Research Progress of Deep Eutectic Solvents in Extraction of Plant Flavonoids

As a new type of green solvents,deep eutectic solvents(DESs)have the advantages of strong extraction ability,designability,simple preparation,low price,recoverability and biodegradation,and show great application potential in the field of plant flavonoid extraction.In this paper,the definition,classification and preparation methods of DESs were introduced.The effects of DES composition,molar ratio of DES components,water content of DES systems,liquid-material ratio,extraction temperature,extraction time and extraction auxiliary techniques on the extraction yield of plant flavonoids were expounded.The recycling methods of DESs were summarized.Existing problems of DESs in the field of plant flavonoids extraction were pointed out,and further research direction and trend were analyzed and prospected.

Role of flavonoids in plant interactions with the environment and against human pathogens-A review

Flavonoids are widely-distributed polyphenolic secondary metabolites with diverse biological activities in plants and benefit human health as protective dietary agents.They participate in plants' responses to harsh environmental conditions and effectively regulate the cell differentiation and growth.In plants,the majority of their functions are attributed to their strong antioxidative properties.Similarly,dietary flavonoids protect the human body against free radicals which are associated with the development of cancer and atherosclerosis.Plants rich in polyphenols have been used to cure various diseases because of their antibacterial,antiviral,antifungal and anticancer properties.This review summarizes the up-to-date research trends and development on flavonoids and its derivatives,working mechanisms and potential functions and applications particularly in relation to plant protection and human health.Towards the end,notable concluding remarks with a close-up look at the future research directions have also been presented briefly.

Comparison of Differences in Total Flavonoids between Leaves and Whole Plants of Anoectochilus roxburghii

[Objectives] To compare the differences in the total flavonoids between leaves and whole plants of Anoectochilus roxburghii.[Methods] The total flavonoids in the tissue cultured leaves and whole plants of A.roxburghii were extracted by microwave-assisted extraction.The content of total flavonoids in the extracts was determined by UV spectrophotometry.[Results]The results of the content determination showed that there were significant differences in the flavonoid content between the leaves and the whole plants of A.roxburghii.[Conclusions]The content of total flavonoids in tissue cultured leaves was higher than that of whole plants.Thus,in the development and utilization of A.roxburghii,tissue cultured leaves can be used to take the place of the whole plants.

植物类黄酮的分类、药理活性及其生物合成调控研究进展

类黄酮是植物中重要的次生代谢产物之一,包括黄酮、黄酮醇、异黄酮、黄烷酮、黄烷醇、查尔酮、花青素和原花青素等,在植物生长发育和逆境胁迫响应过程中发挥重要作用,同时具有抗氧化、抗衰老、抗菌消炎等药理活性。植物类黄酮的生物合成主要受两类基因控制,一类是直接编码类黄酮合成相关生物酶的结构基因,另一类是调控这些结构基因表达的转录因子。本文对植物类黄酮的种类、药理活性及其生物合成调控研究进展进行了综述,并探讨了今后的研究趋势,以期为植物类黄酮的研究和开发应用提供科学依据。

Phytochemical Screening of Some Medicinal Plants in Al Jouf, KSA

The utilization of ethnobotanical and phytochemical investigations in the discovery of novel medications is beneficial. Screening for phytochemicals is an important step in detecting the bioactive ingredients of medicinal plants which are used in conventional therapy. For the first time, 23 medicinal plants utilized in Saudi Arabian traditional therapy were examined. From August 2020 to July 2021, ethnobotanical fieldwork was conducted. There was some plant species identified, divided into pertinent families. Standard procedures were used to screen these medicinal plants for the occurrence of glycosides, alkaloids, saponins, resins, saponins, tannins, and flavonoids. Among the medicinal plants used, the most common phytochemicals were alkaloids (95.65%), glycosides (86.96%), saponin (82.61%), tannins (73.91%), flavonoids (56.52%), and resin (52.17%). The least widely distributed chemicals, on the other side, were resins. Trigonella foenum-graecum L., Pimpinella anisum L., and Cuminum cyminum L. seeds were shown to contain all six categories of secondary metabolites. The ethnographic importance of these medicinal plants is consistent with the content of secondary metabolites.

