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Impact of Phosphate Solubilizing Bacterial Agent on Cadmium Bioavailability and Microbial Communities in Soil and Cd Accumulation in Lettuce Plants
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作者 Yue Yu Ping Li +3 位作者 Yanhong Wang Xinzhe Lu Chunlei Huang Hanqin Yin 《Journal of Earth Science》 2025年第5期2266-2278,共13页
Cadmium(Cd)contamination in soil can lead to food chain accumulation and greatly impacts on human health.Bioremediation has gained more and more attention due to its environment-friendly,high efficiency and low-cost.I... Cadmium(Cd)contamination in soil can lead to food chain accumulation and greatly impacts on human health.Bioremediation has gained more and more attention due to its environment-friendly,high efficiency and low-cost.In this work,we studied the impact of phosphate solubilizing bacterial agent(PSBA)on Cd bioavailability,microbial communities in soil and Cd accumulation in lettuce plants with pot experiment and field trial.Results of pot experiment showed that PSBA could decrease the bioavailability of Cd(Cd-acid extractable from 3.30 to 2.34mg/kg,Cd-reducible from 1.94 to 1.56 mg/kg),promote lettuce plants growth(increased by 33.85%height and by 33.65%fresh weight)and reduce the accumulation of Cd(from 5.85 to 3.73 mg/kg)in lettuce plants.High-throughput sequencing identified that PSBA could change the composition and structure of the soil microbial communities.The relative abundances of the three ecologically beneficial bacterial families of Pseudomonadaceae,Burkholderiaceae,and Enterobacteriaceae increased from 2.29%to 5.13%,0.56%to 5.24%,and 1.87%to 16.93%,respectively.And the former two were positively correlated with redox potential(Eh)(R^(2)=0.474,p<0.05,R^(2)=0.590,p<0.01,respectively).The bacterial networks were more complex in PSBA treatment,reflecting through more links(from 1893 to 2185)and a higher average degree(from 38.242 to 45.052)and density(from 0.390 to 0.469).Results of field trial demonstrated that PSBA could also decrease Cd content in lettuce plants and microbial composition in soil.This study indicated that PSBA could be served as an alternative material in bioremediation of Cd contamination in soil. 展开更多
关键词 Cd bioavailability microbial communities physicochemical properties PSBA BIOREMEDIATION environmental geology
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Enhancing bioavailability in traditional Chinese medicine: Exploring strategies for optimized therapeutic efficacy
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作者 John Osilama Thomas Ifeoluwa Margaret Idowu Sunitha Ganesha Rudrapatna 《Natural Therapy Advances》 2025年第1期55-69,共15页
Traditional Chinese medicine(TCM)offers diverse therapeutic compounds but faces challenges like poor bioavailability and instability.Recent innovations in drug delivery systems,including nanotechnology-based drug deli... Traditional Chinese medicine(TCM)offers diverse therapeutic compounds but faces challenges like poor bioavailability and instability.Recent innovations in drug delivery systems,including nanotechnology-based drug delivery systems have shown potential to enhance solubility,stability,and therapeutic efficacy.This review examines these advancements,focusing on their mechanisms and applications in improving TCM formulations.Cutting-edge techniques,such as microneedles,iontophoretic patches,and self-orienting applicators,are also discussed for their potential to revolutionize TCM delivery.By bridging traditional wisdom with modern innovations,this review emphasizes the transformative role of these strategies in advancing TCM's integration into contemporary medicine. 展开更多
关键词 traditional Chinese medicine bioavailability enhancers drug delivery NANOCARRIERS therapeutic efficacy
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Deep learning-based simultaneous bioavailability assessment and speciation analysis of dissolved organic copper
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作者 Zhaojing Huang Hao Li +4 位作者 Jiayi Luo Shunxing Li Ming Zhao Fengjiao Liu Haijiao Xie 《Chinese Chemical Letters》 2025年第5期645-650,共6页
