<Emphasis Type="Italic">Borago officinalis</Emphasis> L. flower: a comprehensive study on bioactive compounds and its health-promoting properties

The herbal plant Borago officinalis L. flower were analysed for its bioactive compounds and antioxidant, antibacterial, anti-inflammatory and anticancer activities using different solvent polarities (methanol, ethanol and water). The RP-HPLC analyses of the methanolic extract confirmed the presence of phenolics (gallic acid, pyrogallol, salicylic acid, caffeic acid), flavonoids (myricetin, rutin) and isoflavonoid (daidzein). Besides, the major individual fatty acids of methanolic extract were α-linolenic, stearidonic, palmitic, linoleic and γ-linolenic acids. The methanolic extract possessed the highest antioxidant properties as compared to the ethanolic and water extracts. The flower methanolic, ethanolic and water extracts showed high, moderate and weak antibacterial activities against common human and foodborne pathogenic bacteria, respectively. Furthermore, the flower extracts showed weak anti-inflammatory in murine RAW 264.7 macrophage cells and low anticancer properties against human hepatic, prostate and colon cancer cells. This high-value flower could be considered as a source of putative antioxidant and antibacterial compounds to improve the human health and to be used as biopreservative in food and cosmetic industries.     

Chemical characterization of the medicinal mushroom Phellinus linteus (Berkeley & Curtis) Teng and contribution of different fractions to its bioactivity

Mushrooms are widely appreciated for their organoleptic qualities, being also recognized as good sources of bioactive compounds that provide antioxidant, antimicrobial and cytotoxic activities. Polysaccharides (including glucans) are often pointed out as the most bioactive compounds isolated from mushrooms, but other molecules such as triterpenoids, might also be highlighted for their bioactivity. In scientific research, when isolated compounds are used, potential synergistic effects might be lost. Accordingly, the bioactivity of Phellinus linteus was evaluated in selected fractions (polysaccharides, glucans and triterpenoids), as well as in the methanolic and ethanolic extracts. The best antioxidant and antibacterial activities were obtained with methanolic extract, while glucan and triterpenoid fractions gave the strongest antifungal activity. In contrast, ethanolic extract gave the best results in cytotoxic activity, indicating that the bioactive compounds present might act synergistically. The differentiated activity of P. linteus fractions and extracts could be useful to find antimicrobial, antioxidant and cytotoxic agents as alternatives to synthetic chemicals with application in agriculture, food industry or pharmacy.     

Bioactivity and chemical characterization in hydrophilic and lipophilic compounds of Chenopodium ambrosioides L.

The bioactive properties (antioxidant and antitumour activities, and hepatotoxicity) of the infusion and methanolic extracts of Chenopodium ambrosioides L., a plant commonly used in Portuguese folk medicine, were compared. The chemical composition in hydrophilic (sugars, organic acids and phenolic compounds) and lipophilic (fatty acids and tocopherols) fractions were determined. In general, the infusion revealed higher antioxidant activity, while the methanolic extract was the only one showing antitumour effects against colon, cervical and hepatocellular carcinoma cell lines. No toxicity in non-tumour cells was observed either for the infusion or the extract. The studied plant proved to be a good source of natural antioxidants and other bioactive compounds, which may have industrial use. As far as we know, this is the first detailed chemical characterization and bioactivity evaluation of C. ambrosioides methanolic extract and infusion.     

微波杀青制备桑茶及其细胞抗氧化作用研究

以桑鲜叶为原料,采用微波杀青工艺制备桑茶,并通过建立细胞模型研究微波杀青桑茶不同溶剂提取物抗氧化作用。结果显示:微波杀青桑茶不同溶剂提取物主要抗氧化成分多酚和黄酮类含量分别为26.53³7.67mg/g提取物和18.56²4.89mg/g提取物,细胞抗氧化活性大小为50%乙醇提取物>75%乙醇提取物>95%乙醇提取物>沸水提取物,且桑茶不同溶剂提取物的细胞抗氧化作用均存在剂量-效应关系;显著性分析表明50%⁷5%乙醇提取物细胞抗氧化能力显著高于沸水提取物和95%乙醇提取物（p<0.05）。细胞内抗氧化活性与提取物中多酚类和黄酮类含量相关性较弱,相关系数分别为0.216、0.129。表明不能用多酚类和黄酮类含量来衡量桑茶提取物细胞抗氧化能力。      

