DPPH Scavenging Effect Research Articles

Ameliorative Effect of Bouea macrophylla Griffth Seed Extract Against Bacteria-Induced Acne Inflammation: in vitro study.

Currently, bioactive compounds derived from nature have been thought to be promising anti-acne substances owing to the variety of potential biological effects. This study aimed to evaluate the ameliorative effect of Bouea macrophylla Griffth seed extract against bacteria-induced acne inflammation for the first time in terms of antibacterial effects against acne-inducing bacteria, anti-inflammatory, and antioxidant properties. Initially, extracting procedures were optimized and five different extracts were obtained. Considering their antibacterial activities against Cutibacterium acnes, Staphylococcus aureus, and Staphylococcus epidermidis, ethanolic and ethyl acetate fractions exerted a notable effect which were highly superior above those of polyphenol standards. Additionally, these two extracts presented outstanding antioxidant capacities in terms of DPPH and ABTS radicals scavenging effects, reducing power, and inhibitory effect on lipid peroxidation which also play a role in the exacerbation of acne inflammation. Besides, inhibition on lipid peroxidation and reducing power of ethanolic fraction were significantly (p<0.05) better than those of ethyl acetate fraction which was corresponding to their phenolic and ellagic acid contents. However, flavonoids found in ethyl acetate fraction might play an important role in its potentials. After that, the anti-inflammatory effects of the extracts were elucidated by means of inhibition on nitric oxide production from LPS-induced RAW 264.7 cell lines at which the effects of both extracts were dosedependency. Taken together, our findings have apparently proven that B. macrophylla seed extracts exerted a variety of potential properties including antioxidation, anti-acne-inducing bacteria, and anti-inflammatory effects which could serve as a promising anti-acne agent for cosmeceutical applications.

HPLC-DAD phenolic screening and in vitro assessment of antimicrobial, antioxidant and anti-inflammatory activities of Tanteboucht dates.

The date palm (Phoenix dactylifera L.) is one of the most important crops in arid and semi-arid zones. Date fruit occupies a good place in traditional medicine among the Saharan residents, due to its therapeutic virtues; although there may be several therapeutic virtues yet to be discovered. The aim of this study was to investigate the phytochemical and pharmacological properties of the hexanic (EHx), chloroformic (ECh), ethyl acetate (EAc) and aqueous (EAq) extracts of Tanteboucht pulp. The phytochemical characterization and estimation of phenolic compounds were done based on an HPLC-DAD approach. The antioxidant activity was evaluated by a DPPH scavenging effect test. The sensitivity of 7 bacterial strains and Candida albicans to Tanteboucht extracts was tested using the diffusion disc on agar medium method. The membrane stabilization test was used to determine the in vitro anti-inflammatory effect of the fruit extracts. Fourteen phenolic compounds were detected in organic extracts and EAc was the richest followed by ECh and finally EHx which was very poor in these molecules. All extracts showed antioxidant, anti-inflammatory and antimicrobial properties which differ in rate. Indeed, ECh had the greatest scavenging effect on DPPH, followed by EAc and then EAq. EAc was the most potent inhibitor of microbial strains. EAc and ECh were more efficient at membrane stabilization followed by EAq and the three extracts had more anti-inflammatory capacity than the positive control acetyl salicylic acid. The obtained considerable activities were significantly correlated with flavonoid and tannin contents in the extracts.

Antioxidant Activity and the Potential Mechanism of the Fruit From Ailanthus altissima Swingle.

