Determined Using 2,2-diphenyl-1-picrylhydrazyl Research Articles

DETERMINATION OF ANTIOXIDANT, ANTI-AGING AND CYTOTOXICITY ACTIVITY OF THE ESSENTIAL OILS FROM CINNAMOMUM ZEYLANICUM

Antioxidant activity, anti-aging effects and cytotoxicity activity of cinnamon essential oils from Cinnamomum zeylanicum were investigated in this study. The antioxidant activities of the cinnamon essential oil at the concentrations of 125, 250, 500, and 1000 µg/mL were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2ʹ-azino-bis (3-ethylbenzo-thiazoline-6-sulfonic acid) diammonium salt (ABTS). The inhibitory activities against collagenase, elastase and tyrosinase were evaluated for anti-aging effects. The antioxidant activity determined by DPPH and ABTS assays varied from 4.91 - 28.74% and 4.96 - 50.17%, respectively. In addition, cinnamon essential oil at all concentrations tested (100, 200, 500, and 1000 µg/mL) inhibited tyrosinase activity by 61.68 - 93.12 %, collagenase activity by 2.83 - 30.28 % and elastase activity by 4.37 - 33.92 %. The cytotoxicity activity determined by the diphenyltetrazolium (MTT) assay revealed that the cinnamon essential oil at the concentration less than 100 µg/mL did not exhibit cytotoxicity activity on human fibroblast cells while the percentage of cell viability decreased when exposed to this oil at the concentration higher than 150 µg/mL. These results demonstrated that the cinnamon essential oil has antioxidant, tyrosinase inhibitory, collagenase inhibitory, and elastase inhibitory activities. In addition, cinnamon essential oil at each effective concentration did not show any toxicity when tested on normal human fibroblast cell. Therefore, this essential oil could be a potential candidate for cosmetic and pharmaceutical products.

Total Phenolic, Total Flavonoids Content and Antioxidant Activity of Mangifera sp. Leaf Extracts

Mangifera sp. is a versatile plant that was reported to have various bioactivities, however only the fruits have gain popularity due to it sweet flesh and been known worldwide. It has a potential source of flavonoids and carotenoids, which makes them a nutritious functional food to consume. This study focused on determination of the total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity of the Mangifera sp. leaves extract in different water extraction methods. The TPC and TFC was determined by using Folin-Ciocalteu method and aluminium chloride method respectively while antioxidant activity was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and ferric reducing antioxidant power (FRAP) assay. Soxhlet extraction (SXE) produced the highest extraction yield compared to microwave extraction (MWE). MWE at 8 minutes extract showed the highest TPC (262.13±0.05 mg GAE/g). SXE showed the highest TFC (413.46±0.77 mg rutin/g). The highest antioxidant activity was recorded in MWE 8 minutes extract through DPPH and FRAP assays compared to other two MWE extract and SXE extract.

In vitro Antioxidant Activities of Ethanol, Ethyl Acetate and n-Hexane Extracts of Mangifera indica Leaves

Mangifera indica leaves have been in use in folk medicine since ancient time, for the treatment and/or management of numerous health complications. In this study, total phenols and flavonoids contents, as well as in vitro antioxidant activities of ethanol, ethyl acetate and n-hexane extracts of M. indica leaves were determined and compared. The in vitro antioxidant activities were determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, ferric reducing antioxidant power, and inhibition of lipid peroxidation assays, respectively. The total phenols were found to be present in the descending order of; ethanol extract > ethyl acetate extract > n-hexane extract, while flavonoids were observed in the descending order of; n-hexane extract > ethanol extract > ethyl acetate extract. The maximum percentage DPPH radical scavenged (at 100 μg/mL), ferric reducing power (at 400 μg/mL) and inhibitory activity on lipid peroxidation (at 400 μg/mL) exhibited by the ethanol extract (94.40%, 88.73%, and 84.05%, respectively) were significantly greater (p < 0.05) than the ethyl acetate extract (79.46%, 68.74%, and 79.73%, respectively at 400 μg/mL) as well as n-hexane extract (45.30%, 58.79%, and 67.78%, respectively at 100 and 400 μg/mL). It can be concluded that the extracts possess anti-oxidant activities and may be employed in the treatment and/or management of oxidative stress related diseases.
 Keywords: Mangifera indica; phenolics; flavonoids; antioxidant; DPPH radical;

