Factors Influencing the Effects of Theabrownin in Pu-erh Tea on Scavenging DPPH Radicals

[Objective] This study aimed to explore factors influencing the effects of theabrownin in Pu-erh tea on scavenging DPPH radicals. [Method] Taking Pu-erh tea as main research object, theabrownin in Pu-erh tea from tea piles with different times of mixture, stored for different years and processed by both the old and new techniques were extracted and isolated. And DPPH method was used to study the effects of theabrownin solution and tea liquor on scavenging radicals and their antioxidant activity. [Result] The result showed that the theabrownin content in Pu-erh tea from tea piles with one to four times of mixture revealed a first declining and subsequently rising trend. Under different pH conditions, the rates of DPPH radical scavenging of 1 mg/ml theabrownin solution made from tea piles with different times of mixture decreased gradually with the increase of pH, and all the rates were lower than that of the control vitamin C solution; the rates of DPPH radical scavenging of theabrownin from tea samples stored for different years and produced by different techniques dropped slowly within pH range 3.0-6.0; when pH was higher than 6.0, the rates of DPPH radical scavenging of theabrownin from tea samples produced by both new and traditional techniques in 2001 declined obviously, while the declining trend was not obvious in either the black tea or the Pu-erh tea produced by new technique in 2005. Under different theabrownin concentrations, the rates of DPPH radical scavenging of theabrownin solution made from tea piles with different times of mixture ascended as the concentration increased and the highest rate occurred in tea pile with four times of mixture, reaching up to 46.56%±0.88%; for tea samples stored for different years and produced by different techniques, the rates of DPPH radical scavenging of theabrownin rose gradually with the increase of the theabrownin concentration; the rate of radical scavenging of theabrownin in the black tea ascended obviously and that in Pu-erh tea was decreasing within the concentration range of 0.04 -0.06 mg/ml. At pH6.0, the DPPH radical scavenging ability of theabrownin in 0.1 mg/ml theabrownin solution and tea liquor containing 0.1mg/ml theabrownin from tea piles with different times of mixture ascended with the time of mixture; solution made from tea samples produced by different techniques in different years, the DPPH radical scavenging ability of theabrownin solution and tea liquor followed： Pu-erh tea produced by the new technique in 2001 ﹥ Pu-erh tea produced by the old technique in 2001﹥ Pu-erh tea produced by the new technique in 2005. And the DPPH radical scavenging ability of theabrownin in tea liquor containing 0.1 mg/ml theabrownin was higher than that in 0.1 mg/ml theabrownin Solution made from tea samples either with different times of mixture or produced by different techniques in different years. The above results indicated that many factor influenced the effects of theabrownin on eliminating DPPH radicals, including the time of fermentation, fermentation technique, years of storage, concentration and pH all had great influence on the effects of theabrownin on eliminating radicals. To ensure a good effect on scavenging radicals, it is better to prepare theabrownin at pH6.0 with concentration between 0.08 and 0.1 mg/ml for drinking. [Conclusion] Results of this study provide a basis for developing functional products of theabrownin from Pu-erh tea in the future.

Constituents from Aerial Parts of Bidens ceruna L. and Their DPPH Radical Scavenging Activity

A new chalcone glycoside, butein-4-methoxyl-4′-O-（6＂-O-acetyl）-β-D-glucopyranoside（2）, along with seven known compounds, namely, quercitrin（1）, luteolin-7-O-β-D-glucopyranoside（3）, butein-4＇-O-β-D-glucopyranoside（4）, butein-4-methoxyl-4＇-O-β-D-glucopyranoside（5）, butin-7-O-β-D-glucopyranoside（6）, isoquercitrin（7）, and sulfurein（8） was isolated from aerial parts of Bidens ceruna L. Their structures were elucidated on the basis of spectroscopic studies. Compounds 1-8 were tested for their DPPH radical scavenging activity and, except compounds 2 and 5, other compounds showed scavenging activitv.