The fruits of Ailanthus altissima Swingle (AS) possess a variety of pharmacological activities. Its antioxidant activity and the potential mode of action have not yet been investigated. In in vitro studies, AS revealed the strong reducing power and DPPH scavenging effect, but hydroxyl radical scavenging activity and ferrous ions-chelating ability were not strong. Meanwhile, the oxidative stress RAW264.7 cell injury model was established, the low and medium-doses of AS showed significant protective effects on the viability of H2O2-treated cells by CCK-8 method. Besides, three doses of AS all increased the activities of SOD, CAT, and GSH-Px and decreased the MDA level compared with the H2O2 group, suggesting it significantly relieved oxidative stress of cells. The active ingredients and related targets of AS were collected by HERB and Swiss Target Prediction database, the common targets of drugs and diseases database were conducted by GeneCards database platform and the Venny platform. We screened the core targets of AS like threonine kinase1 (AKT1), mitogen-activated protein kinase 1 (MAPK1), sirtuin-1 (SIRT1), mechanistic target of rapamycin kinase (MTOR) by STRING database, and the key pathways involved PI3K-AKT and FoxO signaling pathway by KEGG pathway enrichment analysis. Besides, qRT-PCR revealed AS preconditioning significantly up-regulated the expression level of AKT1, SIRT1, MAPK1, and MTOR in model cells, and the effect was related to the regulation of FoxO and PI3K/AKT signaling pathway. In summary, AS showed significant antioxidant activity and its potential mechanism was regulating FoxO and PI3K/AKT signaling pathway.

Comparative free radical scavenging and hypoglycemic activities of n-hexane, ethyl-acetate, and aqueous fractions of Azanza garckeana pulp

Background: The prevalence of diabetes mellitus is increasing on a global trend. The aim of the present study is to identify the most effective antioxidants and hypoglycemic fraction of Azanza garckeana. Methods: The fractions (nhexane or ethyl-acetate or aqueous) of A. garckeana were administered to the alloxan-induced diabetic rats at doses of 100, 200, and 400 mg/kg for 15 days. Antioxidants activities were evaluated at concentrations of 62.5, 125, 250, and 500 µg/mL using the DPPH scavenging assay. Results: Results revealed that both the hexane, ethyl-acetate, and aqueous fractions exhibited hypoglycemic and antioxidants activities in a dose-dependent manner. The n-hexane fraction demonstrated highest percentage DPPH scavenging effect of 26.34±3.43, 38.44±4.35, 59.34±3.45, and 74.83±5.35 at 62.5, 125, 250, and 500 µg/mL respectively. The ethyl-acetate fraction demonstrated 19.33±2.98, 28.94±3.24, 47.34±2.90, and 57.82±4.54 respectively while the aqueous fraction exhibited the least activities of 12.45±23.45, 18.64±2.94, 27.94±3.89, and 39.43±3.89 at concentrations of 62.5, 125, 250, and 500 µg/mL respectively. In addition, the n-hexane fraction demonstrated the most significant hypoglycemic effect with the highest glucose reduction of 58.97 ±3.45 %, 63.86±5.35 %, and 66.51±4.35 %, ethyl acetate fraction demonstrated glucose reduction of 7.55±0.54%, 21.77±2.35 %, and 29.56±3.46 % while the aqueous fraction demonstrated the least hypoglycemic effect of 9.89±2.67 %, 18.09±3.45 %, and 18.87±3.24 at 100, 200 and 400 mg/kg bw respectively. Conclusion: The n-hexane fraction of Azanza garckeana extract could serve as a reservoir of bioactive agents that could be useful for the development of a new anti-diabetic agent

Antioxidant activity and polyphenol composition of Pistacia terebinthus fruit from Tessala (Western Algeria)

Background: Consumption of traditional herbal beverages has been generally increased in the last decades, Terebinth coffee, known as ‘‘menengic coffee’’ in Turkish, is one of the most consumed herbal coffees in Turkey, turpentine tree is one of the components of the Mediterranean bush, particularly in Algeria, known as Betoum el Kiffan is largely used as food and in traditional medicine. Aims: In this study, Total phenol, flavonoid content, and antioxidant activity of three extracts of Pistacia trebinthus fruit growing in Algeria was measured using radical scavenging activity tests and metal-related tests including, ferric-reducing antioxidant power (FRAP). The chemical composition profile of the fruits and the coffee brands was identified by thin-layer chromatography, the effects of roasting method of this fruit was rivaled also. Materials and Methods: The total phenolic content of the extracts was determined using the Folin-Ciocalteu method. All extracts of the terebinth fruits and coffee brands displayed a high DPPH scavenging effect. Results: The results of the ferric-reducing antioxidant power show that the reduction capacity is proportional to the increase in the concentration of the samples. All the extracts of the plant exhibit antioxidant activities lower than those of the reference product besides the infusion extract of the P. terebinthus roasted coffee, which is the most active with an optical density of 1.68 nm at a concentration of 400 μg/mL. The chromatography results show that the various extracts of Pistacia terebinthus fruit carry a large number of polyphenols, in particular the carboxylic acids phenols. Conclusions: The plant can be considered as a coffee substitute and opens up promising avenues for the food and pharmaceutical industry in Algeria. Keywords: Antioxidant, Pistacia terebinthus, Coffee, FRAP, polyphenol.

