Characterization and antioxidant activities of procyanidins from lotus seedpod,mangosteen pericarp,and camellia flower

A highly sensitive high-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight mass spectrometry method was established for the identification of procyanidin components in the lotus seedpod, mangosteen pericarp, and camellia flower. It was shown that the main procyanidins of lotus seedpod were monomer, dimmer, and trimer-procyanidins, in which dimers and trimers were in the majority (80.8%). However, mangosteen pericarp and camellia flower procyanidins were mostly composed of monomers (47.7 and 62.4%, respectively). In addition, their antioxidant activities were also compared and the strongest antioxidant activities were found in lotus seedpod (1,1-diphenyl-2-picrylhydrazyl: 1.57 μmol Trolox equivalent/g dry weight; 2’-azino-bis-(3-ethyl-benzthiazoline-6-sulphonate acid): 1.23 μmol Trolox equivalent/g dry weight; Fe²⁺/H₂O₂: 2.17 μmol Trolox equivalent/g dry weight), followed by mangosteen pericarp and camellia flower. Moreover, the lotus seedpod, mangosteen pericarp, and camellia flower extracts exhibited considerable dose-dependent protective effects on the H₂O₂-induced damage of human umbilical vein endothelial cells. Among them, lotus seedpod extracts showed relatively stronger cell-based antioxidant enzyme activities and lower contents of malondialdehyde and nitric oxide than those of camellia flower and mangosteen pericarp. From these results, lotus seedpod, mangosteen pericarp, and camellia flower would be available agricultural wastes and their utilization may produce easier access of functional ingredients for medicinal exploration.     

白莲莲房多糖分离纯化、结构表征及抗氧化与免疫活性

以白莲莲房为原料,采用水提醇沉法获得白莲莲房粗多糖,再采用Sevage试剂脱蛋白、联合脱色和透析法对白莲莲房粗多糖进行纯化,得到白莲莲房多糖。采用红外光谱以及气相色谱对莲房多糖的理化性质进行了研究。通过还原能力测定、DPPH自由基和羟基自由基的清除能力评价白莲莲房多糖的体外抗氧化能力;以小鼠巨噬细胞RAW 264.7为模型,考察白莲莲房多糖对细胞的免疫调节活性。结果表明,所得白莲莲房多糖的得率为5.29%,多糖质量分数为84.58%;白莲莲房多糖单糖组成分析表明,白莲莲房多糖是一个杂多糖,由鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖、半乳糖组成,其摩尔比为1.28∶2.10∶1.00∶2.20∶2.42∶4.76。红外光谱分析表明白莲莲房多糖呈现出多糖类物质的典型特征吸收峰。体外抗氧化试验结果表明,白莲莲房多糖具有良好的还原能力和清除DPPH、羟基自由基的能力。免疫活性结果表明白莲莲房多糖显著促进巨噬细胞一氧化氮和炎症因子（TNF-α、IL-6、IL-1β）的分泌,在安全浓度范围内,白莲莲房多糖质量浓度为100 μg/mL时,NO、TNF-α、IL-6和IL-1β的分泌量达到了最大值,与空白组相比,NO、TNF-α、IL-6和IL-1β的分泌量分别增加了29.89 μmol/L、84.24 ng/mL、33.89 ng/mL和45.96 ng/mL。白莲莲房多糖可作为一种潜在的功能性食品免疫调节剂或补充剂。     

Characterisation of the chemical composition and in vitro anti-inflammation assessment of a novel lotus (Nelumbo nucifera Gaertn) plumule polysaccharide