Algal copper uptake(i.e.,Cu bioavailability)in the euphotic zone plays a vital role in algal photosynthesis and respiration,affecting the primary productivity and the source and sink of atmospheric carbon.Algal Cu upt... Algal copper uptake(i.e.,Cu bioavailability)in the euphotic zone plays a vital role in algal photosynthesis and respiration,affecting the primary productivity and the source and sink of atmospheric carbon.Algal Cu uptake is controlled by natural dissolved organic Cu(DOCu)speciation(i.e.,complexed with the dissolved organic matter)that conventionally could be tested by model prediction or molecular-level characterizations in the lab,while DOCu uptake are hardly directly assessed.Thus,the new chemistrybiology insight into the mechanisms of the Cu uptake process in algae is urgent.The DOCu speciation transformation(organic DOCu to free Cu(II)ions),enzymatic reduction-induced valence change(reduction of free Cu(II)to Cu(I)ions),and algal Cu uptake at the algae-water interface are imitated.Herein,an intelligent system with DOCu colorimetric sensor is developed for real-time monitoring of newly generated Cu(I)ions.Deep learning with whole sample image-based characterization and powerful feature extraction capabilities facilitates colorimetric measurement.In this context,the Cu bioavailability with 7 kinds of organic ligands(e.g.,amino acids,organic acids,carbohydrates)can be predicted by the mimetic intelligent biosensor within 15.0min,i.e.,the DOCu uptake and speciation is successfully predicted and streamlined by the biomimetic approach. 展开更多
关键词 Metal bioavailability Metal speciation Primary productivity Intelligent analysis Biomimetic sensor
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Propolis as a promising functional ingredient:a comprehensive review on extraction,bioactive properties,bioavailability,and industrial applications
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作者 Mengyao Liu Xiangxin Li +5 位作者 Hualei Chen Fei Pan Xing Zheng Maurizio Battino Wenli Tian Wenjun Peng 《Food Science and Human Wellness》 2025年第10期3775-3795,共21页
Propolis is a resinous complex mixture made from plant resins collected by worker bees and mixed with their own secretions.It is rich in polyphenols and flavonoids and thus has a wide range of biological activities an... Propolis is a resinous complex mixture made from plant resins collected by worker bees and mixed with their own secretions.It is rich in polyphenols and flavonoids and thus has a wide range of biological activities and is considered a functional source for promoting human health.However,propolis and its bioactive compounds have poor water solubility,rapid and intense metabolism,and low oral bioavailability,which limits their wide application.In this paper,the main bioactive substances in propolis were summarized,and the biological characteristics and therapeutic potential of propolis and its bioactive substances were discussed.In addition,this paper discussed the factors affecting the bioavailability of propolis and its functional ingredients,focusing on the research progress in improving the bioavailability and bioactivity of propolis and its functional ingredients using nanoencapsulation technology.Finally,the current situation of the global propolis market and the applications of propolis products in the pharmaceutical,food,cosmetic and other industrial fields were discussed,providing useful references for promoting the development of the propolis industry. 展开更多
关键词 PROPOLIS Chemical composition Biological activities bioavailability Industrial application
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Effect of Hydrothermal Coupling on Phosphorus Bioavailability in Vegetable Soil
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作者 Wenyan HE Xicheng WANG +3 位作者 Mengdie LI Aomingyang LI Tianya LIU Jifu LI 《Meteorological and Environmental Research》 2025年第1期59-63,共5页
In this paper,the vegetable field in the teaching base of College of Agriculture,Yangtze University was taken as the research object.The indoor simulation method was used to explore the effects of temperature and mois... In this paper,the vegetable field in the teaching base of College of Agriculture,Yangtze University was taken as the research object.The indoor simulation method was used to explore the effects of temperature and moisture on the phosphorus(P)bioavailability of vegetable soil.Three temperature gradients[T1(15℃),T2(25℃),T3(35℃)]and three humidity gradients[W1(40%),W2(70%),W3(100%)]were set in the test.The results showed that it could improve the contents of HCl-P,Enzyme-P,Citrate-P,and Olsen-P in vegetable soil by increasing soil moisture content;temperature rise was helpful to increase the contents of HCl-P and Olsen-P,but it could reduce the content of Citrate-P.The contents of Enzyme-P and CaCl 2-P were significantly affected by hydrothermal interaction.Within a certain range of soil temperature and humidity,temperature and moisture had a positive coupling effect on soil P bioavailability components,and significantly affected soil P supply capacity. 展开更多
关键词 Vegetable field Hydrothermal coupling Soil phosphorus Phosphorus bioavailability INTERACTION
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Innovative 3D microfluidic intestinal organoid model for assessing cadmium bioavailability in food:implications for enhanced exposure risk assessment