In Vitro α-Amylase and α-Glucosidase Inhibitory and Antioxidant Activities of the Crude Extract and Solvent Fractions of Hagenia abyssinica Leaves.

Background The leaves of Hagenia abyssinica have been used in the management of diabetes mellitus in Ethiopian folk medicine. Thus, this study is aimed at investigating the in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the crude extract and solvent fractions of H. abyssinica leaves. Methods The in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities of the plant extract were assessed using 3,5-dinitrosalicylic acid (DNSA), p-nitro-phenyl-a-D glucopyranoside (p-NPG), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assays, respectively. Each value of percent inhibition of α-amylase, α-glucosidase, and DPPH scavenging effect was presented as means ± SEM (n = 3). Results The α-amylase inhibitory activity of the crude extract and solvent fractions was found to be concentration-dependent. The strongest activity was exhibited by the crude extract at the highest concentration with a percentage inhibition of 74.52% (IC50, 14.52 μg/ml) followed by water fraction 68.24% (IC50, 16.31 μg/ml), ethyl acetate fraction 61.57% (IC50, 18.73 μg/ml), and chloroform fraction 56.87% (IC50, 21.57 μg/ml) of H. abyssinica leaves. In the α-glucosidase inhibition assay, the maximum activity was exhibited by the aqueous fraction 62.54% (IC50, 11.67 μg/ml) followed by ethyl acetate fraction 54.97% (IC50, 15.89 μg/ml), crude extract 46.79% (IC50, >16.5 μg/ml), and chloroform fraction 36.44% (IC50, >16.5 μg/ml). In the antioxidant assay, the crude extract exhibited the highest antioxidant activity 86.36% (IC50, 10.25 μg/ml) followed by water fraction 78.59% (IC50, 13.86 μg/ml), ethyl acetate fraction 71.58% (IC50, 16.34 μg/ml), and chloroform fraction 63.65% (IC50, 18.83 μg/ml). Conclusion This study has revealed that H. abyssinica leaves possess noticeable in vitro α-amylase and α-glucosidase inhibitory and antioxidant activities.

In vitro antiplasmodial, cytotoxic and antioxidant effects, and phytochemical constituents of eleven plants used in the traditional treatment of malaria in Akwa Ibom State, Nigeria

Purpose: To evaluate the antiplasmodial effects of eleven plants (Bombax buonopozense, Carica papaya, Anthocleista djalonensis, Milicia excelsa, Heterotis rotundifolia, Homalim letestui, Starchystarpheta cayennnensis, Ocimum gratissimum, Cleistopholis patens, Chromolaena odorata and Hippocratea africana) reportedly used in the treatment of malaria in Akwa Ibom State of Nigeria.&#x0D; Methods: Phytochemical analysis was done by standard methods, while in vitro antiplasmodial evaluation was carried out using Plasmodium falciparum chloroquine-sensitive and chloroquineresistant strains using lactate dehydrogenase (pLDH) assay. Cytotoxicity test was undertaken by MTT assay on LLC-MK2 cells and the concentration killing 50 % of the cells (CC50) was calculated.Antioxidant activity of the ethanol extract was evaluated by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay.&#x0D; Results: Milicia excelsa, Heterotis rotundifolia and Chromolaena odorata had moderate antiplasmodial activity. Ocimum gratissimum and Hippocratea africana were weakly active. Milicia excelsa showed a considerable level of cytotoxicity, while Bombax buonopozense exhibited moderate cytotoxicity. Bombax buonopozense (95.3 %) and Ocimum gratissimum (92.0 %) exhibited high DPPH scavengingeffect comparable to Vitamin C (98.7 %). There was a significant correlation (p &lt; 0.05) between DPPH inhibition and the total phenolic contents of the eleven plants studied (r2 = 0.6616), between DPPH inhibition and flavonoids (r2 = 0.3553), between antiplasmodial activity and saponin content (r2= 0.3992), and between the two antiplasmodial evaluation assay methods (r2 = 0.614).Conclusion: The results of this work provide some justification for the use of Milicia excelsa, Heterotis rotundifolia, Chromolaena odorata, Ocimum gratissimum and Hippocratea africana in the treatment of malaria.&#x0D; Keywords: Antiplasmodial, Antioxidant, Cytotoxicity, Phytochemicals, Antimalaria

