Nitric Oxide Radical Scavenging Assays Research Articles

ANTIOXIDANT PROPERTIES OF SINAPIC ACID: IN VITRO AND IN VIVO APPROACH

Objective: This study was aimed to evaluate the antioxidant potential of sinapic acid in both in vitro and in vivo. Recently, we have reported that oral administration of sinapic acid (3,5-dimethoxy 4-hydroxycinnamic acid) an active phyto ingredient widely distributed in rye, mustard, berries, and vegetables has been shown to ameliorate hyperglycemia.Methods: Experimental Type 2 diabetes was induced in male Wistar rats by feeding high-fat diet to induce insulin resistance followed by intraperitoneal administration of a single low dose streptozotocin (35 mg/kg body weight [bw]). Sinapic acid was administered orally at a concentration of 25 mg/kg bw/rat/day for 30 days, and its efficacy was compared with metformin. In vitro, antioxidant scavenging properties of sinapic acid were determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), superoxide, and nitric oxide (NO) assay.Results: Sinapic acid treatment showed a significant decline in the levels of lipid peroxides, hydroperoxides and protein carbonyls in the plasma and vital tissues of diabetic rats. The treatment also improved the antioxidant status in diabetic rats indicating the antioxidant potential of sinapic acid. In addition, the results of DPPH, ABTS, superoxide, and NO radical scavenging assays substantiate the free radical scavenging efficacy of sinapic acid.Conclusion: The results of this study evidenced that sinapic acid possess significant antioxidant properties which in turn may be responsible for its antidiabetic properties.

Gas chromatography-mass spectrometry analysis and in vitro antioxidant potential of ajwain seed (Trachyspermum ammi L.) essential oil and its extracts

The aim was to study the composition of ajwain seed oil by gas chromatography-mass spectrometry (GC-MS) and to evaluate antioxidant activity of ajwain seed oil, its fractions, extracts, thymol, and its derivatives. GC-MS analysis of ajwain seed essential oil showed the presence of 47 compounds. Thymol (31.40%) was found to be the major component while γ-terpinene, isobornyl isobutyrate, and p-cymene were minor compounds. The antioxidant potential of selected components was evaluated using 2, 2-diphenyl-1-picrylhydrazyl, hydroxyl, nitric oxide radical scavenging and ferric reducing antioxidant power assays. Results demonstrated that methanol extract exhibited higher antioxidant activity in 2,2-diphenyl-1-picrylhydrazyl (IC50 value 130 µg/mL), Hydroxyl radical (IC50 value 120 µg/mL), nitric oxide (IC50 value 90 µg/mL) scavenging assays, and highest ferric reducing antioxidant power (FRAP) value (780 µg Fe (II)/g dry weight) as compared to hexane and dichloromethane extracts. Total phenolic (16.52 mg gallic acid equivalents/g) and flavonoid contents (3.89 mg quercetin equivalent/g) were also found to be higher in methanol extract compared to other extracts and ajwain oil. Practical applications Degradation of food materials by oxidation and its prevention during production, storage, and distribution is an important issue in the food industry. Due to the potential carcinogenic effect of some synthetic antioxidants, much attention has been paid to naturally-derived compounds having potential to act as antioxidants. The present study revealed that the methanol extract of ajwain seeds which contained terpenoids, phenols, and flavonoids as essential phytochemicals have high antioxidant properties, which can provide opportunities for use in pharmaceutical, nutraceutical, and food industries.

PHARMACOGNOSTICAL SCREENING AND DETERMINATION OF ANTIOXIDANT ACTIVITY OF NELUMBO NUCIFERA GAERTN ETHANOL SEED EXTRACT BY DIFFERENT IN VITRO MODELS

