Search results for: DPPH free radical

Authors: Luís R. Silva, Ana C. Gonçalves, Catarina Bento, Fábio Jesus, Branca M. Silva

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Prunus avium Linnaeus, more known as sweet cherry, is one of the most appreciated fruit worldwide. Most of these quantities are produced in Fundão region, being Saco the cultivar most produced. Saco is very rich in bioactive compounds, especially phenolics, and presents great antioxidant capacity. The purpose of the present study was to investigate the chemical profile and biological potential, concerning antioxidant, anti-diabetic activity and protective effects towards erythrocytes by Saco sweet cherry collected from Fundão region (Portugal). The hydroethanolic extracts were prepared and passed through a C18 solid-phase extraction column. The phenolic profile analyzed by LC-DAD method allowed to the identification of 22 phenolic compounds, being 16 non-phenolics and 6 anthocyanins. In respect to non-coloured phenolics, 3-O-caffeoylquinic and ρ-coumaroylquinic acids were the main ones. Concerning to anthocyanins, cyanidin-3-O-rutinoside was found in higher amounts. Relatively to biological potential, Saco showed great antioxidant potential, through DPPH and NO radical assays, with IC50 =16.24 ± 0.46 µg/mL and IC50 = 176.69 ± 3.35 µg/mL for DPPH and NO, respectively. These results were similar to those obtained for ascorbic acid control (IC50 = 16.92 ± 0.69 and IC50 = 162.66 ± 1.31 μg/mL for DPPH and NO, respectively). In respect to antidiabetic potential, Saco revealed capacity to inhibit α-glucosidase in a dose-dependent manner (IC50 = 10.79 ± 0.40 µg/mL), being much active than positive control acarbose (IC50 = 306.66 ± 0.84 μg/mL). Additionally, Saco extracts revealed protective effects against ROO•-mediated toxicity generated by AAPH in human blood erythrocytes, inhibiting hemoglobin oxidation (IC50 = 38.57 ± 0.96 μg/mL) and hemolysis (IC50 = 73.03 ± 1.48 μg/mL), in a concentration-dependent manner. However, Saco extracts were less effective than quercetin control (IC50 = 3.10 μg/mL and IC50 = 0.7 μg/mL for inhibition of hemoglobin oxidation and hemolysis, respectively). The results obtained showed that Saco is an excellent source of phenolic compounds. These ones are natural antioxidant substances, which easily capture reactive species. This work presents new insights regarding sweet cherry antioxidant properties which may be useful for the future development of new therapeutic strategies for preventing or attenuating oxidative-related disorders.

Keywords: antioxidant capacity, health benefits, phenolic compounds, saco

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Authors: K. Fellah, H. Benmehdi, A. Amrouche, H. Malainine, F. Memmou, H. Dalile, W. Siata

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This work aims to evaluate the antioxidant of flavonoids extracted from the leaves of Prunus persica L. A phytochemical screening allowed us to highlight the different phytochemicals present in the leaves of the studied plant. The selective extraction of flavonoids gave yields of 0.71, 1.5, and 4.8% for the fractions ethyl ether, ethyl acetate and n- butanol, respectively. The reading of the antioxidant activity of different extracts of flavonoids by HPLTC method revealed positive reaction (yellow spots) on the TLC plates sprayed with DPPH. Using the DPPH method, the fractions of flavonoids (bunanol, ethyl acetate and Diethyl ether) showed a potent scavenging activity with IC50 = 0.22; 0.27 and 0.76 mg / ml, respectively. Furthermore, our findings revealed the extracts under study exhibited higher reducing potential which depends upon extract concentration. These results obtained from this investigation confirm that the Prunus persica remains a major resource of bioactive molecules.

Keywords: Prunus persica L., phytochemical study, flavonoids, antioxidant activity, TLC bioautographic, FRAP, DPPH

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Authors: Hassina Harkat, Samiha Taybe, Salima Loucif, Valérie Beneteau, Patrick Pale

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Indole and its derivatives have attracted great interest because of their importance in the synthetic organic and medicinal chemistry. They are widely used as anti hypertension, anti tubercular, anticancer activity, antiviral, Alzheimer's disease, antioxidant properties, and free radical induced lipid peroxidation. Many drugs and natural products contain indole moiety, such as the vinca alkaloids, fungal metabolites and marine natural products. Generally applicable synthetic methods for indole moiety involve ring closure to form the pyrrole. Indole derivatives can also be accessed by further functionalization of the indole nucleus. Therefore we report a mild and efficient protocol for the synthesis of analogues of indole catalyzed via zeolithe USY doped with CuI under solvent-free conditions.

Keywords: indole, zeolithe, USY-CuI, heterogeneous catalysis

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Authors: Dalvir Kataria, Khushminder Kaur Chahal, Amit Kumar

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The carrot seed essential oil was obtained by hydrodistillation. Hexane, dichloromethane, and methanol solvents were used for extraction of carrot seed by Soxhlet extraction methods. The major and minor compounds identified in carrot seed essential oil were carotol (52.73), daucol (5.10), daucene (5.68), (E)-β-farnesene (5.40), β-cubebene (3.19), longifolenaldehyde (3.23), β-elimene (3.23), (E)-caryophyllene (1.22), β-bisabolene (2.95) etc. The chemical composition of hexane, dichloromethane, and methanol extracts was different. Carotol was the common compound present. Major compounds isolated were from the carrot seed essential oil by column chromatography. Chemical transformations of carotol (2) with mercuric acetate/sodium borohydride, dry hydrochloric acid gas, acetonitrile/sulfuric acid, selenium dioxide/t-butyl hydrogen peroxide, N-bromosuccinimide, hydrogen iodide, and phenol were carried out. The derivatives of carotol were designed to explore the significance of some structural modifications in relation to antioxidant activities. The structures of major compounds and derivatives were confirmed on the basis of FT-IR, 1HNMR and 13CNMR spectroscopy. Antioxidant activity of carrot seed essential oil, various extracts and isolated compounds were tested by in vitro models involving 2, 2-diphenyl-1-picrylhydrazyl (DPPH•), hydroxyl (OH•), nitric oxide (NO•), superoxide radical scavenging methods and ferric reducing antioxidant power assay (FRAP). Chemical transformations of major isolated compound carotol were carried out, and antioxidant activity of all compounds was undertaken. The major sesquiterpenoidcarotol isolated from carrot seed essential oil showed the highest antioxidant activity in all the methods. The methanol extract showed higher antioxidant potential as compared to carrot seed essential oil, hexane, and dichloromethane extracts.

