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.

Comparison of Antioxidant and Antimicrobial Activities of Acetone and Water Extracts of <i>Theobroma cacao</i>Beans

This present study compared antioxidant and antimicrobial activities of acetone and water extracts of Theobroma cacao beans against Escherichia coli. Total phenolic content (TPC) in both extracts was estimated by the Folin-Denis reagent. The present study showed that the 70% (v/v) acetone extract had a higher extraction yield and TPC (37% and 109 mg TAE g-1 dry weight) than the water extract (33% and 76 mg TAE g-1 dry weight). The antioxidant activities of both extracts were estimated by the DPPH Scavenging Assay. The extract obtained using 70% (v/v) acetone showed higher antioxidant activity (54%) compared to the antioxidant activity obtained using water (34%). Antimicrobial activities of acetone and water extracts from Theobroma cacao were measured against Escherichia coli and were screened by agar well diffusion method and further confirmed with the disc diffusion method. The bacterial growth was measured in Mueller Hinton agar. The extracts inhibited the growth of the Escherichia coli cultured, and the acetone extracts showed antimicrobial capacity comparable or equivalent, as seen in commercial ampicillin.

Improvement in Oxidative Stability of Soybean Oil by Mango Kernel Extracts

This work was undertaken to explore the potential of fruit waste materials as sources of natural antioxidants. Kernels of four varieties of mangoes of Indian origin were studied. Kernels were extracted with five different solvents, tested for extraction efficiency and total phenolic content （TPC）. As the methanol proved to be the best solvent, it was used for further analysis. The methanolic extracts of kernels had reducing power （RP） and scavenged 2, 2 diphenyl-l-picryl hydrazyl （DPPH） radical, which is related to their antioxidant activity （AA）. When analyzed in HPLC, the extracts showed the presence of phenolic compounds. The extracts had the higher capacity to reduce the formation of peroxides and slow down the rate of oxidation than butylated hydroxyl toluene （BHT） in refined, bleached deodorized soybean oil （RBD SBO）. Based on the results obtained mango kernels are potential source of natural antioxidants owing to their antioxidant activity.

Edible Ectomycorrhizal Mushrooms Russula spp. of Côte d’Ivoire: Total Phenolic Content, HPLC-Profiles of Phenolic Compounds and Organic Acids, Antioxidant Activities

The aim of this study was to investigate the phenolic compounds content, HPLC-profiles of phenolic compounds and organic acids, and also antioxidant activities via the ability to scavenge DPPH radical of three wild edible mushrooms belonging to Russula genus and being collected in center of Côte d’Ivoire. Total phenolic compounds, flavonoids and tannins contents of methanolic extracts were assessed by colorimetric assays. So, the obtained values of these chemical parameters ranged from 394.05 to 513.50 mg/100 g DW, 94.50 to 139.95 mg/100 g DW and from 124.20 to 165 ± 0.54 mg/100 g DW, respectively. Otherwise, HPLC-profiles of the methanolic extracts revealed that quercetin, salicylic acid and tannin ol were the main phenolic compounds in R. delica whereas R. lepida contained gallic acid, catechin and protocatechuic acid as main phenolic compounds. Besides, it showed that the phenolic compounds such as salicylic acid, tannin ol and catechin were observed in R. mustelina. As for HPLC-profiles of organic acid, the fumaric and malic acid were recorded as the main organic acids in the three species of wild edible mushrooms. However, citric acid content was found to be highest in R. lepida. The methanolic extracts of the three mushrooms exhibited high DPPH radical scavenging activities ranging from 74.92% to 58.92%. These wild edible mushrooms could be considered a potential supply source of adequate natural antioxidant for local population.

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.

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.

A new flavonol C-glycoside and a rare bioactive lignanamide from Piper wallichii Miq. Hand.-Mazz

This study was conducted to investigate the chemical constituents of Piper wallichii （Miq.） Hand.-Mazz. and evaluate their biological activity. Compounds were isolated by various column chromatographic methods, and their structures were elucidated on the basis of physical characteristics and spectral data. The 1, 1-diphenyl-2-picrylhydrazyl （DPPH）-scavenging activity and acetylcholinesterase （AChE）-inhibitory activity of the compounds were evaluated. Five compounds were obtained and identified as 8-C-β-D-glucopyranosylkaempferol-3-O-β-D-glucopyranoside （1）, 1, 2-dihydro-6,8-dimethoxy-7-hydroxy-l-（3, 5-dimethoxy-4-hydroxyphenyl）-N^1, N^2-bis-[2-（4-hydroxyphenyl）ethyl]-2, 3-naphthalene dicarboxamide （2）, goniothalactam （3）, aristololactam A IIla （4） and piperlonguminine （5）. Compound 1 was a new flavonol C-glycoside, 2 was a rare lignanamide, which was isolated from the family Piperaceae for the first time, and compound 3 was isolated from this plant for the first time. Among them, 2 showed potent DPPH-scavenging activity, with IC50 of 31.38 ± 0.97 μmol·L^-1; Compounds 2, 3, and 4 showed AChE inhibitory activity at 100 μmol·L^-1, with inhibition rates of 28.57% ± 1.47%, 18.48% ± 2.41% and 17.4% ±3.03%, respectively.

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.