Preparation and characterization of antioxidant flavonoid-enriched extract from saffron by-product: a combination of ultrasound-assisted extraction and macroporous resin purification

The stigma of saffron, a precious spice widely used in the world, takes only 7.4% (w/w) of the total weight of the flower, resulting in wasting the rest 92.6% of the flower. The utilization of the waste saffron floral bio-residues (SFB) has hence attracted people’s attention. In this paper, ultrasound-assisted extraction (UAE) associated with macroporous resin (MPR) purification step was successfully applied to enrich antioxidant flavonoid in SFB extract for the first time, resulting in significant increase in flavonoid content compared with other extraction method reported in literatures. The yield of the extract was up to 10%, and the content of kaempferol-3-O-sophoroside (KS) in the obtained extract was more than 50%, which was much higher than the total flavonoid content (2.05–19.2%) reported in other literatures. UAE procedure was optimized by studying the influence of parameters, e.g., extracting solvent, time, temperature and sample–solvent ratio, based on contents of KS and delphinidin-3,5-di-O-glucoside (DG) and the antioxidant activity of the extract. Further enrichment of flavonoid was achieved by D-101 MPR with optimum purification conditions. Furthermore, 52 flavonoids, 8 alkaloids and 10 polyols were identified or putatively characterized from the SFB extract using UPLC-MS, and the contents of KS and DG were determined to be 501.90 and 22.01 mg/g, respectively. Besides, the SFB flavonoid extract showed good antioxidant activities with IC50 33.79 μg/mL for DPPH scavenging effect and 39.65 μmol/mg trolox for ORAC values

Determination of thermal, molecular changes, and functional properties in stabilized rice bran

Abstract In this study, stabilization was performed using three different oven temperatures (110, (T1) 130 (T2) and 150 °C(T3)) in the oven set at 10% moisture. The effect of stabilization on lipase activity, functional, and thermal properties of rice bran. Lipase activity of control (27.92 U/g) was to be higher than stabilized rice bran samples. Starch gelatinization peak temperature ranged from 70.05 (T3) to 85.09 °C (control). DPPH scavenging effect of control was 12.99 mmol TE. The highest DPPH radical scavenging effect value (15.72 mmol TE) was determined in the T3 sample. ABTS radical scavenging effect of stabilized samples significantly increased (p &lt; 0.05) and the increase for T1, T2, and T3 was found to be 73, 75, and 77%, respectively. The highest ferulic (4284 μg/g) and p-coumaric acid (1180 μg/g) contents were determined in T3 and T1 samples, respectively. The content of bound ferulic and p-coumaric acids of stabilized rice bran samples was 2.41 and 2.33 times higher than control samples. While prolamine content was 3.38–4.18 mg/mL; glutelin content ranged from 4.45 to 5.11 mg/mL. An obvious state change during stabilization was observed in all samples around 70–85.9 °C. The results of the study revealed that stabilization might change the functional and thermal properties of rice bran.