Cornus officinalis Ethanolic Extract with Potential Anti-Allergic, Anti-Inflammatory, and Antioxidant Activities.

Atopic dermatitis (AD) is an allergic and chronic inflammatory skin disease. The present study investigates the anti-allergic, antioxidant, and anti-inflammatory activities of the ethanolic extract of Cornus officinalis (COFE) for possible applications in the treatment of AD. COFE inhibits the release of β-hexosaminidase from RBL-2H3 cells sensitized with the dinitrophenyl-immunoglobulin E (IgE-DNP) antibody after stimulation with dinitrophenyl-human serum albumin (DNP-HSA) in a concentration-dependent manner (IC50 = 0.178 mg/mL). Antioxidant activity determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, ferric reducing antioxidant power assay, and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity, result in EC50 values of 1.82, 10.76, and 0.6 mg/mL, respectively. Moreover, the extract significantly inhibits lipopolysaccharide (LPS)-induced nitric oxide (NO) production and the mRNA expression of iNOS and pro-inflammatory cytokines (IL-1β, IL-6, and TNF-α) through attenuation of NF-κB activation in RAW 264.7 cells. COFE significantly inhibits TNF-α-induced apoptosis in HaCaT cells without cytotoxic effects (p < 0.05). Furthermore, 2-furancarboxaldehyde and loganin are identified by gas chromatography/mass spectrometry (GC-MS) and liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis, respectively, as the major compounds. Molecular docking analysis shows that loganin, cornuside, and naringenin 7-O-β-D-glucoside could potentially disrupt the binding of IgE to human high-affinity IgE receptors (FceRI). Our results suggest that COFE might possess potential inhibitory effects on allergic responses, oxidative stress, and inflammatory responses.

Chemical Composition and Antioxidant Potential of Fruit Essential Oil of Laggera pterodonta (DC.) Benth Grown in North Central, Nigeria

This study aimed at isolating, characterizing and evaluating the antioxidant potential of fruit essential oil of Laggera pterodonta native to Nigeria. Pulverized fruits (500 g) of L. pterodonta were hydrodistilled for 3 hours and yielded 0.07±0.02 % (w/w) of essential oil. The oil was analyzed using GC and GC-MS. The analyses revealed the predominance of sesquiterpenoids (92.7 %), while monoterpenoids constituted 1.5 % of the oil. The major compounds in the oil were α-bergamotene (29.3 %), β-bisabolene (16.9 %), α-copaene (8.8 %) and α-bisabolol (6.0 %). Terpinen-4-ol (0.5 %) and α-terpineole (1.0 %) were the only monoterpenoids detected in the oil. The antioxidant activity of the oil was determined using 2,2-diphenyl- 1-picryl hydrazyl (DPPH) radical scavenging assay. The oil exhibited antioxidant activity by scavenging DPPH radicals with IC50 of 6.05 μL/mL. The activity of the oil was higher than the activity of ascorbic acid with IC50 of 12.84 μl/ml used as standard. Therefore, the oil could serve as an alternative to synthetic drugs for the amelioration of oxidative stress.

Variation in bioactive compounds, antioxidant and antibacterial activity of Iranian Chrysanthemum morifolium cultivars and determination of major polyphenolic compounds based on HPLC analysis.

