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Bioactive Compounds (bioactive + compound)
Selected AbstractsLoading of Bacterial Cellulose Aerogels with Bioactive Compounds by Antisolvent Precipitation with Supercritical Carbon DioxideMACROMOLECULAR SYMPOSIA, Issue 2 2010Emmerich Haimer Abstract Bacterial cellulose aerogels overcome the drawback of shrinking during preparation by drying with supercritical CO2. Thus, the pore network of these gels is fully accessible. These materials can be fully rewetted to 100% of its initial water content, without collapsing of the structure due to surface tension of the rewetting solvent. This rehydration property and the high pore volume of these material rendered bacterial cellulose aerogels very interesting as controlled release matrices. Supercritical CO2 drying, the method of choice for aerogel preparation, can simultaneously be used to precipitate solutes within the cellulose matrix and thus to load bacterial cellulose aerogels with active substances. This process, frequently termed supercritical antisolvent precipitation, is able to perform production of the actual aerogel and its loading in one single preparation step. In this work, the loading of a bacterial cellulose aerogel matrix with two model substances, namely dexpanthenol and L-ascorbic acid, and the release behavior from the matrix were studied. A mathematical release model was applied to model the interactions between the solutes and the cellulose matrix. The bacterial cellulose aerogels were easily equipped with the reagents by supercritical antisolvent precipitation. Loading isotherms as well as release kinetics indicated no specific interaction between matrix and loaded substances. Hence, loading and release can be controlled and predicted just by varying the thickness of the gel and the solute concentration in the loading bath. [source] Kinetic and Thermodynamic Solubility Values of Some Bioactive CompoundsCHEMISTRY & BIODIVERSITY, Issue 11 2009Elham Shoghi Abstract Thermodynamic solubility is a decisive physicochemical property in drug development. The Chasing Equilibrium method offers an alternative to the classical procedures to measure the solubility of compounds with acid,base properties. The method is fast and yields accurate results. In this work, the solubility of several compounds including acids and bases was determined through the Chasing Equilibrium approach. A study of experimental conditions in terms of sample weight was performed to measure solubilities. The study shows that only a limited range of weights, depending on the nature and solubility of the compounds, is adequate to obtain reliable results. [source] BIOACTIVE POLAR LIPIDS IN OLIVE OIL, POMACE AND WASTE BYPRODUCTSJOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2008HARALABOS C. KARANTONIS ABSTRACT Olive oil protects against atherosclerosis because of biologically active microconstituents. In this study, total polar lipids from olive oil, pomace, pomace oil and waste byproducts were extracted, fractionated by thin layer chromatography and tested for their bioactivity. The most active ones were further purified on high-performance liquid chromatography, and the resulting lipid fractions were tested for their bioactivity. Bioactive compounds were determined in all samples with the exception of olive pomace oil. These lipids inhibited platelet-activating factor (PAF)-induced platelet aggregation and also induced platelet aggregation. The bioactive compound from olive pomace has been chemically characterized as a glycerylether-sn-2-acetyl glycolipid based on mass spectra. Chemical determinations and mass spectrometry data reinforce the assumption that these active microconstituents share both similar bioactivity and common structural features. The existence of PAF antagonists in polar lipid extracts from olive oil waste by-products render them biologically valuable materials for the food industry that could be used for the production of functional foods. PRACTICAL APPLICATIONS Isolated bioactive polar lipids from waste by-products of the olive oil industry that act as inhibitors of platelet-activating factor (PAF) may be used for enrichment and production of foods with higher nutritional value, as PAF plays a major role in inflammatory disorders, including atherosclerosis development. [source] Impact of high-pressure and traditional thermal processing of tomato purée on carotenoids, vitamin C and antioxidant activityJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 2 2006Concepción Sánchez-Moreno Abstract Bioactive compounds (carotenoids and vitamin C) and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH,) scavenging activity [50% depletion of initial DPPH, radical (EC50) and antiradical efficiency (AE)], in aqueous (AQ) and organic (OR) fractions, were measured in tomato purée subjected to high-pressure (HP) (400 MPa/25 °C/15 min), low pasteurisation (LPT) (70 °C/30 s), high pasteurisation (HPT) (90 °C/1 min), freezing (F) (,38 °C/15 min), and HPT plus F (HPT + F). In addition, physical and physicochemical parameters were evaluated. CIELab uniform colour space parameters (lightness, L*; green-red tonality, a*; and blue-yellow tonality, b*) were significantly higher both in the untreated and in the HP tomato purée than in the rest of the samples. Individual and total carotenoids, and provitamin A carotenoids, were significantly higher in HP tomato purée than in the untreated and other treated tomato purées. Ascorbic acid and total vitamin C were significantly lower in HP, LPT, HPT, and HPT + F tomato purées than in the untreated and F purées. In the AQ fractions, we found an inverse significant correlation between both ascorbic acid and total vitamin C and EC50AQ; and a positive significant correlation with AEAQ. In the OR fractions, a significant correlation was found between EC50OR and AEOR parameters and lycopene and total carotenoids. Total scavenging activity (AQ + OR fractions) in HP tomato purée was similar to that in LPT, HPT, and HPT + F purées. Copyright © 2005 Society of Chemical Industry [source] Development of EuroFIR-BASIS , a composition and biological effects database for plant-based bioactive compoundsNUTRITION BULLETIN, Issue 1 2008L. Black Summary Bioactive compounds, such as those derived from plant foods, are of growing interest to the scientific community and food industry because of their putative health-promoting properties. Increasing evidence reports beneficial effects of bioactive compounds, particularly against cancers, cardiovascular diseases and diabetes. EuroFIR-BASIS (BioActive Substances in Food Information System) is a unique online database that collates international research on the composition and biological effects of plant-based bioactive compounds into a single, comprehensive reference resource. EuroFIR-BASIS covers multiple compound classes and 330 major European food plants with data sourced from quality-assessed, peer-reviewed literature. The database is internet-deployed to ensure widespread accessibility and facilitates searches against a number of different variables. EuroFIR-BASIS is intended for use by a wide audience, including scientists, researchers, epidemiologists, food regulatory authorities and product developers in the food industry. The database has been designed to accommodate continual expansion as research develops to ensure that it remains a current and useable resource. [source] Sweet potato leaves: properties and synergistic interactions that promote health and prevent diseaseNUTRITION REVIEWS, Issue 10 2010Melissa Johnson Sweet potato (Ipomoea batatas) leaves provide a dietary source of vitamins, minerals, antioxidants, dietary fiber, and essential fatty acids. Bioactive compounds contained in this vegetable play a role in health promotion by improving immune function, reducing oxidative stress and free radical damage, reducing cardiovascular disease risk, and suppressing cancer cell growth. Currently, sweet potato leaves are consumed primarily in the islands of the Pacific Ocean and in Asian and African countries; limited consumption occurs in the United States. This comprehensive review assesses research examining the nutritional characteristics and bioactive compounds within sweet potato leaves that contribute to health promotion and chronic disease prevention. Research has affirmed the potential cardioprotective and chemopreventive advantages of consuming sweet potato leaves, thus indicating that increased consumption of this vegetable should be advocated. Since reducing the prevalence of chronic diseases is of public health concern, promoting the consumption of sweet potato leaves warrants further and more intensive research investigation. [source] Radical Reduction of Epoxides Using a Titanocene(III)/Water System: Synthesis of ,-Deuterated Alcohols and Their Use as Internal Standards in Food AnalysisEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 22 2010Tania Jiménez Abstract We describe a comprehensive study into the Cp2TiCl-mediated reductive epoxide ring opening using either water as a hydrogen source or deuterium oxide as a deuterium source. The remarkable chemical profile of this reaction allows access to alcohols with anti-Markovnikov regiochemistry from different epoxides. The use of D2O as a deuterium source leads to an efficient synthesis of ,-deuterated alcohols, including a deuterated sample of tyrosol, a bioactive compound contained in the leaves of the olive, which was successfully applied as an internal standard in food analysis. [source] The 4-acetylantroquinonol B isolated from mycelium of Antrodia cinnamomea inhibits proliferation of hepatoma cellsJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2010Yu-Wei