In vitro bactericidal, antidiabetic, cytotoxic, anticoagulant, and hemolytic effect of green-synthesized silver nanoparticles using Allium sativum clove extract incubated at various temperatures

AbstractThe current research aimed to evaluatein vitrobiological activities of green-synthesized silver nanoparticles using theAllium sativumclove extract. The stability of green-synthesized silver nanoparticles was evaluated via storage at 4°C, room temperature (37°C), and calcined at 300°C, 500°C, and 700°C. The antibacterial effect was evaluated using agar well, spread plate, biofilm reduction, and cell proliferation inhibition assays. The cytotoxic and antidiabetic effects were determined via brine shrimp lethality, protein kinase inhibition, and α-amylase inhibition assays. DPPH scavenging, iron-chelating, anticoagulant, and hemolytic effects were evaluated. The highest inhibition ofKlebsiella pneumoniaewas observed when freshly prepared, calcined (300°C), and stored nanoparticles (4°C and 37°C) were applied (9.66, 9.55, 7.33, and 6.65 mm) against freshly prepared and calcined at 700°C which showed the highest inhibition ofPseudomonas aeruginosa(8.55 and 7.66 mm). Cell viability assay, biofilm reduction assay, and spread plate method showed a significant antibacterial effect of freshly prepared silver nanoparticles. Freshly prepared and calcined nanoparticles at 300°C and 500°C possessed strong antioxidant and iron-chelating activity. Among all the synthesized silver nanoparticles, freshly prepared and calcined nanoparticles (300°C and 500°C) increases the prothrombin time. Silver nanoparticles possessed significant anticoagulant properties and less toxic at least concentration toward human RBCs. In brine shrimp lethality assay, freshly prepared nanoparticles showed a stronger toxic effect and caused high mortality of larvae. Protein kinase inhibition assay revealed that freshly prepared nanoparticles had the highest zone of inhibition (18.0 mm) at 50 µg/disc. Green-synthesized nanoparticles would be used as potential therapeutic agents to overcome both infectious and noninfectious diseases.

Antioxidant Activities Of Threadfin Bream (Nemipterus Japonicus) Hydrolysate And Its Effect On Oxidative Stability Of Frying Oil

The antioxidant activities and oxidative stability of palm olein frying oil added with threadfin bream (TFB) hydrolysate and Nanox 189 were studied. The DPPH radical scavenging activities and chelating effects of ferrous ion were evaluated and compared with α-tocopherol. Oxidative stability after 30 frying cycles were analysed for induction period, free fatty acids (FFA), peroxide values (PV), total polar compounds (TPC) and viscosity. Palm olein without any antioxidant were used as control. Nanox 189 exhibited higher percentage on DPPH scavenging effect and ferrous ion chelating effect than TFB hydrolysate. Frying oil added with Nanox 189 recorded the longest induction period which was up to 11 hr. while TFB hydrolysate added oil showed induction period of 9 hr. Nanox 189 addition in frying oil yielded the lowest FFA and PV followed by those added with TFB hydrolysate. Highest readings of TPC was recorded for TFB hydrolysate added oil which is 13%. Throughout the 30 frying cycles, the addition of TFB hydrolysate recorded lower percentage increase for viscosity than Nanox 189 with 4.7% compared to the latter which is 9.6%. Even though the antioxidant activities of TFB hydrolysate was lower than that of Nanox 189, the study suggested some antioxidant potential of TFB hydrolysate based on the DPPH radical scavenging activities and chelating effects of ferrous ion as well as its ability to slightly improve the oxidative stability of palm olein during the 30 frying cycles.

Rapid identification and quantification of bioactive metabolites in processed Camellia sinensis samples by UHPLC-ESI-MS/MS and evaluation of their antioxidant activity

Tea beverages have been enjoyed globally for the last several decades. The present study focuses on the comprehensive chemical and biological analysis of three processed tea products. A total of sixty-three compounds in processed samples were identified based on their exact masses and fragmentation patterns using LC-ESI-QTOF-MS/MS. Furthermore, quantification of eight analytes including caffeine (1), theophylline (2), (+)-catechin (3), (-)-epicatechin (4), (-)-epicatechin gallate (5), (-)-gallocatechin (6), (-)-epigallocatechin gallate (7) and quercetin-3-d-β-glucoside (8) in tea samples was performed using LC-ESI-IT-MS/MS. The concentrations of analytes were found in the range of 0.03mg/g to 75.58mg/g in all tea samples. The developed method showed excellent accuracy as %bias ranged from 0.2–3.69% and a good precision with %RSD ranged from 0.03 to 5.11. The LOD and LOQ for all the analytes were found to be in the range of 0.16–3.26ng/mL and 0.44–9.87ng/mL, respectively. The DPPH scavenging effects of samples were also investigated and all the samples were found to be strong scavengers of DPPH radical showing 69.50±0.01–78.60±0.10 %RSA. The established method provides a useful way for understanding the metabolite distribution in processed products of C. sinensis and to develop quality control protocols for these products.