In this study, chemical profiling, phenolic and flavonoid contents, as well as the antibacterial and antioxidant activity of 17 Iranian Chrysanthemum morifolium cultivars were evaluated. The high performance liquid chromatography analysis revealed the presence of eight compounds with the major constituents including chlorogenic acid (0-934.7mg/100g), ferulic acid (12.7-171.6mg/100g), rutin (0-225.8mg/100g) and luteolin (2.83-213.5mg/100g). The cultivar "Ashna" with 63.6mg tannic acid equivalents g-1 DW had the highest amount of total phenol, while the highest flavonoid content (13.52mg quercetin equivalents g-1DW) was observed in cultivar "Shokoh". The antioxidant activities of the samples were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the reducing power assay. The results showed that the cultivars "Poya3" (IC50 = 385.7) and "Dorna2" (IC50 = 489.4) possessed a higher antioxidant activity than the others in DPPH model system. Antimicrobial activity was also evaluated based on minimal inhibitory concentration (MIC) and minimal bactericidal concentration values. MIC values were in the range of 5-10mgml-1 against Salmonella enterica and Bacillus cereus and 10-20mgml-1 against Staphylococcus aureus and Escherichia coli. Finally, Chrysanthemum cultivars with high bioactive compounds were introduced for beneficial usage in food and industrial applications.

Effect of 1-methylcyclopropene on the aroma volatiles, polyphenols contents, and antioxidant activity of post-harvest ripening peach (Prunus persica L.) fruit

Peach is a perishable fruit that quickly loses its aroma and bioactive components during storage. In this article, we evaluated the effect of treatment with 1-methylcyclopropene (1-MCP) on the quality of stored peaches depending on shelf-life temperature. Ethylene production and aroma content were determined using gas chromatography mass spectrometry (GC-MS). Polyphenol levels were monitored using high-performance liquid chromatography (HPLC), and the antioxidant capacity of peach samples was determined using 2,2-diphenyl-1 picrylhydrazyl (DPPH), 2,2?-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and ferric reducing antioxidant power (FRAP) assays. We found that treatment with 1-MCP could delay the ripening process and reduce the decay of peach fruit depending upon shelf-life temperature. Furthermore, treatment with 1-MCP efficiently delayed climacteric ethylene production, maintained high levels of total soluble solids (TSS), titratable acidity and characteristic lactones, including ?-decalactone, ?-decalactone, ?-octalatone, jasmine lactone and ? dodecalactone. Moreover, treatment with 1-MCP also helped maintain high levels of chlorogenic acid, L epicatechin, catechin, quercetin-3-rutinoside and neochlorogenic acid, as well as high antioxidant activity. Principal component analysis showed that treatment with 1-MCP during the second week of storage coincided with activity of lactones, poly-phenols and antioxidants, which was consistent with changes in phytochemicals. These results revealed that treatment with 1-MCP offers potential as a preservation strategy for maintaining the flavour and nutritional quality of peach fruit under shelf-life conditions.

Characterization of Green and Yellow Papaya for Antioxidation and Glucose Uptake Stimulatory Activity in HepG2 Liver Cells