Objective: To perform the pharmacognostical screening and determination of antioxidant activity of Nelumbo nucifera Gaertn ethanol seed extract by different in vitro models.Methods: The different pharmacognostical parameters were evaluated as per standard protocols with some modifications. The various concentrations of ethanol seed extract of Nelumbo nucifera were evaluated for antioxidant activity using the standard in vitro methods like hydrogen peroxide (H2O2) scavenging assay, nitric oxide (NO) radical scavenging assay, reducing power capacity assessment, β-Carotene bleaching assay, ferric thiocyanate method (FTC) and thiobarbituric acid (TBA) assay.Results: Extractive values, ash values and moisture content values of Nelumbo nucifera were found to be as per the IP 2007 and Ayurvedic pharmacopoeia standard. Among the four extracts viz. Petroleum ether, chloroform, ethanol and aqueous, the ethanol extract showed significant antioxidant activity. The ethanol seed extract of Nelumbo nucifera (NNSE) exhibited high antioxidant activity (IC50 = 12.65 µg/ml) in 1, 1-diphenyl-2-picryldydrazyl (DPPH) radical scavenging assay. In FTC method the absorbance of NNSE increased slowly, which shows strong antioxidant ability. The thin layer chromatography (TLC) of the extract revealed 6 spots with the Rf values 0.41, 0.47, 0.59, 0.65, 0.67, 0.74 with the solvent system of toluene: ethyl acetate: formic acid (5:4:0.5, v/v/v). The high-performance thin layer chromatography (HPTLC) revealed the spots at Rf values 0.65 and 0.68. These fractions obtained by preparative TLC also confirmed the same. Conclusion: The present investigation suggested that the NNSE has significant antioxidant activity. These results clearly indicate that Nelumbo nucifera is effective against free radical mediated diseases, thus replacing the synthetic ones.

Fabrication of Tamarindus indica seeds extract loaded-cream for photo-aged skin: Visioscan® studies.

IntroductionIntracellular and extracellular oxidative stress triggered by free radicals promotes skin aging, which is designated by atypical pigmentation and wrinkles. The consumption of antioxidants is an efficacious measure to avert symptoms involved in skin aging.AimThe current research was commenced to explore the anti-aging potential of antioxidants present in Tamarindus indica seeds extract.Material and methods Tamarindus indica seeds extract was obtained by concentrating the ethanolic extract of seeds. The antioxidant activities of the extract were measured by nitric oxide radical scavenging assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, hydroxyl radical scavenging assay and superoxide radical scavenging assay. Formulation comprising 4% of the concentrated extract of seeds was formulated by loading it in the internal aqueous phase of water-in-oil (W/O) cosmetic emulsion. The base, used as control, consisted of the same emulsion but without loading Tamarindus indica seeds extract. The cosmetic emulsions were applied to the cheeks of 11 healthy male volunteers for duration of 12 weeks. Both base and formulation were assessed for their antioxidant effects on different skin parameters i.e. skin moisture contents, elasticity and surface evaluation of living skin (SELS).ResultsThe formulation showed statistically significant (p ≤ 0.05) and the base showed insignificant (p > 0.05) effects on skin elasticity and skin moisture contents. There is a significant decline in SELS, skin scaliness (SEsc), skin wrinkles (SEw), skin smoothness (SEsm), and skin roughness (SEr) parameters after application of the formulation.ConclusionsTopical application of the cosmetic emulsion entrapped with Tamarindus indica seeds extract containing various antioxidants exerts potential skin antiaging effects.

Free Radical Scavenging Properties of Annona squamosa

Annona squamosa has extensively been used in the traditional and folkloric medicine and found to possess many biological activities. Different solvents, petroleum ether, chloroform, ethyl acetate and methanol extracts of Annona squamosa seeds (ASPE, ASCH, ASEA, ASME) have been used to prepare plant extracts. The present investigations dealt with the free radical scavenging activity of four extracts using various techniques such as total reducing power estimation, total phenolic count, 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging effect, evaluation of ABTS cation decolorisation capacity, FRAP assay, hdroxyl radical scavenging assay, super oxide assay and Nitric oxide radical scavenging assay of the extracts. The results showed that the four extracts of Annona squamosa showed significant reducing power in four extracts. The total phenolic contents in petroleum ether, chloroform, ethyl acetate, methanol extracts and positive control were 0.64±0.17, 0.54±0.27, 0.49±0.24, 0.57±0.22 and 0.66±0.33. The antioxidant capacity by ABTS assay of ASPE, ASCH, ASEA, ASME and positive control, trolox showed 77.75±0.5,73.25±1.7,78.5± 1.2, 80 ± 0.8 μg/ml and 94.2 ± 0.9 respectively. The (50 % scavenging activity) SA50 of ASPE and ASCH, ASEA and ASME was found to be 34.4 µg/ml, 43.8 µg/ml 34.7 µg/m and 28.8 µg/ml respectively by DPPH assay. The percentage of hydroxyl radical scavenging increased with the increasing concentration of the extracts. ASPE, ASCH, ASEA and ASME showed superoxide radical scavenging activity, as indicated by their values 66 ± 0.5, 68 ± 1, 63 ± 1 and 70 ± 0.5 μg/ml respectively compared to gallic acid which was 97 ± 0.5 μg/ml. The values for scavenging of nitric oxide for ASPE, ASCH, ASEA and ASME were 91.0 ± 1.0, 66.75 ± 0.5, 71.75 ± 1.1 and 75.75 ± 1.15 μg/ml while value for standard ascorbic acid was 91.0 ± 1.0 μg/ml. The results revealed strong antioxidants in four extracts may lead to the development of potent antioxidant agents from Annona squamosa seeds.

