Deep eutectic solvent combined with ultrasound technology: A promising integrated extraction strategy for anthocyanins and polyphenols from blueberry pomace.

To avoid wasting blueberry pomace resources, deep eutectic solvents (DESs) were combined with ultrasound technology to establish an efficient green method for the recovery of anthocyanins and polyphenols from plant-derived by-products. Choline chloride:1,4-butanediol (molar ratio of 1:3) was chosen as the optimal solvent based on the screening of eight solvents and single-factor experiments. Response surface methodology was applied to optimize the extraction parameters: water content, 29%; extraction temperature, 63 °C; liquid-solid ratio, 36:1 (v/w). The yields of total anthocyanins and total polyphenols from the optimized extraction were 11.40 ± 0.14 mg cyanidin-3-glucoside equiv./g and 41.56 ± 0.17 mg gallic acid equiv./g, respectively, which were both significantly better than the yields achieved with 70% ethanol. The purified anthocyanins showed excellent inhibition of α-glucosidase (IC50 = 16.57 µg/mL). The physicochemical parameters of DES suggest that it can be used for the extraction of bioactive substances.

Interactions between tea polyphenols and nutrients in food.

Tea polyphenols (TPs) are important secondary metabolites in tea and are active in the food and drug industry because of their rich biological activities. In diet and food production, TPs are often in contact with other food nutrients, affecting their respective physicochemical properties and functional activity. Therefore, the interaction between TPs and food nutrients is a very important topic. In this review, we describe the interactions between TPs and food nutrients such as proteins, polysaccharides, and lipids, highlight the forms of their interactions, and discuss the changes in structure, function, and activity resulting from their interactions.

Ubiquinol is superior to ubiquinone to enhance Coenzyme Q10 status in older men.

Coenzyme Q10 (CoQ10) exerts its functions in the body through the ability of its benzoquinone head group to accept and donate electrons. The primary functions are to relay electrons for ATP production in the electron transport chain and to act as an important lipophilic antioxidant. Ubiquinone, the oxidized form of CoQ10, is commonly formulated in commercial supplements, and it must be reduced to ubiquinol to exert CoQ10's functions after consumption. Thus, we aimed to examine whether as compared to ubiquinone, ubiquinol would be more effective to enhance the CoQ10 status in older men. We conducted a double-blind, randomized, crossover trial with two 2-week intervention phases and a 2-week washout between crossovers. Ten eligible older men were randomized to consume either the ubiquinol or ubiquinone supplement at a dose of 200 mg d-1 with one of the main meals. A total of 4 blood samples were collected after an overnight fast for the determination of ubiquinone and ubiquinol in plasma and PBMC and the assessment of FRAP, total thiol, and malondialdehyde (MDA) in plasma and ATP in PBMC. After 2 weeks of the supplementation, the ubiquinol supplement significantly increased plasma ubiquinone 1.7 fold from 0.2 to 0.6 µmol L-1 and total CoQ10 (the sum of 2 forms) 1.5 fold from 1.3 to 3.4 µmol L-1 (p < 0.05) and tended to increase the plasma ubiquinol status 1.5 fold from 1.1 to 2.8 µmol L-1, but did not alter the ratio of ubiquinol to total CoQ10. The ubiquinone supplement insignificantly increases plasma ubiquinol, ubiquinone, and total CoQ10 and did not affect the ratio. Of 10 subjects, six were more responsive to the ubiquinol supplement and 2 were more so to the ubiquinone. The supplementation of both CoQ10 forms did not alter the CoQ10 status in PBMC. FRAP, total thiol, and MDA in plasma and ATP in PBMC were not changed during the intervention. The significant increase in plasma CoQ10 status observed after the 2-week supplementation suggested that ubiquinol appeared to be a better supplemental form to enhance the CoQ10 status than ubiquinone in older men. Neither ubiquinol nor ubiquinone supplement affected the measured biomarkers of oxidative stress.

Physicochemical properties and cell-based bioactivity of Pu'erh tea polysaccharide conjugates.