Keywords: antioxidant, carotol, carrot, DPPH

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Authors: Borokini Funmilayo Boede

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B. alba L., commonly called ‘Amunututu’ and Solanecio biafrae called ‘Worowo’ among the Yoruba tribe in the southwest part of Nigeria are reported to be of great ethnomedicinal importance but are among many underutilized green leafy vegetables in the country. Many studies have established the nutritional values of these vegetables, utilization are very poor and indepth information on their chemical profiles is scarce. The aqueous, methanolic and ethanolic extracts of these vegetables were subjected to phytochemical screening and phenolic profiles of the alcoholic extracts were characterized by using high-performance liquid chromatography coupled with diode array detector (HPLC-DAD). Total phenol and flavonoid contents were determined, antioxidant activities were evaluated using five in vitro assays to assess DPPH, nitric oxide and hydroxyl radical-scavenging abilities, as well as reducing power with ferric reducing antioxidant assay and phosphomolybdate method. The antibacterial activities of the extracts against Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella typhi were evaluated by using agar well diffusion method and the antifungal activity evaluated against food-associated filamentous fungi by using poisoned food technique with the aim of assessing their nutraceutical potentials to encourage their production and utilization. The results revealed the presence of saponnin, steroids, tannin, terpenoid and flavonoid as well as phenolic compounds: gallic acid, chlorogenic acid, caffeic acid, coumarin, rutin, quercitrin, quercetin and kaemferol. The vegetables showed varying concentration dependent reducing and radical scavenging abilities from weak to strong compared with gallic acid, rutin, trolox and ascorbic acid used as positive controls; the aqueous extracts which gave higher concentrations of total phenol displayed higher ability to reduce Fe (lll) to Fe (ll) and stronger inhibiting power against hydroxyl radical than the alcoholic extracts and in most cases exhibited more potency than the ascorbic acids used as positive controls, at the same concentrations, whereas, methanol and / or ethanol extracts were found to be more effective in scavenging 2, 2-diphenyl-1-picryl hydrazyl radical and showed higher ability to reduce Mo (VI) to Mo (V) in total antioxidant assay than the aqueous extracts. However, the inhibition abilities of all the extracts against nitric oxide were comparable with the ascorbic acid control at the same concentrations. There were strong positive correlations with total phenol (mg GAE/g) and total flavonoid (mg RE/g) contents in the range TFC (r=0.857- 0999 and r= 0.904-1.000) and TPC (r= 0.844- 0.992 and r= 0.900 -0.999) for Basella alba and Senecio biafrae respectively. Inhibition concentration at 50 % (IC50) for each extract to scavenge DPPH, OH and NO radicals ranged from 32.73 to 1.52 compared with control (0.846 - -6.42) mg/ml. At 0.05g/ml, the vegetables were found to exhibit mild antibacterial activities against Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi compared with streptomycin sulphate used as control but appreciable antifungi activities against (Trichoderma rubrum and Aspergillus fumigates) compared with bonlate antibiotic positive control. The vegetables possess appreciable antioxidant and antimicrobial properties for promoting good health, their cultivation and utilization should be encouraged especially in the face of increasing health and economic challenges and food insecurity in many parts of the world.

Keywords: antimicrobial, antioxidants, extracts, phytochemicals

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Authors: Elene Tatunashvili, Bun Chan, Philippe E. Nashar, Christopher S. P. McErlean

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The reduction of aryl diazonium salts is one of the most efficient ways to generate aryl radicals for use in a wide range of transformations, including Sandmeyer-type reactions, Meerwein arylations of olefins and Gomberg-Bachmann-Hey arylations of heteroaromatic systems. The aryl diazonium species can be reduced electrochemically, by UV irradiation, inner-sphere and outer-sphere single electron transfer processes (SET) from metal salts, SET from photo-excited organic catalysts or fragmentation of adducts with weak bases (acetate, hydroxide, etc.). This paper details an approach for the metal-free reduction of aryl diazonium salts, which facilitates the efficient synthesis of various aromatic compounds under exceedingly mild reaction conditions. By measuring the oxidation potential of a number of organic molecules, a series of nucleophiles were identified that reduce aryl diazonium salts via the addition-fragmentation mechanism. This approach leads to unprecedented operational simplicity: The reactions are very rapid and proceed in the open air; there is no need for external irradiation or heating, and the process is compatible with a large number of radical reactions. We illustrate these advantages by using the addition-fragmentation strategy to regioselectively arylate a series of heterocyclic compounds, to synthesize ketones by arylation of silyl enol ethers, and to synthesize benzothiophene and phenanthrene derivatives by radical annulation reactions.

Keywords: diazonium salts, hantzsch esters, oxygen, radical reactions, synthetic methods

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Authors: L. Bidyalakshmi, R. Ananthan, T. Longvah

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Antioxidants are substances that can prevent or delay oxidative damage of lipids, proteins and nucleic acids by reactive oxygen species. These help in lowering incidence of degenerative diseases such as cancer, arthritis, atherosclerosis, heart disease, inflammation, brain dysfunction and acceleration of the ageing process. The north eastern part of India falls among the global hotspots of biodiversity. Over the years, the local communities in the region have developed ingenious uses of many wild plants within their environment as food sources. Many of these less familiar foods form an integral part of the diet of these communities, and some are traditionally valued for its therapeutic effects. So the study was carried to estimate the antioxidant activity of some of these indigenous foods. Twenty-eight indigenous plant foods were studied for their antioxidant activity. Antioxidant activities were determined by using DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay, FRAP (Ferric Reducing Antioxidant Power) assay and SOSA (Super Oxide Scavenging Assay). Out of the twenty-eight plant foods, there were thirteen leafy vegetables, four fruits, five roots and tubers, four spices and two mushrooms. Water extract and methanol extract of the samples were used for the analysis. The leafy vegetable samples exhibited antioxidant capacity with IC50 ranging from 8-1414 mg/ml for lipid extract and 34-37878 mg/ml for aqueous extract in DPPH assay. Total FRAP value ranging from 58-1005 mmol FeSO4 Eq/100g of the sample, which is comparatively higher than the antioxidant capacity of some commonly consumed leafy vegetables. In SOSA, water extract of leafy vegetables show a range of 0.05-193.68 µmol ascorbic acid equivalent/g of the samples. While the methanol extract of the samples show 0.20-21.94 µmol Trolox equivalent/g of the samples. Polygonum barbatum, Wendlandia glabrata and Polygonum posumbu have higher antioxidant activity among the leafy vegetables analysed. Among the fruits, Rhus hookerii showed the highest antioxidant activities in both FRAP and SOSA methods while Spondias magnifera exhibited higher antioxidant activity in DPPH method. Alocasia cucullata exhibited higher antioxidant activity in DPPH and FRAP assays while Alpinia galanga showed higher antioxidant activity in SOSA assay when compared to the other samples of roots and tubers. Elsholtzia communis showed high antioxidant activity in all the three parameters among the spices. For the mushrooms, Pleurotus ostreatus exhibited higher antioxidant activity than Auricularia delicate in DPPH and SOSA. The samples analysed exhibited antioxidant activity at varying levels and some exhibited higher antioxidant activity than the commonly consumed foods. So consumption of these less familiar foods may play a role in preventing human disease in which free radicals are involved. Further studies on these food samples on phytonutrients and its contribution to the antioxidant activities are required.