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作者 Yan Li Wen Sun +6 位作者 Qiao Wang Wan Shi Yu Chen Zhiyong Gong Xiao Guo Xin Liu Yongning Wu 《Food Science and Human Wellness》 2025年第5期1687-1696,共10页
Given the severe toxicity and widespread presence of cadmium(Cd)in staple foods such as rice,accurate dietary exposure assessments are imperative for public health.In vitro bioavailability is commonly used to adjust d... Given the severe toxicity and widespread presence of cadmium(Cd)in staple foods such as rice,accurate dietary exposure assessments are imperative for public health.In vitro bioavailability is commonly used to adjust dietary exposure levels of risk factors;however,traditional planar Transwell models have limitations,such as cell dedifferentiation and lack of key intestinal components,necessitating a more physiologically relevant in vitro platform.This study introduces an innovative three-dimensional(3D)intestinal organoid model using a microfluidic chip to evaluate Cd bioavailability in food.Caco-2 cells were cultured on the chip to mimic small intestinal villi's 3D structure,mucus production,and absorption functions.The model's physiological relevance was thoroughly characterized,demonstrating the formation of a confluent epithelial monolayer with well-developed tight junctions(ZO-1),high microvilli density(F-actin),and significant mucus secretion(Alcian blue staining),closely resembling the physiological intestinal epithelium.Fluorescent particle tracking confirmed its ability to simulate intestinal transport and diffusion.The Cd bioavailability in rice measured by the 3D intestinal organoid model((9.07±0.21)%)was comparable to the mouse model((12.82±3.42)%)but significantly lower than the Caco-2 monolayer model((26.97±1.11)%).This 3D intestinal organoid model provides a novel and reliable strategy for in vitro assessment of heavy metal bioavailability in food,with important implications for food safety and risk assessment. 展开更多
关键词 Planar Transwell model 3D intestinal organoid model Physiological relevance Cd bioavailability
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Electrostatic spraying for fine-tuning particle dimensions to enhance oral bioavailability of poorly water-soluble drugs
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作者 Jung Suk Kim Seunghyun Cheon +10 位作者 Mi Ran Woo Sanghyun Woo Jee-Eun Chung Yu Seok Youn Kyung Taek Oh Soo-Jeong Lim Sae Kwang Ku Bao Loc Nguyen Jong Oh Kim Sung Giu Jin Han-Gon Choi 《Asian Journal of Pharmaceutical Sciences》 SCIE CAS 2024年第5期139-151,共13页
While spray-drying has been widely utilized to improve the bioavailability of poorly water-soluble drugs,the outcomes often exhibit suboptimal particle size distribution and large particle sizes,limiting their effecti... While spray-drying has been widely utilized to improve the bioavailability of poorly water-soluble drugs,the outcomes often exhibit suboptimal particle size distribution and large particle sizes,limiting their effectiveness.In this study,we introduce electrostatic spraying as an advanced technology tailored for poorly water-soluble drugs,enabling the fabrication of nanoparticles with fine and uniform particle size distribution.Regorafenib(1 g),as a model drug,copovidone(5 g),and sodium dodecyl sulfate(0.1 g)were dissolved in 200 ml ethanol and subjected to conventional-spray-dryer and electrostatic spray dryer.The electrostatic spray-dried nanoparticles(ESDN)showed smaller particle sizes with better uniformity compared to conventional spray-dried nanoparticles(CSDN).ESDN demonstrated significantly enhanced solubility and rapid release in water.In vitro studies revealed that ESDN induced apoptosis in HCT-116 cells to a greater extent,exhibiting superior cytotoxicity compared to CSDN.Furthermore,ESDN substantially improved oral bioavailability and antitumor efficacy compared to CSDN.These findings suggest that ESD shows potential in developing enhanced drug delivery systems for poorly water-soluble drugs,effectively addressing the limitations associated with CSD methods. 展开更多
关键词 Electrostatic spray drying Poorly water-soluble drug Regorafenib Particle size distribution Oral bioavailability Oral antitumor efficacy
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Boswellic acids: a review on its pharmacological properties, molecular mechanism and bioavailability
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作者 Na Cui Ming-Jie Li +3 位作者 Yi-Wen Wang Qian Meng Ya-Jun Shi Yi Ding 《Traditional Medicine Research》 2024年第10期64-74,共11页