Lin Abstract BACKGROUND:Antrodia cinnamomea is known for its antihepatoma activity, yet the identity of its active compound was unclear. In this study, a 5-ton fermenter was used to prepare sufficient mycelium of A. cinnamomea for active compound isolation and identification. RESULTS: Using antiproliferative activity toward HepG2 cells as guidance in the isolation process, 4-acetylantroquinonol B was purified and identified to be the major bioactive compound of A. cinnamomea cultivated by submerged fermentation. The median effective doses (EC50) of 4-acetylantroquinonol B for HepG2 cells were 0.10 ± 0.00 and 0.08 ± 0.00 µg mL,1 for 72 and 96 h treatments, respectively. The selective indices of 4-acetylantroquinonol B were 100 and 125 for 72 and 96 h treatments, respectively, indicating that this compound had high selective activity for hepatoma cells. CONCLUSION: 4-Acetylantroquinonol B is the major antihepatoma constituent of Antrodia cinnamomea mycelium produced by submerged fermentation. Copyright © 2010 Society of Chemical Industry [source] Assessment of a bioactive compound for its potential antiinflammatory property by tight junction permeabilityPHYTOTHERAPY RESEARCH, Issue 12 2005Young Hoon Bai Abstract Lactobacillus probiotic strains are proving to be abundant sources of bioactive components, including antiinflammatory components. Lifree was made of fruits fermented by Lactobacillus paracasei, Lactobacillus reuterrii and Saccharomyces cerevisiae. This study was designed to test these compounds in cell assays measuring epithelial barrier function and proliferation in the first instance. Cell proliferation was measured in mouse fibroblasts cells (3T3NIH) and rat intestinal epithelial cells (IEC-6), and tight junction activity in the kidney epithelial cell line (MDCK). Tight junction permeability was assessed by measuring transepithelial electrical resistance (TER) across confluent monolayers, following the addition of Lifree with or without a challenge with EGTA. Lifree promoted tight junction formation and recovery following loss of TER from challenge with EGTA. On the other hand, Lifree did not stimulate cell growth in either 3T3NIH and IEC-6 cells. Lifree stimulates tight junction maintenance and formation, suggesting it may have potential antiinflammatory properties. Copyright © 2005 John Wiley & Sons, Ltd. [source] Isolation of an antimicrobial compound from Impatiens balsamina L. using bioassay-guided fractionationPHYTOTHERAPY RESEARCH, Issue 8 2001Xiaolong Yang Abstract By using brine shrimp (Artemia salina) lethality test-guided fractionation, a single bioactive compound (LC50=26,ppm) was isolated from the 95% ethanol extract of the dried aerial parts of Impatiens balsamina L. and subsequently identified as 2-methoxy-1,4-naphthoquinone (MNQ). The structure of MNQ was confirmed by UV, FT-IR, MS, and 1-and 2-D NMR spectroscopy. The antimicrobial activity of MNQ was evaluated using 12 bacterial and eight fungal strains. Five gram-positive and two gram-negative bacteria as well as all eight fungi (including multi-drug resistant strains) tested were highly sensitive to MNQ. A tea prepared according to traditional methods was found to contain sufficient MNQ to account for its antimicrobial properties. Copyright © 2001 John Wiley & Sons, Ltd. [source] Synthesis, characterization and application of poly[(1-vinyl-2-pyrrolidone)- co -(2-hydroxyethyl methacrylate)] as controlled-release polymeric system for 2,4-dichlorophenoxyacetic chloride using an ultrafiltration techniquePOLYMER INTERNATIONAL, Issue 7 2008Guadalupe del C Pizarro Abstract BACKGROUND: Polymers supporting chemicals used in agriculture have recently been developed to overcome the serious environmental problems of conventional agrochemicals. The success of these formulations is based on a suitable choice of polymer support. Degradable polymeric hydrogels are of particular interest. The gradual release of the bioactive agent can be achieved by hydrolytic or enzymatic cleavage of the linking bond. RESULTS: In this context, poly[(1-vinyl-2-pyrrolidone)- co -(2-hydroxyethyl methacrylate)] [poly(NVP- co -HEMA)] has been used as a bioactive carrier reagent. Herein, we report a controlled-release system with the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) using an ultrafiltration system. Hydrolysis was studied by testing the release at various pH values. A high release with poly(NVP- co -HEMA),2,4-D was observed at pH = 7 and 10 after two days (Z = 2). The release percentage of copolymer,herbicide increased at pH = 10. It showed release values between 79.0 and 94.5%. Poly(NVP- co -HEMA),herbicide can release a bioactive compound in aqueous solution at pH = 3, 7 and 10. CONCLUSION: Based on the results of homogeneous hydrolysis, it is argued that the herbicide release rate depends on the pH of the reaction environment. This functional