Abstract Objectives The long-term objective of present research is to evaluate papaya for anti-diabetic properties. The current objectives were (1) To determine polyphenolic contents and antioxidation activity of leaves, skin, pulp, and seeds of green and yellow papaya and (2) to evaluate their effects on glucose uptake in HepG2 liver cells. Methods The leaves, skin, pulp, and seeds samples were freeze dried and then extracted in water or 80% Methanol. The total phenolic contents of each extracted sample was determined using the Folin- Ciocalteu method. The antioxidation activity in each sample was determined using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and Ferric ion reducing antioxidation power (FRAP) assays. Effect of each fraction on glucose uptake was determined using a fluorescent-tagged NBD-Glucose derivative. Results The concertation of polyphenols was highest in both water and methanol extracts of seeds from yellow papaya compared to that in seeds from green papaya. Leaves and skin fractions contained modest concentration of polyphenols whereas pulp contained the lowest concentration of polyphenols. FRAP assay indicates that both water and methanol extracts of leaves, skin, pulp, and seeds from yellow papaya exhibited higher antioxidation activity compared to that of green papaya. A similar antioxidation activity pattern was observed by DPPH assay. Leaves and skin from both green and yellow papaya showed modest to high antioxidation activity whereas pulp from both green and yellow papaya contained a low antioxidation activity. In contrast, green papaya extracts significantly stimulated glucose uptake in HepG2 liver cells compared to that of yellow papaya extracts. Both water and methanol extract of pulp from green papaya showed the greatest stimulation of glucose uptake followed by leaves and skin. Conclusions Although the seeds from yellow papaya contained highest concentration of polyphenols and exhibited highest antioxidation activity, pulp from green papaya showed significantly higher stimulation of glucose uptake in liver cells. Our data indicates that polyphenolic content and/or antioxidation activity in papaya may not be related to their glucose uptake stimulatory activity in liver cells. This study concludes that regular consumption of green papaya may be beneficial for preventing diabetes. Funding Sources Capacity Building Grant, USDA.

Chemical composition and antioxidant activity of &lt;i&gt;Waltheria Indica&lt;/i&gt; Linn whole plant

Waltheria indica is a promising medicinal plant belonging to family Malvaceae, which many biological activities of the solvent extracts of its various parts have been scientifically evaluated. The aim of this study was to evaluate and analyze the minerals, crude fibre and fat contents, the phytochemical constituents as well as the antioxidants activity of the powder sample of W. indica whole plant. Fresh sample of whole W. indica plant was collected and airdried at room temperature. The mineral constituents were determined by spectrophotometry. The crude fibre, fat contents and the qualitative and quantitative phytochemical compositions were determined using standard analytical procedure. The antioxidants activity was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric reducing antioxidant potential (FRAP) assays. The mineral analysis results revealed the presence of micro and macro nutrients such as potassium, calcium, magnesium and manganese among others which are within the acceptable health range. The values (23.8%; 0.15%) obtained for both crude fibre and fat contents were reasonable. The qualitative phytochemical screening established the presence of alkaloids, terpenoids, flavonoids, tannins, anthraquinones and phenol. Steroids are in abundance while Cardiac glycosides are absent. The quantity of alkaloids (1.9%), saponins (1.4%), flavonoids (3.1%) and tannins (17422μg/GAE) are in appreciable amount which may be responsible for its various activities. W. indica showed good inhibitory scavenging activity and better reducing ability compared to ascorbic acid. The results obtained from this study provide further scientific evidence to support the ethno-medicinal information on the uses of W. indica in the treatment of various health issues.

&lt;i&gt;In vivo&lt;/i&gt; antimalarial activity of methanol extracts and fractions of &lt;i&gt;Brachystegia eurycoma&lt;/i&gt; and &lt;i&gt;Mondia whitei&lt;/i&gt;on chloroquine-resistant &lt;i&gt;Plasmodium berghei&lt;/i&gt;

Malaria remains a major public health problem in the tropics. According to WHO estimates, sub-Saharan Africa continues to carry a disproportionately high share of global malaria burden. Oxidative stress plays significant role in malaria pathogenesis. Recently, there is increasing effort to develop more potent antimalarials from plant source. Brachystegia eurycoma and Mondia whitei are used locally for malaria treatment. Medicinal plants used in therapy quite often possess antioxidant activities as a result of its inherent phytoconstituents. The phytochemical composition of Brachystegia eurycoma and Mondia whitei were qualitatively examined. The antioxidant activities of the methanolic extracts of the leaves of two medicinal plants were determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant assay. The Brine shrimp lethality assay (BSLA) and Lorke‘s acute toxicity study were used to estimate their toxicities; while Peter‘s 4-day chemosuppresive test was employed to evaluate their antimalarial activities. The flavonoid and saponins content were particularly high in both plants. Using ascorbic acid as reference (IC50 9.26 μg/mL), the antioxidant IC50 values of B. eurycoma and M. whitei were 11.14 μg/ mL and 19.81μg/mL respectively; the BSLA LC50 were 1.8 mg/mL and 1.2 mg/mL; acute toxicity LD50 were 5000 mg/kg and 4500 mg/kg. Brachystegia eurycoma showed stronger daily average antimalarial activity (62.0 %) than Mondia whitei (39.3%), the standard drug, chloroquine, was 85.4%. The chloroform fraction of Brachystegia eurycoma was the most active with (65%) daily average suppression. This suggests that the extracts of leaves of the plants have good antioxidant activities, are non-toxic and supports their antimalarial use in ethnomedicine.