Antioxidant phenanthrenes and lignans from Dendrobium nobile

To study the antioxidant constituents from the stems of Dendrobium nobile, and to discuss theft structure-activity relationship. Compounds were isolated from a 60% ethanolic extract by various chromatographic techniques and were identified by spectral analysis. The antioxidant activities of compounds were evaluated by DPPH free radical scavenging assay. Five phenanthrenes and four lignans were obtained from the active fractions ofD. nobile. Their structures were identified as fimbriatone （1）, confusarin （2）, flavanthrinin （3）, 2,5-dihydroxy-4,9-dimethoxyphenanthrene （4）, 3,7-dihydroxy-2,4-dimethoxyphenanthrene （5）, syringaresinol （6）, pinoresinol （7）, medioresinol （8） and lirioresinol-A （9）, respectively. Compounds 2 and 6 exhibited more potent DPPH scavenging activities than vitamin C. All the above compounds were reported from this plant for the first time, and compounds 3, 4 and 9 were reported for the first time from the genus of Dendrobiurn. For all phenanthrenes and lignans, an electron-donating methoxyl group in the ortho position to the phenolic hydroxyl group exhibits enhanced antioxidant activities.

Identification and Evaluation of Antioxidant Activities of Bamboo Extracts

The antioxidant activity of solvent extracts from two main bamboo species, moso bamboo (Phyllostachys pubescens) and madake bamboo (P. bambusoides) in Japan, was first evaluated by scavenging free radical of 1,1-diphenyl-2-picrylhydrazyl (DPPH), the inhibition activity for peroxidation of linoleic acid, and the reduction power. The methanol-extracts of moso bamboo culms and madake bamboo leaves presented stronger antioxidant activity compared with DPPH scavenging activity. Methanol-extract of moso bamboo culms was further fractionated by different solvents and n-butanol soluble fraction exhibited the most significant activity in the DPPH scavenging assay. The fractionation of n-butanol soluble extract was isolated by silica gel column with gradient mixture solvent of chloroform and methanol. The isolated fractions were directed by the antioxidant activity measured by scavenging the stable DPPH free radical. It was observed that most of the eluted fractions showed the antioxidative activity. Fractions acquired from elution with the mixture solvent of chloroform and methanol (10:1–5:1) showed stronger antioxidant activity than the other fractions.

Antioxidant activity of polyaniline nanofibers

Well-confined uniform polyaniline （PANI） nanofibers were synthesized by using photo-assisted chemical oxidative polymer- ization of aniline in the presence of different dopant acids, and the radical scavenging ability of the produced PANI nanofibers was determined by the DPPH assay. It was found that the antioxidant activity of PANI nanofibers was higher than conventional PANI, and increased with decreasing of averaged diameter of the nanofibers. The enhanced antioxidant activity was concerned with increased surface area of PANI nanofibers.

Syntheses and Crystal Structures of [Na(H_2O)_(1/2)]X and NH_2(CH_2CH_3)_2X and Antioxidant Activity of the Former

In order to enhance the water-solubility and biological utilization rate of chrysin, sodium 5,7-dihydroxylflavone-8-sulfonate （1, [Na（H2O）1/2]X, X = C15H9OSO3, 5,7-dihydroxylfla- vone-8-sulfonate） was synthesized and its structure was identified on the basis of NMR, FT-IR and elemental analysis. The assembly of 5,7-dihydroxylflavone-8-sulfonate with diethylamide cation afforded diethylamide 5,7-dihydroxylflavone-8-sulfonate （2, NH2（CH2CH3）2X） which was characterized by FT-IR and elemental analysis. The crystal structures of 1 and 2 were determined by X-ray single-crystal diffraction analysis. The crystal of 1 is of triclinic system, space group P1, with a = 8.5628（13）, b = 12.8916（19）, c = 13.562（2） A, α = 82.494（1）, β = 78.601（2）, γ = 84.033（2）°, C30H20Na2O15S2, Z = 2, Mr = 730.59, V = 1450.3（4） A3, Dc = 1.673 g/cm3, F（000） = 748, p = 0.295 mm^-1, the final R = 0.0641 and wR = 0.1458. The crystal of 2 crystallizes in the triclinic system, space group Pi, with a = 7.689（2）, b = 11.184（3）, c = 11.734（3） A, α = 74.268（3）, βl = 81.751（4）, γ= 87.991（3）°, C19H21NO7S, Z = 2, Mr= 407.43, V= 961.2（4） A3, Dc = 1.408 g/cm3, F（000） = 428, p = 0.210 mm^-1, the final R = 0.0484 and wR = 0.1195. In 1, the three-dimensional structure is organized into organic and inorganic regions; the flavone skeletons are stacked into organic regions by π...π staeking interactions; inorganic regions are generated by Na-O coordination bonds among sulfonate groups, coordinated water molecules and NaI. The sulfonate groups play an important role as a bridge of inorganic and organic regions. One-dimensional chain structure of 2 is extended by N-H…O hydrogen bonds and π...π stacking interactions. Furthermore, the antioxidant activity of 1 was evaluated. The scavenging activity of 1 to DPPH free radical is better than that of the parent compound chrysin.