Lotus plumule has been recognised as an anti-inflammatory agent. A novel lotus plumule polysaccharide (LPPS) was prepared, characterised and cultured with splenocytes from non-obese diabetes (NOD) and BALB/c mice (as a control) to further evaluate its anti-inflammatory effects in this study. The results showed the molecular weights of LPPS respectively distributed at 391 kDa (89.8 ± 0.5%) and 5 kDa (10.1 ± 1.5%) using HPLC analysis. The neutral sugar composition in LPPS comprised xylose (33.4 ± 10.0%), glucose (25.7 ± 1.6%), fructose (22.0 ± 15.0%), galactose (10.5 ± 3.3%), and fucose (8.1 ± 3.5%). LPPS administrations at appropriate concentrations significantly (P < 0.05) increased interleukin (IL)-10, IL-6, tumour necrosis factor (TNF)-α secretions by splenocytes from both NOD and BALB/c mice at ages of 15, 22 and 26 weeks, respectively. However, LPPS administrations markedly (P < 0.05) increased secretion ratios of anti-/pro-inflammatory (IL-10/IL-6) cytokines by splenocytes. The present study suggests that LPPS may have potential to treat type 1 diabetes via its potent anti-inflammatory activity.     

莲房原花青素的提取纯化技术研究

对莲房原花青素的提取纯化工艺条件进行了研究,得到较优提取工艺为：提取温度50℃,提取溶剂60%乙醇,料液比1：30,提取时间30min。采用大孔吸附树脂D-101、DA-201、DM-301和聚酰胺树脂对原花青素进行纯化,结果表明,大孔树脂DA-201对莲房原花青素有较好的吸附和洗脱效果,以70%乙醇为洗脱剂,初步得到纯化的莲房原花青素,洗脱率为84.1%。     

The effects of Caulerpa microphysa enzyme-digested extracts on ACE-inhibitory activity and in vitro anti-tumour properties

The aim of this study was to determine the ACE inhibitory activity and its anti-cancer properties of Caulerpa microphysa extracts. C. microphysa samples were digested with Flavourzyme, Alcalase, and pepsin. The ACE inhibitory activity of enzyme-digested C. microphysa decreased in the order of digestion with pepsin > Flavourzyme > Alcalase; that is, pepsin-extracted samples had significantly higher activity than the other enzyme extractions. To test its anti-tumour effects in vitro C. microphysa pepsin-digested extracts were applied to BALB/c mice with transplanted myelomonocytic leukaemia (WEHI-3) and Human promyelocytic leukaemia (HL-60) cell lines. The growth of both cell lines was inhibited, and extracts induced DNA damage, evaluated with a comet assay. The data demonstrate that C. microphysa pepsin-digested extract had the ability to anti-tumour effects. Further application as a health food is worthy of investigation.     

The thermostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: Investigation in vitro

This research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of their bioactive compounds, antioxidant activity and thermostability.It was found that polyphenols (mg GAE/g), flavanols (μg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots were 14.18 ± 0.7, 8.41 ± 0.5, 1.09 ± 0.06, 21.3 ± 1.2 and 7.29 ± 0.4, and of white onion - 11.11 ± 0.6, 6.78 ± 0.3, 0.71 ± 0.03, 17.00 ± 0.9 and 1.64 ± 0.08, respectively, and significantly higher in KLR (P < 0.05). The antioxidant activity of raw KLR water extract (139.4 ± 6.1, 53.1 ± 3.6 and 89.3 ± 4.6 μmol TE/g for DPPH, CUPRAC and ABTS, respectively) was significantly higher than in white onion (23.84 ± 1.8, 31.9 ± 2.1 and 38.14 ± 2.6 for DPPH, CUPRAC and ABTS, respectively, P < 0.05).The thermostability of the water KLR extract’s of polyphenols, flavanols, flavonoids, anthocyanins and tannins was high and even after 60 min of boiling remains as 40.0, 42.3, 50.5, 41.4 and 41.0%, respectively. After 60 min of boiling the most thermostable compounds were flavonoids - remaining at 50.5% in water extract of KLR. Also after 60 min of boiling the thermostability of the antioxidant activity of water extracts of KLR remained significantly high: 40.6, 42.3, 46.3 and 43.6%, according to DPPH, FRAP, ABTS and CUPRAC assays, respectively.Similar relationship was obtained with acetone extracts, but the value was lower than with the water ones. In conclusion, the contents of some bioactive compounds, the antioxidant activity and the thermostability in water and acetone extracts of KLR are significantly higher than the same indices in PWO. FTIR and fluorimetry can be used as additional markers for the characterization of bioactive compounds in vegetables.     