Keywords: antioxidant activity, DPPH, FRAP, SOSA

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Authors: Esma Hande Alıcı, Gülnur Arabacı

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Antioxidants are compounds or systems that can safely interact with free radicals and terminate the chain reaction before vital molecules are damaged. The anti-oxidative effectiveness of these compounds depends on their chemical characteristics and physical location within a food (proximity to membrane phospholipids, emulsion interfaces, or in the aqueous phase). Antioxidants (e.g., flavonoids, phenolic acids, tannins, vitamin C, vitamin E) have diverse biological properties, such as antiinflammatory, anti-carcinogenic and anti-atherosclerotic effects, reduce the incidence of coronary diseases and contribute to the maintenance of gut health by the modulation of the gut microbial balance. Plants are excellent sources of antioxidants especially with their high content of phenolic compounds. Raphanus raphanistrum L., the wild radish, is a flowering plant in the family Brassicaceae. It grows in Asia and Mediterranean region. It has been introduced into most parts of the world. It spreads rapidly, and is often found growing on roadsides or in other places where the ground has been disturbed. It is an edible plant, in Turkey its fresh aerial parts are mostly consumed as a salad with olive oil and lemon juice after boiled. The leaves of the plant are also used as anti-rheumatic in traditional medicine. In this study, we determined the antioxidant capacity of two different solvent fractions (methanol and ethyl acetate) obtained from Raphanus raphanistrum L. plant leaves. Antioxidant capacity of the plant was introduced by using three different methods: DPPH radical scavenging activity, CUPRAC (Cupric Ion Reducing Antioxidant Capacity) activity and Reducing power activity.

Keywords: antioxidant activity, antioxidant capacity, Raphanis raphanistrum L., wild radish

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Authors: Tom Turner

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The recent financial crisis in 2008 and the growing inequality in developed industrial societies would appear to present significant challenges to capitalism and the free market. Yet there have been few substantial mainstream political or economic challenges to the dominant capitalist and market paradigm to-date. There is no dearth of critical and theoretical (academic) analyses regarding the prevailing systems failures. Yet despite the growing inequality in the developed industrial societies and the financial crisis in 2008 few commentators have advocated the comprehensive socialization or state ownership of the means of production to our knowledge – a core principle of radical Marxism in the 19th and early part of the 20th century. Undoubtedly the experience in the Soviet Union and satellite countries in the 20th century has cast a dark shadow over the notion of centrally controlled economies and state ownership of the means of production. In this paper, we explore the history of a doctrine advocating the socialization or state ownership of the means of production that was central to Marxism and socialism generally. Indeed this doctrine provoked an intense and often acrimonious debate especially for left-wing parties throughout the 20th century. The debate within the political economy tradition has historically tended to divide into a radical and a revisionist approach to changing or reforming capitalism. The radical perspective views the conflict of interest between capital and labor as a persistent and insoluble feature of a capitalist society and advocates the public or state ownership of the means of production. Alternatively, the revisionist perspective focuses on issues of distribution rather than production and emphasizes the possibility of compromise between capital and labor in capitalist societies. Over the 20th century, the radical perspective has faded and even the social democratic revisionist tradition has declined in recent years. We conclude with the major challenges that confront both the radical and revisionist perspectives in the development of viable policy agendas in mature developed democratic societies. Additionally, we consider whether state ownership of the means of production still has relevance in the 21st century and to what extent state ownership is off the agenda as a political issue in the political mainstream in developed industrial societies. A central argument in the paper is that state ownership of the means of production is unlikely to feature as either a practical or theoretical solution to the problems of capitalism post the financial crisis among mainstream political parties of the left. Although the focus here is solely on the shifting views of the radical and revisionist socialist perspectives in the western European tradition the analysis has relevance for the wider socialist movement.

Keywords: sate ownership, ownership means of production, radicals, revisionists

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Authors: Florian Wohlfeil, Orestis Terzidis, Louisa Hellmann

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Radical technological innovations enable companies to reach strong market positions and are thus desirable. On the other hand, the innovation process is related to significant costs and risks. Hence, the knowledge of the factors that influence success is crucial for technology driven companies. In a previous study, we have developed a conceptual framework of 25 Critical Success Factors for radical technological innovations and mapped them to four main categories: Technology, Organization, Market, and Process. We refer to it as the Technology-Organization-Market-Process (TOMP) framework. Taking the TOMP framework as a reference model, we conducted a structured and focused literature review of eleven standard books on the topic of radical technological innovation. With this approach, we aim to evaluate, expand, and clarify the set of Critical Success Factors detailed in the TOMP framework. Overall, the set of factors and their allocation to the main categories of the TOMP framework could be confirmed. However, the factor organizational home is not emphasized and discussed in most of the reviewed literature. On the other hand, an additional factor that has not been part of the TOMP framework is described to be important – strategy fit. Furthermore, the factors strategic alliances and platform strategy appear in the literature but in a different context compared to the reference model.