polymer could be employed as a biodegradable material for applications in agrichemical release. Copyright © 2008 Society of Chemical Industry [source] Economical Feasibility Evaluation of an Ethanol Injection Liposome Production PlantCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 1 2010O. R. Justo Abstract Over the past few decades liposomes, which are lipid vesicles useful for the controlled release of numerous bioactive compounds, have attracted significant industrial interest. Several techniques have evolved for the manufacture of liposomes on a small scale. However, production on a commercially feasible scale is still somewhat limited. Therefore, this research intends to evaluate the scale-up potential of a liposome production unit using the ethanol injection method, through preliminary economical feasibility estimation, as an addendum to a pre-existing bioactive compound manufacture plant, with the aim of increasing the compound aggregate value. The ethanol injection technique is selected due to its simplicity and low cost, characteristics that make it easily scalable. The preliminary economic evaluation involves the assessment of capital investment, estimation of operating costs, and analysis of profitability. The results of the economic analysis suggest that the process is economically feasible for a plant with a daily production capacity of 288 L of liposomal suspension. [source] Antioxidant capacity of rapeseed meal and rapeseed oils enriched with meal extractEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 7 2010Aleksandra Szyd, owska-Czerniak Abstract Response surface methodology (RSM) was used to evaluate the quantitative effects of two independent variables: solvent polarity and temperature of the extraction process on the antioxidant capacity (AC) and total phenolics content (TPC) in meal rapeseed extracts. The mean AC and TPC results for meal ranged between 1181,9974,µmol TE/100,g and 73.8,814,mg sinapic acid/100,g of meal. The experimental results of AC and TPC were close to the predicted values calculated from the polynomial response surface models equations (R2,=,0.9758 and 0.9603, respectively). The effect of solvent polarity on AC and TPC in the examined extracts was about 3.6 and 2.6 times greater, respectively, than the effect of processing temperature. The predicted optimum solvent polarity of ,,=,78.3 and 63.8, and temperature of 89.4 and 74.2°C resulted in an AC of 10,014,µmol TE/100,g and TPC of 863,mg SAE/100,g meal, respectively. The phenolic profile of rapeseed meal was determined by an HPLC method. The main phenolics in rapeseed meal were sinapine and sinapic acid. Refined rapeseed oils were fortified with an extract , rich in polyphenols , obtained from rapeseed meal. The supplemented rapeseed oil had higher AC and TPC than the refined oil without addition of meal extracts. However, AC and TPC in the enriched oils decreased during storage. The TPC in the studied meal extracts and rapeseed oils correlated significantly (p<0.0000001) positively with their AC (R2,=,0.9387). Practical applications: Many bioactive compounds extracted from rapeseed meal provide health benefits and have antioxidative properties. Therefore, it seems worth to consider the application of antioxidants extracted from the rapeseed meal for the production of rapeseed oils with potent AC. Moreover, antioxidants extracted from the rapeseed meal were added to refined rapeseed oil in order to enhance its AC. AC was then tested by FRAP assay. FRAP method is based on the reduction of the ferric tripyridyltriazine (Fe3+ -TPTZ) complex to the ferrous tripyridyltriazine (Fe2+ -TPTZ), and it is simple, fast, low cost, and robust method. FRAP method does not require specialized equipment and can be performed using automated, semi-automatic, or manual methods. Therefore the proposed FRAP method can be employed by the fat industry laboratories to asses the AC of rapeseed oils and meal. [source] Solid-Phase Reactive Chromatography (SPRC): A New Methodology for Wittig and Horner,Emmons Reactions on a Column under Microwave IrradiationEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 2 2010Saada C. Dakdouki Abstract A new methodology named solid-phase reactive chromatography (SPRC), which combines reaction, separation, and purification into a single unit for the preparation of small samples, is described. This method was illustrated in the synthesis of some natural bioactive compounds, namely, methoxylated analogues of resveratrol, alkylresorcinols, and 5-aryl-2,4-pentadienoates, over a column of alumina-KF under microwave irradiation by using the Wittig and Horner,Emmons reactions. This approach permitted the preparation of the target olefins with high purity and good to excellent yields in short reaction times. [source] Technology options for new nutritional conceptsINTERNATIONAL JOURNAL OF DAIRY