Inhibition of reactive nitrogen species invitro and exvivo by thioredoxin h2 from sweet potato ‘Tainong 57’ storage roots

In this study, the ability of thioredoxin h2 (TRX h2) expressed in Escherichia coli to scavenge ON and ONOO⁻ were investigated. The data obtained show that TRX h2 generated a dose-dependent inhibition on production of nitrite and superoxide radicals. TRX h2 also caused a dose-dependent inhibition of the oxidation of dihydrorhodamine 123 (DHR) by peroxynitrite. Spectrophotometric analyses revealed that TRX h2 suppressed the formation of ONOO⁻-mediated tyrosine nitration through an electron donation mechanism. In further studies, TRX h2 also showed a significant ability of inhibiting the nitration of bovine serum albumin (BSA) in a dose-dependent manner. In vivo TRX h2 inhibited LPS-induced nitrite production in macrophage in a concentration-dependent manner. The present study suggested that TRX h2 had an efficient reactive nitrogen species scavenging ability. TRX h2 might be a potential effective NO and ONOO⁻ scavenger useful for the prevention of the NO and ONOO⁻ involved diseases.     

Inhibition effects and induction of apoptosis of flavonoids on the prostate cancer cell line PC-3 in vitro

Myricetin and myricitrin are naturally occurring flavonoids have been suggested to play a role in inhibition of proliferation and transformation of carcinogenic cell. However, the underlying molecular mechanisms of their activity have not yet to be revealed. The aim of the present study was to clarify the molecular mechanisms of apoptosis cell on the prostate cancer induced by myricetin, myricitrin, quercetin and quercitrin. The MTT assay confirmed that myricetin had the strongest inhibitory effect on human prostate cancer cell line PC-3, myricitrin was second, and quercitrin was the weakest. A noticeable synergistic effect was observed with the inhibition of cell proliferation when myricetin was used in combination with myricitrin. In the concentration range of 37.5–300 μmol/L, the inhibitory effects of these flavonoids were enhanced with increasing dose and treatment time. The acridine orange analysis and annexin V–FITC/PI double-staining results confirmed that myricetin and myricitrin were effective in inducing PC-3 cell apoptosis. The results showed that myricetin was more effective than myricitrin in inducing cell apoptosis. The apoptosis rate increased with increasing flavonoid concentration in a dose dependent manner. A synergistic effect was observed on the apoptosis rate when myricetin was used in combination with myricitrin.     

Hibiscus sabdariffa leaf induces apoptosis of human prostate cancer cells in vitro and in vivo

Hibiscus sabdariffa leaf, the edible part of H. sabdariffa Linne, is usually ignored and discarded. The object of the study was to examine the anticancer properties of H.sabdariffa L. leaf extract (HLE). First, HLE was demonstrated to be rich in polyphenols, including catechin and ellagic acid (EA). 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) data showed that among three kinds of human prostate cancer (CaP) cells, androgen-dependent LNCaP cells were the most susceptible to HLE. HLE and its purified compound EA were evaluated for apoptotic activities. Molecular data showed the effect of HLE in LNCaP cells might be mediated via both intrinsic and extrinsic apoptotic pathways. Finally, HLE inhibited the growth of LNCaP cells in xenograft tumour studies. As a result, our data presented the first evidence of HLE as an apoptosis inducer in LNCaP cells, and these findings may open interesting perspectives to the strategy in human CaP treatment.     