Keywords: Critical Success Factors, radical technological innovation, TOMP framework, innovation process

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Authors: Pornrut Rabintossaporn, Suphaket Saenthaweesuk, Amornnat Thuppia, Nuntiya Somparn

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Several dietary and herbal plants have been shown to possess cytoprotective and antioxidant effects with various mechanisms of action. The aim of this study was to determine the antioxidant effects and its mechanism of aqueous leaves extract of Ocimum americanum (OA), commonly known as American basil or 'hoary basil', in rat. The extract was screened for its phytochemical contents and antioxidant activity in vitro. Moreover, the extract was studied in rats to evaluate its effects in vivo. Rats were orally administered with the extract at the dose of 100, 200 and 400 mg/kg for 28 days. Phytochemical screening of plant extracts revealed the presence of alkaloid, cardiac glycosides, tannin and steroid compounds. The extract contained phenolic compounds 36.91 ± 0.66 mg of gallic acid equivalents per gram OA extract. The free radical scavenging activity assessed by DPPH assay gave IC50 of 41.27 ± 1.86 µg/mL, which is relatively lower than that of BHT with IC50 of 12.34 ± 1.14µg/mL. In the animals, the extract was well tolerated by the animals throughout the 28 days of study as shown by normal serum levels AST, ALP, ALT, BUN and Cr as well as normal histology of liver and pancreatic and kidney tissue. The protein expression of antioxidant enzymes, γ-glutamylcysteine ligase (γ-GCL) in liver was significantly increased compared with normal control. Consistent with the induction of γ-GCL protein expression significantly reduction of serum oxidative stress marker malondialdehyde (MDA) was found in rat treated with OA extract compared with control. Taken together, this study provides evidence that Ocimum americanum exhibits direct antioxidant properties and can induce cytoprotective enzyme in vivo.

Keywords: antioxidant, γ-glutamylcysteine ligase, MDA, Ocimum americanum

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Authors: Jamilu Adamu

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Radical political activities among the people of Northern Nigeria and Sabon Birni, in particular from the formation of the Northern Element Progressive Union (NEPU) and Northern People Congress (NPC) in the last decade of colonial rule, led to the dramatic spread of radical ideas that were expressed through party politics. The above two parties were said to be more prominent in each of the movements throughout the period covered by this study. The NEPU and NPC were said to have opposed one another in an attempt to establish their political control in the area. What is apparent about the nature of the opposition is that the earlier NEPU and People Redemption Party (PRP) emerged from the idea of liberating the common man (Talakawa) against all forms of oppression, thereby rejecting a contrary idea of supporting the native elites and their colonial collaborators as envisaged in the ideology of the later NPC and National Party of Nigeria (NPN). This laid the ground for ideological confrontation between the supporters of the two opposing wings all over the northern emirates and the Sabon Birni district in particular. The study used a qualitative method of data collection. This study examines the historical developments of radical party politics among the Gobirawa people of the Sabon Birni District of Sokoto. It also investigates the factors that inspired opposition politics among the Gobirawa people of Sabon Birni. These were analyses side-by-side with the role of the traditional leaders in the area in suppressing the activities of the opposition party.

Keywords: NEPU, NPC, radical politics, Sabon-Birni District

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Authors: Strahinja Kovacevic, Milica Karadzic Banjac, Jasmina Vitas, Stefan Vukmanovic, Radomir Malbasa, Lidija Jevric, Sanja Podunavac-Kuzmanovic

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The present study deals with chemometric regression analysis of quality parameters and the radical scavenging ability of kombucha fermented kefir-like products obtained with winter savory (WS), peppermint (P), stinging nettle (SN) and wild thyme tea (WT) kombucha inoculums. Each analyzed sample was described by milk fat content (MF, %), total unsaturated fatty acids content (TUFA, %), monounsaturated fatty acids content (MUFA, %), polyunsaturated fatty acids content (PUFA, %), the ability of free radicals scavenging (RSA Dₚₚₕ, % and RSA.ₒₕ, %) and pH values measured after each hour from the start until the end of fermentation. The aim of the conducted regression analysis was to establish chemometric models which can predict the radical scavenging ability (RSA Dₚₚₕ, % and RSA.ₒₕ, %) of the samples by correlating it with the MF, TUFA, MUFA, PUFA and the pH value at the beginning, in the middle and at the end of fermentation process which lasted between 11 and 17 hours, until pH value of 4.5 was reached. The analysis was carried out applying univariate linear (ULR) and multiple linear regression (MLR) methods on the raw data and the data standardized by the min-max normalization method. The obtained models were characterized by very limited prediction power (poor cross-validation parameters) and weak statistical characteristics. Based on the conducted analysis it can be concluded that the resulting radical scavenging ability cannot be precisely predicted only on the basis of MF, TUFA, MUFA, PUFA content, and pH values, however, other quality parameters should be considered and included in the further modeling. This study is based upon work from project: Kombucha beverages production using alternative substrates from the territory of the Autonomous Province of Vojvodina, 142-451-2400/2019-03, supported by Provincial Secretariat for Higher Education and Scientific Research of AP Vojvodina.

Keywords: chemometrics, regression analysis, kombucha, quality control

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Authors: Abdelouahab Dehimati, Fatiha Bedjou

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This study focused on the antioxidant and antimicrobial activity of four extracts from the plant Matricaria pubscens (Asteraceae) harvest in the region of Ghardaia, the northern Sahara of Algeria. The different extracts were analyzed for their content of phenolic compounds and their biological activities. The ethanol extract expresses a better extraction yield (44.22%). We have first performed the quantitative colorimetric methods for total polyphenols. Wherein the aqueous extract shows the highest total polyphenol content and total flavonoid (216.66±2.58 mg Eq GA/g and 111.04±0.49 mg Eq Q/g E, respectively) and ethanol extract 50% total tannins content (68.88±2.72 mg Eq AT/g E). The evaluation of the antioxidant activity of extracts of Matricaria pubscens by the arbitrary value IC50. The ethanol 50% extract is expressed strong activity with an IC50 14.19±1.25 mg/m against the DPPH radical and 11.66±0.53 mg/ml against the ABTS radical). In addition, the aqueous extract showed strong reducing power with an IC50 (48.61±1.14 mg/ml). However, the results obtained by the reducing power of phosphomolybdat the test are calculated by the iron maximum absorbance where ethanol extract 50% gives an absorbance of about 1.641 ± 0.01nm. Otherwise, methanol 70% and butanol 80% extracts gave a very large chelating effect of iron with an IC50 (38.38±0.01 μg/ml and 38.58±0.04 μg/ml respectively). By the method of disc Diffuson, the results of the antimicrobial activity are achieved butanolic extract 80% shows high activity towards MRSA (MIC: 3.51mg/ml; BMC>100 mg/ml). Their shares, the extracts were the most active for the antifungal test, the butanol 80% extract was the most active against A. niger (MIC: 12.5 mg/ml; FMC>100 mg/ml). These preliminary results could be used to justify the traditional use of this plant and their phenolic compounds could be exploited for therapeutic purposes, such as antioxidants and antimicrobial effects.