Boswellic acids is a general term for a series of pentacyclic triterpenoid compounds that are isolated from the oleogin resin of the Boswellia genus and serve as the main active ingredient.It exhibits a wide range of ... Boswellic acids is a general term for a series of pentacyclic triterpenoid compounds that are isolated from the oleogin resin of the Boswellia genus and serve as the main active ingredient.It exhibits a wide range of biological activities,such as anti-inflammatory,anti-cancer,antibacterial,antiviral,hepatoprotective,neuroprotective,anti-diabetic,and anti-thrombotic properties.As a result,it has gained significant recognition among practitioners of traditional Chinese and Indian medicine.These biological effects may be associated with multiple molecular targets and signal transduction pathways.However,the poor pharmacokinetic properties of the substance lead to lower bioavailability,which affects its effectiveness.To address this issue,scientists have proposed a number of strategies,such as solid dispersions,phytosome®technologies,and novel drug delivery systems.This article aims to provide a comprehensive overview for boswellic acids on the phytochemistry,molecular mechanisms,potential therapeutic applications,and strategies to improve bioavailability. 展开更多
关键词 boswellic acids molecular mechanism pharmacological properties bioavailability
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Enhancement in Bioavailability of CurCousin®, A Minor Metabolite from Curcuma longa by Addition of BioPerine® —A Pharmacokinetic Study
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作者 Muhammed Majeed Kalyanam Nagabhushanam +2 位作者 Sarang Bani Anjali Pandey Smitha Thazhathidath 《Journal of Biosciences and Medicines》 2024年第2期282-293,共12页
In recent years, metabolic syndrome has been a growing health concern across the world. The role of nutraceuticals and functional foods in this area has a significant place due to the adverse effects of contemporary m... In recent years, metabolic syndrome has been a growing health concern across the world. The role of nutraceuticals and functional foods in this area has a significant place due to the adverse effects of contemporary modes of treatment. CurCousin<sup>®</sup> is a nutritional ingredient containing bioactive Calebin A, (analog of Curcumin) with self-affirmed GRAS status. CurCousin<sup>®</sup> has been a clinically studied dietary supplement ingredient with a positive impact on body weight, lipid levels and metabolic health. Bioenhancers play an important role in increasing the bioavailability of the active in turn enhancing efficacy as well as reducing the dosage required to achieve the therapeutic effect. This study investigated the possible pharmacokinetic interaction between CurCousin<sup>®</sup> at two different doses (2.25 and 4.5 mg/kg) in the presence and absence of BioPerine<sup>®</sup> (0.27 mg/kg), a natural bioenhancer in Sprague-Dawley rats. The results revealed that the addition of BioPerine<sup>®</sup> into CurCousin<sup>®</sup> (2.25 mg/kg) half the dose when administered enhances the bioavailability and was equipotent to CurCousin<sup>®</sup> (4.5 mg/kg) double the dose without BioPerine<sup>®</sup>. Thus, leading to future clinical studies to evaluate its improved pharmacological efficacy as well as reduced therapeutic dosage. 展开更多
关键词 Metabolic Health bioavailability PHARMACOKINETICS CurCousin® BioPerine® Calebin A
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Preparation and bioavailability in healthy volunteers of cefaclor modified-release capsules 被引量:1
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作者 胡连栋 王成伟 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第1期57-60,共4页
Aim To investigate whether modified-release cefaclor capsules could lead to a more suitable pharmacokinetic profile in the plasma. Methods Cefaclor pellets were prepared by extrusion/spheronization and coated by Eudra... Aim To investigate whether modified-release cefaclor capsules could lead to a more suitable pharmacokinetic profile in the plasma. Methods Cefaclor pellets were prepared by extrusion/spheronization and coated by Eudragit L30D-55 or Eudragit NE30D, then the two sorts of pellets were filled to capsules in a 35:65 ratio to made a modified-release (MR) capsules. The bioavailability of the MR capsules was studied in 24 healthy volunteers after oral administration in a fast state using a commercially available immediate release (IR) capsule as a reference. Results The results showed that the MR formulation had a relatively good bioavailability compared with the commercial capsules, as well as a longer time keeping drug level above MIC than immediate release capsule. The relative bioavailability of the MR capsules was 97.4- 12.1%. Conclusion The data of the present study indicate that time of cefaclor plasma concentration above MIC can be substantially prolonged if cefaclor is administered as a modified- release product. 展开更多
关键词 CEFACLOR Modified- release PELLETS CAPSULES bioavailability.