Chemical compositions of essential oils of Amomum verum and Cinnamomum parthenoxylon and their in vitro biological properties

Introduction: In eastern Thailand, Amomum verum and Cinnamomum parthenoxylon are native plants used by local communities for their medical and culinary properties. This study determined the chemical composition and biological activities of the essential oils from A. verum shoots (AVSEO) and C. parthenoxylon wood (CPW-EO). Methods: Essential oils were extracted using hydro-distillation and analyzed using gas chromatography-mass spectroscopy (GC-MS). The antimicrobial activity was evaluated using the disc diffusion method and broth microdilution assay. The cytotoxic activity of the essential oils was assessed against the human prostate adenocarcinoma (DU145) cell line using 3-(4,5-dimethylthiazol2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The antioxidant activity of the essential oils was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis-(3-ethylbenzothiazoline6-sulfonic acid) (ABTS) radical scavenging assays. The expression of antioxidant genes in the DU145 cells was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR). Results: 1,8-Cineole was the main component in AVS-EO and CPW-EO with 84.38, and 45.65 %, respectively. AVS-EO had stronger antimicrobial activity than CPW-EO. The lowest minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) values of AVSEO against Candida albicans were 0.3125 and 2.5 mg/mL, respectively. Both essential oils had timedependent and dose-dependent cytotoxic effects on the DU145 human prostate adenocarcinoma cells. CPW-EO had high antioxidant activity toward DPPH and ABTS radicals with IC50 values of 4.528±0.233 and 0.045±0.007 mg/mL, respectively. The two essential oils up-regulated glutathione peroxidase (GPx) and glutathione reductase (GRx) mRNA expression in the oxidative stress response of DU145 cells. Conclusion: AVS-EO and CPW-EO might be added as natural ingredients in food or dietary supplement products for the benefit of microbial and prostate cancer inhibition.

FORMULATION OF SERUM GEL CONTAINING ANGELICA KEISKEI LEAF EXTRACT AS AN ANTIOXIDANT AND TYROSINASE ENZYME INHIBITOR

Objective: The aim of this study was to formulate and evaluate the efficacy of Angelica keiskei (AK) leaf extract in serum gel as an antioxidant and tyrosinase enzyme inhibitor.&#x0D; Methods: The leaves of AK were extracted using the maceration method, while the antioxidant and tyrosinase enzyme inhibitory activities were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and L-Tyrosine as assay and substrate, respectively. Subsequently, the extract was formulated into serum gel and evaluated for physical stability, antioxidant and inhibitory activity to tyrosinase enzyme.&#x0D; Results: The results showed that AK leaf extract has antioxidant activity, with an IC50 value = 7.73 mg/ml, while the tyrosinase enzyme inhibitory power had an IC50 value = 500 mg/ml. Based on physical stability, the serum gel was stable after 28 d of storage. The serum gel of AK leaf extract also showed antioxidant activity and tyrosinase enzyme inhibition with IC50 value of 16.68 mg/ml and 741.62 mg/ml, respectively.&#x0D; Conclusion: This study demonstrated that the serum gel of AK leaf extract has potential as a skin lightening agent and is safe for use as a topical preparation.