Design, Synthesis and Bioevaluation of Two Series of 3-[(1-Benzyl-1H-1,2,3-triazol-4-yl)methyl]quinazolin-4(3H)-ones and N-(1-Benzylpiperidin-4-yl)quinazolin-4-amines.

Two series of 3-[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]quinazolin-4(3H)-ones and N-(1-benzylpiperidin-4-yl)quinazolin-4-amines were designed initially as potential acetylcholine esterase inhibitors. Biological evaluation demonstrated that N-(1-benzylpiperidin-4-yl)quinazolin-4-amines significantly inhibited AChE activity. Especially, two compounds of them were found to be the most potent with relative AChE inhibition percentages of 87 % in comparison to donepezil. The docking studies with AChE showed similar interactions between donepezil and four derivatives. N-(1-Benzylpiperidin-4-yl)quinazolin-4-amines also exhibited significant DPPH scavenging effects. The two series of compound also exerted moderate to good cytotoxicity against three human cancer cell lines, including SW620 (human colon cancer), PC-3 (prostate cancer), and NCI-H23 (lung cancer), with 3-[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]quinazolin-4(3H)-one being the most cytotoxic agent. 3-[(1-Benzyl-1H-1,2,3-triazol-4-yl)methyl]quinazolin-4(3H)-one significantly induced early apoptosis and arrested the SW620 cells at G2/M phase. From this study, two compounds of N-(1-benzylpiperidin-4-yl)quinazolin-4-amines could serve as new leads for further design and AChE inhibitors, while 3-[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]quinazolin-4(3H)-one could serve as a new lead for the design and development of more potent anticancer agents.

Preparative separation of mangiferin glycosides by high speed counter current chromatography and comparison of their antioxidant and antitumor activities.

Mangiferin, a xanthonoid with various bioactivities. The low solubility of mangiferin limits the use in pharmacological fields. In this study, high-speed counter-current chromatography (HSCCC) was used to separate and purify mangiferin glycosides from the crude sample after enzymatic glycosylation of mangiferin. Two fructosyl mangiferin were successfully purified by HSCCC with a two-phase-solvent system composed of n-butanol–methanol–water (6 : 1 : 6, v/v). A total of 18 mg of mangiferin (I), 73 mg of β-d-fructofuranosyl-(2 → 6)-mangiferin (II), and 58 mg of β-d-difructofuranosyl-(2 → 6)-mangiferin (III) were obtained in one-step separation from 150 mg of the crude sample with purities of 99.2%, 98.7% and 98.9%, respectively. The chemical structures were identified by HRMS, 1H-NMR, 13C-NMR and 2D NMR. Mangiferin glycosides showed higher antioxidant and antitumor activities compared to that of mangiferin by employing DPPH scavenging effect, reducing power and cytotoxicity assay. Therefore, these novel fructosyl mangiferin exhibit a great potential to be developed into new medicines.

Cytotoxic xanthones isolated from Calophyllum depressinervosum and Calophyllum buxifolium with antioxidant and cytotoxic activities

