, as the main active component of LEO, the d-limonene appeared to play not only the major role, but also the joint action with other active components of LEO.

Polygonum cuspidatum Sieb. et Zucc. is a traditional and popular Chinese medicine with a wide spectrum of pharmacological effects such as anti-bacterial, anti-inflammatory, and anti-tumor activities together with other health effects like lowering lipids, preventing diabetes, and regulating the immune system. It is of great significance to explore the complex chemical constituents and metabolic process of Polygonum cuspidatum in vivo to further clarify the effective substances. However, studies on its metabolism in vivo were not comprehensive in previous literature. In this study, ultra-high performance liquid chromatography coupled with Quadrupole-Exactive Orbitrap mass spectrometry was used to comprehensively identify the chemical constituents in Polygonum cuspidatum and further analyze its metabolic profile in rats. Compared with reference substances, various databases, and literature retrieval, 62 compounds were inferred from the Polygonum cuspidatum extract. Furthermore, a total of 119 compounds, including 44 prototype compounds and 75 metabolites, were annotated in rat plasma, urine, and feces. The main metabolic pathways of Polygonum cuspidatum in rats included hydrogenation reduction, hydroxylation, dehydration, methylation, sulfation, and glucuronidation. This is the first systematic study on the chemical constituents of Polygonum cuspidatum and its metabolic profile in vivo, which contributes to finding its bioactive components and seeking its therapeutic targets.

本试验旨在研究饲粮中添加植物精油(EOs)对肉羊甲烷(CH4)产量及瘤胃产甲烷菌区系的影响.试验采用3×3拉丁方设计,选用体重为(64.45±8.56)kg的6只健康杜寒F1代杂交成年瘘管羊,随机分配到3个组[不添加EOs的对照组、添加500 mg/(头·d)桉叶油的桉叶油组和添加500 mg/(头·d)茴香油的茴香油组]中,每组2只,共进行3期试验,每期22 d,其中预试期14 d,正试期8 d.试验期间采用呼吸测热室测定肉羊CH4产量,试验期结束时取瘤胃食糜,采用荧光定量PCR测定肉羊瘤胃微生物数量;采用Illumina MiSeq高通量测序技术测定瘤胃产甲烷菌区系变化.结果显示:与对照组相比,饲粮中添加桉叶油对肉羊CH4产量没有显著影响(P＞0.05),但添加茴香油有使肉羊CH4产量降低的趋势(P=0.08).与对照组相比,饲粮中添加桉叶油或茴香油对肉羊瘤胃中总细菌、总真菌、总原虫和总产甲烷菌数量均无显著影响(P＞0.05);饲粮中添加桉叶油显著降低了瘤胃甲烷短杆菌(Methanobrevibacter ruminantium)和未分类的甲烷短杆菌属(unclassified Methanobrevibacter)的相 对丰度(P＜0.05),极显著增加了Methanobrevibacter euryarchaeote 的相对丰度(P＜0.05);饲粮添加茴香油显著降低了 Methano-brevibacter ruminantium 的相对丰度(P＜0.05),显著提高 了 unclassified Methanobrevibacter 和Methanobrevibacter euryarchaeote的相对丰度(P＜0.05).综上所述,肉羊饲粮中添加500 mg/(头·d)桉叶油或茴香油对肉羊瘤胃微生物数量没有显著影响,但影响了瘤胃产甲烷菌区系,其中茴香油对CH4产量数值上的降低可能是由于其降低了 Methanobrevibacter ruminanti-um 的数量.

PMP-HPLC, FT-IR, and HPSEC fingerprints of 10 batches of polysaccharides from Saposhnikoviae Radix with different production areas and harvest times have been prepared, and the chemometrics analysis was performed. The anti-allergic activity of 10 batches of Saposhnikoviae Radix polysaccharide (SP) was evaluated, and the spectrum-effect relationship of the 10 batches of SP was analyzed by gray correlation degree with the chromatographic fingerprint as the independent variable. The results showed that the PMP-HPLC, HPSEC, and FT-IR fingerprints of 10 batches of SP had a high similarity. Two monosaccharides (rhamnose and galactose), the polysaccharide fragment Mn = 8.67 × 106~9.56 × 106 Da, and the FT-IR absorption peak of 892 cm−1 can be used as the quality control markers of SPs. All 10 batches of SP could significantly inhibit the release of β-HEX in RBL-231 cells, and the polysaccharides harvested from Inner Mongolia in the winter had the best anti-allergic activity. The spectrum-effect relationship model showed that the monosaccharide composition and molecular weight were related to the anti-allergic activity of the SPs. Multiple fingerprints combined with spectrum-effect relationship analysis can evaluate and control the quality of SPs from the aspects of overall quality and efficacy, which has more application value.