Keywords: Matricaria pubscens, phenolic compounds, antioxidant activity, antimicrobial activity, IC50, MIC

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Authors: Kaida Kobylka

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Museum education policy can be developed through the lens of radical democracy and radically democratic relational aesthetics to provoke a more wholistic, agonistic, and utopian educational experiences that expand a viewer’s experiences and knowledge of artwork in a museum’s permanent collection to encourage a deeper understanding of art and the community of a museum’s connections to equity, diversity, inclusion, and decolonization. Practices used by the museum will create cohesive and engaging informal education that utilizes community-based, alternative knowledge and create dignity-safe spaces for viewers to engage critically with the visual objects.

Keywords: museum education, radical democracy, Canadian policy, community-based knowledge

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Authors: Dhivya Arumugam, Kaliyappan Thananjeyan

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The monomer of (3-((4-(methacryloyloxy)phenylimino)methyl)-2-hydroxybenzoic acid) schiff base polymer was prepared by reacting methacryloyl chloride with imine compound derived from 3-formylsalisylic acid and 4- aminophenol. The monomer was polymerized in DMF at 70oC using benzoyl peroxide as free radical initiator. Polymer metal complex was obtained in DMF solution of polymer with aqueous solution of metal ions. The polymer and the polymer metal complex were characterized by elemental analysis and spectral studies. The elemental analysis data suggest that the metal to ligand ratio is 1:1 and hence, it acts as a binucleating compartmental ligand. The IR spectral data of these complexes suggest that the metals are coordinated through nitrogen of the imine group, the oxygen of carboxylate ion and the oxygen of the phenolic –OH group which also acts as the bridging ligand. The electronic spectra and magnetic moments of the polychelates shows that octahedral and square planar structure for Ni(II) and Cu(II) complexes respectively. X-ray diffraction studies revealed that polychelates are highly crystalline. The thermal and electrical properties, catalytic activity, structure property relationships are discussed. Further the synthesized polymer was used for metal uptake studies from waste water, which is one of the effective waste water treatment strategies. And also, the polymers and polychelates were investigated for antimicrobial activity with various microorganisms by using agar well diffusion method and the results have been discussed.

Keywords: acyclic compartmental ligands, binucleating ligand, 3-formylsalicylic acid, free radical polymerization, polluting ions, polychelate

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Authors: Richard I. Licayan, Aisle Janne B. Dagpin, Romeo M. Del Rosario, Nenita D. Palmes

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Hiptage benghalensis, Antigonon leptopus, Macroptillium atropurpureum, and Dioscorea bulbifera L. are herbal weeds that have been used by traditional healers in rural communities in the Philippines as medicine. In this study, the basic pharmacological components of the crude secondary metabolites extracted from the four herbal weeds and their in vitro antioxidant properties was investigated to provide baseline data for the possible development of these metabolites in pharmaceutical products. Qualitative screening of the secondary metabolites showed that alkaloids, tannins, saponins, steroids, and flavonoids were present in their leaf extracts. All of the plant extracts showed varied antioxidant activity. The greatest DPPH radical scavenging activity was observed in H. begnhalensis (84.64%), followed by A. leptopus (68.21%), M. atropurpureum (26.62%), and D. bulbifera L. (19.04%). The FRAP assay revealed that H. benghalensis had the highest antioxidant activity (8.32 mg/g) while ABTS assay showed that M. atropurpureum had the strongest scavenging ability of free radicals (0.0842 mg Trolox/g). The total flavonoid content (TFC) analysis showed that D. bulbifera L. had the highest TFC (420.35 mg quercetin per gram-dried material). The total phenolic content (TPC) of the four herbal weeds showed large variations, between 26.56±0.160 and 55.91±0.087 mg GAE/g dried material. The plant leaf extracts arranged in increasing values of TPC are H. benghalensis (26.565) < A. leptopus (37.29) < D. bulbifera L. (46.81) < M. atropurpureum (55.91). The obtained results may support their use in herbal medicine and as baseline data for the development of new drugs and standardized phytomedicines.

Keywords: antioxidant properties, total flavonoids, total phenolics, creeping herbal weeds

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Authors: Sharon N. Nuñal, May Flor S. Muegue, Nizzy Hope N. Cartago, Raymund B. Parcon, Sheina B. Logronio

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The antioxidant and anti-inflammatory potentials of Perna Viridis, Modiolus philippinarum, and Mytella charruana found in the Philippines were assessed. Mussel protein samples were hydrolyzed using trypsin, maturase, alcalase and pepsin at 1% and 2% concentrations and then fractionated through membrane filtration (<10 kDa and <30 kDa). Antioxidant assays showed that pepsin hydrolysate at 2% enzyme concentration exhibited the maximum activities for both 2,2-Diphenyl-1-picrylhydrazyl (DPPH) Radical Scavenging Activity (155-176 µM TE/mg protein) and 2,2-azinobis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging (67-68 µM TE/mg protein) assays while trypsin hydrolysate dominated the Ferric Reducing Antioxidant Power (FRAP) for the three mussel species. Lower molecular weight peptide fractions at <10 kDa exhibited better antioxidant activities than the higher molecular weight fractions. The anti-inflammatory activities of M. philippinarum and M. charruana showed comparable protein denaturation inhibition potentials with the highest in P. Viridis samples (98.93%). The 5-Lipoxygenase (5-LOX) inhibitory activities of mussel samples showed no significant difference with inhibition exceeding 70%. P. Viridis demonstrated the highest inhibition against Cyclooxygenase-2 (COX-2) at 56.19%, while the rest showed comparable activities. This study showed that the three mussel species are potential sources of bioactive peptides and lipids with antioxidant and anti-inflammatory properties.