Identification and Biological Activities of the Phenolic Compounds in <i>Eisenia arborea</i>

Four polyphenols were isolated and purified from a brown alga Eisenia arborea. These phlorotannin compounds showed strong radical scavenging and some enzyme inhibitory activities. All of the compounds showed strong antioxidative, acetylcholinesterase and butyrylcholinesterase inhibitory, and tyrosinase inhbibitory activities at 100 μg/mL. Dieckol and PFF inhibited butyrylcholinesterase, a new target for the treatment of Alzheimer’s disease, very strongly even at 10 μg/mL, more strongly than AChE. These two compounds also effectively inhibited tyrosinase. These results support the potential of developing natural antioxidants and antidementia agents from the brown alga.

Effect of pH on Antioxidant and Phytochemical Activities of Mulhatti Roots (Glycyrrhiza glabra L.)

Glycyrrhiza glabra L.is the most widely used herb in the ancient history of Ayurvedic medicine,as a medicinal value as well as an aromatic herb,and it is commonly known as Mulhatti.Mulhatti roots are useful for medically and are also a good source of phytoproducts and secondary metabolites present in Mulhatti roots are triterpenoid saponin,glycosides,glycyrrhizin,prenylated biaurone,licoaagrone,7-acetoxy-2-methylisoflavone,4-methylcoumarin,liqcoumarin,glycyrrhetinic acid,quercetin,liquiritigenin,isoliquiritigenin,etc.This study was carried out to study the evaluation of phenolic compounds,2,2-diphenyl-1-picrylhydrazyl(DPPH)free radical activity and general antioxidant capacity of water extracts of Mulhatti roots prepared at different pH values,namely 2,4,7 and 9.Data have shown great differences in terms of results.Most of the phenolic compounds are at pH 7(19.25),followed by pH 9(17.25),pH 2(14.62)and pH 4(8.89 mg GAE/g),respectively.Similarly,the flavonoid data also showed variations,the maximum has been present in pH 2(5.39),then pH 7(3.02),pH 9(1.79)and pH 4(1.40 mg CE/g),respectively.The value for DPPH IC50 free radical scavenging activity was the lowest at pH 7(82.22),followed by pH 2(110.40),pH 4(111.99)and pH 9(146.24μg/mL)and IC50 reference standard(ascorbic acid)was 59.52μg/mL in distilled water.The total capacity of the antioxidant was the highest at pH 2(9.93)followed by pH 4(5.54),pH 7(5.34)and pH 9(4.23 mg AAE/g).According to current research,pH 7 is the best for phytochemicals as well as antioxidants that catch harmful radicals.

A Study on the Whitening Efficacy of Flavones in Lotus Leaf

Taking lotus flavones as the research object, cytotoxicity was evaluated by MTT test, inhibitory effects onthe activity of tyrosinase was studied, and DPPH scavenging experiments were carried out. Lotus flavoneswere used in a formula of skin cream and facial whitening effects were examined. Results shows that lotusflavones are exhibited no cytotoxicity at a concentration equal or less than 1%, and it can decrease the activityof tyrosinase at a concentration between 0.02%~0.30%. Lotus flavones can scavenge DPPH radical. The skincream containing lotus flavones declines facial melanin content. Lotus flavones have good biological safety andare suitable in cosmetics as whitening agents.

