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Search Results: 1 - 10 of 6256 matches for " active compounds "
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Synthesis and antimicrobial activity of Ibuprofen derivatives  [PDF]
Ibtihal Q. Abdulla
Natural Science (NS) , 2014, DOI: 10.4236/ns.2014.62008
Abstract:

In order to reduce the ulcerogenic effect of ibuprofen, its carboxylic group has been converted into 5-membered and 6-membered heterocyclic rings. Various 1,3,4-thiadaizo (y), imidazo [2,1-b] [1,3,4] thiadiazoles (1a-d), 1,3-oxazin-2-yl (2), quinazolin-2-yl (3, 4 and 5), hydrazine, pyrazole (6), pyrazone (7, 8) and oxadiazole (9, 12). Derivatives of ibuprofen were prepared by cyclization under various reaction conditions in a very good yield. The microbial inhibitory effect of the new agents has been assessed in vitro against Gram-positive and Gram-negative bacteria activity. Compounds (4, 5, and 8) showed the highest antibacterial activities compared to other compounds and standard drugs. However, compound (1b) showed the lowest antibacterial activity compared to other compounds. All compounds have been characterized by IR, 1H NMR and C.H.N analysis.

Detection of Some Active Compounds in Aqueous and Ethanolic Extracts of Iraqi Propolis and Examine Their Antibacterial Effects
Tariq N. Musa,Nidhal M. Salih,Wisam S. Ulaiwi
Pakistan Journal of Nutrition , 2012,
Abstract: The crude Iraqi propolis has been collected from an area surrounding by eucalyptus trees at the west of Baghdad city. The aqueous and ethanolic total soluble solids of crude Iraqi propolis were found to be 13.9 and 34.5% respectively. The quantitatively detection of propolis extract refer to the presence of phenolic compounds (such as flavonoids) as the mainly active components. Spectrophotometric analysis was used to determine flavonoids in the local propolis extracts. Flavones and flavonols were determined using aluminum chloride and expressed as quercetin equivalent and were found 2.1 and 6.71% in aqueous and ethanolic extracts respectively. The flavanones were determined using 2, 4-dinitrophenyl hydrazine and expressed as naringenin and found to represent 4.27 and 13.65% of aqueous and ethanolic extracts. Total phenolic, free phenolic and tannin compounds were determined in crude propolis using Lowenthal-Proctor method and were found 9.98, 8.32 and 1.66% by using aqueous extraction and 24.80, 22.72 and 2.08% by ethanol extraction respectively. The inhibitory action of aqueous and ethanolic extract with concentrations 120, 240…to 1200 and 2000, 2500…to 4000 ppm were examined against gram-positive bacteria (Staphylococcus aureus, Bacillus cereus and Bacillus stearothermophilus) and gram-negative bacteria (Escherichia coli, Salmonella enteritidis and Pseudomonas fluorescens). The ethanolic extract of local propolis showed highly inhibitory percentages (up to 83.80% against gram-negative and 87.80% against gram-positive) as compared with aqueous extract (70.58% against gram-negative and 59.59% against gram-positive).
Alumina and Silica Oxides as Catalysts for the Oxidation of Benzoins to Benzils under Solvent-free Conditions
N. Noroozi –Pesyan,A. H. Dabbagh
Molecules , 2005, DOI: 10.3390/10111364
Abstract: Alumina or silica gel are used as catalysts for a solvent-free oxidation of benzoins to the corresponding benzils. These catalysts are easily recovered after completion of the reactions, which are carried out either by heating in a sand bath or using microwave irradiation. Comparison of the results obtained with both catalysts indicates that all the reactants examined were oxidized faster on alumina than on silica under these conditions.
Funkcionalna Hrana - Uloga U Unapre enju Zdravlja
Ivanka Mileti , Sla ana obaji , Bri ita or evi
Journal of Medical Biochemistry , 2008, DOI: 10.2478/v10011-008-0017-0
Abstract: Functional foods are foods that may provide a health benefit beyond basic nutrition. Numerous scientifically proven pieces of evidence in many epidemiological studies indicate that nutrition abundant in certain foods (e.g. fruits and vegetables) is directly correlated with a decreased risk of degenerative diseases. Biologically active compounds in functional foods may impart health benefits or desirable physiological effects. Functional attributes of many traditional foods are being discovered, while new food products are being developed with beneficial components. These results are closely related to nutrition's potentials in preventing chronic diseases. Based on these facts the concept of functional foods has been developed. Rigorous scientific investigation has to confirm the positive physiological effects of these compounds upon health. Labeling claims that are used on functional foods are of two types: (1) structure and function claims, which describe effects on normal functioning of the body, but not claims that the food can treat, diagnose, prevent, or cure a disease (claims such as promotes regularity , helps maintain cardiovascular health , and supports the immune system fit into this category); and (2) disease-risk reduction claims, which imply a relationship between dietary components and a disease or health condition. Structure and function claims do not require preapproval by the FDA, and they require much less stringent scientific consensus than disease-risk reduction claims. Many biologically active compounds are unstable during treatments and storage. They undergo many common chemical reactions such as oxidation, hydrolysis, thermal degradation and Maillard reaction, contributing to the lowering of bioavailability. Anyhow, beneficial effect of bioactive compounds depends directly on the applied treatment in the production of foods.