Keywords: anti-inflammatory, antioxidant, bioactive properties, mussel

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Authors: Kandi Sridhar, Charles Albert Linton

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Grapes are excellent sources of bioactive compounds, which have been suggested to be responsible for lowering the risk of chronic diseases. Fresh and freeze-dried extracts of Kyoho and Jubilee, commercial grape varieties available in Taiwan and attractive for their quality berries, were investigated for their total phenolics and total flavonoids contents and related dose-dependent antioxidants properties using various in vitro assays. The efficiency of the extraction yield ranged from 7.10 % to 25.53 % (w/w), depending on solvent used. Fresh samples of Kyoho and Jubilee exhibited total polyphenolic contents (351.56 ± 23.08 and 328.67 ± 16.54 µg GAE/mL, respectively), whereas Kyoho freeze-dried methanol: water extracts contains the good levels of total flavonoids (4767.82 ± 22.20 µg QE/mL). Kyoho and Jubilee freeze-dried extracts exhibited the highest total flavonoid contents. There was a weak correlation between total phenolic and flavonoid assays (r= -0.05, R2 = 0.02, p > 0.05). Kyoho fresh and freeze-dried samples showed the DPPH (11.51 – 77.82 %), superoxide scavenging activity (33.61 – 81.95 %), and total antioxidant inhibition (92.01 – 99.28 %), respectively. Total flavonoids were statistically correlated with EC50 DPPH scavenging radicals (r =0.91, p < 0.01), EC50 nitric oxide (r = 0.25, p > 0.05), and EC50 lipid peroxidation radicals (r = 0.38, p > 0.05). These results suggested that the two commercial grape cultivars in Taiwan could be used as a good source of natural antioxidants. Thus, consumption of grapes as a source antioxidant might lower the risk of chronic diseases. Moreover, future studies will investigate and develop phenolic acid profile for the cultivars in Taiwan.

Keywords: antioxidants, EC50 radical scavenging activity, grape cultivars, total phenolics

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Authors: Dian Muzdalifah, Anastasia F. Devi, Zatil A. Athaillah, Linar Z. Udin

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Tempe is a functional food prepared from soybeans through Rhizopus spp fermentation. It is well known as functional food, originated from Indonesia. Most studies on tempe functionalities refer to ripe (48 h fermentation) tempe and only limited studies discuss overripe tempe while longer fermentation time possibly increased tempe health benefit. Hence, the present study was performed to investigate the cytotoxic activity againts MCF-7 breast cancer cells and antioxidant property of tempe prepared from 0–156 h of fermentation. Tempe samples were dried and extracted with acetone and ethanol, respectively. Their extracts were used for subsequent analysis. The cytotoxic activity was assessed on MCF 7 breast cancer cells using Alamar Blue method. The antioxidant activity was determined by DPPH free radical scavenging assay. The results indicated that acetone extracts of 108 h tempe had a potent cytotoxic activity against MCF-7 breast cancer cells (IC50 = 2.54 ± 0,30 μg/mL). Ethanol extracts of 108 h tempe also showed the potency, but at slightly higher IC50 (5.20 ± 1.01 μg/mL). Both acetone and ethanol extracts of 108 and 120 h tempe showed high antioxidant activity expressed as percent inhibition with no significant difference. However, acetone extracts of 120 h tempe (81.31 ± 3.70 %) had better ability to inhibit oxidation reaction than that of ethanol extracts (75.77 ± 6.00 %). It can be concluded that the cytotoxic activity of tempe from 0–156 h of fermentation is positively correlated to their corresponding antioxidant property. Longer fermentation time, up to 108 h, increased the ability of tempe to inhibit the growth of MCF-7 breast cancer cells and oxidative reaction. But extended fermentation time, up to 156 h, tends to decrease its ability. Further studies are encouraged to identify the active components contained in each extract.

Keywords: antioxidant property, cytotoxic activity, extracts, overripe tempeh

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Authors: Ting Wu, Feiting Hu, Xinyue Zhang, Shuxin Tang, Xiaoyun Xu

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As a by-product of yuba, processing wastewater of Yuba (PWY) contains many bioactive components such as soybean isoflavones, soybean polysaccharides and soybean oligosaccharides, which is a good source of prebiotics and has a potential of high value utilization. The use of Lactobacillus plantarum to ferment PWY can be considered as a potential biogenic element, which can regulate the balance of intestinal microbiota. In this study, firstly, Lactobacillus plantarum was used to ferment PWY to improve its content of active components and antioxidant activity. Then, the health effect of fermented processing wastewater of yuba (FPWY) was measured in vitro. Finally, microencapsulation technology was used applied to improve the sustained release of FPWY and reduce the loss of active components in the digestion process, as well as to improving the activity of FPWY. The main results are as follows: (1) FPWY presented a good antioxidant capacity with DPPH free radical scavenging ability (0.83 ± 0.01 mmol Trolox/L), ABTS free radical scavenging ability (7.47 ± 0.35 mmol Trolox/L) and iron ion reducing ability (1.11 ± 0.07 mmol Trolox/L). Compared with non-fermented processing wastewater of yuba (NFPWY), there was no significant difference in the content of total soybean isoflavones, but the content of glucoside soybean isoflavones decreased, and aglyconic soybean isoflavones increased significantly. After fermentation, PWY can effectively reduce the soluble monosaccharides, disaccharides and oligosaccharides, such as glucose, fructose, galactose, trehalose, stachyose, maltose, raffinose and sucrose. (2) FPWY can significantly enhance the growth of beneficial bacteria such as Bifidobacterium, Ruminococcus and Akkermansia, significantly inhibit the growth of harmful bacteria E.coli, regulate the structure of intestinal microbiota, and significantly increase the content of short-chain fatty acids such as acetic acid, propionic acid, butyric acid, isovaleric acid. Higher amount of lactic acid in the gut can be further broken down into short chain fatty acids. (3) In order to improve the stability of soybean isoflavones in FPWY during digestion, sodium alginate and chitosan were used as wall materials for embedding. The FPWY freeze-dried powder was embedded by the method of acute-coagulation bath. The results show that when the core wall ratio is 3:1, the concentration of chitosan is 1.5%, the concentration of sodium alginate is 2.0%, and the concentration of calcium is 3%, the embossing rate is 53.20%. In the simulated in vitro digestion stage, the release rate of microcapsules reached 59.36% at the end of gastric digestion and 82.90% at the end of intestinal digestion. Therefore, the core materials with good sustained-release performance of microcapsules were almost all released. The structural analysis results of FPWY microcapsules show that the microcapsules have good mechanical properties. Its hardness, springness, cohesiveness, gumminess, chewiness and resilience were 117.75± 0.21 g, 0.76±0.02, 0.54±0.01, 63.28±0.71 g·sec, 48.03±1.37 g·sec, 0.31±0.01, respectively. Compared with the unembedded FPWY, the infrared spectrum results showed that the microcapsules had embedded effect on the FPWY freeze-dried powder.