Comparison of Antioxidant Activities of Silver Nanoparticles and Methanol Extracts of Three Indigenous Nigeria Herbal Seeds

The antioxidant of seeds was carried out using extracts from methanol and Silver Nanoparticles from the spice. The SEM shows the shapes, dispersion and agglomeration of the sample, while the EDX confirms the SEM and the presence of some compounds. The FT-IR reveals the AgNPs capping and reducing the particular biomolecule from the functional group for identification. Compounds found in the FT-IR seeds of Capsicum annum are Ag L (Silver iodide), C K (Cyanogen chloride), P K (Phenol). Monodora myristica are Mo L (Molybdenum), Ag L (Silver iodide), C K (Cyanogen chloride), P K (Phenol), Mg K (Magnesium). Piper guineense are Ag L (Silver iodide), Ci K (Potassium chloride), C K (Cyanogen chloride), P K (Phenol). The seeds show that the AgNPS of CA and MM has a better antioxidant activity than the methanol of CA and MM, while the PG methanol has a better activity than the AgNPS PG. The control (Catechin and Galic acid) has a slight overall better DPPH activity than the AgNPS. It is important to note that there is a concentration dependency in CA, MM AgNPS, PG methanol respectively. Notably, at CA methanol, the conc. at 125 was higher than the conc. at 250. Hence, there is need to create a great part in using plant samples for making tabulated or capsulated drugs for treatment of diseases and using plant silver nanoparticles to develop a healthy food/drug preservative package material “smart packaging” that will enhance shelf-life.

Chemical composition and antioxidant activity of certain Morus species

In the present work,the fruits of four Morus species,namely Morus alba (white mulberry),Morus nigra (black mulberry),Morus laevigata (large white fruit),and Morus laevigata (large black fruit),were analyzed for proximate composition,essential minerals,and antioxidant potentials.For this purpose,the ripe fruits were collected from the northern regions of Pakistan.The major nutritional components moisture,ash,lipids,proteins,fibres,carbohydrates,and total sugar) were found to be in the suitable range along with good computed energy.Total dry weight,pH,and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g,(3.20±0.07)–(4.78±0.15),and (0.84±0.40)%–(2.00±0.08)%,respectively.Low riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits,while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW).The mulberry fruits were rich with regard to the total phenol and alkaloid contents,having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW,respectively.Sufficient quantities of essential macro-(K,Ca,Mg,and Na) and micro-(Fe,Zn,and Ni) elements were found in all the fruits.K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g,while Ca,Na,and Mg contents were (440±3.21)–(576±7.37),(260±3.86)–(280±3.50),and (240±3.51)–(360±4.20) mg/100 g,respectivly.The decreasing order of micro-minerals was Fe>Zn>Ni.The radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective fruits.Based on the results obtained,mulberry fruits were found to serve as a potential source of food diet and natural antioxidants.

Two Unusual Flavanol Derivatives from Brainea insignis

Two new flavanol derivatives, bearing phenylpropionic acid moiety at C-4 through a C--C bonding, named brainin B （1） and brainin C （2）, were isolated from Brainea insignis. Their structures were elucidated by NMR and MS spectrometry, Brainins B and C were tested for their antioxidant properties in DPPH （2,2-diphenyl-l-picryl- hydrazyl） radical scavenging, and both compounds displayed potent antioxidant activities.

Antioxidant and modulatory role of Chlorophytum borivilianum against arsenic induced testicular impairment

Arsenic has a suppressive influence on spermatogenesis and induces impairment in male reproductive system due to oxidative stress. The present study was aimed to test the arsenic induced toxicity and protection by Chlorophytum borivilianum. The effect of sodium arsenite （4 mg/（kg body weight （bw）.day）） via double distilled water without or with C. borivilianum （800 mg/（kg bw.day）） was evaluated in Swiss albino mice for 30 days. The radical scavenging activity of the aqueous C. borivilianum root extract was measured using DPPH （1,1-diphenyl-2-picryl hydrayzyl） radical. Qualitative assessment of various cell types in the testis, sperm count and motility, testicular activity of lipid peroxidation （LPO）, reduced glutathione （GSH）, acid and alkaline phosphatase, cholesterol and serum testosterone were monitored. Arsenic treatment showed a significant increase in LPO, acid and alkaline phosphatase, cholesterol and decrease in sperm count, sperm motility, GSH and serum testosterone. Combined treatment showed significant decrease in LPO, acid and alkaline phosphatase, cholesterol and elevation in sperm count, sperm motility, GSH and serum testosterone. Testicular histopathology showed that C. borivilianum had reduced degeneration of germ cell in the seminiferous tubules and loss of sperms induced by arsenic intoxication. The results thus led us to conclude that administration of C. borivilianum root extract is found to be protective against arsenic induced toxicity.