代谢组学揭示茶树嫁接黄酮类物质代谢通路

以茶树品种“云桃”嫁接前后的一芽二叶为试材,采用代谢组学方法,研究了茶树嫁接过程中黄酮类物质的代谢机制,以期为深入探索茶树嫁接的黄酮代谢途径提供参考依据。结果表明:未经过嫁接的“云桃”和嫁接后的接穗“云桃”共检测到804个代谢物,其中黄酮类代谢物有213个。经过嫁接后,“云桃”中有25个黄酮类代谢物含量增加,9个含量减少。与黄酮类差异代谢物相关的富集通路主要有花青素生物合成、类黄酮生物合成、异黄酮生物合成、黄酮和黄酮醇生物合成。

林下种植蜜花豆生长早期的类黄酮化合物含量特征

【目的】探明林下人工栽培蜜花豆(鸡血藤)生长表现和主要药用成分含量的相关性,为林下蜜花豆种植管理及其采收提供参考依据。【方法】采用高效液相色谱法(HPLC法)测定3年生蜜花豆藤茎不同径级、分枝等级和保存方式下5种类黄酮化合物(原儿茶酸、儿茶素、表儿茶素、甘草素和芒柄花素)含量,结合方差分析、主成分分析及曲线回归等方法分析类黄酮化合物在不同处理水平间的差异及变化趋势。【结果】除表儿茶素外,其余4种化合物在蜜花豆不同径级藤茎间均存在显著差异,随藤径级增大,原儿茶酸、儿茶素和芒柄花素含量呈线性增加,甘草素含量呈非线性下降;原儿茶酸、甘草素和芒柄花素含量在蜜花豆不同分枝等级间存在显著差异,随分枝等级增加,原儿茶酸、儿茶素、芒柄花素及表儿茶素含量降低,甘草素含量则增加;蜜花豆藤茎风干样中儿茶素、表儿茶素含量显著高于冷藏鲜样。【结论】原儿茶酸、儿茶素和芒柄花素主要在木质部富集,甘草素则主要存在于非木质部组织,蜜花豆风干保存有利于富集儿茶素和表儿茶素。

植物类黄酮的生理功能及其在家禽生产中的应用

植物类黄酮作为多酚类天然化合物具有一定的抑菌、消炎、抗氧化、抗肿瘤等生物学功能,能够调节机体的免疫力,具有类雌激素样作用。植物类黄酮常用于人的药品和功能性食品领域,作为一类绿色新型饲料添加剂在畜禽生产中也得到了推广应用。本文仅就植物类黄酮的结构、分类、生理功能及其在家禽生产中的应用进行综述。

植物黄酮类对家禽生长的调节作用

植物提取物通常均具有易获取且安全,无毒的作用。其中黄酮类物质则具有调节鸡脂质代谢、激素分泌,提高免疫能力以及蛋肉品质等多种功效。文章主要综述了自2012年以来关于对鸡生产效能的调节作用以及原料易获取的几种植物黄酮,旨在为其能否成为日粮添加剂提供参考价值。

正交设计优选广西钩藤总黄酮的提取工艺及抗氧化活性研究

目的:优化广西钩藤总黄酮的超声波辅助提取工艺,并检测其体外抗氧化活性。方法:采用UV法检测钩藤总黄酮含量;以总黄酮提取率为考察指标,采用正交设计法优化钩藤总黄酮的超声波辅助提取工艺条件;利用DPPH法检测乙醇提取物清除DPPH的活性。结果:采用超声波辅助提取法提取两次,超声功率360 W,最佳提取工艺为60倍量60%乙醇、超声提取30 min、提取温度70℃;在0.05~0.25 mg/mL范围内,随总黄酮提取物浓度的增加,提取物对DPPH的清除率增大;当提取物浓度为0.25 mg/mL时,柳州、梧州、钦州、玉林和桂林等5个产地的钩藤总黄酮对DPPH的清除率均在85%以上,分别为92.0%、91.6%、86.9%、90.8%、85.7%和97.3%。结论:该提取工艺稳定可行,可作为钩藤总黄酮的提取工艺;钩藤黄酮醇提取物对DPPH具有清除作用,可为钩藤黄酮的深入开发提供参考。

豆科山蚂蝗属植物的化学成分及生物活性研究进展

豆科(Leguminosae)山蚂蝗属(Desmodium)植物在我国分布广泛,种类较多,常作为药用植物应用于传统中药,因其药效显著,在民间使用广泛.该属植物主要有黄酮、生物碱、萜类、挥发油等化学成分;通常发挥抗炎、抗氧化、抗菌、清除体内氧自由基、保肝、镇痛等生物活性.我们通过对山蚂蝗属植物包括广金钱草、小槐花、饿蚂蝗、三点金、小叶三点金、大叶山蚂蝗、肾叶山蚂蝗、长柄山蚂蝗、假地豆等所含化学成分以及生物活性研究进行综述,旨在为山蚂蝗属植物的深入研究提供理论依据.

油用山茶属植物的次生代谢成分及药理作用研究进展

按照酚类化合物、萜类化合物及含氮化合物分类归纳总结了油用山茶属植物的次生代谢产物,并讨论了其抗氧化、抗炎、防紫外辐射等功能及其作用机理,为其在食品与化妆品等行业中的充分利用提供方向.