The stem bark of Calophyllum depressinervosum and Calophyllum buxifolium were extracted and examined for their antioxidant activities, together with cytotoxicity towards human cancer cells. The methanol extract of C. depressinervosum exhibited good DPPH and NO scavenging effects. The strongest BCB inhibition and FIC effects were shown by dichloromethane and ethyl acetate extracts of both species. Overall, DPPH, FRAP and FIC assays showed strong correlation with TPC. For cytotoxicity, hexane extract of C. depressinervosum possessed the strongest anti-proliferative activities towards SNU-1 cells while the hexane extract of C. buxifolium showed the strongest activity towards LS-174T and K562 cells with the IC50 values ranging from 7 to 17 μg/mL. The purification of plant extracts afforded eight xanthones, ananixanthone (1), caloxanthone B (2), caloxanthone I (3), caloxanthone J (4) xanthochymone B (5), thwaitesixanthone (6), 1,3,5,6-tetrahydroxyxanthone (7) and dombakinaxanthone (8). All the xanthones, except 1 were reported for the first time from both Calophyllum species. The xanthones were examined for their cytotoxic effect against K562 leukemic cells. Compounds 1 and 2 showed strong cytotoxicity with the IC50 values of 2.96 and 1.23 μg/mL, respectively. The molecular binding interaction of 2 was further investigated by performing molecular docking study with promising protein receptor Src kinase.

Chemical Constituents Isolated from Rhododendron ungernii with Antioxidant Profile

Background:Plant in Rhododendron genus that contains phenolic compounds has been used in traditional medicine and revealed considerable biological activities.Objective:Isolation and identification of antioxidant natural products from Rhododendron ungernii.Methods:Rhododendron ungernii Trautv. flowers were collected and dried in shade. The dried flowers were extracted with methanol for 3 days. The solvent was removed by reduced pressure to yield the extract which was subjected to column chromatography (Sephadex LH-20, C18 reversed phase column) to isolate catechin-7-O-glucoside (1), quercetin-3-O-β-galactoside (2), quercetin-3-O- β-xyloside (3), farrerol (4), myricetin (5), and quercetin (6). The structures of isolated compounds were elucidated by spectroscopic methods such as 1D-NMR, 2D-NMR, and LC-TOF/MS. DPPH scavenging effect, ABTS+ scavenging activity, and reducing power (FRAP) were performed for antioxidant assays of isolated natural compounds.Results:Isolated flavonoids displayed the outstanding antioxidant activities. Catechin-7-O-glucoside (1) and quercetin-3-O-β-galactoside (2) (IC50, 3.66 µg/mL) had the most DPPH• scavenging effect among the compounds. The highest ABTS•+ scavenging activity (IC50, 1.41 µg/mL) and reducing power effect (6.05 mmol TE/g comp) were observed for myricetin (5).Conclusion:R. ungernii extract and isolated compounds could be a promising antioxidant for food and pharmaceutical industries.

Extracts from the trunk bark of Distemonanthus benthamianus Baillon. (Caesalpiniaceae) developed antidiarrhoeal activities in rats and mice

Distemonanthus benthamianus is used in Cameroon to treat diarrhoeal episodes. The study aimed to evaluate its antidiarrhoeal potential in Wistar rats and BALB/c mice. Extracts were preliminary investigated for phytochemical components, total phenols quantification and DPPH scavenging activity. Their effects were also evaluated against castor oil-induced diarrhoea, prostaglandin-E1-induced fluid accumulation, charcoal meal motility test, as well as against magnesium sulphate-induced diarrhoea and electrolytes regulation. The methanolic extract contains alkaloids, flavonoids, polyphenols, saponins, sterols, tannins and triterpenes while aqueous extract was devoid of sterols and triterpenes. Phenolic compounds were more concentrated in methanolic extract, which also developed significant DPPH scavenging effects. In castor oil-induced diarrhoea, significant (p < 0.001) reduction in diarrhoeal stools frequency was observed with 100, 200 and 300 mg/kg of aqueous extract, while 400 mg/kg of methanolic extract exhibited maximum effect. Total stools frequency was significantly (p < 0.001) reduced with doses of 300 and 400 mg/kg of extracts. Maximum protection was obtained with 400 mg/kg of both extracts in magnesium sulphate-induced diarrhoea. That dose significantly (p < 0.001) reduced Na+ excretion, while Ca2+ excretion was significantly (p < 0.001) increased with 100 mg/kg of aqueous extract. Both extracts significantly (p < 0.01, p < 0.001) reduced the intestinal fluids mass and volume similarly compared to the negative control groups. The gut motility was significantly (p < 0.001) reduced with 100 and 200 mg/kg of methanolic and aqueous extracts, respectively. Extracts are therefore antidiarrhoeal remedies candidates, since they provoked a decrease in intestinal motility, associated with fluid and electrolytes regulation across the gut.