Screening of Phytochemicals and Antioxidant Potential of Leaves Extract of Litsea glutinosa

Litsea glutinosa (Lour) leaves are deliberated as worthy traditional medicine. The aim of this study was to screen the phytochemicals, to evaluate the total flavonoid contents as well as antioxidant activity of various extract of Litsea glutinosa (Lour). The phytochemical analysis of each solvent extract was also carried out. Total flavonoid content was determined by aluminium chloride colorimetric assay. Antioxidant activity was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), Ferric reducing ability of plasma (FRAP) and Hydrogen Peroxide (H2O2) free radical scavenger methods. Phytochemical screening of various extract revealed the presence of Alkaloids, Flavonoids, Diterpenes, Proteins, Carbohydrate and Saponins. The total flavonoid content was found 1.89, 5.01 and 3.16 mg/100mg of dry weight of pet ether, ethanol and aqueous extract respectively, expressed as Quercetin equivalents. Antioxidant activity was performed using three methods DPPH, Ferric reducing ability of plasma (FRAP) assay and Hydrogen Peroxide scavenging activity. Our current results emerged that Litsea glutinosa (Lour) act as an antioxidant agent due to its free radical scavenging. So, the plant may be further pursued to find out for its pharmacological active natural products.&#x0D; Keywords: Litsea glutinosa (Lour), Qualitative, Quantitative phytochemical, Antioxidant activity.

Biosynthesis of Silver Nanoparticles Using Cucumis prophetarum Aqueous Leaf Extract and Their Antibacterial and Antiproliferative Activity Against Cancer Cell Lines.

Biosynthesized nanoparticles are gaining attention because of biologically active plant secondary metabolites that help in green synthesis and also due to their unique biological applications. This study reports a facile, ecofriendly, reliable, and cost-effective synthesis of silver nanoparticles using the aqueous leaf extract of Cucumis prophetarum (C. prophetarum) and their antibacterial and antiproliferative activity. Silver nanoparticles were biosynthesized using the aqueous leaf extract of C. prophetarum, which acted as a reducing and capping agent. The biosynthesized C. prophetarum silver nanoparticles (Cp-AgNPs) were characterized using different techniques, such as UV–visible spectroscopy, dynamic light scattering (DLS), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray analysis (EDAX). Phytochemical analysis was performed to determine the phytochemicals responsible for the reduction and capping of the biosynthesized Cp-AgNPs. The antioxidant activity of the biosynthesized nanoparticles was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. Their antibacterial activity was checked against Staphylococcus aureus (Gram-positive) and Salmonella typhi (Gram-negative) bacteria. The biosynthesized nanoparticles showed dosage-dependent inhibition activity with a significant zone of inhibition and were more effective toward S. typhi as compared to S. aureus. Their antiproliferative activity was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on selected cancer cell lines. The IC50 values of Cp-AgNPs on A549, MDA-MB-231, HepG2, and MCF-7 were found to be 105.8, 81.1, 94.2, and 65.6 μg/mL, respectively, and this showed that the Cp-AgNPs were more potent toward MCF-7 as compared to other cell lines used in this study. This work revealed that the biosynthesized silver nanoparticles using C. prophetarum leaf extract were associated with good antibacterial activity and antiproliferative potential against selected cancer cell lines. The biosynthesized C. prophetarum AgNPs can be further exploited as a potential candidate for antioxidant, antibacterial, and anticancer agents.

Phytochemical screening, total hydroxycinnamic acids, total phenolic and antioxidant activity of Lavandula angustifolia Mill

The aim of this study was the screening of phytochemicals and determination of total hydroxicinamic acids, total polyphenols and antioxidant activity of hydroalcoholic extract ofLavandula angustifolia Mill. cultivated in Craiova - Romania. Phytochemical screening showed that all of samples are positively. Quantitative determination of hydroxycinnamic acids was calculated as chlorogenic acid equivalent in % of dried plant raw material. The total polyphenol content was measured using the Folin Ciocalteu reagent colorimetric method. Antioxidant activity was determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenger methods. It has established that in sample ofLavandula angustifoliathe total content of hydroxycinnamic acid derivates is 2.65%, total polyphenols 1.4 mg GAE g-1 DW. The hydroalcoholic extract displayed DPPH free radical scavenging activity with 85.7%.

