Evaluation of the Antioxidant and Antiradical Properties of Some Phyto and Mammalian Lignans

In this study, the antioxidant and antiradical properties of some phyto lignans (nordihydroguaiaretic acid, secoisolariciresinol, secoisolariciresinol diglycoside, and α-(-)-conidendrin) and mammalian lignans (enterodiol and enterolactone) were examined by different antioxidant assays. For this purpose, radical scavenging activities of phyto and mammalian lignans were realized by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) radical (ABTS•+) scavenging assay and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging assay. Additionally, the reducing ability of phyto and mammalian lignans were evaluated by cupric ions (Cu2+) reducing (CUPRAC) ability, and ferric ions (Fe3+) and [Fe3+-(TPTZ)2]3+ complex reducing (FRAP) abilities. Also, half maximal inhibitory concentration (IC50) values were determined and reported for DPPH• and ABTS•+ scavenging influences of all of the lignan molecules. The absorbances of the lignans were found in the range of 0.150–2.320 for Fe3+ reducing, in the range of 0.040–2.090 for Cu2+ reducing, and in the range of 0.360–1.810 for the FRAP assay. On the other hand, the IC50 values of phyto and mammalian lignans were determined in the ranges of 6.601–932.167 µg/mL for DPPH• scavenging and 13.007–27.829 µg/mL for ABTS•+ scavenging. In all of the used bioanalytical methods, phyto lignans, as secondary metabolites in plants, demonstrated considerably higher antioxidant activity compared to that of mammalian lignans. In addition, it was observed that enterodiol and enterolactone exhibited relatively weaker antioxidant activities when compared to phyto lignans or standard antioxidants, including butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), Trolox, and α-tocopherol.

ANTIOXIDANT ACTIVITY AND TOTAL PHENOLIC CONTENT IN RIPE AND UNRIPE POMEGRANATE (PUNICA GRANATUM L.) FRUIT JUICE

Objective: P. granatum L. is famous for antioxidant activity and utilized as a nourishing foodstuff. This work aimed to recognize the antioxidant activity and TPC in extracts of ripe and unripe fruit juice. Methods: Competency of the solvents (water, methanol, acetone, chloroform, ethanol) were evaluated by analyzing extracts of ripe and unripe P. granatum L. fruit juice for TPC and DPPH* scavenging assay. FTC method measured the level of peroxides. Results: In TPC extraction, the water solvent showed greater potential in both ripe (10.5±2.1) and unripe fruit juice (4.1±0.3) amongst all other solvents. Ethanol and water solvent showed the highest value of DPPH* scavenging activity (96%±6.81 and 72%±3.50 respectively) in ripe and unripe fruit juice. According to absorbance of DPPH radicals, the water solvent showed the highest antioxidant potential in ripe fruit juice (86%±6.78) like chloroform solvent in unripe fruit juice (14%±0.03). Unripe fruit juice showed lowest level of absorbance of DPPH radicals and highest antioxidant potential amid all solvents. In FTC method, unripe fruit juice showed the highest antioxidant activity and low amount of peroxides for consecutively seven days. Conclusion: Ripe fruit juice showed the highest TPC and unripe fruit juice showed the maximum value of antioxidant potential. P. granatum L. provides an excellent supply of antioxidant activity and used in pharmaceutical and food industry.

Composition and Radical Scavenging Activity of Essential Oil from Xylopia aethiopica: A New Chemotype Grown in Nigeria