TECHNOLOGY, Issue 2 2002Hannu Korhonen Recent advances in the food and nutrition sciences support the concept that the diet has a significant role in the modulation of various functions in the body. The diet and/or its components may contribute to an improved state of well-being, a reduction of risks related to certain diseases and even an improvement in the quality of life. These new concepts have led to the introduction of a new category of health-promoting foodstuffs, i.e. functional foods. The concern about health embraces a number of driving issues, needs and opportunities which may be approached by designing specific diets from various food raw materials. These tailor-made products provide physiological benefits that are targeted at particular consumer groups. The functionality of functional foods is based on bioactive components, which may be contained naturally in the product but usually require formulation by appropriate technologies in order to optimise the desired beneficial properties. To this end, it is often necessary to develop and apply novel technologies, e.g. membrane separation, high hydrostatic pressure and supercritical fluid extraction techniques. Also the minimal processing concept could be employed in this context. This review discusses the current technological options available and the future challenges faced in the area. Particular attention is paid to the exploitation of bovine colostrum and milk-derived bioactive compounds for the development of functional foods. [source] Invited review: Modelling quality changes of fruits and vegetables during drying: a reviewINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 9 2010Sakamon Devahastin Summary Fruits and vegetables have received much attention as these materials have been reported to contain various phytochemicals, which are claimed to exert many health benefits. When extraction of bioactive compounds cannot be performed on fresh fruits and vegetables, drying needs to be conducted to keep the materials for later use. Dried fruits and vegetables have also been regarded as alternative fat-free snacks and received more attention from the food industry during the past decade. This implies that not only nutritional changes, but also other changes including physical and microstructural changes are of importance and need to be optimised, preferably through the use of various modelling approaches. The objective of this article is to provide a brief review of some advances in modelling quality changes of fruits and vegetables during drying. These include modelling of nutritional, colour and selected physical changes. Approaches to monitoring and modelling microstructural changes are also mentioned. [source] Evaluation of the extraction efficiency for polyphenol extracts from by-products of green kiwifruit juicingINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 12 2009Dongxiao Sun-Waterhouse Summary The health benefits of fruits are attributable in part to their bioactive components such as phenolics and pectic polysaccharides. By-products derived from kiwifruit processing can be a good source of such bioactive compounds. Extracts were produced using different concentrations of ethanol in water (0%, 30%, 50%, 74% and 96% v/v) from by-products (skin, residue and pulp) of the green-fleshed kiwifruit (Actinidia deliciosa,Hayward') juicing process. The amounts of phenolic compounds and uronic acid (UA) as well as the phenolic composition in each extract were determined. Results show that different by-products contained different concentrations of phenolics and pectic polysaccharides. Based on total phenolic contents, 96% v/v ethanol appeared to be the best extraction medium. The 30% or 74% ethanolic dilution was the second best medium for phenolic extraction from skin and pulp/residue, respectively. Water was a good medium for extracting satisfactory quantities of phenolics as well as the highest concentration of pectic polysaccharides. Phenolic profiling by high-performance liquid chromatography (HPLC) was used to detect individual phenolic compounds in an extract. Results using HPLC showed that alkali pre-treatment has improved the extraction efficiency of phenolics as a function of alkali concentration, fruit tissue type, extraction media, by-product preparation method, and class of polyphenols. As a result more efficient methods for both extraction and characterisation of polyphenols could be evaluated. [source] Characterization of blond and Star Ruby (red) Jaffa grapefruits using antioxidant and electrophoretic methodsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 3 2006Shela Gorinstein Summary Antioxidant and electrophoretic methods were used to characterize the quality differences between blond and Star Ruby (red) grapefruits. Dietary fibre, minerals and trace elements, total polyphenols, anthocyanins, flavonoids, phenolic