Therapeutic potentiality of Kedrostis foetidissima (Jacq.) Cogn., leaf extracts on free radicals induced oxidative damage in the biological system

Objectives: This study was convened to evaluate the free radical scavenging activity of Kedrostis foetidissima leaf extracts. Methods: The leaves of K. foetidissima (Jacq.) Cogn. were subjected to powder and extracted with various solvents such as water, methanol, acetone, chloroform, and petroleum ether. All the extracts were subjected to nitric oxide radical scavenging assay, hydrogen peroxide scavenging assay, superoxide anion radical scavenging assay, and egg yolk lipid peroxidation (LPO) assay. Results: All the extracts of K. foetidissima effectively reduced the generation of nitric oxide from sodium nitroprusside over a concentration of 2-10 mg/ml concentration which was significant at P < 0.05, showed moderate to potent level of H2O2 radical scavenging activity over the range of 2-10 mg/ml concentration, effectively reduced the superoxide anion radicals generated from phenazine metho-sulfate/nicotinamide adenine dinucleotide-nitroblue tetrazolium system over a concentration range of 2-10 mg/ml concentration, effectively inhibited the formation of LPO over a concentration range of 2-10 mg/ml. Conclusion: The results of this study indicated that among the five solvent extracts, the methanolic leaf extract have beneficial free radical scavenging activity and it also clearly suggested that the leaves may be used as a dietary supplement which can act as a natural antioxidant.

Potential anti-inflammatory, antioxidant and antimicrobial activities of Sambucus australis

Context: Sambucus australis Cham. & Schltdl. (Adoxaceae) is used in Brazilian folk medicine to treat inflammatory disorders.Objective: To evaluate the in vitro anti-inflammatory, antioxidant and antimicrobial properties of S. australis.Materials and methods: The anti-inflammatory activity of ethanol extracts of the leaf and bark of S. australis (1–100 μg/mL) were studied in lipopolysaccharide/interferon γ stimulated murine macrophages RAW 264.7 cells (24 h incubation) by investigating the release of nitric oxide (NO) and tumour necrosis factor-alpha (TNF-α) and in the TNF-α-induced nuclear factor kappa (NF-κB) assay. Minimum inhibitory concentration (MIC) was determined by the microdilution test (24 h incubation). Antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and the NO scavenging assays. Chemical composition was assessed by LC-MS/MS.Results: Antioxidant activities in the DPPH (IC50 43.5 and 66.2 μg/mL), FRAP (IC50 312.6 and 568.3 μg/mL) and NO radical scavenging assays (IC50 285.0 and 972.6 μg/mL) were observed in the leaf and bark ethanol extracts, respectively. Solely the leaf extract showed significant inhibition of NO and TNF-α production in RAW264.7 cells at concentrations of 2 and 100 μg/mL, respectively, and suppression of TNF-α inhibition of NF-κB by 12.8 and 20.4% at concentrations of 50 and 100 μg/mL, respectively. The extract also exhibited antibacterial activity against Salmonella typhimurium (MIC 250 μg/mL) and Klebsiella pneumoniae (MIC 250 μg/mL). LC-MS/MS revealed the presence of chlorogenic acid and rutin as major compounds.Discussion and conclusion: The results indicate that the ethanol leaf extract of S. australis exhibit prominent anti-inflammatory effects.

Antioxidant activity, phenolic-flavonoid content and high-performance liquid chromatography profiling of three different variants of Syzygium cumini seeds: A comparative study.