闽南地区19株野生茶树主要活性成分研究

为进一步开发、利用闽南野生茶树资源,采用传统醇提法提取泉州市境内19株野生茶树叶片中的总黄酮,分析不同野生茶树叶片总黄酮含量及其抗氧化活性、儿茶素类物质含量及其种类变化。结果表明,19株野生茶树的总黄酮含量差异较大,部分野生茶树之间差异显著;19株野生茶树的总黄酮提取液对DPPH自由基均具有较强的清除能力,有15株野生茶树对·OH自由基清除能力呈现较高水平,部分野生茶树群体间对DPPH和·OH的清除率存在显著性差异,处于同一生长环境的不同野生茶树的清除率也存在较大差异,其中TK-2对DPPH和·OH的消除能力均为最强;19株野生茶树在儿茶素组成上差异较大,表现出丰富的多样性,都不属于高EGCG的种质资源;HL-1、ST-1、ST-3、ST-5的茶叶品质相对较好,HL-1、HL-2、HL-3和HL-4可作为儿茶素提取的优质原料品种。综上,研究表明分布于闽南地区19株野生茶树的黄酮含量、儿茶素含量,以及抗氧化活性有显著差异,且表现出单株特异性,研究结果可为合理开发利用和选育优良品种提供优良材料。

黄酮类化合物在植物保护领域的研究进展

黄酮类化合物是重要的植物次生代谢物,可以增强植物抗逆性,如抗紫外线、抗低温、抗干旱、抗盐、抗菌、抗病毒、抗虫害、抗杂草等,进而保护植物免受生物或非生物胁迫导致的损伤,其植物抗逆性研究有助于植物保护领域的理论创新与技术突破。在黄酮类化合物植物抗逆性理论研究的基础上,可以提取富集植物源活性黄酮类化合物,并以其为原药开发生物农药,或以活性黄酮类化合物为先导,结合化学结构修饰与活性评价筛选活性更强的先导化合物用以研发新型绿色农药。系统综述了近年来国内外黄酮类化合物在植物保护领域的研究进展,可为后续相关理论及应用研究提供参考。

仿野生种植三叶青不同部位总黄酮分析及其抗炎、抗氧化能力比较

目的:比较仿野生种植三叶青不同部位中总黄酮含量、抗氧化活性以及抗炎能力差异。方法:采用醇提工艺对仿野生种植三叶青茎叶、块根、根须进行提取,比较不同部位间总黄酮含量差异;通过DPPH自由基、ABTS^(+)自由基、羟自由基清除实验以及铁离子还原力测定,比较仿野生种植三叶青不同部位间抗氧化能力的强弱;采用脂多糖(LPS)诱导RAW264.7细胞作为炎症模型,通过细胞NO的释放量比较仿野生种植三叶青不同部位间的抗炎能力差异。结果:在最佳提取工艺条件下,测得仿野生种植三叶青茎叶、块根、根须总黄酮含量分别为11.86±0.23、8.48±0.10、7.52±0.02 mg·g^(-1);建立三叶青HPLC指纹图谱,共标定了10个共有峰,通过对照品指认出6号峰为芦丁、8号峰为槲皮素、9号峰为山奈酚,并对其含量进行检测,结果显示块根中三种指标成分含量均最高,其次根须,茎叶最低。检测仿野生种植三叶青不同部位对DPPH自由基、ABTS^(+)自由基以及羟自由基的IC_(50)值,茎叶分别为0.2107、0.2315、0.7625 mg/mL;块根分别为0.3134、0.3758、0.8967 mg/mL;根须分别为0.2058、0.2587、0.7856 mg/mL。三叶青茎叶、块根、根须对铁离子还原能力的吸光度值分别为0.172、0.153、0.184。当仿野生种植三叶青三部位的质量浓度在25~200μg/mL之间时,它们不会对RAW264.7细胞造成毒性,能够有效地抑制LPS诱导的NO释放,从而达到良好的抗炎效果。结论:本研究结果为仿野生种植三叶青不同部位的质量评价提供参考,并对仿野生种植三叶青非药用部位废物再利用及后续全资源开发提供理论依据。

In vitro screening for acetylcholinesterase inhibition and antioxidant activity of medicinal plants from southern Africa