Polysaccharide conjugates were prepared from Pu'erh tea and fractionated by DEAE-cellulose DE-52 column chromatography to yield one unexplored polysaccharide-conjugate fraction termed TPC-P with a molecular weight of 251,200Da. DVS (dynamic vapour sorption) result discovered that the humidity condition of long-term preservation for TPC-P is below 70% RH. Although it contained proteins, TPC-P could not bind to the Coomassie Brilliant Blue dyes G250 and R250. The "shoulder-shaped" ultroviolet absorption peak in TPC-P UV-vis scanning spectum ascribe theabrownins that inevitably adsorbed the polysaccharide conjugate. Zeta potential results demonstrated TPC-P aqueous solution merely presented the negative charge properties of polysaccharides instead of acid-base property of its protein section, and had more stability in greater than pH 5.5. No precipitation or haze occurred in the three TPC-P/EGCG aqueous mixtures during their being stored for 12h. The phase separation was observed in aqueous mixtures of TPC-P and type B gelatin. TPC-P possessed the fine stability as a function of temperature heating and cooling between 0 and 55°C. It is proposed that some properties of the covalent binding protein of TPC-P were "shielded" by its polysaccharide chains.

Preventive Effects of Catechins on Cardiovascular Disease.

Catechins are polyphenolic phytochemicals with many important physiological activities that play a multifaceted health care function in the human body, especially in the prevention of cardiovascular disease. In this paper, various experimental and clinical studies have revealed the role of catechins in the prevention and treatment of cardiovascular disorders, and we review the preventive effects of catechins on cardiovascular disease from the following aspects: Regulating lipid metabolism, regulating blood lipid metabolism, vascular endothelial protection, and reducing blood pressure.

Effects of Danhong Injection (丹红注射液) and its main components on anticoagulation and fibrinolysis in cultured vein endothelial cells.

OBJECTIVE: To observe the effects of Danhong Injection (丹红注射液) and its main components, including daiclzein and hydroxysafflor yellow A (HSYA), on the anticoagulation, fibrinolysis, anti-apoptosis in hypoxia model of vein endothelial cells (VECs). METHODS: VECs were prepared and were put in a hypoxia environment, which consisted of mixed gas of 95% N and 5% CO mixed gas, when reached confluent culture. Five groups used different treatments, including normal control group, hypoxia group, daiclzein group, HSYA group and Danhong Injection group. The VECs were identified by fluorescence double labeling methods. The morphology was observed by a phase contrast microscopy. The effects of Danhong Injection, daiclzein and HSYA on 6 keto prostaglandin F1α (6-keto-PGF1α) level was measured by the method of radioimmunoassay (RIA). Superoxide dismutase (SOD) activity was tested by water soluble tetrazolium salt. The content of malondialdehyde (MDA) was measured by thiobarbituric acid. The activities of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor (PAI) were measured by the method of chromogenic substrate. The contents of endothelin (ET) and nitric oxide (NO) were detected by non-equilibrium RIA and enzymelinked immunosorbent assay. Cells apoptosis rate was determined by flow cytometry. RESULTS: Compared with the normal control group, the floating cells number, PAI activity, ET and MDA contents, and cells apoptosis rate in the culture solution of hypoxia group were all significantly increased, whereas the 6-keto-PGF1α and NO contents, and t-PA and SOD activities were decreased significantly (P<0.01). Compared with the hypoxia group, Danhong Injection markedly increased the 6-keto-PGF1α content and SOD activity, regulated PAI and t-PA activities, ET and NO contents, and decreased MDA content and cells apoptosis rate (P<0.05 or P<0.01). CONCLUSIONS: Danhong Injection and its main components played an important role in protecting primary VECs from hypoxic damage by regulating the secretion and vasomotor function of VECs. The function of Danhong Injection was most remarkable.

Rubipodanin A, the First Natural N-Desmonomethyl Rubiaceae-Type Cyclopeptide from Rubia podantha, Indicating an Important Role of the N9-Methyl Group in the Conformation and Bioactivity.

One new cyclic hexapeptide named rubipodanin A (1), which is the first identified natural N-desmonomethyl Rubiaceae-type cyclopeptide, together with six known Rubiaceae-type cyclopeptides (2-7) were obtained using the TLC cyclopeptide protosite detection method with ninhydrin from the roots and rhizomes of Rubia podantha. The cyclopeptide structures were elucidated by extensive spectroscopic analysis, including 1D-NMR, 2D-NMR, IR, UV and MS. The solution conformation and biological activities of 1 and RA-V (4) were evaluated, and the results demonstrated that the N9-methyl group plays a vital role in the maintenance of the conformation and bioactivity.