The medicinally important phytochemicals present in Syzygium cumini seeds probably accounts for its wide use in traditional systems of medicines in India, like Ayurveda, Unani, and Siddha. The aim of the study was to determine the antioxidant potential of three different geographical variants of S. cumini seeds and to compare the phenolic profiling to know the effect of geographical variation in phenolic composition. Total phenolic and flavonoid content of S. cumini seeds were analyzed. Antioxidant activities in terms of 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), nitric oxide and superoxide radical scavenging assays were performed. The most active fractions were subjected to high-performance liquid chromatography (HPLC) profiling to identify the phenolic composition. Among all the fractions, 70% methanol fraction of S. cumini seed showed significant antioxidant potential. There existed a linear correlation between phenolic content and antioxidant activity. HPLC profiling of 70% methanol (ME) fractions of all the variants revealed the presence of phenolic compounds with high concentrations of ellagic acid and gallic acid. The differences in phenolic concentration due to geographical changes might be the reason for higher antioxidant potential showed by 70% ME of Trivandrum variant. 70% methanolic fraction of S. cumini can act as a novel source of natural antioxidant.

Alkaloids in the valorization of European Lupinus spp. seeds crop

In this study, alkaloids from lupin varieties with commercial interest in Europe were identified and quantified. Additionally, the anti-inflammatory and antioxidant potential of some rich-alkaloid lupin extracts was assessed by 5-lipoxygenase (LOX) inhibition and nitric oxide radical (NO) scavenging assays, respectively. Relationships between extracts activity and those of pure standards were stablished.Nine alkaloids belonging to quinolizidine, indole and piperidine classes were identified by means of GC-IT/MS and quantified by GC-FID using a validated method. Lupanine was the most abundant alkaloid in white and narrow-leafed lupins (Lupinus albus L. and Lupinus angustifolius L., respectively) and sparteine in most yellow lupins (Lupinus luteus L.), but their proportions were cultivar-dependent. Gramine, smipine, angustifoline and lupanine derivatives were also identified. Five lupin varieties (Amiga, Estoril, Lumen, Dukat and Mister) were characterized as sweet (<0.5g alkaloids/kg, dry matter basis) and two of them respected the safety limit imposed by the European health authorities for human consumption (≤0.2g/kg, dry matter basis). Despite the weak effect on NO, a dose-dependent response towards LOX was found for all the studied extracts, which followed the order Taper>Estoril>Multitalia-PT>Dukat>Azuro>Multitalia-IT>Nacional.To our knowledge, the alkaloids composition of some of the varieties, as well as the study of the anti-inflammatory and antioxidant potential of rich-alkaloid lupin extracts are here reported for the first time. The results presented are a source of easily available data for producers, nutritionists and geneticists, and add biological knowledge on a major class of compounds in lupins.

COMPARATIVE ANALYSIS OF ANTIOXIDANT ACTIVITY AND PHYTOCHEMICAL CONTENTS IN ETHANOLIC LEAF EXTRACTS OF IN VITRO AND FIELD GROWN WITHANIA SOMNIFERA

ABSTRACTObjective: The present study was planned to compare antioxidant activity in vitro and field grown Withania somnifera was assessed using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and nitric oxide (NO) assays. Medicinal plants are a major source of phytochemicals used for the treatments ofhuman diseases. W. somnifera has anti-inflammatory, antioxidant, and antimicrobial properties.Methods: Antioxidant activity and phytochemical contents in W. somnifera were determined spectrophotometrically.Results: The results of antioxidant activity of field grown ethanolic leaf extract of W. somnifera showed maximum inhibition of 72.08% and 77.85%in DPPH (50 µg/ml) and NO (100 µg/ml) scavenging assays, respectively. Field grown ethanolic leaf extract of W. somnifera showed maximumconcentrations of phenolics, flavonoids, and carotenoids, as active phytochemicals, determined spectrophotometrically, which were found as676.5 µg/ml, 557.5 µg/ml, and 469 µg/ml, respectively, as compared to in vitro plant extracts.Conclusions: This study demonstrated that antioxidant activity and phytochemical contents of field grown ethanolic leaf extract of W. somnifera werefound to be comparatively higher than in vitro plant extracts. Leaf extracts of W. somnifera are a potential source of antioxidants and could preventmany free radical-related diseases.Keywords: Carotenoids content, 1-diphenyl-2-picrylhydrazyl scavenging assay, Flavonoids content, Nitric oxide radical scavenging assay, Phenoliccontent.