Despite its use in traditional medicines, studies on the radical scavenging activity of the essential oils from Xylopia aethopica from Nigeria have not been widely reported in literature. Thus, in this work, fresh fruits of Xylopia aethopica were air dried, ground and extracted through hydro-distillation using Clevenger-type distillation apparatus. The essential oil was analyzed using Gas Chromatographic/Flame Ionization Detection (GC/FID) Technique and confirmed by gas chromatographic/mass spectrometric (GC/MS) analysis. The radical scavenging activity of the essential oil was evaluated in comparison with butylated hydroxylanisole (BHA) through 1,1-Diphenyl-2-picrylhydrazyl (DPPH) scavenging assay. A total of Forty-five compounds were detected through the GC/FID and GC/MS analyses of the essential oil of Xylopia aethopica. The major constituents of the essential oil were β-pinene (55.15%), α-thujene (9.23%) and α-eudesmol (8.61%) and α-pinene (6.77%). Other notable constituents were 1, 8-cineole (6.13%), ethyl cinnamate (5.83%) and elemol (5.17%). The methanolic solution of the essential oil showed concentration-dependent scavenging activity on 1,1-Diphenyl-2-Picrylhydrazyl (DPPH) radical. The results of the Scavenging effect of the Xylopia aethopica essential oil compared well with the activity of the commercial radical scavenging agent, Butylated hydroxylanisole (BHA) and this suggests possible uses of the essential oil as sources of natural antioxidants. Data were analyzed using R statistical software.

Antioxidant, Antimicrobial, and Molecular Docking Studies of Novel 1, 4-naphthoquinone Derivatives

The synthesis of novel 1,4-naphthoquinone derivatives has attracted prominent interest in the field of medicinal chemistry since these compounds exhibit potent pharmacological activity as antibacterial, antioxidant, antifungal, and anticancer. Herein, a series of novel 1,4-naphthoquinone derivatives 4-7, 8a-c, and 9a-d containing heterocyclic moieties were synthesized in good yields and characterized by spectral and elemental analyses. All the new synthesized compounds were subjected to in-vitro antimicrobial testing against gram-positive, gram-negative, and fungal strains by calculating the average of the zone of inhibition. The antimicrobial results showed that compounds 8b, 9b, and 9c displayed the highest efficacy against both bacterial and fungal strains. Further studies have been conducted to estimate the antioxidant activity of the compounds using DPPH scavenging assay. The obtained results revealed that compounds 9d, 9a, 9b, 8c, and 6 exhibited the highest radical scavenging activity. Docking studies of the most active antimicrobial compounds within GLN- 6-P, recorded good scores with several binding interactions with the active site.

Comprehensive GC-MS and FT-IR Profiling of Coleus zeylanicus essential oil and investigation of its anti-fungal and anti - oxidant activities

To evaluate the leaf volatile constituents of essential oil of Coleus zeylanicus and evaluate their anti-oxidant and anti-fungal activity. The Chemical composition of Coleus zeylanicus essential oil was determined using GC-MS and FT-IR analytical techniques. The antioxidant activity was evaluated using DPPH scavenging assay. The anti-fungal effect was tested against two potential pathogenic fungal strains - Candida albicans and Malassezia furfur using agar well diffusion method. The essential oil was profiled by the presence of sesquiterpene hydrocarbons 90.67% of their total composition followed by oxygenated monoterpenes and monoterpene hydrocarbons as 5.3% and 2.1% respectively. The GC-MS results showed 14 compounds from Coleus zeylanicus leaf EO representing 98.07% of the total oil composition. The major component was identified as a-Gurjunene (35.94%), a-bisabolol (10.82%) and G-selinene (4.26%). EO showed remarkable antioxidant activity values of IC50 = 59.78± 3.21µg/ml by DPPH scavenging assay. The essential oil showed interesting anti-fungal effects against two pathogenic fungal strains. The most sensible strains to Coleus zeylanicus EO was Malassezia furfur (32.00±0.50mm) compared to that of Candida albicans (15.00±1.25mm). Hence, Coleus zeylanicus EO has potential application against fungal infection and oxidative stress-related diseases. However, further investigations are necessary to isolate and investigate the action mechanism of these bioactive compounds.

PHYTOCHEMICAL ANALYSIS, ANTIMICROBIAL AND ANTIOXIDANT ACTIVITIES OF THYMUS VULGARIS L.