杏鲍菇乙醇提取物的抗氧化活性及成分分离鉴定

以杏鲍菇为原料,通过70%乙醇提取可溶性物质,通过体外抗氧化实验研究其乙醇提取物的抗氧化活性,通过高效液相色谱质谱联用技术（LC-MS）分析乙醇提取物的一些生物活性成分。对杏鲍菇乙醇提取物的成分分析表明,杏鲍菇乙醇提取物中蛋白质含量为2.41 mg/g（DW）,总糖含量为25.46 mg/g（DW）,多酚含量为12.03 mg/g（DW）,黄酮含量为1.53 mg/g（DW）。体外抗氧化实验表明,杏鲍菇乙醇提取物对1,1-二苯基-2-三硝基苯肼（DPPH·）、羟自由基（·OH）、超氧阴离子自由基（O2-）都具有一定的清除能力。结果表明随着杏鲍菇乙醇提取物的浓度增大,抗氧化活性也增加。杏鲍菇乙醇提取物清除自由基能力的大小顺序为:·OH>DPPH·>O2-,而且杏鲍菇乙醇提取物对脂质过氧化具有明显的抑制作用。利用HPLC对多酚类物质进行了分析,其中含有原儿茶酸和黄岑素,利用LC-MS进一步对多酚类物质进行分析,证实其中含有:奎宁酸、没食子酸、原儿茶素、香豆酸和肉桂酸。      

Caffeic acid derivatives,total phenols,antioxidant and antimutagenic activities of Echinacea purpurea flower extracts

This study evaluated the effects of ethanol concentration and extraction temperature on the quality of extracts obtained from freeze-dried Echinacea purpurea flowers. The antioxidant and antimutagenic effects of flower extract were also examined. The optimal extraction conditions for freeze-dried flowers were 50% aqueous ethanol and 65 °C extraction temperature, with extraction yield of 37.4%. The contents of total phenols, caffeic acid derivatives, and cichoric acid in freeze-dried extracts were 473.34 mg chlorogenic acid equivalents/g, 302.20 mg/g and 217.61 mg/g, respectively. The 50% ethanolic flower extract did not show toxicity and mutagenicity toward Salmonella typhimurium TA98 and TA100 with or without S9 mix. The ethanolic extract at 0.25–5 mg/plate exhibits a dose-dependent inhibitory effect against the mutagenicity of 2-aminoanthracene. Thus, freeze-dried E. purpurea flower ethanolic extract exhibits good antioxidant and antimutaginic activities.     

Antioxidant activity of extracts from Lavandula vera MM cell cultures

The antioxidant activity of methanolic and ethyl acetate extracts from Lavandula vera MM cell culture were evaluated by the Schaal oven test in bulk sunflower oil and by the DPPH radical method. The oil oxidation was followed by measuring the quantity of primary oxidation products (peroxide value). Authentic rosmarinic acid, caffeic acid and BHT were tested in parallel for comparison. Ethyl acetate extract much better protected the oil from oxidation than methanolic extract and its antioxidant efficiency was comparable to that of pure rosmarinic and caffeic acids and much stronger than that of BHT. Both cell culture extracts and the authentic phenolic acids were much stronger scavengers of DPPH free radical than BHT on an equimolar basis.     

Bioactive components analysis of two various gingers (Zingiber officinale Roscoe) and antioxidant effect of ginger extracts

Ginger, a medicinal herb with bioactive components, is now widely used. This study reports the information of bioactive components in two varieties ginger root (Zingiber officinale Roscoe), Guangdong-ginger (GG) and Chu-ginger (CG) available in Taiwan and compares their bioactive components and antioxidant properties using aqueous and ethanolic extract. The proximate analysis of both ginger rhizomes gave similar profiles. Total contents of organic acids were 37.33 and 91.06 mg/g dry weight for GG and CG, respectively, with oxalic and tartaric acids being two major acids. HPLC analysis revealed gingerols and shogaol in both ginger were similar but curcumin content was higher in GG. The essential oils exhibited similar volatile profiles and 60 and 65 compounds were identified for GG and CG, respectively. Among the essential oils major components were camphene, sabinene, α-curcumene, zingiberene, α-farnesene, β-sesquiphellandrene, neral, and geranial. The antioxidant effect of ginger ethanolic extracts were more effective than aqueous extracts in Trolox equivalent antioxidant capacity and Ferric reducing ability of plasma. Contrarily, ginger aqueous extracts were more effective in free radical scavenging activities and chelating abilities. Based on the results, two ginger rhizomes exerted protective effects and could be used as a flavouring agent and a natural antioxidant.     