ANTI-RADICAL ACTIVITIES OF XANTHONES AND FLAVONOIDS FROM GARCINIA SCHOMBURGKIANA

&lt;p&gt;&lt;strong&gt;Objective: &lt;/strong&gt;The present study aimed to isolate and identify the phytochemical constituents of &lt;em&gt;Garcinia schomburgkiana&lt;/em&gt; branches and evaluate the antioxidant activity of the compounds.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Methods: &lt;/strong&gt;The chromatographic and spectroscopic (UV, IR, NMR and MS) techniques were used for the isolation and elucidation of the compounds, respectively. The antioxidant activity of the isolated compounds was examined through DPPH, ABTS, nitric oxide and hydroxyl radical scavenging assay.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Results: &lt;/strong&gt;The (&lt;strong&gt;-&lt;/strong&gt;)-5,7,3′,5′-tetrahydroxyflavanone (1), which was firstly found in the &lt;em&gt;Garcinia&lt;/em&gt; species, together with kaempferol (2), (-)-dihydrokaempferol (3), euxanthone (4), gentisein (5) and norathyriol (6) were isolated from &lt;em&gt;G. schomburgkiana&lt;/em&gt;. Among the isolated compounds, compound 1 and 6 exhibited the highest potential for anti-radical activities.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Conclusion: &lt;/strong&gt;Compound 1&lt;strong&gt; &lt;/strong&gt;could be used as the chemotaxonomic marker of &lt;em&gt;G. schomburgkiana&lt;/em&gt;. The branches of &lt;em&gt;G. schomburgkiana&lt;/em&gt; could be the alternative source of the antioxidants. The possible inhibitory mechanisms were proposed through the action of electron transfer, chelation, and nitrosylation.&lt;/p&gt;&lt;p&gt; &lt;/p&gt;

Comparison of In vitro Antioxidant Activity of Olmesartan and Amlodipine

International Journal of Pharmacology and Clinical Sciences,2015,4,4,90-93.DOI:10.5530/ijpcs.4.4.4Published:Dec 2015Type:Research ArticleAuthors:Rajathilagam Thiruvengadam, and Seethalakshmi Sankar Author(s) affiliations:Rajathilagam Thiruvengadam* Seethalakshmi Sankar Department of Pharmacology, ESIC Medical College, Chennai, TamilNadu, INDIA. Abstract:Introduction: Free radical oxidative stress has been implicated in the pathology of a wide variety of clinical disorders. Antioxidants are agents which scavenge the free radicals and prevent the damage caused by them. Angiotensin II receptor blockers used in the treatment of hypertension, have also been reported to protect organs such as kidney and heart. Althoug, the mechanisms of these protective effects are not fully understood, it is generally thought that their antioxidant effects likely play a role. Amlodipine, a calcium channel blocker, seems to exert atheroprotective effects through its antioxidant properties related to its chemical structure and independent of its calcium channel-blocking effect. Though research has proved that olmesartan and amlodipine exhibit antioxidant activity independent of their antihypertensive effects, there are not many in vitro studies to analyse which drug is a better antioxidant. Objective: This in vitro study was done to compare the antioxidant activity of olmesartan and amlodipine. Materials and Methods: In this study, we demonstrated the antioxidant activities of 10 mg/ml stock solutions of olmesartan and amlodipine in vitro. DPPH (1,1 Diphenyl 2-picryl hydrazide) and Nitric oxide free radical scavenging assays were done. Results: Olmesartan showed significant (49.48%) and consistent free radical scavenging activity by DPPH and Nitric oxide radical scavenging assays. Free radical scavenging activity of amlodipine was more significant (56.89%) than olmesartan but was inconsistent and non-concentration dependent. Conclusion: Hence this in vitro study has proved that olmesartan has better antioxidant activity than amlodipine. Keywords:Amlodipine, DPPH, Free radicals, Nitric Oxide, Olmesartan, Oxidative StressView:PDF (431.09 KB) PDFClick here to download the PDF file. Images Free radical scavenging activity by DPPH assay

Synthesis, Characterization of Novel Furan Based Imidazolones and Their Boilogical Studies