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负载二氢杨梅素的玉米醇溶蛋白-阿拉伯胶纳米粒子的制备及分析 被引量:1
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作者 常大伟 曹佳怡 +4 位作者 任娜 王虎玄 孙玉姣 沈文 SARA Sendi 《食品工业科技》 北大核心 2025年第12期30-40,共11页
本研究将二氢杨梅素(Dihydromyricetin,DMY)作为核心来构建纳米粒子,并借助纳米粒子对DMY予以包封,旨在解决其水溶性差以及稳定性欠佳的难题,从而提高其利用率与生物活性。采用反溶剂沉淀法,以DMY为芯材,以玉米醇溶蛋白(Zein)为载体,构... 本研究将二氢杨梅素(Dihydromyricetin,DMY)作为核心来构建纳米粒子,并借助纳米粒子对DMY予以包封,旨在解决其水溶性差以及稳定性欠佳的难题,从而提高其利用率与生物活性。采用反溶剂沉淀法,以DMY为芯材,以玉米醇溶蛋白(Zein)为载体,构建Zein-阿拉伯胶(GA)纳米营养递送体系,以粒径、多分散指数(PDI)、zeta电位、包封率为指标优化了Zein/GA-DMY纳米粒子的制备条件。同时,采用傅里叶红外光谱(FT-IR)和X射线衍射(XRD)探讨了Zein、GA和DMY之间的相互作用,利用扫描电子显微镜(SEM)观察了该体系的微观形貌。结果表明,当Zein与阿拉伯胶的质量比为1:2,Zein与DMY质量比为10:1时,制备的纳米粒子粒径较小(191.04 nm),PDI为0.164,zeta电位为-17.70 mV,包封率为76.17%。氢键、静电和疏水相互作用是使该纳米粒子形成的主要驱动力,DMY以非晶体状态成功包埋在Zein/GA-DMY纳米粒子中,复合物呈球形,且分布均匀。GA的包覆使纳米粒子在一定条件下具备pH、加热、盐离子及储藏稳定性,扩展了其应用范围;体外抗氧化和模拟胃肠道消化实验表明经复合纳米粒子包封后DMY仍具备较强的抗氧化活性,同时呈现缓释特性。因此,本研究可为DMY在功能性食品领域的应用提供一定的理论基础。 展开更多
关键词 二氢杨梅素 玉米醇溶蛋白 阿拉伯胶 纳米粒子 稳定性 生物利用度 壳-核结构
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虾青素生物利用度的影响因素及其改善方法研究进展
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作者 陈芳甜 谷彩霞 +2 位作者 周庆新 张勇 高慧 《肉类研究》 北大核心 2025年第7期73-80,共8页
虾青素因卓越的抗氧化和穿透血脑屏障特性,备受食品、保健品和医药等行业关注。然而,天然存在的虾青素受水不溶、易降解失活等因素影响,导致其生物利用度较低,应用受到严重限制。因此,研究改善虾青素生物利用度的策略意义重大。虾青素... 虾青素因卓越的抗氧化和穿透血脑屏障特性,备受食品、保健品和医药等行业关注。然而,天然存在的虾青素受水不溶、易降解失活等因素影响,导致其生物利用度较低,应用受到严重限制。因此,研究改善虾青素生物利用度的策略意义重大。虾青素的分子结构、食品基质效应及宿主状况等对虾青素的生物利用度具有重要影响。研究表明,通过优化食品加工过程、设计科学的运载体系和构建共消化体系等方法可以显著改善虾青素的生物利用度。本文从虾青素的吸收机制、生物利用度的影响因素及其改善方法等方面进行综述,并对虾青素生物利用度的研究趋势和前景进行展望。以期为探究虾青素营养功能及其终端产品开发提供参考。 展开更多
关键词 虾青素 生物利用度 分子结构 运载体系
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复合酶法辅助提取的桑葚多糖结构表征及生物有效性
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作者 李学玲 李梦绮 +2 位作者 李素丽 郭洁 任四妹 《中国酿造》 北大核心 2025年第7期119-125,共7页
为优化复合酶解法桑葚多糖提取工艺条件,采用复合酶(纤维素酶、果胶酶、碱性蛋白酶和木瓜蛋白酶)法提取桑葚多糖,运用单因素和正交试验优化其提取工艺条件;采用红外光谱、扫描电子显微镜(SEM)等对桑葚多糖进行结构表征,建立体外消化模... 为优化复合酶解法桑葚多糖提取工艺条件,采用复合酶(纤维素酶、果胶酶、碱性蛋白酶和木瓜蛋白酶)法提取桑葚多糖,运用单因素和正交试验优化其提取工艺条件;采用红外光谱、扫描电子显微镜(SEM)等对桑葚多糖进行结构表征,建立体外消化模型模拟桑葚多糖的体外消化过程探究其生物有效性。结果表明,桑葚多糖的最佳复合酶提取工艺条件为:纤维素酶、果胶酶、碱性蛋白酶、木瓜蛋白酶添加量分别为2.0%、2.0%、1.4%、0.2%;料液比1∶80(g∶mL),酶解pH值5,酶解时间20 min,酶解温度50℃。在此最佳工艺条件下,桑葚多糖得率达65.64%。结构表征表明,桑葚多糖分子质量为250139 kDa,主要由葡萄糖(26.25%)和半乳糖(25.20%)构成。桑葚多糖不具备晶体结构,形态结构为层状和孔隙结构。生物有效性分析结果表明,复合酶解法制备桑葚多糖生物利用度(37.69%)优于单一酶提取法(25.32%)和热水浸提法(17.53%)。 展开更多
关键词 桑葚多糖 复合酶法 提取工艺 结构表征 生物有效性
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有机络合矿物质在动物营养中的应用:配体来源、生产工艺、吸收机制与应用效果
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作者 邓泽元 李男 郑溜丰 《饲料工业》 北大核心 2025年第20期1-10,共10页