and ascorbic acids were also determined. The antioxidant potential of red grapefruit was significantly higher than that of the blond fruit (P < 0.05) and correlated well with the total polyphenols (R2 from 0.8456 to 0.9711). In both the cultivars studied, thirty-two electrophoretic bands were detected [sodium dodecyl-polyacrylamide gel eletrophoresis (SDS-PAGE)]. The main electrophoretic bands occurred between 20 and 43 kDa in both grapefruits with few minor differences between the varieties. Our findings indicate the following (i) red grapefruit is preferable: it has a higher concentration of bioactive compounds and antioxidant potential than the blond; (ii) 1, 1-diphenyl-2-picrylhydrazyl (DPPH) test is a more sensitive method for the determination of antioxidant potential; (iii) there are some minor differences in electrophoretic patterns; (iv) antioxidant and electrophoretic methods are a good combination for characterization of differences of the same citrus fruits. [source] Catalytic Asymmetric Synthesis of Oxindoles Bearing a Tetrasubstituted Stereocenter at the C-3 PositionADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2010Feng Zhou Abstract The 3,3,-disubstituted oxindole structural motif is a prominent feature in many alkaloid natural products, which include all kinds of tetrasubstituted carbon stereocenters, spirocyclic or not, all-carbon or heteroatom-containing. The catalytic asymmetric synthesis of the tetrasubstituted carbon stereocenter at the C-3 position of the oxindole framework integrates new synthetic methods and chiral catalysts, reflects the latest achievements in asymmetric catalysis, and facilitates the synthesis of sufficient quantities of related compounds as potential medicinal agents and biological probes. This review summarizes the recent progress in this area, and applications in the total synthesis of related bioactive compounds. [source] Calcium dynamics of hemocytes of the gastropod Biomphalaria glabrata: effects of digenetic trematodes and selected bioactive compoundsINVERTEBRATE BIOLOGY, Issue 1 2000Lynn A. Hertel Abstract. Two fluorescent calcium indicators, Calcium Green AM (CG) and Fura Red AM (FR), were used in conjunction with confocal microscopy to monitor hemocyte calcium dynamics following exposure to digenetic trematode larvae or relevant bioactive compounds. Changes in intracellular calcium levels, as measured by fluctuations in the CG/FR ratio, were correlated with hemocyte morphological changes. Hemocytes exposed to culture medium remained spread and had few calcium transients. However, following exposure to sporocysts, sporocyst secretory-excretory products, or small rediae of Echinostoma paraensei in culture medium, significantly more hemocytes both rounded up and exhibited calcium transients, though some hemocytes showed one response or the other but not both. Hemocytes did not respond significantly to large rediae, to sporocysts of another digenean (Schistosoma mansoni), or to bacterial lipopolysaccharides. Exposure to either zymosan particles or mannose BSA provoked responses similar to those seen with sporocysts of E. paraensei Caffeine caused rounding but no calcium transients, and phorbol myristate acetate provoked calcium transients but no rounding. The results show that sporocysts and small rediae of E. paraensei have pronounced effects on hemocyte rounding and calcium dynamics, and that these two events can occur independently of one another. This suggests that parasites may influence hemocytes in at least two separate ways. [source] Insecticidal activities of secondary metabolites of endophytic Pencillium sp. in Derris elliptica BenthJOURNAL OF APPLIED ENTOMOLOGY, Issue 8 2005M. Y. Hu Abstract:, A strain of endophytic Pencillium sp., which might produce rotenone or its analogues and showed bioactivity against aphids, was isolated from the fresh roots of Derris elliptica Benth. A total of 12 fractions, isolated from the chloroform extract of endophytic Pencillium sp. mycelia by silica gel column, were tested by bioassay and high-performance liquid chromatography (HPLC), and the more bioactive fractions were found to be D, E and J. Against the adult turnip aphid, Lipaphis erysimi, by dipping at a concentration of 1 mg/ml, the corrected mortalities of fraction D, E and J were 57.68, 63.28 and 69.74% after 48 h of treatment respectively. The three fractions also showed strong antifeeding activity against third instar larvae of Plutella xylostella in a laboratory bioassay. One absorption peak was detected in the HPLC picture of fraction D, it had a similar retention time as that of rotenone, and the chemical constituent, related to the absoption peak, had the same ultraviolet absorption picture as that of rotenone. Then it could be further concluded that the bioactive compounds in the fraction D could be rotenone or its analogous