In vitro antioxidant and anticancer activities of ethanolic extract of selenium-enriched green tea

Selenium-enriched green tea is now being increasingly produced in China and is well known as a bioactive beverage, due to its high content of active components. In this study, the antioxidant and anticancer activities of an ethanolic extract and an aqueous extract of Se-enriched green tea were investigated. The results indicated that the ethanolic extract possessed significantly higher antioxidant activity than the aqueous extract and the positive control α-tocopherol, by both α,α-diphenyl-β-picrylhydrazyl (DPPH) radical-scavenging and ferric thiocyanate (FTC) assays. The ethanolic extract inhibited the proliferation of human cervical adenocarcinoma HeLa cell and possessed a significantly higher antitumour activity than the aqueous extract and the positive control 5-fluorouracil (5-FU), in the dose range of 62.5–250 μg/ml. Moreover, the ethanolic extract could significantly inhibit the growth of lung carcinoma A549 and hepatoma HepG2 in a concentration-dependent manner, with IC₅₀ values of 278.6 μg/ml and 431.6 μg/ml, respectively. Selenium, tea polyphenols and polyphenols constituents, especially epigallocatechin gallate (EGCG), were significantly higher in the ethanolic extract than in the aqueous extract, which were possibly responsible for the higher antioxidant and antitumour activities of the ethanolic extract.     

Antioxidant activity and polyphenol contents in Brazilian green propolis extracts prepared with the use of ethanol and water as solvents in different pH values

Propolis is a natural product with a variable and complex chemical composition associated with its high concentration on polyphenolic compounds. The effect of pH variation (2.0, 3.0, 4.3, 6.0 and 8.0) during aqueous and ethanolic propolis extraction was studied for up to 10 days. Total phenols and flavonoids contents were measured for the extracts by spectrophotometric assays. Antioxidant activity was measured by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and ferric thiocyanate (FTC) methods. The best time of extraction was up to 5 days for all samples. Basic aqueous extracts (pH 8.0) resulted in a higher concentration of compounds than the extract without pH modification, reaching an increase of 160% in flavonoids and 25% in phenols. Ethanolic extracts with pH variation resulted in an extract with 50% less polyphenols and 6% less flavonoids than extract without pH modification. The antioxidant activity was highest for ethanolic extract at pH 4.3 and aqueous extract at pH 8.0 – almost 90% and 45%, respectively, in DPPH method – and was related to the level of polyphenols by Pearson's correlations.     

酸浆五种部位醇提物的活性比较研究

目的:探讨酸浆根、茎、叶、宿萼和浆果醇提物的抑菌、抗氧化、抗肿瘤和抑炎活性。方法:采用牛津杯法检测酸浆五种部位醇提物对金黄色葡萄球菌、大肠杆菌和枯草芽孢杆菌的抑菌活性;DPPH清除法检测其抗氧化活性;Alamar Blue法检测其对人乳腺癌细胞株MCF-7、MDA-MB-231和肝癌细胞株Bel7402的抑制效果;一氧化氮检测试剂盒测定其抗炎活性。结果:浆果对金黄色葡萄球菌和大肠杆菌的抑菌效果最好,叶对枯草芽胞杆菌抑菌活性较明显,抑菌圈分别为（16.63±0.49）、（14.97±0.37）、（15.83±0.29）mm。宿萼的抗氧化活性最高,浓度为5 mg/m L时对DPPH的清除率为96.79%±2.09%,基本和同剂量的VC效果相当。酸浆各部位醇提物对肿瘤细胞的抑制作用呈现浓度依赖性,其中根对MCF-7的抑制活性较强,宿萼对MDA-MB-231和Bel7402的活性较强,IC50分别为（31.46±1.49）、（48.84±1.69）、（65.48±1.82）μg/m L。叶的抗炎效果最佳,茎抗炎效果较弱,10μg/m L时NO产生量分别为11.01、27.73μmol/L。结论:酸浆具有一定的抑菌、抗氧化、抗肿瘤和抗炎活性,为酸浆的功能开发及活性成分分离提供一定的理论依据。      

Retention of antioxidant activity in gamma irradiated argentinian sage and oregano

The effect of 30 kGy of gamma radiation on the antioxidant activity of methanolic and aqueous extracts prepared from dry gamma irradiated sage and oregano were analysed. The antioxidant activity was characterised by DPPH radical test and by reducing power assay within an extract concentration range of 0–40 mg/ml of methanol or water. In addition, the total phenolic content in the extracts was determined. From the EC₅₀ estimated values, it was established that, by both methods, oregano extracts showed a higher antioxidant activity than sage extracts. Oregano extracts also showed a phenolic content significantly higher than sage extracts. A good correlation between the phenolic content and the antioxidant activity was also observed. The 30 kGy dose applied to dry sage and oregano for sanitization did not significantly affect the capacity to inhibit the DPPH radical or the reducing power, nor did it affect the total phenolic content of the methanolic and aqueous extract.     