矿物质作为动物体必需的营养素,参与多种关键生理过程,但传统无机矿物质饲料添加剂存在吸收效率低、生物利用率差等问题,且易引发环境污染与动物健康风险。有机络合矿物质通过金属离子与有机配体(如有机酸、氨基酸、小肽、多糖等)的配... 矿物质作为动物体必需的营养素,参与多种关键生理过程,但传统无机矿物质饲料添加剂存在吸收效率低、生物利用率差等问题,且易引发环境污染与动物健康风险。有机络合矿物质通过金属离子与有机配体(如有机酸、氨基酸、小肽、多糖等)的配位作用形成稳定复合物,展现出更高的生物利用率与环境效益。文章系统归纳了有机络合矿物质中有机配体的来源、生产工艺关键因素、吸收机制及其在畜禽生产中的应用效果。详细阐述了不同配体类型(有机酸、氨基酸、小肽、多糖)的特性及其对矿物质吸收的影响,结合具体研究案例分析了各类有机络合矿物质在提升动物生产性能、改善肠道健康与增强抗应激能力等方面的应用潜力。尽管有机络合矿物质具有显著优势,但其在体内吸收机制研究的深度与广度仍不足。文章旨在为有机络合矿物质在功能性饲料与新型矿物质补充剂开发中的应用提供全面参考,推动动物营养领域的可持续发展。 展开更多
关键词 有机络合矿物质 生物利用率 生产工艺 吸收机制 畜禽生产
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安徽省石台县土壤硒、镉赋存状态及其意义
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作者 侯克斌 徐利强 +1 位作者 刘超 伍佳杰 《资源环境与工程》 2025年第4期409-416,共8页
石台县是安徽省富硒产业发展较为突出的地区,近年来随着富硒土壤的持续开发,土壤Se含量与农产品富硒率呈现下降趋势,这一问题日益凸显。同时,石台县属于地质高背景地区,土壤中Se与Cd的伴生问题长期制约着土壤资源的生态安全。以与农业... 石台县是安徽省富硒产业发展较为突出的地区,近年来随着富硒土壤的持续开发,土壤Se含量与农产品富硒率呈现下降趋势,这一问题日益凸显。同时,石台县属于地质高背景地区,土壤中Se与Cd的伴生问题长期制约着土壤资源的生态安全。以与农业发展关系密切的耕地、园地土壤为研究对象,系统采集表层土壤样,开展土壤环境质量评价以及Se和Cd的赋存状态、影响因素与生态效应研究。结果表明,石台县耕地、园地土壤环境质量影响因素主要为Cd;表层(0~20 cm)土壤以及0~40 cm土壤细组分中总硒(TSe)含量均远高于总镉(TCd)含量,但有效硒(ASe)含量(0.005~0.099 mg/kg)远低于有效镉(ACd)含量(0.032~0.885 mg/kg),农产品相对更易富集Cd;土壤Se主要以腐殖酸态、有机结合态和残渣态赋存,而Cd主要以离子交换态、铁锰氧化物结合态和残渣态赋存,生物可利用度远高于Se;土壤pH、有机质、阳离子交换量、水分含量等单一因素对土壤Se并无明显影响,但对土壤Cd及农作物吸收作用明显。全面系统的土壤Se、Cd的赋存状态研究为富硒土壤可持续开发、富硒特色农业产业发展与农业生产环境安全保障提供了依据。 展开更多
关键词 土壤 SE CD 元素赋存状态 生物可利用度
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蚓粪对茶树吸收积累Cu、Pb的影响及其作用机制
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作者 周波 崔莹莹 +5 位作者 张晓龙 陈义勇 张曼 黎健龙 刘科学 唐劲驰 《茶叶通讯》 2025年第3期314-320,共7页
为探究蚓粪对土壤重金属Cu、Pb化学形态及茶树对土壤中Cu、Pb吸收转运的影响,在有茶树种植的Cu、Pb污染土壤系统中施入蚓粪,并以牛粪和化肥为对照,系统研究在蚓粪和茶树根系共同作用下土壤中Cu、Pb的化学形态变化以及茶树对Cu、Pb的吸... 为探究蚓粪对土壤重金属Cu、Pb化学形态及茶树对土壤中Cu、Pb吸收转运的影响,在有茶树种植的Cu、Pb污染土壤系统中施入蚓粪,并以牛粪和化肥为对照,系统研究在蚓粪和茶树根系共同作用下土壤中Cu、Pb的化学形态变化以及茶树对Cu、Pb的吸收转运情况。结果表明,在土壤中施用蚓粪可显著降低交换性氢和交换性铝的含量,增加水提和盐提pH值,有效缓解土壤酸化程度,并可显著增加有机碳、全氮以及氮、磷、钾等速效养分。在有茶树根系作用的土壤系统中,蚓粪处理组Cu、Pb的水溶-交换态含量较对照处理组分别降低66.88%和57.79%,蚓粪降低土壤水溶-交换态Cu、Pb含量的作用效果优于牛粪和化肥处理组。蚓粪处理组茶树根部和叶部Cu的含量比CK组分别下降36.61%和23.08%。可见,在种植茶树的土壤中施用蚓粪可显著降低土壤酸化程度,增加有机碳含量,这有利于降低土壤中Cu、Pb的生物有效性。本研究结果对有Cu、Pb重金属轻微污染风险的茶园土壤治理具有一定借鉴意义。 展开更多
关键词 茶园 施肥 蚓粪 重金属形态 生物有效性 茶树 吸收积累
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土壤有机磷的矿化及其调控研究进展 被引量:6
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作者 张万年 杨子 +5 位作者 严玉鹏 王小明 殷辉 徐仁扣 谭文峰 冯雄汉 《土壤学报》 北大核心 2025年第2期334-347,共14页
有机磷作为土壤磷库的重要组成部分,其矿化过程在全球磷循环中发挥着重要作用,深入理解土壤有机磷矿化过程有助于陆地生态系统中磷的高效利用与管理。土壤有机磷矿化机制主要关注由能量需求驱动的微生物对有机质氧化的生物矿化,以及植... 有机磷作为土壤磷库的重要组成部分,其矿化过程在全球磷循环中发挥着重要作用,深入理解土壤有机磷矿化过程有助于陆地生态系统中磷的高效利用与管理。土壤有机磷矿化机制主要关注由能量需求驱动的微生物对有机质氧化的生物矿化,以及植物对磷养分需求驱动的磷酸酶介导有机磷水解的生化矿化。近年来,非生物矿化尤其是矿物表面催化水解矿化机制及其作用也越来越受到重视。土壤生态系统中的碳和氮等生源要素与土壤有机磷矿化密切相关,其中碳通过有效驱动微生物对有机磷进行矿化,而氮则通过酶代谢的方式实现,二者相互作用,深刻影响土壤有机磷矿化过程。此外,不同农艺措施(如施肥方式、耕作方式、施用生物炭等)、土壤理化性质(如pH、温度、土壤含水量、土壤通气状况等)、微生物生物量、土壤CO_(2)浓度、植被、污染物等诸多因素均会影响土壤有机磷矿化并产生相应的环境生态效应。本文综述了土壤有机磷矿化研究进展,归纳了有机磷矿化的土壤过程、影响因素和调控途径,并提出了当前存在的问题与未来展望。 展开更多
