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Simultaneous determination of compounds in Septalen pellets by derivative spectrophotometry
MIRJANA MEDENICA,DARKO IVANOVIC,ANDJELIJA MALENOVIC
Journal of the Serbian Chemical Society , 2000,
Abstract: In this paper, a second-derivative spectrophotometric method of assaying Septalen pellets (Krka, Novo Mesto, Slovenia), which contain lidocaine 1 mg, and cetrimonium bromide 2 mg, is described. Lidocaine, 2-(diethylamino)-N-(2,6-dimethyl-phenyl)-acetamide, is a local anesthetic with pronounced antiarhythmic and anticonvulsant properties. Cetrimonium bromide, N,N,N-trimethyl-l-hexadecanaminium bromide, is a topical antiseptic and cleansing agent. Lidocaine was determined at 250 nm using the "zero crossing" technique because the signals of centrimonium bromide and the colour ingredient are zero at this wavelength. Cetrimonium bromide was determined by correction of the peak amplitude at 215 nm according to lidocaine. In choosing the optimal magnitudes for the simultaneous determination of both drugs, the following criteria were considered: (1) the linearity of the calibration graphs as given by the correlation coefficients, (2) the intercept, (3) the sensitivity as given by the regression coefficient, (4) the degree of interference in the derivative measurement by the presence of the other compound, as given by the relative percent error and by the relative recovery, and (5) the reproducibility, as given by the coefficient of variation, calculated by recording the second-derivative spectra.
Antioxidant Phenolic Compounds of Dracaena Cambodiana  [PDF]
Ying Luo,Hui Wang,Xuerong Xu,Wenli Mei,Haofu Dai
Molecules , 2010, DOI: 10.3390/molecules15128904
Abstract: The antioxidant activities of the petroleum ether, ethyl acetate, n-BuOH and water extract fractions from Dracaena cambodiana Pierre ex Gagnep were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest DPPH˙, ABTS+ and Superoxide anion radical-scavenging capacities. The DPPH˙, ABTS+ and Superoxide anion radical-scavenging capacities of nine compounds isolated from the ethyl acetate fraction were also evaluated. The results indicated that these compounds contributed to the antioxidant activity of D. cambodiana. Therefore, D. cambodiana and these compounds might be used as natural antioxidants.
Phenolic compounds and antioxidant activity of rice
Walter, Melissa;Marchesan, Enio;
Brazilian Archives of Biology and Technology , 2011, DOI: 10.1590/S1516-89132011000200020
Abstract: the aim of this work was to study the phenolic compounds identified in rice, their antioxidant activity and their potential beneficial effects on health. in vitro and in vivo studies evaluating the rice grains with different pericarp colour (light brown, red and black) showed potential beneficial effects on health related to the polyphenol content of the grain, such as reduction of oxidative stress, aid in the prevention of cancer, cardiovascular diseases and complications of diabetes, among others.
Antioxidant Compounds from Propolis Collected in Anhui, China  [PDF]
Haisha Yang,Yuqiong Dong,Huijing Du,Haiming Shi,Yunhua Peng,Xiaobo Li
Molecules , 2011, DOI: 10.3390/molecules16043444
Abstract: The antioxidant activities of the chloroform, ethyl acetate and n-butanol extract fractions from propolis collected in Anhui, China were evaluated in this study. The ethyl acetate fraction contained the highest amount of total phenolics and total flavonoids, and showed the greatest 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging capacities and Ferric Reducing/Antioxidant Power (FRAP). The antioxidant activity of twenty-two compounds isolated from the ethyl acetate fraction was also evaluated using the above-mentioned three assays. The results indicated that phenolics contributed to the antioxidant activity of propolis collected in Anhui, China. Therefore, propolis collected in Anhui, China and its phenolics might be used as a natural antioxidant.