Keywords: processing wastewater of yuba, lactobacillus plantarum, intestinal microbiota, microcapsule

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Authors: Solomon Assefa Huluka

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Wounds account for severe morbidity, socioeconomic distress, and mortality around the globe.For several years, various herbal products are used to expediteand augment the innate wound healing process. In Ethiopian folkloricmedicine, Verbascum sinaiticum L. (V. sinaiticum) is commonlyapplied as a wound-healing agent. The present study investigated the potential wound healing and antioxidant properties of hydroalcoholic leaf extract of V. sinaiticum. The 80% methanol extract, formulated as 5% (w/w) and 10% (w/w) ointments, was evaluated in excision and incision wound models using nitrofurazone and simple ointment as positive and negative controls, respectively. Parameters such as wound contraction, period of epithelialization, and tensile strength were determined. Moreover, its in vitro antioxidant property was evaluated using a DPPH assay. In the excision model, both doses (5% and 10% w/w) of the extract showed a significant (p<0.001) wound healing efficacy compared to the negative control, as evidenced by enhanced wound contraction rate and shorter epithelialization time records. In the incision model, the lower dose (5% w/w) ointment formulation of the extract exhibited the maximum increment in tensile strength (85.6%) that was significant (p<0.001)compared to negative and untreated controls. Animals treated with 5% w/wointment, furthermore, showed a significantly (p < 0.05) higher percentage of tensile strength than nitrofurazone treated ones. Moreover, the hydroalcoholic extract of the plant showed a noticeable free radical scavenging property. The result of the present study upholds the folkloric use of V. sinaiticum in the treatment of wounds.

Keywords: wound healing, antioxidant, excision wound model, incision wound model, verbascum sinaiticum

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Authors: Oumayma Tajouri

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The relationship between total quality management (TQM) practices and innovation is conflictual. Some scholars suggest that TQM has an effect on incremental improvement and would not lead to innovation and creativity. The purpose of this paper is to analyse the association between TQM and different types of innovation. Our goal is to examine to what extent the implementation of TQM practices is indeed supporting innovation in the Tunisian ISO 9001 certified industries. Using a self-administered survey to sample ISO9001 certified industry companies, this study examines five hypotheses and tests the relation between TQM practices and innovation. The principal finding of this study is that TQM has significant and positive effects on innovation in the Tunisian context. The results support that TQM has an influence on incremental, radical, and administrative innovation.

Keywords: total quality management, incremental innovation product and/service, radical innovation product/service, incremental innovation process, radical innovation process, administrative innovation

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Authors: L. Mallesha, C. S. Karthik, P. Mallu

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A series of new [1-(substituted-benzoyl)-piperidin-4-yl]-(2,4-difluoro-phenyl)-methanone oxime derivatives, 3(a-f) were synthesized and characterized by different spectral studies. All compounds were evaluated for their in vitro antibacterial activity against bacterial strains. These compounds were screened for their antioxidant activity by DPPH• and Fe2+ chelating assay. Antiproliferative effects were evaluated using the MTT assay method against two human cancer cell lines and one astrocytoma brain tumor cell line. Compound 3b exhibited moderate antibacterial activity when compared with other compounds. All the compounds showed antioxidant activity, where compound 3f was the best radical scavenger and Fe2+ ion scavenger. Compounds, 3b, and 3d showed good activity on all cell lines, whereas the other compounds in the series exhibited moderate activity.

Keywords: Piperidine, antibacterial, antioxidant, antiproliferative

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Authors: Hafida Merzouk

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Urinary tract infections are among the most serious public health issues in all age groups. Thus, the empirical therapy should based on local levels of resistance, as indicated in several studies from different countries, to effectively avoid the emergence of multidrug-resistant bacterial strains and recurrent infections. Numerous effective antibiotic treatments are available, but wouldbe ineffective for treating recurrent cystitis caused by a urinary tract infection, as well as the emergence of drug resistance. That iswhy the aim of this study was to highlight the antibacterial and the antioxidant activity of 11 medicinal plants used traditionally in Algeria against E. coli, the most responsible urinary tract infections. First, the extraction of total polyphenols with aqueous acetone showed variable yields. The highest yield was obtained by Asplenium trichomanes with 27%, followed by Petroselinum crispum and Ciannamomum cassia with an equal yield of 21%. Artemisia herba-alba gave the lowest yield (9%). The extracts of different plants showed variable contents of phenolic compounds. Reducing power and DPPH (2,2-diphenyl-1-picrylhydrazyl) scavenging activity revealed that most of the extracts studied had significant activity. The anti-free radical activity was very high in the extract of A splenium adiantum-nigrum compared with the other extracts studied, but Petroselinum crispum and Parietaria officinalis had the lowest reducing activity; Antibacterial activity was determined on E. coli strainsusing the diffusion, MICs (Minimum Inhibitory Concentrations) and MBCs (Minimum Bactericidal concentrations) methods. The strains tested were sensitive to most extracts studied, except Asplenium adiantum-nigrum extract, for which both strains showed resistance.

Keywords: E. coli, medicinal plants, phenolic compounds, urinary infections

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Authors: Gulcin Yildiz, Gokcen Izli

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Drying (dehydration) is the process of removing water from food in order to preserve the food. Drying is one of the oldest methods known for the preservation of agricultural products such as fruits and vegetables. Drying of agricultural products enhances their storage life, minimizes losses during storage, and save shipping and transportation costs. Apples are considered excellent candidates for drying. The objective of this research was to investigate the effects of microwave and oven processing on the quality of selected apple products. Red delicious and golden delicious apples were washed, peeled, and sliced. Drying experiments were performed in an oven at 50, 75 and 100 °C and in a microwave at 140 W and 210 W. Quality attributes such as color, total phenolic content and antioxidant capacity of dried samples with different methods were compared with the fresh sample. A Minolta CR-300 Chroma Meter was used to examine color changes in the apples. Total phenolic content was determined using the Folin-Ciocalteu reagent. The free radical scavenging activity of the extract was determined using 1,1-diphenyl-2-picrylhydrazyl (DPPH). It was found that the phenolic contents and antioxidant capacities of dried samples under all drying conditions were decreased compared to the fresh samples. The phenolic contents of microwave dried samples at 140 W and 210 W for both red and golden delicious apples were higher than those of the oven drying at 50, 75 and 100 °C. Similarly, the antioxidant activities of microwave dried samples at 140 W and 210 W were higher than those of the oven drying at 50, 75 and 100 °C for both types of apples. All color parameters (L*, a*, b*) were changed significantly depending on the drying methods and temperatures. The closest color values to the fresh sample were found for the microwave dried samples at 140 W. Microwave drying was proven to be more effective than oven drying.