Spent espresso coffee grounds as a source of anti-proliferative and antioxidant compounds

Disposal of spent espresso coffee grounds (SCG) is costly and leads to the loss of bioactive compounds that could be fractionated, in several applications. This work aimed to investigate phenolic profile, tocopherols, and antioxidant and anti-proliferative activities of SCGs ethanolic extracts from coffee powders differing in coffee provenience and composition (arabica/robusta). Tyrosol, detected for the first time in SCGs, was the most abundant phenolic measured (121–1084 mg/kg in the extract), along with 4-hydroxybenzoic acid and vanillin (885–1813 and 340–1103 mg/kg, respectively). Extract derived from 100% robusta from Guatemala (S7-R) showed the highest α- to β-tocopherol ratio of 1.2 and the highest antioxidant potential as evidenced by RACI and GAS values of −0.43 and 0.20, respectively. Moreover, S7-R showed a promising anti-proliferative activity toward human lung carcinoma cells (A549), with IC₅₀ value of 61.2 μg/mL comparable to that given by the positive control vinblastine (IC₅₀ value of 67.3 μg/mL).     

In vitro inhibitory effects of rosemary extracts on growth and glucosyltransferase activity of Streptococcus sobrinus

Rosemary (Rosmarinus officinalis L.) extract functions as an antioxidant and antimicrobial agent. In this study, we investigated in vitro effects of rosemary extracts on Streptococcus sobrinus growth and on its extracellular glucosyltransferase activity. The antibacterial activities of rosemary extracts were determined by the microdilution broth method. The minimum inhibitory concentrations of aqueous and methanolic rosemary extracts against S. sobrinus were 16 and 4 mg/ml, respectively. Glucosyltransferase activity was tested by incubating a crude enzyme preparation with sucrose and determining the amount of water-insoluble glucan formed. Both aqueous and methanolic extracts of rosemary markedly inhibited the formation of water-insoluble glucan. The 50% inhibitory doses of aqueous and methanolic extracts against the glucosyltransferases of S. sobrinus were 1.42 mg/ml and 0.34 mg/ml, respectively. Our results suggest that rosemary extract may prove effective for the inhibition of the growth of cariogenic oral streptococci.     

沙棘籽粕原花青素制备、体外抗氧化及细胞活力评价

本实验优化了沙棘籽粕原花青素的提取方法,条件为80%乙醇,提取温度35℃,液料比8∶1 m L/g,时间1.5 h,p H3.0,在该条件下的原花青素提取率为（97.31±0.48）mg/g沙棘籽粕;对提取得到的原花青素提取物进行了DPPH自由基和羟自由基清除能力实验,并分析得到IC₅0,发现沙棘籽粕原花青素提取物的DPPH自由基清除能力较维生素C强;羟自由基清除能力较弱;MTT法测定了沙棘籽粕原花青素提取物对小鼠B16黑色素瘤细胞活力的抑制作用,分析得到24、48、72 h处理时间下提取物IC₅0分别为542.78、199.25、82.58μg/m L。结论:沙棘籽粕提取物对小鼠B16黑色素瘤细胞具有一定的抑制作用,随着剂量和时间的增加,呈逐渐增强的趋势。      

南疆12种植物抗氧化成分的测定及其清除自由基作用研究

测定南疆阿拉尔地产12种植物中多糖、黄酮和多酚类抗氧化成分及其抗氧化活性,明确三种主要成分与其抗氧化活性的相关性。采用紫外光度分析法测定抗氧化成分的含量,采用DPPH自由基清除法测定其抗氧化能力。结果表明,供试植物中多糖、黄酮和多酚类物质含量丰富,具有较强的清除DPPH自由基的能力,其中清除能力较强的植物为灰绿藜（IC50=77．29±4．80μg／mL）、紫花苜蓿（IC50=85．27±6．10μg／mL）和车轴草（IC50=94．16±4．62μg／mL）。就活性成分而言,多糖对DPPH自由基的清除能力极显著,多酚的清除能力显著,黄酮的清除能力不显著。供试样品醇提液对DPPH自由基的清除能力均呈现剂量依赖性。不同属植物的有效成分含量及清除DPPH自由基能力均有差异。     