New cytotoxic naphthohydroquinone dimers from Rubia alata.

Two novel naphthohydroquinone dimers with unprecedented skeletons, rubialatins A (1) and B (2), were isolated from the herbal plant Rubia alata together with their precursor, mollugin (3). The structures were elucidated on the basis of NMR spectra and crystal X-ray diffraction. Compound 1, a racemate, was separated by chiral column chromatography, and the absolute configurations of the enantiomers were determined by the computational methods. Cytotoxicity of 1-3 was evaluated as well as the effect on the NF-κB pathway. Compound (+)-1 showed cytotoxicity and could inhibit NF-κB pathway. Meanwhile, 2 showed cytotoxicity and a synergistic effect with TNF-α on NF-κB activation.

Blood anticoagulation and antiplatelet activity of green tea (-)-epigallocatechin (EGC) in mice.

EGC was prepared from green tea polyphenols through column chromatography of a polyamide (3.6 × 40 cm). Three dosages of EGC (0.25, 0.5, 1.0 g kg(-1) d(-1)) were ingested respectively by ICR mice via gavage. Compared with the control group, group EGC0.5 (dosage, 0. 5 g kg(-1) d(-1)) and group EGC1.0 (dosage, 1.0 g kg(-1) d(-1)) presented significant inhibition on platelet aggregation in mice accompanied by 18.4 and 25.6% of inhibition ratio, respectively. The bleeding times (BT) of mice in group EGC0.5 and group EGC1.0 were significantly prolonged (P < 0.01) as well as blood clotting time (BCT) in group EGC1.0 (P < 0.05). All three dosages of EGC prolonged activated partial thromboplastin time (APTT) significantly (P < 0.01), but had no prominent effect on prothrombin time (PT) and fibrinogen level which indicated that the anticoagulation of EGC could not be attributed to the level decrease of coagulation factor such as fibrinogen. The results demonstrated that EGC had prominent antiplatelet activity and blood anticoagulation in a dose-dependent manner.

Development of sample preparation method for isoliquiritigenin, liquiritin, and glycyrrhizic acid analysis in licorice by ionic liquids-ultrasound based extraction and high-performance liquid chromatography detection.

An ionic liquid-based ultrasonic-assisted extraction (ILUAE) method had been used for the effective extraction of isoliquiritigenin (IQ), liquiritin (LQ) and glycyrrhizic acid (GA) from licorice. The ionic liquids with different cations and anions were investigated in this work and 0.5 M 1-butyl-3-methylimidazolium bromide solution was selected as solvent. In addition, the technical parameters including soaking time, solid-liquid ratio, ultrasonic power and time were optimized. Compared with the conventional solvent extraction, the proposed approach exhibited higher efficiency, which indicated the ILUAE was an efficient, rapid and simple sample preparation technique. There was no degradation of the target analytes had been observed at the optimum conditions which was evidenced by the stability studies performed with standard of IQ, LQ and GA. The proposed method also showed high reproducibility and was environmental friendly.

[Spectral analysis of crude tea polysaccharides extracted by different methods].

Crude tea polysaccharides (CTPS) were extracted from low-grade green tea, separately named CTPS-I by water-boiling extraction method and CTPS-II by compound enzyme method, and CTPS-III extracted from tea leaves by compound enzyme method. The content of saccharide and protein of them were determined. The homogeneity distribution and mass ratio of polysaccharides constituent were analyzed using HPGPC-ELSD, and there were 5, 4 and 7 kinds of homogeneous constituents accordingly in CTPS-I , II and III. There were six kinds of monosaccharide residues (rhamnose, arabinose, xylose, mannose, glucose and galatose) in CTPS confirmed by means of GC-MS. UV spectra discovered that CTPS-I had a distinctive peak absorption at 257 nm, while CTPS-II showed a shoulder-shaped peak absorption in 240-270 nm, and CTPS-III exhibited a weak double wave-shaped absorption in 250-360 nm. In addition, the mass ratio of free protein and nucleic acid in CTPS was determined. IR revealed the characteristics of tea polysaccharides complex including related protein and nucleic acid. CD spectra showed that their conformations in water were different.