Keywords: antioxidant capacity, color, golden delicious, microwave, red delicious, total phenolic content

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Authors: Ahmad Shanei, Mohammad Mahdi Shanei

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When a liquid is irradiated with high intensities (> 1 W) and low frequencies (≤ 1 MHz) ultrasound, acoustic cavitation occurs. Acoustic cavitation generates free radicals from the breakdown of water and other molecules. The existence of particles in liquid provide nucleation sites for cavitation bubbles and lead to decrease the ultrasonic intensity threshold needed for cavitation onset. The study was designed to measure hydroxyl radicals in terephthalic acid solutions containing 30 nm gold nanoparticles in a near field of a 1 MHz sonotherapy probe. The effect of ultrasound irradiation parameters containing mode of sonication and ultrasound intensity in hydroxyl radicals production have been investigated by the spectrofluorometry method. Recorded fluorescence signal in terephthalic acid solution containing gold nanoparticles was higher than the terephthalic acid solution without gold nanoparticles. Also, the results showed that any increase in intensity of the sonication would be associated with an increase in the fluorescence intensity. Acoustic cavitation in the presence of gold nanoparticles has been introduced as a way for improving therapeutic effects on the tumors. Also, the terephthalic acid dosimetry is suitable for detecting and quantifying free hydroxyl radicals as a criterion of cavitation production over a range of condition in medical ultrasound fields.

Keywords: acoustic cavitation, gold nanoparticle, chemical dosimetry, terephthalic acid

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Authors: Tahra ElObeid, Omnya Ahmed, Reem Al-Sharshani, Doaa Dalloul, Jannat Alnattei

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Background: Camelus dormedarius camels are also called ‘the Arabian camels’ and are present in the desert area of North Africa and the Middle East. Recently, camel’s milk has a great attention globally because of their proteins and peptides that have been reported to be beneficial for the health and in the management of many diseases. Objectives: This study was designed to investigate the antioxidant, antimicrobial activity and to evaluate the total phenolic content of camel’s milk proteins in Qatar. Methods: Fresh two camel’s milk samples from Omani breed and called Muhajer (camel’s milk A and B) were collected on the 1st of the December. Both samples were from the same location Al- Shahaniyah, Doha, Qatar, but from different local private farms and feeding system. Camel’s milk A and B were defatted by centrifugation and their proteins were extracted by acid and thermal precipitation. The antioxidant activity was determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Total phenolic compound (TPC) was evaluated by Folin-Ciocalteu reagent (FCR). On the other hand, the antimicrobial activity against eight different type of pathogenic bacteria was evaluated by disc diffusion method and the zone of inhibition was measured. Results: The of the total phenolic content of whole milk in both camel’s milk A and B were significantly the highest among the protein extracts. The % of the DPPH radical inhibition of casein protein in both camel’s milk A and B were significantly the highest among the protein extracts. In this study, there were marked changes in the antibacterial activity in the different camel milk protein extracts. All extracts showed bacterial overgrowth. Conclusion: The antioxidant activity of the camel milk protein extracts correlated to their unique phenolic compounds and bioactive protein peptides. The antimicrobial activity was not detected perhaps due to the technique, the quality, or the extraction method. Overall, camel's milk exhibits a high antioxidant activity, which is responsible for many health benefits besides the nutritional values.

Keywords: camels milk, antioxidant content, antimicrobial activity, proteins, Qatar

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Authors: Kanika Kalra, Harmeet Kaur, Dinesh Goyal

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Total phenolics were extracted from waste orange peels by solvent extraction and alkali hydrolysis method. The most efficient solvents for extracting phenolic compounds from waste biomass were methanol (60%) > dimethyl sulfoxide > ethanol (60%) > distilled water. The extraction yields were significantly impacted by solvents (ethanol, methanol, and dimethyl sulfoxide) due to varying polarity and concentrations. Extraction of phenolics using 60% methanol yielded the highest phenolics (in terms of gallic acid equivalent (GAE) per gram of biomass) in orange peels. Alkali hydrolyzed extract from orange peels contained 7.58±0.33 mg GAE g⁻¹. By using the solvent extraction technique, it was observed that 60% methanol is comparatively the best-suited solvent for extracting polyphenolic compounds and gave the maximum yield of 4.68 ± 0.47 mg GAE g⁻¹ in orange peel extracts. DPPH radical scavenging activity and reducing the power of orange peel extract were checked, where 60% methanolic extract showed the highest antioxidant activity, 85.50±0.009% for DPPH, and dimethyl sulfoxide (DMSO) extract gave the highest yield of 1.75±0.01% for reducing power ability of the orange peels extract. Characterization of the polyphenolic compounds was done by using Fourier transformation infrared (FTIR) spectroscopy. Solvent and alkali hydrolysed extracts were evaluated for antibacterial activity using the agar well diffusion method against Gram-positive Bacillus subtilis MTCC441 and Gram-negative Escherichia coli MTCC729. Methanolic extract at 300µl concentration showed an inhibition zone of around 16.33±0.47 mm against Bacillus subtilis, whereas, for Escherichia coli, it was comparatively less. Broth-based turbidimetric assay revealed the antibacterial effect of different volumes of orange peel extracts against both organisms.

Keywords: orange peels, total phenolic content, antioxidant, antibacterial

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Authors: E. Esra Kasapbaşı, Büşra Yıldırım

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Weak oxidizing radicals, such as alkyl peroxyl derivatives, react with carotenoids through hydrogen atom transfer to form neutral carotenoid radicals. Using the DFT method, it has been observed that s-cis-β-carotene is more stable than all-transforms. In the context of this study, an attempt is made to explain the reaction mechanism of the isomers of β-carotene, which exhibits antioxidant properties, with n-pentyl peroxide, one of the alkyl peroxyl molecules, using the Density Functional Theory (DFT) method. The cis and transforms of β-carotene are used in the study to determine which form is more reactive. For this purpose, Natural Bond Orbital (NBO) charges of all optimized structures are calculated, and electron transfer is determined by examining electron transitions between Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO). Additionally, the radical character and reaction mechanism of β-carotene in a radical environment are attempted to be explained based on the calculations. The theoretical inclination of whether β-carotene in cis or transforms is more active in reaction is also discussed. All these calculations are performed in the gas phase using the Integral Equation Formalism Polarizable Continuum Model IEFPCM method with dichloromethane as the solvent.

Keywords: β-carotene, n-pentyl peroxyl radical, DFT, TD-DFT

Procedia PDF Downloads 77