Medicinal activities of Thymus vulgaris L. were studied in the underlying research which was conducted in University of Central Punjab, Lahore. The powdered plant sample was collected and subjected to extraction and filtration by dissolving it in seven different solvents and thus the fractions obtained, were used for further analysis. The qualitative and quantitative analysis was carried out which revealed that this plant contained many biologically active compounds like saponin, alkaloids etc. These compounds have enormous bioactive roles. Antimicrobial activity was also determined in which four bacterial strains were used and the susceptibility of all the fractions of plant extract was determined by their inhibition zones which were calculated in mm. The results showed that water and chloroform extracts of plant has highest activity. The antioxidant activity was also determined by DPPH scavenging assay for which different concentrations of all plant extracts were made and their absorbance was noted to measure the percentage inhibition of each concentration, which revealed that this plant has significant antioxidant activity. The results have been represented using statistical approach that revealed that T. vulgaris plant has significant antibacterial and anti-oxidant activities and phytochemical analysis also proved that it has many useful compounds which have voluminous biological activity and these could be used in the formation of novel drugs.

Valorization of European Cranberry Bush (Viburnum opulus L.) Berry Pomace Extracts Isolated with Pressurized Ethanol and Water by Assessing Their Phytochemical Composition, Antioxidant, and Antiproliferative Activities

Defatted by supercritical CO2, Viburnum opulus berry pomace (VOP) was subjected to consecutive extraction with pressurized ethanol (E) and water (W) and yielded 23% of VOP-E and 8% of VOP-W, respectively. The major phytochemical groups covering 42 identified and quantified constituents in VOP extracts were organic and phenolic acids, iridoids, quercetin and (epi)catechin derivatives, flavalignans, procyanidins, and anthocyanins. The on-line HPLC-DPPH•-scavenging assay revealed the presence of numerous antioxidants. VOP-E had a higher total phenolic content, was a stronger antioxidant (equivalent to 0.77, 0.42, and 0.17 g trolox/g in oxygen radical absorbance capacity (ORAC), ABTS, and DPPH assays, respectively), and recovered the major part of phenolics from the pomace; however, both extracts demonstrated similar antioxidant activity in the cellular assay. VOP-E inhibited HT29 cancer cells at non-cytotoxic concentrations. The results of this study revealed that VOP contains valuable phytochemicals possessing antioxidant and antiproliferative activities. Consequently, extracts from VOP substances may be of interest in developing functional ingredients for healthy foods, nutraceuticals, and cosmeceuticals.

Antioxidant, Anti-inflammatory, Cytotoxic and Analgesic Activities of Sensevieria trifasciata

Sansevieria trifasciata is a common perennial ornamental plant which freely grows and widely found in homes, parks, and woodlands. Traditionally, this plant has been used against acne, allergy, helminths and fungal infections. In the present study, the ethanolic extract of leaves of Sansevieria trifasciata (STET) has been used to study the phytoconstituents and several bioactivities. In vitro antioxidant activity of STET has been determined by DPPH scavenging assay and measuring the total tannins and phenolic contents. Anti-inflammatory activity has been evaluated by hypotonic solution and heat induced hemolysis. Moreover, cytotoxic and analgesic activities have also been evaluated by brine shrimp lethality assay and acetic acid induced writhing inhibition method, respectively. STET confirmed the presence of reducing sugar, combined reducing sugar, tannins, flavonoids, glycosides, proteins and steroids. In DPPH scavenging assay, STET revealed the IC50 value 2.19 μg/ml whereas the standard showed 1.39 μg/ml. In addition, the total tannins and total phenolic contents were found to be 10.78 mg and 31.99 mg GAE/g of dried plant extract, respectively. In hypotonic solution induced hemolysis test, the plant extract exhibited 39.27, 37.04 and 33.19 % inhibition at 0.5, 1.0 and 2.0 mg/ml concentration where the reference standard displayed 30.57 % inhibition. In heat-induced hemolysis, the STET also displayed 34.25 % inhibition of hemolysis at 1 mg/ml. Furthermore, in analgesic and cytotoxic activity tests, STET showed potential activities in a dose dependent manner. The results of the present studies suggest that STET has antioxidant, anti-inflammatory, cytotoxic and analgesic activities. Bangladesh Pharmaceutical Journal 23(2): 195-200, 2020