Protective effects of the crude extracts from yam (Dioscorea alata) peel on tert-butylhydroperoxide-induced oxidative stress in mouse liver cells

Researchers have shown that yam extracts contain antioxidative activity; however, there are few reports regarding the antioxidant activities of yam peel. The effects of water and 50% ethanolic extracts from Darsan yam (Dioscorea alata) peel on the oxidative status of tert-butylhydroperoxide (t-BHP)-treated mouse Hepa 1–6 and FL83B liver cell lines were investigated. The cytosols were analysed for H₂O₂ and malondialdehyde (MDA) levels and antioxidative enzymes activities, including superoxide dismutase, glutathione peroxidase (GPx) and catalase activities. Both water and 50% ethanolic extracts from yam peel did not affect cellular MDA level in t-BHP-treated cells, but they altered the level of H₂O₂. Water extract from yam peel amplified the t-BHP-induced cytotoxicity in Hepa 1–6 whilst the ethanolic extract showed protection in FL83B cells. GPx activity might play an important role in the protective effect associated with t-BHP-induced oxidative stress.     

Bioactive components and antioxidant properties of γ-aminobutyric acid (GABA) tea leaves

Various ethanolic concentrations (0–95%, v/v) and temperatures (25–95 °C) were used to extract γ-aminobutyric acid (GABA) tea leaves. Extraction yields, and contents of total phenols, various catechins, GABA, theanine, and antioxidant properties of extracts were determined. The 50% (v/v) ethanol at 50–95 °C gave higher yields (32.05–32.56 g dried extract/100 g dried tea leaves). The bioactive components and antioxidant properties of extracts were affected by the ethanolic concentrations and temperatures. Among catechins, epigallocatechin gallate was the main catechin in all extracts, followed by epigallocatechin, epicatechin, epicatechin gallate, gallocatechin and gallocatechin gallate. The 50–75% (v/v) ethanol at 75–95 °C gave higher contents of ester type (102.92–104.54 mg/g extract) and non-ester type (61.75–63.55 mg/g extract) catechins. Water at 50–75 °C gave higher GABA and theanine contents and higher chelating ability of extracts. The 75% (v/v) ethanol at 25–75 °C gave higher scavenging ability and reducing power of extracts. Based on dried tea extracts or leaves results obtained, the optimal extraction conditions to maintain the total contents of various catechins, GABA and theanine in the maximum level were 50% ethanol (v/v) and 75–95 °C.     

Antioxidant and antibacterial activities of Nephelium lappaceum L. extracts

Ether, methanolic and aqueous extracts of lyophilized rambutan (Nephelium lappaceum L.) peels and seeds were evaluated for phenolic contents, antioxidant and antibacterial activities. High amounts of phenolic compounds were found in the peel extracts and the highest content was in the methanolic fraction (542.2 mg/g dry extract). Several potential antioxidant activities, including reducing power, β-carotene bleaching, linoleic peroxidation and free radical scavenging activity, were evaluated. The peel extracts exhibited higher antioxidant activity than the seed extracts in all methods determined (P < 0.05). The methanolic fraction was found to be the most active antioxidant as shown by their 50% DPPH inhibition concentration, 4.94 μg/mL. The results indicated this fraction exhibited greater DPPH radical scavenging activity than BHT and ascorbic acid (0.32 g dry extract/g BHT or ascorbic acid). Antibacterial activity against eight bacterial strains was assessed by disc diffusion and broth macrodilution methods. All peel extracts exhibited antibacterial activity against five pathogenic bacteria. The most sensitive strain, Staphylococcus epidermidis, was inhibited by the methanolic extract (MIC 2.0 mg/mL).     

Phenolic Compound Identification and Antioxidant Capacity of Alperujo Extracts from Region del Maule,Chile

This study was carried out to determinate phenolic, flavonoid content, and antioxidant capacity in methanolic extract from three Alperujo varieties. Alperujo Barnea showed the highest concentration of phenols and flavonoid. The greater hydroxytyrosol content was obtained in the same extract (4.93 ± 0.37 µg/mg extract), whereas the greater tyrosol content (0.23 ± 0.012 µg/mg extract) was found in Arbequina extract. These results were correlated with the greatest radical scavenging and the highest inhibition of lipoperoxidation process observed in Barnea extract (IC₅₀ of 27.9 ± 1.04 µg/mL; IC₅₀ 22.8 ± 3.5 µg/mL, respectively). In spite of differences, alperujo extracts exhibited notable antioxidant capacities.