Use of Essential Oils to Inhibit Alicyclobacillus Acidoterrestris: A Short Overview of the Literature
Antonio Bevilacqua
Frontiers in Microbiology , 2011, DOI: 10.3389/fmicb.2011.00195
Abstract: Essential oils (EOs) are promising and friendly antimicrobials for the prolongation of the shelf life of many foods. They have been extensively used to inhibit spoiling and pathogenic microorganisms of many kinds of products like fruit juices and acidic drinks. Therefore, they could be used successfully to control the germination of spores of Alicyclobacillus acidoterrestris, that finds in these products an optimal environment for growth. This paper reports a brief overview of the literature available, focusing on the effects of EOs toward alicyclobacilli.
Recent Advance in Heterocyclic Organozinc and Organomanganese Compounds; Direct Synthetic Routes and Application in Organic Synthesis
Seung-Hoi Kim,Reuben D. Rieke
Molecules , 2010, DOI: 10.3390/molecules15118006
Abstract: A practical synthetic route for the preparation of 2-pyridyl and 3-pyridyl derivatives has been accomplished by utilizing a simple coupling reaction of stable 2-pyridylzinc bromides and 3-pyridylzinc bromides. The organozincs used in this study were easily prepared via the direct insertion of active zinc into the corresponding bromopyridines. The subsequent coupling reactions with a variety of different electrophiles have afforded the corresponding coupling products. Using highly active manganese, a variety of Grignard-type organomanganese reagents have been obtained. The subsequent coupling reactions of the resulting organomanganese reagents with several electrophiles have also been accomplished under mild conditions.
Biossurfactantes: propriedades e aplica??es
Nitschke, Marcia;Pastore, Gláucia Maria;
Química Nova , 2002, DOI: 10.1590/S0100-40422002000500013
Abstract: chemically synthesized surfactants are widely used for many purposes in almost every sector of modern industry. surface-active compounds of biological origin (biosurfactants) have been gaining attention in recent years because of some advantages such as biodegradability, low toxicity, diversity of applications and functionality under extreme conditions. microbial biosurfactants are useful in bioremediation of water and soil, enhanced oil recovery, and in many formulations of petrochemical, chemical, pharmaceutical, food, cosmetic and textile industries. the importance of biosurfactants, their characteristics and industrial applications are discussed.
Produ??o de biossurfactante por levedura
Fontes, Gizele Cardoso;Amaral, Priscilla Filomena Fonseca;Coelho, Maria Alice Zarur;
Química Nova , 2008, DOI: 10.1590/S0100-40422008000800033
Abstract: biosurfactants are molecules extracellularly produced by bacteria, yeast and fungi that have significant interfacial activity properties. this review focuses on relevant parameters that influence biosurfactant production by yeasts. many works have investigated the optimization of yeast biosurfactant production, mainly within the last decade, revealing that the potential of such microorganisms is not well explored in the industrial field. the main points to increase the process viability lays on the reduction of the production costs and enhancement of biosynthesis efficiency through optimization the culture conditions (carbon and nitrogen source, ph, aeration, speed agitation) and the selection of inexpensive medium components.
Biologically active components of soybeans and soy protein products: A review
Bara? Miroljub B.,Stanojevi? Sla?ana P.,Pe?i? Mirjana B.
Acta Periodica Technologica , 2005, DOI: 10.2298/apt0536155b
Abstract: Soybeans provide a source of low-cost protein with good nutritional and physico-chemical properties. Recently, soybean has received much attention because of its potential role in preventing and treating several diseases including cancer and other human chronic diseases. Health benefits of soy diet are attributed to the minor soybean constituents (calledphytochemicals). Soybean contains a variety of phytochemicals with demonstrated anticancer activity, including bioactive proteins andpolypeptides (trypsin inhibitors and the most recently discoveredpeptide lunasin), isofl avones, phytic acid, phytosterols and saponins. The present review provides an overview of recent knowledge about biologically active components of soybean.
Biossurfactantes: propriedades e aplica es
Nitschke Marcia,Pastore Gláucia Maria
Química Nova , 2002,
Abstract: Chemically synthesized surfactants are widely used for many purposes in almost every sector of modern industry. Surface-active compounds of biological origin (biosurfactants) have been gaining attention in recent years because of some advantages such as biodegradability, low toxicity, diversity of applications and functionality under extreme conditions. Microbial biosurfactants are useful in bioremediation of water and soil, enhanced oil recovery, and in many formulations of petrochemical, chemical, pharmaceutical, food, cosmetic and textile industries. The importance of biosurfactants, their characteristics and industrial applications are discussed.
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