关键词 土壤有机磷 磷循环 磷酸酶 矿化过程 磷生物有效性
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负载五味子乙素的玉米醇溶蛋白/葡聚糖纳米粒处方优化、表征及口服药动学研究
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作者 王肖雲 李泽运 +1 位作者 王贇 赖耀文 《中草药》 北大核心 2025年第16期5749-5762,共14页
目的制备负载五味子乙素的玉米醇溶蛋白/葡聚糖纳米粒(schisandrin B-loaded by zein-dextran nanoparticles,Sch B-zein/Dex-NPs),考察其体外释药行为及体内药动学行为。方法采用反溶剂沉淀法制备Sch B-zein/Dex-NPs。单因素考察Sch B-... 目的制备负载五味子乙素的玉米醇溶蛋白/葡聚糖纳米粒(schisandrin B-loaded by zein-dextran nanoparticles,Sch B-zein/Dex-NPs),考察其体外释药行为及体内药动学行为。方法采用反溶剂沉淀法制备Sch B-zein/Dex-NPs。单因素考察Sch B-zein/Dex-NPs影响因素,使用Box-Behnken设计-效应面法(Box-Behnken design-response surface method,BBD-RSM)优化Sch B-zein/Dex-NPs处方。透射电子显微镜(transmission electron microscopy,TEM)观察Sch B-zein/Dex-NPs形貌,傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)研究其结合机制,X射线粉末衍射(X-ray powder diffraction,XRPD)法分析五味子乙素晶型。测定Sch B-zein/Dex-NPs在纯化水、模拟胃液和模拟肠液中的饱和溶解度,透析袋法考察在模拟胃肠液中体外释药行为。SD大鼠分别ig给予五味子乙素和Sch B-zein/Dex-NPs粉末,计算其主要药动学参数。结果Sch B-zein/Dex-NPs最佳处方为玉米醇溶蛋白质量浓度为19.5 g/L,反溶剂相与溶剂相体积比2.95∶1,葡聚糖质量浓度为5.0 g/L。包封率、载药量、粒径及ζ电位分别为(89.34±0.71)%、(4.91±0.05)%和(179.79±5.52)nm和(-32.16±0.69)m V,外貌为类球形。五味子乙素可能与玉米醇溶蛋白之间发生了氢键络合作用,五味子乙素以无定形态存在于Sch B-zein/Dex-NPs粉末中。Sch B-zein/Dex-NPs将五味子乙素在纯化水、模拟胃液和模拟肠液中溶解度分别增加至61.99、65.13和64.38倍。Sch B-zein/Dex-NPs在模拟胃、肠液中12 h累积释放率分别提高至71.68%和87.87%,释药行为均符合Weibull模型。药动学结果显示,Sch B-zein/Dex-NPs的达峰时间(t_(max))延后至(2.08±0.46)h,半衰期(t_(1/2))延长至(4.42±1.78)h,达峰浓度(C_(max))和相对口服吸收生物利用度分别提高至3.82倍和4.36倍。结论Sch B-zein/Dex-NPs包封率大于80%,显著增加了五味子乙素的溶解度、释放度及生物利用度,为后续研究奠定实验基础。 展开更多
关键词 五味子乙素 玉米醇溶蛋白 葡聚糖 Box-Behnken设计-效应面法 纳米粒 溶解度 释放度 生物利用度
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Bioavailability of 10-hydroxycamptothecin-phospholipid complex loaded by solid dispersion and lipid-based formulations 被引量:3
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作者 吴先闯 郝海军 +3 位作者 刘瑜新 宋晓勇 张永州 张红芹 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2015年第12期780-788,共9页
Previous study has shown that 10-hydroxycamptothecin(HCPT) has well-established pharmacological effects in vitro.However,its in vivo bioavailability is very poor due to various problems,which severely restricts its ... Previous study has shown that 10-hydroxycamptothecin(HCPT) has well-established pharmacological effects in vitro.However,its in vivo bioavailability is very poor due to various problems,which severely restricts its clinical applications.In the present study,phospholipid complex(PC) technology was employed to improve the solubility and bioavailability of HCPT.XRD data confirmed the formation of HCPT-PC.However,our previously prepared HCPT-PC is too sticky,which may result in the slow dissolution rate and negative effects on its absorption.Therefore,we