Hyperoside is a natural flavonol glycoside, which has antioxidation, antitumor, and anticancer activities together with other healthy effects like improving cardiovascular function, protecting the liver, and regulating the immune system. It is a popular compound used in the traditional Chinese medicine and different studies on hyperoside are present in the literature. However, studies on the metabolism of hyperoside in vivo were not comprehensive. In this study, UPLC-Q-Exactive Orbitrap MS technology was used to establish a rapid and comprehensive analysis strategy to explore the metabolites and metabolic process of hyperoside in rats. The metabolites of hyperoside were systematically identified in rat plasma, urine, and feces. According to the hyperoside standard substance and relevant works of literature, a total of 33 metabolites were identified, including 16 in plasma, 31 in urine, and 14 in feces. Among them, the metabolites quercetin and dihydroquercetin were unambiguously confirmed by comparison with standard substances. In addition, 13 metabolites had not been reported in hyperoside metabolism-related articles at present. The metabolic reactions of hyperoside in vivo were further explored, including phase I metabolism (hydroxylation, dehydroxylation, glycoside hydrolysis, hydrogenation, and hydration) and phase II metabolism (methylation, acetylation, sulfation, and glucuronide conjugation). The fragment ions of hyperoside and its metabolites were usually produced by glucoside bond hydrolysis, the neutral loss of (CO + OH), COH, CO, O, and Retro-Diels Alder (RDA) cleavage. In conclusion, this study comprehensively characterized the metabolism of hyperoside in rats, providing a basis for exploring its various biological activities.

Increasing concerns over the use of antimicrobial growth promoters in animal production has prompted the need to explore the use of natural alternatives such as phytogenic compounds and probiotics. Citrus EOs have the potential to be used as an alternative to antibiotics in animals. The purpose of this research was to study the antibacterial and antioxidant activities of five citrus EOs, grapefruit essential oil (GEO), sweet orange EO (SEO), bergamot EO (BEO), lemon EO (LEO) and their active component d-limonene EO (DLEO). The chemical composition of EOs was analyzed by gas chromatography–mass spectrometry (GC-MS). The antibacterial activities of the EOs on three bacteria (Escherichia coli, Salmonella and Lactobacillus acidophilus) were tested by measuring the minimum inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and inhibition zone diameter (IZD). The antioxidant activities of EOs were evaluated by measuring the free radical scavenging activities of DPPH and ABTS. We found that the active components of the five citrus EOs were mainly terpenes, and the content of d-limonene was the highest. The antibacterial test showed that citrus EOs had selective antibacterial activity, and the LEO had the best selective antibacterial activity. Similarly, the LEO had the best scavenging ability for DPPH radicals, and DLEO had the best scavenging ability for ABTS. Although the main compound of the five citrus EOs was d-limonene, the selective antibacterial and antioxidant activity of them might not be primarily attributed to the d-limonene, but some other compounds’ combined action.

黄芩苷是从黄芩中提取出的一种黄酮类化合物,具有抗菌、抗炎和抗氧化应激等生物功能.黄芩苷作为一种饲料添加剂可提高奶牛的泌乳性能和抗病能力,具有广泛的应用前景和潜在价值.本文就黄芩苷的理化性质、代谢途径、生物学功能以及在奶牛生产上的应用研究进行综述,为黄芩苷在奶牛生产中的实践应用提供理论依据.

植物精油(EOs)是经蒸馏等方式从植物组织中提取的易挥发油状芳香物质,具有良好的抗菌、抗氧化和抗炎活性.EOs能够提高动物机体的免疫性能并促进动物生长,被认为具有良好的替抗潜力,近年来在反刍动物上的应用逐渐广泛.本文综述了EOs对反刍动物瘤胃发酵、甲烷产量、动物生产性能、畜产品品质及机体免疫性能的影响及其作用机制,旨在为EOs在反刍动物生产中的推广应用提供理论参考.