EFFECTIVE ANTIOXIDANT PHENOLIC COMPOUNDS IN SELECTED VARIETIES OF APPLES
Dominika Bon?íková,Tomá? Tóth,Ján Tomá?,Dalaram Suleiman
Potravinarstvo : Scientific Journal for Food Industry , 2012, DOI: 10.5219/222
Abstract: Polyphenolic compounds are effective antioxidant regarding their ability to reat with free radicals of fatty acid and oxygen(free radical scavening effect). One of the richest source of polyphenolic compounds in human nutrition are apples (Malus Mill.). Our work was focused on determinaton of total polyphenols contents and antioxidant activity and evaluate the presence of dislocation active antioxidant components in four of selected varieties of apples Idared, Jonagold, Pinova, Topaz (peel extract and pulp extract).The total contents of phenolic compounds,determined according to the Folin-Ciocalteu reagent spectrofotometric by Lachman and antioxidant activity was measured using a free radical used in this study was 2,2-diphenyl-1-picrylhydrazyl (DPPH). Average content of total polyphenols in selected varieties of apples was 622,67 mg.kg-1 (peel extract) and 568,7mg.kg-1 (pulp etract) after harvesting. Relationships between content of total polyphenols and antioxidant activity is affected by varietal difrences. doi:10.5219/222
Bioactive Compounds and Antioxidant Capacity of Camarosa and Selva Strawberries (Fragaria x ananassa Duch.)  [PDF]
Franco Van De Velde,Anna M. Tarola,Daniel Güemes,María E. Pirovani
Foods , 2013, DOI: 10.3390/foods2020120
Abstract: Strawberries represent an important source of bioactive compounds due to their vitamin C and phenolic compound levels, which present high antioxidant effects, beneficial for the maintenance of consumer’s health. Argentina is the second largest strawberry producer in The Common Market of the Southern Cone (MERCOSUR), covering the main export destinations of Argentinian strawberries, i.e., Canada, United States, and European Union. Information about the bioactive compound occurrence and antioxidant capacity of these fruits is scarce or not available. Health related compounds of strawberry cultivars ( Camarosa and Selva) from different zones of Argentina were investigated. Vitamin C content was in the same range for both studied cultivars. However, Camarosa strawberries, which are the most cultivated, consumed, and exported berries in Argentina, presented higher total phenolic and anthocyanins content, and consequently better in vitro antioxidant capacity. Moreover, there were differences in the occurrence and concentration in the phenolic compound profiles for both cultivars. Camarosa cultivar presented higher content of anthocyanidins, and Selva showed higher total ellagic acid content. The research shows that Argentina’s strawberries are an interesting source of bioactive compounds comparable to those in other parts of the world.
Phenolic Compounds and Antioxidant Activities of Liriope muscari  [PDF]
Wen Jie Li,Xian Long Cheng,Jing Liu,Rui Chao Lin,Gang Li Wang,Shu Shan Du,Zhi Long Liu
Molecules , 2012, DOI: 10.3390/molecules17021797
Abstract: Five phenolic compounds, namely N-trans-coumaroyltyramine (1), N-trans-feruloyltyramine (2), N-trans-feruloyloctopamine (3), 5,7-dihydroxy-8-methoxyflavone (4) and (3S)3,5,4′-trihydroxy-7-methoxy-6-methylhomoisoflavanone (5), were isolated from the fibrous roots of Liriope muscari (Liliaceae). Compounds 2–5 were isolated for the first time from the Liriope genus. Their in vitro antioxidant activities were assessed by the DPPH and ABTS scavenging methods with microplate assays. The structure-activity relationships of compounds 1–3 are discussed.
Antioxidant Activity of Polyphenolic Compounds from Dalbergia odorifera T. Chen  [PDF]
Jian-Ping Hou,Hou Wu,Chi-Tang Ho,Xin-Chu Weng
Pakistan Journal of Nutrition , 2011,
Abstract: Seven compounds were isolated from Dalbergia odorifera T. Chen and their antioxidant activities were studied with Oil Stability Index (OSI) method, reducing power and radical scavenging methods. The compounds were identified by spectroscopic methods as (1) pinocembrin (2) biochanin A (3) sativanone (4) biochanin B (5) naringenin (6) 3'-hydroxymelanettin and (7) eriodictoyl. Results showed that compounds 6 and 7 exhibited stronger antioxidant activity than commonly used synthetic antioxidant BHT in the presented study.