Preparation,identification and their antitumor activities in vitro of polysaccharides from Chlorella pyrenoidosa

Ultrafiltration membranes of different pore size were applied to fractionate Chlorella pyrenoidosa polysaccharides (CPPS) and the main fraction could be separated by a membrane with nominal molecular weight cut-off (NMWCO) of 30 kDa. Ultrafiltration parameters of 40 °C 14.0 psi were optimized for obtaining the main fraction. The resulting sample was further purified by anion-exchange chromatography and size exclusion chromatography, and two distinctive polysaccharides, CPPS Ia and IIa were recovered. CPPS IIa had infrared spectral characteristic of polysaccharides similar to CPPS Ia, and the symmetrical stretching peak at 1408–1382 cm⁻¹ was an indication of the presence of carboxyl groups. The peak molecular weights were 69658 Da and 109406 Da, for CPPS Ia and CPPS IIa, respectively. Both CPPS Ia and IIa were composed of rhamnose, mannose, glucose, galactose and an unknown monosaccharide. Galactose (relative mass 46.5%) was the predominant monosaccharide of CPPS Ia and in CPPS IIa, rhamnose (37.8%) was predominant. CPPS Ia and IIa presented significantly higher antitumor activity against A549 in vitro than did a blank control, in a dose-dependent manner. Both fractions might be useful for developing natural safe antitumor drugs from C. pyrenoidosa resources.     

Antioxidant activities of malt extract from barley (Hordeum vulgare L.) toward various oxidative stress in vitro and in vivo

The antioxidant activities of malt extract from barley were evaluated by various methods in vitro and in vivo. Scavenging effects on the hydroxyl and superoxide radicals, and protection against reactive oxygen species induced lipid, protein and DNA damage were evaluated. The d-galactose induced mouse aging model was used to evaluate ability of malt extract to behave as an antioxidant in vivo. The extract exhibited high antioxidant activities both in vitro and in vivo, evidenced by its ability to scavenge hydroxyl- and superoxide-radicals, high reducing power, and protection against biological macromolecular oxidative damage. Furthermore, malt extract prevented the decrease of antioxidant enzyme activities, decreased liver and brain malondialodehyde levels and carbonyl content, and improved total antioxidant capability in d-galactose-treated mice. In conclusion, these results demonstrate potential antioxidant activities and antiaging effect of malt, providing scientific support for the empirical use of malt as an antioxidant for diseases caused by reactive oxygen species.     

Quantification of the polyphenolic fraction and in vitro antioxidant and in vivo anti-hyperlipemic activities of Hibiscus sabdariffa aqueous extract

In the present study the quantification of the polyphenolic fraction, anthocyanins and other polar compounds, the antioxidant capacity and the anti-hyperlipemic action of the aqueous extract of Hibiscus sabdariffa has been achieved. Seventeen compounds were successfully quantified either by HPLC-DAD or HPLC-ESI-TOF-MS. Six of them were directly quantified by their corresponding standards, whereas the rest were indirectly quantified as equivalents using standards of similar compounds. The antioxidant capacity have also been estimated by comparing different assays, i,e, Trolox equivalent antioxidant capacity (TEAC), ferric reducing antioxidant power (FRAP), oxygen radical absorbance capacity (ORAC), and measurement of thiobarbituric acid reacting substances (TBARS). H. sabdariffa showed high reducing capacity in FRAP assay and significant capability to scavenge peroxyl radicals in the ORAC assay. Nevertheless, the extract exhibited poor efficacy to inhibit peroxyl radicals in lipid systems. The plant extract also exhibited the capacity to decrease serum triglyceride concentration on hyperlipemic mouse model.     