Chemical composition, antioxidant potential and antimicrobial activities of Ixora scheffleri subspecies keniensis essential oil

Background: Essential oil (EO) obtained from Ixora scheffleri subspecies (subsp.) keniensis has valuable biological properties and can play a possible therapeutic role because of its antimicrobial and antioxidant nature. Aim: In this article, the chemical constituents, antimicrobial activity and antioxidant capacity of the EO obtained from Ixora scheffleri subsp. keniensis were determined using standard procedures. Setting: Plant material collection, essential oils extractions and antimicrobial assays were performed at Jomo Kenyatta University of Agriculture and Technology (JKUAT), Department of Botany Laboratories. Gas Chromatography Mass Spectrophotometry (GC/MS) analysis was carried out at the Physical Science Laboratory, MacEwan University, Canada. Methods: The chemical constituents were determined using GC/MS. The total phenol content was evaluated using the Folin–Ciocalteu procedure. The antioxidant activity was determined using 2,2-diphenyl-1- picrylhydrazyl (DPPH) and β -carotene linoleic acid assays. The antimicrobial assay was performed using the disc diffusion method. Results: The total phenol content of the EO was estimated to be 91.6 µ g/mg ± 0.5 µ g/mg. The antioxidant activity of EO obtained from Ixora relative to ascorbic acid was found to be 52% using the β -carotene linoleic acid assay. The DPPH scavenging activity of 30 µ g/mL EO obtained from Ixora and 30 µ g/mL ascorbic acid was 81.65% and 97.0%, respectively. The EO was found to have significant susceptibility against Escherichia coli , and intermediate susceptibility against Candida albicans . However, Staphylococcus aureus, Bacillus subtilis and Pseudomonas aeruginosa showed complete resistance. Conclusion: The in vitro chemical compositional analysis of EO obtained from Ixora scheffleri subsp. keniensis confirms the presence of phenolic compounds attesting to the antioxidant properties and antimicrobial properties.

Antioxidant capacity and HPLC determination of phenolic in different organs of Calligonum polygonoides subspecies comosum

Background: Calligonum polygonoides subsp. comosum is a perennial desert plant. Most of the previous chemical investigation of this plant was performed on the whole herb but there were no data about quantification of active constituent in different organs of C. polygonoides. Materials and Methods: in vitro antioxidant activity, total phenolic, and total flavonoid contents of the different organs were determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH), Folin–Ciocalteu, and aluminum chloride (AlCl3) methods, respectively. Quantitative analysis of the phenolic compounds was determined in the different organs of the plant using high-performance liquid chromatography (HPLC). Results: Both bark and leaves showed the highest radical scavenging activity with the values of 450.30 and 398.10 μg/g ascorbic acid equivalent, respectively. The total phenolic content of the samples was in the range of 27.9–281.5 μg/g gallic acid equivalent and total flavonoid content of the samples was in the range of 53.9–257.4 μg/g rutin equivalent where the leaves and bark showed the highest contents. HPLC analysis showed that flavonol glycosides content was higher in all organs compared to the aglycones. Flowers and fruits were the richest organs in flavonols, whereas leaves, stems, and bark were the richest in taxifolin and catechin. Conclusion: Depending on the obtained results C. polygonoides is an excellent source of natural antioxidants.