Background: Heterocyclic derivatives are of various pharmacological activities. The five membered rings, imidazole moiety is present in wide range of naturally occurring molecules, for example furan is a five membered heterocyclic nucleus which contain oxygen atom as heteroatom having broad spectrum of antimicrobial activities against microbes and fungal strains. Results: We prepared a series of 3-(4-Acetyl-phenyl)-5-arylidene-2-furan-2-yl-3, 5-dihydroimidazol- 4-one with different aldehydes through Erlenmeyer reaction and condensation methods. The newly synthesized compounds were characterized by IR, 1HNMR, 13C NMR and mass spectral studies. All final compounds are screened for their antimicrobial activities done by Gram-negative bacteria Proteus, Gram-positive bacteria Bacillus subtili and one yeast type fungi, C. albicans. Anti oxidant assay through DPPH radical scavenging, Nitric oxide assay. Conclusion: Furan based compounds having greater importance in medicinal chemistry. This research work is an attempt to highlight some compounds shows good potency against microbial activity. Of all the compounds 3d appear to be a potent molecule. 3a, 3c killed all micro organism and there by showing their non-specificity in recognising the micro organism. 3e appears to be less potent molecule as, it is not acting on Gram-negative bacteria’s and B. subtilis (Gram-positive) bacteria and it’s killing Micrococcus with MIC of 92 μg. Among all 3f compound shows good potent against DPPH and nitric oxide radical scavenging assay.

Chemical Composition and Antioxidant Activity of Essential Oil and Organic Extracts of Premna integrifolia Linn

This study was designed to examine the chemical composition and in vitro antioxidant activity of the hydrodistillated essential oil and various extracts obtained from Premna integrifolia Linn. GC-MS analysis of the essential oil was resulted in determination 29 different compounds, representing 95.73% of total oil. Antioxidant activities of the essential oil and organic extracts of chloroform, ethyl acetate and methanol were determined by three different test systems namely DPPH (2,2-diphenyl-1-picrylhydrazyl), superoxide and nitric oxide radical scavenging assays. The essential oil and methanol extract showed potent antioxidant activity among all the tested samples. Furthermore, the amount of total phenolic compounds was determined and its content in methanol extract was the highest as compared to other samples. The results indicate that the essential oil and extracts of Premna integrifolia could serve as an important bio-resource of antioxidants for using in the pharmaceutical industries.

Design, synthesis and biological evaluation of 1,3,4-oxadiazoles/thiadiazoles bearing pyrazole scaffold as antimicrobial and antioxidant candidates

A series of semicarbazones, thiosemicarbazones, 1,3,4-oxadiazoles/thiadiazoles bearing pyrazole scaffold were designed and synthesized. All the synthesized new compounds were characterized by 1H NMR, 13C NMR, MS and elemental analysis. The synthesized compounds were screened to probe their in vitro antimicrobial activity against bacteria and fungi species. The structure-activity relationship of the synthesized compounds was studied. The compounds displayed good to excellent potency against tested microorganisms. The in vitro antioxidant activities of the 1,3,4-oxadiazoles/thiadiazoles were evaluated by DPPH, hydroxyl and nitric oxide radical scavenging assay. Among the tested compounds, compound with chloro substitution showed good antioxidant potential.

Effect of pH during Extraction on the Antioxidant and Antiglycated Activities of Polysaccharides fromOpuntia Ficus Indica

The extraction of carbohydrates from Opuntia ficus indica cladodes at different pH was carried out by ultrasound followed by ethanol precipitation and dialysis. The extraction yields ranged from 4.6 to 24.5%. The highest content in galacturonic acid was observed for the acidic extract (37.4%). On high-performance size exclusion chromatography, the average molecular weight of all extracts ranged from 7,500,000 to 9,610,000 g/mol. The antioxidant activity of extracted polysaccharides was tested by three assays (1,1-diphenyl-2-picryl-hydrazil radical scavenging assay, Nitric oxide radical scavenging assay and Linoleic acid peroxidation). The glucose-induced advanced glycation end-product (AGE) formation of all extracts was also carried out using in vitro galactose–bovine serum albumin assay. Results showed that the acidic extract exhibited even better antioxidant capacity and inhibitory effect of AGE formation. Practical Applications Plant extracts containing polysaccharides are widely used in folk medicine for the treatment of skin and epithelium wounds and of mucous membrane irritation. In this case, polysaccharides extracted from Opuntia ficus indica cladodes, which is a plant native to South America and cultivated in dry regions as an important nutrient and food source, also are used in traditional medicine for their antiulcer and wound-healing effects. Thus, Opuntia ficus indica cladodes could be a natural candidate for research of herbal complement to the treatment of many diseases. The results found in this study reveal that the extraction under acidic conditions may enhance the antioxidant and antiglycated potential of polysaccharides extracted from Opuntia ficus indica cladodes.