Bioactivities of Aeschynomene aspera (Fabaceae) Leaf Extract

Aeschynomene aspera (Family- Fabaceae), a traditionally used medicinal plant, is aquatic, perennial, erect subshrub up to 200 cm tall with compound leaves and locally it is called Shola (Bangladesh), Laugaun (India). The study started with phytochemical screening of ethanolic leaf extract of A. aspera followed by bioactivity study such as in-vitro antioxidant activity by free radical (DPPH) scavenging assay, estimation of total phenolic as well as total flavonoid contents and the analgesic, antidiarrheal and anthelmintic activities. Analgesic, antidiarrheal and anthelmintic activities were evaluated by acetic acid induced writhing inhibition in mice, castor oil induced diarrheal episode in mice and using living parasites Haemonchus contortus, respectively. The presence of carbohydrate, reducing sugar, glycosides, tannins, alkaloids, steroids, gums and flavonoids was estimated with the help of phytochemical screening. In DPPH scavenging assay the extract showed IC50 value of 86.14μg/mL where ascorbic acid showed 12.02μg/mL. It also exhibited total phenolic and flavonoid contents as 461.09 GAE/100g and 297.20mg Quercetin/100g of dried plant extract. About 36% and 61% writhing inhibitions were observed in mice at 250 and 500mg/kg doses of A. aspera leaf extract, respectively. Anthelmintic activity showed by the extract was dose dependent. The extract also showed 46.01 and 71.68% inhibition of defecation in mice at doses 250 and 500 mg/kg, respectively. All these suggest that the A. aspera extract possesses antioxidant, analgesic, anthelmintic and antidiarrheal activities. Bangladesh Pharmaceutical Journal 23(2): 109-116, 2020

Chemical Constituents of Luculia pinceana in Vietnam and Evaluation of their Biological Activity

Background: In the flora of China and Vietnam, Luculia pinceana Hook of the family Rubiaceae is described as a medicinal plant. Prior chemical studies of L. pinceana in China isolated iridois, glycosides of cincholic acid, and kaempferol glycosides from the stem, however, have not been conducted with L. pinceana in Vietnam. Methods: The stem of L. pinceana was extracted with a mixture of 90%EtOH–H2O at room temperature and the extract was further fractionated by using liquid-liquid extraction and repeated column- chromatographic techniques. Spectroscopic data (IR, MS, 1D- and 2D-NMR) were used to determine structures of isolated compounds. Results: Thirteen compounds were isolated and structurally determined. Oleanolic acid (2), scopoletin (3), cleomiscosin A (4), (E)-mappianine E (5a), (Z)-mappianine E (5b), vanillic acid (6), 2-hydroxyacetophenone-4-O-β-D-glucopyranoside (7), sweroside (10), and 4-methoxyacetophenone- 2-O-β-D-glucopyranoside (11) were isolated for the first time from L. pinceana. Compounds 6, 10, 11, loganin (8), 7-ketologanin (9) were not active (IC50 > 300 µg/ml), whereas 7 showed a weak activity (IC50 268.35 µg/ml) in the DPPH (1,1-diphenylpicrazyl) radical scavenging assay. A mixture of 5a/5b was cytotoxic against the human cancer cell line HepG2 (IC50 100.57 µg/ml) in the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Conclusion: L. pinceana in Vietnam was investigated for the first time. We isolated compounds of varied biosynthetic origins including monoterpene indole, iridoid, coumarin, coumaro-lignoid, phytosterol, oleanane triterpenoid, phenolic acid, and acetophenone. Nine of the thirteen compounds are newly isolated from L. pinceana. The study determined weak scavenging activity of acetophenone (7) in the DPPH-scavenging assay and weak cytotoxicity of a mixture of two monoterpene indoles (5a and 5b) against HepG2 cell.