Preparation, carbonic anhydrase enzyme inhibition and antioxidant activity of novel 7-amino-3,4-dihydroquinolin-2(1H)-one derivatives incorporating mono or dipeptide moiety

New dipeptide–dihydroquinolinone derivatives were successfully synthesised by benzotriazole mediated nucleophilic acyl substitution reaction and their structures were elucidated by spectroscopic and analytic techniques. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was determined against four human (h) isoforms, hCA I, hCA II, hCA IX and hCA XII. While all compounds showed moderate to good in vitro CA inhibitory properties against hCA IX and hCA XII with inhibition constants in the micromolar level (37.7–86.8 and 2.0–8.6 µM, respectively), they did not show inhibitory activity against hCA I and hCA II up to 100 µM concentration. The antioxidant capacity of the peptide–dihydroquinolinone conjugates was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method. Most of the synthesised compounds showed low antioxidant activities compared to the control antioxidant compounds BHA and α-tocopherol.

Trans-resveratrol, piceatannol and gallic acid: Potent polyphenols isolated from Mezoneuron benthamianum effective as anticaries, antioxidant and cytotoxic agents

Phytochemical investigation of the ethyl acetate extract of the root of Mezoneuron benthamianum, a shrub commonly used as chewing stick in the southwest of Nigeria, led to the isolation of three compounds characterised as trans-resveratrol, piceatannol and gallic acid by the use of spectroscopic techniques. The anticaries activity of the polyphenols was evaluated against four oral bacteria pathogens (Streptococcus mutans, Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli), isolated from clinical samples presented by patients having dental caries, while their antioxidant and cytotoxic activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and brine shrimp (artemia salina nauplii) bioassay techniques. The results showed that the isolated compounds exhibited very strong anticaries activity with minimum inhibitory concentration (MIC) ranging from 25 to 300 µg/ml, antioxidant activity with IC50 of 35.81, 30.35 and 11.73 µg/ml, when compared with ascorbic acid (IC50 = 38.20 µg/ml) and cytotoxic activity with LC50 of 7.15, 99.99 and 98.71 µg/ml for resveratrol, piceatannol and gallic acid respectively The isolated compounds demonstrated very strong anticaries, antioxidant and cytotoxic activities. This study further justifies the ethno-medicinal use of M. benthamianum as an effective tool in maintaining oral hygiene.

Effects of different extraction methods on yield, purity, composition, antioxidant and antimicrobial activities of phenolics from peony flowers

In the present study, microwave-assisted extraction (MAE), ultrasound-microwave synergistic extraction (UMSE) and conventional liquid–solid extraction (CLSE) methods were performed to extract the phenolics from ground peony flowers. For MAE and UMSE, the effect of extraction conditions (microwave power, extraction time, solid/solvent ratio, ethanol concentration) on the yield of phenolics was evaluated. Optimum conditions were determined in experiments where a single factor was varied. Under optimal conditions, yield, purity, composition, antioxidant and antimicrobial activities of the phenolics from the different extracts were analyzed. The antioxidant activities were determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and reducing power assays. Thus, the half-maximal inhibitory concentration (IC50) was defined for the different extraction procedures in both DPPH and ABTS assays. The antimicrobial activities of the extracts were determined using an agar well diffusion assay. Although CLSE extracts exhibited the strongest free radical scavenging activities for both ABTS (IC50 = 11.35 ± 0.36 μg/mL) and DPPH (IC50 = 18.07 ± 0.21 μg/mL), and displayed the greatest reducing power, they also had the weakest inhibitory activities for all tested bacteria. Conversely, MAE extracts exhibited the largest zone of inhibition for Escherichia coli (E. coli) (14.00 ± 1.00 mm), Streptococcus mutans (S. mutan) (13.75 ± 0.50 mm), and Streptococcus agalactiae (S. agalactiae) (12.00 ± 0.10 mm), indicating that MAE extracts exerted the best antimicrobial activities. Therefore, the CLSE method should be selected for producing the strongest antioxidant activities and the MAE procedure for generating the strongest antimicrobial activities.