Susceptibility of Pediococcus isolates to antimicrobial compounds in relation to hop-resistance and beer-spoilage
Monique Haakensen, David M Vickers, Barry Ziola
BMC Microbiology , 2009, DOI: 10.1186/1471-2180-9-190
Abstract: Lactic acid bacteria susceptibility test broth medium (LSM) used in combination with commercially available GPN3F antimicrobial susceptibility plates was an effective method for assessing antimicrobial susceptibility of Pediococcus isolates. We report the finding of Vancomycin-susceptible Pediococcus isolates from four species. Interestingly, we found that hop-resistant, beer-spoilage, and beer-spoilage gene-harbouring isolates had a tendency to be more susceptible, rather than more resistant, to antimicrobial compounds.Our findings indicate that the mechanisms involved in conferring hop-resistance or ability to spoil beer by Pediococcus isolates are not associated with resistance to antibiotics commonly used for treatment of human infections. Also, Vancomycin-resistance was found to be isolate-specific and not intrinsic to the genus as previously believed.Isolates from the genus Pediococcus are particularly problematic for the brewing industry where hop-compounds are used to provide flavour to beer. Hop-compounds are antimicrobial in that they dissipate the trans-membrane pH gradient of microbes, thereby inhibiting growth and potential spoilage of product [1]. As pediococci are also used as beneficial microbes in the context of food microbiology and animal husbandry (e.g., wine, cheese, and yogurt industries as well as for the production of silage), the emergence of hop-resistant Pediococcus isolates in the brewing industry is of broader interest. These isolates frequently harbour one or more ATP-binding cassette type multidrug resistance (ABC MDR) genes, suggesting that resistance to hop-compounds may also confer resistance to other antimicrobial compounds [2]. We have previously shown that several genes can be correlated with ability of Pediococcus isolates to grow in beer and to resist the antimicrobial activity of hop-compounds [3-5]. These are the ABC MDR genes ABC2, bsrA, bsrB, [6] and horA [2], a putative divalent cation transporter known as hitA [7], and ho
Extraction of interesting organic compounds from olive oil waste
Fernández-Bola?os, Juan,Rodríguez, Guillermo,Rodríguez, Rocío,Guillén, Rafael
Grasas y Aceites , 2006,
Abstract: In the olive fruits there is a large amount of bioactive compounds and substances of high interest. Many of them are known by owing health beneficial properties that contribute to protective effect of the virgin olive oil. During olive oil processing, most of them remain in the olive oil wastes. Although, olive-mill wastewater (OMWW) or “alpechin”, olive oil cake (OOC), and the new by-product, known as “alperujo” in Spain and generated by the two-phase extraction process, represent a major disposal and potentially severe pollution problem for the industry, they are also promising source of substances of high value. This review summarises the last knowledge on the utilisation of residual products, with more than 90 references including articles and patents, which are promising with regard to future application. All these investigations have been classified into two options, the recovery of valuable natural constituents and the bioconversion into useful products. Existe una gran cantidad de compuestos bioactivos y de alto interés presentes en la aceituna. Muchos de ellos se conocen por las cualidades beneficiosas que aportan al aceite de oliva virgen. La mayoría permanecen en mayor cantidad en el subproducto de la extracción del aceite. Aunque, el alpechín, el orujo y el nuevo subproducto de extracción del aceite en dos fases, alperujo, representan un problema potencial de vertido y contaminación, también son una prometedora fuente de compuestos de alto valor. Esta revisión resume lo último que se conoce sobre la utilización de estos residuos en el campo anteriormente mencionado, con más de 90 referencias que incluyen artículos y patentes. Todas estas investigaciones han sido clasificadas en cuanto a la recuperación de constituyentes naturalmente presentes o en cuanto a la bioconversión de los residuos en sustancias de interés.
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