prepared HCPT-PC-solid dispersion(HCPT-PC-SD)and lipid-based formulations of HCPT-PC through simple preparation process.The results showed that the dissolution rate of HCPT-PC was effectively improved by solid dispersion technology,which reached 91.73%in 45 min.Pharmacokinetic study revealed that the AUC_(0-t) of HCPT-PC-SD and HCPT-PC lipid-based formulations was effectively further increased compared with HCPT-PC.Moreover,we found that the combination of SD technology and lipid-base formulations could be a promising drug-delivery system to improve the oral bioavailability of HCPT-PC.In addition,we showed that the bioavailability of HCPT-PC lipid-base formulations was even greater than that of HCPT-PC-SD.In particular,lipid-base formulations could be prepared just by a simple method,suggesting its feasibility of industrialization. 展开更多
关键词 10-HYDROXYCAMPTOTHECIN Phospholipid complex Solid dispersion Lipid-based formulations bioavailability
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Determination of Loratadine in Human Plasma by High Performance Liquid Chromatography-Electrospray Mass Spectrometry and Studies on Its Pharmacokinetics and Relative Bioavailability 被引量:3
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作者 陈钧 高科攀 +5 位作者 史振祺 陆伟 蒋新国 荣征星 黄霞 陈红专 《Journal of Chinese Pharmaceutical Sciences》 CAS 2002年第4期137-141,共5页
A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined ... A new HPLC MS method to determine loratadine in human plasma was established. The method involved extracting drug with organic solvent under basic conditions. The samples were seperated by ODS column and determined by mass detector. The calibration curve of loratadine was linear within the range of 0.4~100 ng·mL -1 with r=0.9995 . The recovery of this method was within 95%~104%, within day and between day RSD were less than 12%. To study the pharmacokinetics and relative bioavailability of loratadine tablets, two formulations of loratadine tablets were given to 18 healthy male volunteers according to a randomized 2 way cross over design. The C max , AUC 0 t and T max values of the two formulations were 51.89±20.18 ng·mL -1 and 52.48±22.35 ng·mL -1 ; 140.75±88.42 ng·h·mL -1 and 147.24±92.33 ng·h·mL -1 ; 0.81±0.35 h and 0.81±0.27 h respectively. Results from statistic analysis showed that there were no significant difference between the C max , AUC 0-t and T max values of the two formulations. The relative bioavailability of tablets I with respect to tablets II was 97%±13% from the AUC 0 t measurement. Bioequivalance was observed between the two tablets. 展开更多
关键词 LORATADINE HPLC MS PHARMACOKINETICS bioavailability
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