벌꿀과 벌집채꿀의 페놀성분 및 항산화 효과 비교

본 연구에서는 야생화로부터 채밀한 제주 지역 벌꿀 및 벌집채꿀의 페놀성분 분석과 항산화 활성 비교평가를 시행하였다. 총 폴리페놀 및 플라보노이드 함량 측정 결과 물을 용매로 사용한 벌집채꿀에서 가장 높은 함량을 나타냈다. 또한 벌꿀 및 벌집채꿀 모두 농도 의존적으로 항산화 활성이 증가하는 양상을 보였으며, 이를 EC₅₀ 및 EC_0.5 값으로 환산한 결과 벌집채꿀이 벌꿀에 비해 통계적으로 유의하게 높은 항산화 활성을 나타내었다. 상기의 결과를 종합하여 봤을 때 총 폴리페놀 및 플라보노이드 함량과 항산화 활성간의 높은 연관성이 있다는 것을 추측 해볼 수 있었고 이를 상관관계를 통해 분석한 결과, 총 페놀 및 플라보노이드 성분의 함량과 항산화 활성이 통계적으로 유의한 상관관계를 나타냄을 확인할 수 있었다. 이러한 결과들은 잠재적 천연식품소재로의 벌집채꿀의 가능성을 시사하며 향후 이에 대한 체계적인 연구가 필요하다 사료된다. Although many studies have described the physiological effects of bee products, such as honey, propolis, pollen, and royal jelly, the health benefits of honeycomb remain incompletely characterized. We performed a comparative study of the antioxidant properties of honey and honeycomb extracts using two different solvents (water and 95% ethanol). The results showed that the total phenolic and flavonoid content of the honeycomb extract was higher than that of the honey extract. They also demonstrated that water was more effective than ethanol in extracting total phenols. The in vitro antioxidant properties of the water honeycomb extract were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO^&#x2022;) radical scavenging assays and ferrous ion chelating and reducing power assays. The antioxidant activity of the honeycomb extract exhibited was higher than that of the honey extract. The 50% effective concentrations (EC₅₀) of the honeycomb extract were 7.3&#xB1;0.26 mg/ml for scavenging DPPH radicals, 6.1&#xB1;0.22 mg/ml for scavenging NO^&#x2022; radicals, 6.9&#xB1;0.44 mg/ml for chelating ferrous ions, and 8.2&#xB1;0.11 mg/ml for reducing power. A correlation analysis revealed that the total phenolics and flavonoids of the honeycomb extract were the major contributors to the radical scavenging activity, ferrous ion chelating, and reducing power. The honeycomb extract was effective in protecting biological systems against various oxidative stresses in vitro. This is the first report on the antioxidant properties of honeycomb.

Fighting arboviral diseases: low toxicity on mammalian cells, dengue growth inhibition (in vitro), and mosquitocidal activity of Centroceras clavulatum-synthesized silver nanoparticles.