The effect of simulated digestion in vitro on bioactivity of wheat bread with Tartary buckwheat flavones addition

The antioxidant activity of bread enriched in an extract from the green parts of buckwheat plant (TBF - Tartary buckwheat flavones) was determined. The bread's quality was slightly decreased when 2.5% TBF was added; however, with an addition of 5% TBF caused a high decrease in the bread's quality. Despite the digestion stage, the content of total phenolic compounds were the lowest in the case of the samples from the control bread (without buckwheat addition). Despite the kinds of bread, the lowest content of total phenolics and flavonoids and the highest phenolic acids content were detected in the fluids after simulated saliva digestion. Despite the digestion stage, the highest antiradical activity, reducing power and ability to inhibition of lipid peroxidation was observed in the samples with a 5% TBF addition. The free radical scavenging activity grew along with the increase of buckwheat preparate addition and in the progress of the in vitro digestion. The maximum of reducing and chelating power in the control sample were observed after simulated saliva digestion, whereas in the case of bread with the TBF addition the highest reducing power was observed after simulated gastric digestion, and maximum of chelating power - after simulated intestinal digestion.     

莲房多酚提取工艺优化及其抗氧化活性研究

在单因素实验的基础上,通过正交实验优化了热回流提取莲房多酚的工艺,并通过测定其清除ABTS+自由基、DPPH自由基、OH自由基的能力,还原力,亚铁离子螯合活性及对大鼠脑匀浆脂质过氧化的影响,对莲房多酚的抗氧化活性进行综合研究。结果表明,热回流提取莲房多酚的最佳工艺参数为:乙醇浓度50%,料液比1∶25,提取温度80℃,提取时间为2h,最优条件下的得率是5.23%。莲房多酚的体外抗氧化实验表明莲房多酚对DPPH自由基、ABTS+自由基、OH自由基有很强的清除能力,对亚铁离子的螯合活性和还原力均较强,并能显著抑制大鼠脑匀浆脂质过氧化。本研究表明在该优化工艺下提取的莲房多酚具有较强的抗氧化活性。      

A comparative study of tocopherols composition and antioxidant properties of in vivo and in vitro ectomycorrhizal fungi

In aerobic organisms, the free radicals are constantly being produced during the normal cellular metabolism. The antioxidant properties of many organisms and particularly of wild mushrooms with their content in antioxidant compounds such as tocopherols, can detoxify potentially damaging forms of activated oxygen. Herein, a comparative study of tocopherols composition and antioxidant properties of in vivo (fruiting bodies) and in vitro (mycelia) ectomycorrhizal fungi: Paxillus involutus and Pisolithus arhizus. Tocopherols were determined by high performance liquid chromatography (HPLC) coupled to a fluorescence detector. The antioxidant properties were studied in terms of DPPH radical-scavenging activity, reducing power and inhibition of β-carotene bleaching. Fruiting bodies revealed the highest antioxidant properties, including scavenging effects on free radicals (EC₅₀ = 0.61 and 0.56 mg/ml) and inhibition of lipid peroxidation capacity (EC₅₀ = 0.40 and 0.24 mg/ml for P. involutus and P. arhizus, respectively), than mycelia produced in vitro cultures. Nevertheless, mycelia revealed higher levels of total tocopherols than fruiting bodies, and particularly P. arhizus mycelium proved to be a powerful source of γ-tocopherol (154.39 μg/g dry weight).     

In vitro antioxidant activity and in vivo anti-fatigue effect of loach (Misgurnus anguillicaudatus) peptides prepared by papain digestion

The in vitro antioxidant activity and in vivo anti-fatigue activity of loach peptide (LP) were determined. Results showed that LP contained the amino acids, which were expected to contribute to its antioxidant and anti-fatigue activities. LP could scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) (IC₅₀ 17.0 ± 0.54 mg/ml) and hydroxyl radicals (IC₅₀ 2.64 ± 0.29 mg/ml). It could chelate cupric ion and inhibit the lipid peroxidation in a linoleic acid emulsion system. It also prolonged the swimming time to exhaustion of mice by 20–28% compared to the control. It increased the levels of blood glucose (28–42% increase) and liver glycogen (2.3–3.0-fold increase). It decreased the levels of lactic acid and blood urea nitrogen by 10.9–27.5% and 8.6–17.5%, respectively. It also improved the endogenous cellular antioxidant enzymes in mice by increasing the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px). Therefore, LP can increase an endurance capacity and facilitate recovery from fatigue.