In vitro Antidiabetic, Antioxidant and Anti-lipid peroxidative Activities of Corn Steep Liquor Extracts of Curculigo pilosa and its Solvent Fractions

ABSTRACTThe in vitro antioxidant, antidiabetic, and antiperoxidative activities of corn steep liquor extract of Curculigo pilosa, and its solvent fractions in n-butanol and methanol were evaluated. The antioxidant ability was evaluated by total phenolic content (TPC), total flavonoid content (TPC), total antioxidant capacity (TAC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability and reducing capacity, antidiabetic activity by ability to inhibit α-amylase and α-glucosidase enzymes though antiperoxidative activity was evaluated by the ability to inhibit Fe2+-induced lipid peroxidation in pancreas. The results showed that the crude extract (CRD) had the highest TPC (63.39 mg GAE 100 g−1), TFC (48.70 mg QUE 100 g−1), and TAC (24.72 mg AAE 100 g−1), which culminated to higher DPPH scavenging effect, reducing power, and lipid peroxidation inhibition in pancreas homogenate. CRD demonstrated the highest ability to inhibit α-amylase and α-glucosidase enzymes.

Glucosinolates metabolism and redox state of rocket ( Eruca sativa Mill.) during germination

Isothiocyanates (ITCs) exhibit anticancer and antioxidant activity. ITCs are formed from the catalysis of glucosinolates (GLs) by myrosinase (MYR) in Brassicaceae vegetables. This study investigated the GL content, MYR activity, ITC formation, and redox state of rocket upon germination. Banye and Dongsheng were selected from four cultivars by determining growth state and ITC metabolism. In both cultivars, GL levels were the highest on the second day of germination and significantly declined on the eighth day. The 4-day-old sprouts had the highest ITC level. MYR exhibited maximal activity in Banye and Dongsheng on the fourth and the second day of germination, respectively. Regarding the antioxidant system, the sprouts had more chlorophyll, total phenol, and anthocyanin content, and they had higher DPPH scavenging effects compared with raw seeds. Moreover, Dongsheng showed greater scavenging capacity than Banye in general. Practical applications Rocket belongs to the Brassicaceae family, which has been widely considered a good source of bioactive components to prevent tumor formation and reduce the incidence of cardiovascular disease and cancer given the abundance of glucosinolate (GLs). GLs could be catalyzed by myrosinases (MYR) and converted into biologically active products including isothiocyanates (ITCs). After germination, MYR is activated and more ITCs are produced. Using rocket sprouts as a daily diet or raw material is beneficial for human health.

Cytotoxic polyphenolic compounds from Lespedeza bicolor stem bark

Four new pterocarpans (6aR,11aR)-6a,11a-dihydrolespedezol A2 (2), (6aR,11aR)-2-isoprenyl-6a,11a-dihydrolespedezol A2 (3), (6aR,11aR,3′R)-6a,11a-dihydrolespedezol A3 (4), (6aR,11aR,3′S)-6a,11a-dihydrolespedezol A3 (5) and one new stilbenoid with 1,2-diketone fragment named bicoloketone (6) along with one previously known pterocarpen lespedezol A2 (1) have been isolated from Lespedeza bicolor stem bark using multistage column chromatography on polyamide and silica gel. The structures of the isolated polyphenolic compounds were determined by spectroscopic methods. The absolute configurations of 4 and 5 were determined by comparison of their electronic circular dichroism (ECD) spectra obtained experimentally and the spectra calculated using time-dependent density functional theory (TDDFT). The isolated compounds exhibited a moderate DPPH scavenging effect and ferric reducing power compared to the reference antioxidant quercetin. The cytotoxicity of compounds against three human cancer cell lines, HTB-19, Kyse-30, and HEPG-2, and two normal cell lines, RPE-1 and HEK-293, was tested using the MTT assay. Compound 3 showed the strongest cytotoxic activity against all cell lines (IC50 6.0–19.1 μM) compared with the positive control cisplatin. The other tested compounds possessed moderate cytotoxic activity against cancer cells.