Objective:To determine the acetylcholinesterase inhibitory（AChE1） and antioxidant activity of the ethyl acetate and methanol extracts of 12 traditional medicinal plants used in the treatment of neurological disorders.Methods:AChEI activity was determined spectrophotometrically using the Ellman’s colorimetric method.Antioxidant activity was carried out by determining the ability of the extracts to scavenge 2,2-diphenyl-1-picryl hydrazyl（DPPH） and 2,2’-azinobis- 3-ethylbenzothiazoline-6-sulfonic acid（ABTS） radicals.The levels of total phenols,flavonoids and flavonols were determined quantitatively using spectrophotometric methods.Results:AChEI was observed to be dose-dependent.Lannea schweinfurthii（L.schweinfurthii）（Engl.） Engl.and Scadoxus puniceus（S.puniceus）（L.） Friis & I.Nordal.root extracts showed the lowest IC50 value of 0.000 3 mg/mL for the ethyl acetate extracts while Zanthoxylum davyi（Z.davyi）（I.Verd.） P.G. Watermann had the lowest IC50 value of 0.01 mg/mL for the methanol extracts in the AChEI assay. The roots of Piper capense（P.capense） L.f.,L.schweinfurthii,Ziziphus mucronata（Z.mucronata） Willd.,Z.davyi and Crinum bulbispermum（C.bulbispermum）（Burm.f.） Milne-Redh.& Schweick.showed noteworthy radical scavenging activity and good AChEI activity.Conclusions: Five plants show good antioxidant and AChEI activity.These findings support the traditional use of the plants for treating neurological disorders especially where a cholinesterase mechanism and reactive oxygen species（ROS） are involved.

天然化合物黄酮抗炎作用信号通路机制研究进展

长期的炎症若不加以干预可能会引起组织器官损伤,给患者的健康带来巨大危害。目前临床上公认的治疗炎症的非甾体类抗炎药存在着不良反应较大的争议,因此疗效确切但不良反应较小的替代药物成为新药研究的热点话题。黄酮是具有抗炎活性的最常见的一类化合物,近些年来对其抗炎作用信号通路机制的研究日益丰富,如抑制相关激酶磷酸化和基因核转录等机制。通过总结国内外黄酮类化合物有关抗炎作用的体内外实验研究文献,总结该类化合物发挥抗炎作用的可能信号通路机制,旨在为药物理论研究提供借鉴,为抗炎新药研制提供参考。

植物源性天然抗氧化剂的机理及其在食品保鲜中的应用

逐渐兴起的养生理念使有着“无毒”“天然”“绿色”等热点词汇的植物源性天然抗氧化剂脱颖而出。植物源性抗氧化剂是一类来源于植物的天然抗氧化物质,与合成抗氧化剂相比具有天然、高效等特点,作为天然食品防腐剂被广泛应用于食品保鲜。文章主要针对常见的植物源性抗氧化剂的种类、作用机理以及它们在食品(如肉类、果蔬、酒类、豆类等)保鲜中的应用进行了综述。此外,还探讨了天然植物源性抗氧化剂的特点以及该领域亟待解决的问题,为植物源性抗氧化剂在食品保鲜中的良好应用前景提供了参考,奠定了理论基础。

Antioxidant and antimicrobial properties of five medicinal Libyan plants extracts

Five Libyan medicinal plants Thapsia garganica, Hammada scoparia, Euphorbia serrata, Hyoscyamus albus and Retama rateam were selected to evaluate their biological activities. Their total phenolic and flavanoid contents were assessed. The antioxidant activity was estimated using 2, 2-di- phenyl-1-picrylhydrazyl (DPPH) as free radical scavenger. Their crude extracts showed reducing potential proportional to their concentration. The correlation coefficient (R2) between antioxidant activity and their total phenolics and flavanoids content is 0.77 and 0.98 respectively. Crude aqueous, methanolic as well as alkaloids extracts of the five plants were tested against a number of G+ve and G-ve sensitive resistant (e.g MRSA) bacteria beside some fungal species. The aqueous extracts displayed weak antibacterial activity whereas methanolic extracts were profoundly effective against both G+ve and G-ve bacteria. The extracts of E. serrata and H. scoparia were highly effective against E. coli in particular. The alkaloid-rich extracts of H. albus and H. scoparia induced remarkable bacteriostatic and fungistatic effects. The bioactive ingredients of H. scoparia, E. serrata and R. rateam extracts are shown to be potential sources of natural antioxidant and antimicrobial ingredients favoring their possible use in industrial pharmacology on large scale.

Cultivation characteristics and flavonoid contents of wormwood (Artemisia montana Pamp.)

The aim of this study was to establish the optimum harvesting time and the content of flavonoids in the leaves, stems, and roots of Artemisia montana Pamp. A. montana was monitored from June to October in 2012. The yield of A. montana at high density (30 × 10 cm) was higher than that of A. montana at low density (30 × 20 and 30 cm). Yield in terms of dry weight was increased with an extended growth period and development stage. High yield achieved at 2580 and 2757 kg?10 a?1 in September and October, respectively. Among the leaves, stems, and underground plant organs, jaceosidin and eupatilin were mainly detected in the leaves, and the highest levels were observed in June, at values of 66.6 and 158.2 mg?100 g?1, respectively. In contrast, apigenin was the major compound detected in the underground plant organs, with levels ranging from 21.2 to 29.5 mg?100 g?1 until September. Therefore, optimal harvest times were between September and October, generating a high yield and adding economic value although a higher level of total flavonoids was observed in crops harvested in June.