Dengue is a mosquito-borne viral disease that has rapidly spread in all regions of the world in recent years. Female mosquitoes, mainly Aedes aegypti, transmit dengue. Approximately 3,900 million people, in 128 countries, are at risk of dengue infection. Recently, a focus has been provided on the potential of green-synthesized nanoparticles as inhibitors of the production of dengue viral envelope (E) protein in Vero cells and downregulators of the expression of dengue viral E gene. Algae are an outstanding reservoir of novel compounds, which may help in the fight against mosquito-borne diseases. In this research, silver nanoparticles (AgNP) were rapidly synthesized using a cheap extract of the alga Centroceras clavulatum. AgNP were characterized by UV–vis spectrophotometry, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD). In mosquitocidal assays, LC50 values of C. clavulatum extract against A. aegypti larvae and pupae were 269.361 ppm (larva I), 309.698 ppm (larva II), 348.325 ppm (larva III), 387.637 ppm (larva IV), and 446.262 ppm (pupa). C. clavulatum extract also exhibited moderate antioxidant activity, both in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and nitric oxide (NO) radical scavenging assays. LC50 values of C. clavulatum-synthesized AgNP were 21.460 ppm (larva I), 23.579 ppm (larva II), 25.912 ppm (larva III), 29.155 ppm (larva IV), and 33.877 ppm (pupa). Furthermore, C. clavulatum-synthesized AgNP inhibited dengue (serotype dengue virus type-2 (DEN-2)) viral replication in Vero cells. Notably, 50 μg/ml of green-synthesized AgNP showed no cytotoxicity on Vero cells while reduced DEN-2 viral growth of more than 80%; 12.5 μg/ml inhibited viral growth of more than 50%. Cellular internalization assays highlighted that untreated infected cells showed high intensity of fluorescence emission, which denotes high level of viral internalization. Conversely, AgNP-treated infected cells showed reduced levels of fluorescence, failing to show significant viral load. Overall, our study showed that alga-mediated synthesis of metal nanoparticles may be considered to develop newer, safer, and cheap tools in the fight against the dengue virus, serotype DEN-2, and its vector A. aegypti, with little cytotoxicity on mammalian cells.

Antioxidant and cytotoxic activities of three species of tropical seaweeds.

BackgroundThree species of seaweeds (Padina tetrastromatica, Caulerpa racemosa and Turbinaria ornata) are widely consumed by Asians as nutraceutical food due to their antioxidant properties. Studies have shown that these seaweeds exhibit bioactivities which include antimicrobial, antiviral, anti-hypertensive and anticoagulant activities. However, investigations into the mechanisms of action pertaining to the cytotoxic activity of the seaweeds are limited. The aim of this study was to determine the antioxidant and cytotoxic activities of whole extracts of P. tetrastromatica, C. racemosa and T. ornata, including the cellular events leading to the apoptotic cell death of the extract treated-MCF-7 cells. Bioassay guided fractionation was carried out and the compounds identified.MethodsPowdered samples were sequentially extracted for 24 h. Their antioxidant activities were assessed by the DPPH radical, superoxide, nitric oxide and hydroxyl radical scavenging assays. The cytotoxic activity of the extract-treated MCF-7cells was assessed using the MTT assay. The most potent fraction was subjected to bioassay guided fractionation with column chromatography. All the fractions were tested for cytotoxic activity, caspase activity and effect on DNA fragmentation.ResultsAll three seaweeds showed potent radical scavenging activities in the various assays. The activity of the cellular antioxidant enzymes, superoxide dismutase, catalase and glutathione reductase, in MCF-7 cells, decreased in a time-dependent manner. The partially purified fractions exhibited higher cytotoxic activity, as assessed by the MTT assay, than the whole extracts in the breast adenocarcinoma cell line, MCF-7. LC-MS analysis revealed the presence of bioactive alkaloids such as camptothecin, lycodine and pesudopelletierine.ConclusionBased on the results obtained, all three seaweeds are rich sources of enzymatic and non-enzymatic antioxidants which could contribute to their reported medicinal benefits.

Phytochemicals of Salacia oblonga responsible for free radical scavenging and antiproliferative activity against breast cancer cell lines (MDA-MB-231).

Salacia oblonga, an inhabitant of tropical regions has been used in traditional Indian medicinal systems. Phytochemicals were extracted in methanol from the plant and analyzed for various biological activities. The results of biochemical tests for total phenolics (297±0.005 and 275±0.006) and flavonoids (95±0.004 and 61.6±0.004) in the aerial and root parts were indicated as Gallic acid and quercetin equivalents respectively. The Aerial and root extracts showed strong reducing ability based on reducing power and FRAP assays. The extracts exhibited significant IC50 values in DPPH, super oxide and nitric oxide radical scavenging assays. The extracts displayed low IC50 values (<50μg/ml) when assessed for antiproliferative activity against breast cancer cell lines using the MTT assay. GC-MS analysis of methanolic extracts have revealed the presence of compounds viz. n-Hexadecanoic acid, N-Methoxy-N-methylacetamide, Ursa-9(11), 12-dien-3-ol, Gamma-sitosterol etc., that might be potential candidates for the biological activity exhibited by the extract.