compounds. [source] Mycelium cultivation, chemical composition and antitumour activity of a Tolypocladium sp. fungus isolated from wild Cordyceps sinensisJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2006P.H. Leung Abstract Aims:, To examine and illustrate the morphological characteristics and growth kinetics of Cs-HK1, a Tolypocladium fungus, isolated from wild Cordyceps sinensis in solid and liquid cultures, and the major chemical constituents and antitumour effects of Cs-HK1 mycelium. Methods and Results:, The Cs-HK1 fungus was isolated from the fruiting body of a wild C. sinensis and identified as a Tolypocladium sp. fungus. It grew rapidly at 22,25°C on a liquid medium containing glucose, yeast extract, peptone and major inorganic salts, with a specific growth rate of 1·1 day,1, reaching a cell density of 23·0 g dw l,1 in 7,9 days. Exopolysaccharides accumulated in the liquid culture to about 0·3 g l,1 glucose equivalent. In comparison with natural C. sinensis, the fungal mycelium had similar contents of protein (11·7,,g) and carbohydrate (654·6,,g) but much higher contents of polysaccharide (244·2 mg vs 129·5 mg), adenosine (1116·8,,g vs 264·6 ,g) and cordycepin (65·7 ,g vs 20·8 ,g) (per gram dry weight). Cyclosporin A, an antibiotic commonly produced by Tolypocladium sp., was also detected from the mycelium extract. The hot water extract of mycelium showed low cytotoxic effect on B16 melanoma cells in culture (about 25% inhibition) but significant antitumour effect in animal tests, causing 50% inhibition of B16 cell-induced tumour growth in mice. Conclusions:, The Tolypocladium sp. fungus, Cs-HK1, can be easily cultivated by liquid fermentation. The mycelium biomass contained the major bioactive compounds of C. sinensis, and the mycelium extract had significant antitumour activity. Significance and Impact of the Study:, The Cs-HK1 fungus may be a new and promising medicinal fungus and an effective and economical substitute of the wild C. sinensis for health care. [source] Purification and characterization of a 630 kDa bacterial killing metalloprotease (KilC) isolated from plaice Pleuronectes platessa (L.), epidermal mucusJOURNAL OF FISH DISEASES, Issue 5 2008T Tvete Abstract Antibacterial chemicals in the mucus of fish such as lysozyme, lectins, peptides and proteases provide an efficient first line of defence against pathogens. This study shows that there are at least three antibacterial proteins in plaice skin mucus in addition to lysozyme. One of these proteins is responsible for approximately 74% of the antibacterial activity and is a 630 kDa protease complex designated KilC (bacterial killing metalloprotease C). Purified KilC kills the bacteria Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Pseudomonas aeruginosa efficiently. The protease activity of KilC is dependent upon the divalent cation Mg2+ and shows pH dual optima of 5.0 and 8.0. The enzyme has a temperature optimum of 25 °C and is made up of at least five different sized peptides. Studies with protease inhibitors show that the catalytic site of KilC may be cysteine- or serine protease-like. KilC may kill bacterial cells by acting directly upon the bacteria or by producing low molecular weight bioactive compounds such as peptides. [source] Probiotic Strains as Starter Cultures Improve Angiotensin-converting Enzyme Inhibitory Activity in Soy YogurtJOURNAL OF FOOD SCIENCE, Issue 8 2005O.N. Donkor ABSTRACT Suitability of soy yogurt as a system for delivering probiotics and other bioactive compounds was assessed by fermenting soy milk using starter culture containing Lactobacillus delbrueckii ssp. bulgaricus Lb1466, Streptococcus thermophilus St1342, and probiotic organisms (Lactobacillus acidophilus LAFTI® L10, Bifidobacterium lactis LAFTI® B94, and Lactobacillus paracasei LAFTI® L26). Fermentations were terminated at different pH of 4.50, 4.55, and 4.60 and metabolic patterns of cultures (viability, proteolytic activity, organic acids production, angiotensin-converting enzyme (ACE) inhibitory activity) were investigated during 28 d of storage at 4 °C. The presence of probiotics enhanced the growth of L. delbrueckii ssp. bulgaricus Lb1466 and S. thermophilus St134 in soy yogurt in comparison to the control produced by sole yogurt culture. In general, different termination pH had no effect (P > 0.05) on the viability of probiotic organisms that maintained good viability in soy yogurt during cold storage. Higher levels of essential growth factors in the form of peptides and amino acids in soy yogurts may have promoted the growth of L. acidophilus LAFTI® L10, B. lactis LAFTI® B94, and L. paracasei LAFTI® L26. The use of probiotic strains as a part of starter culture in soy yogurt resulted in a substantial increase in in vitro ACE inhibitory activity compared with the control produced by yogurt culture only. This improvement of ACE inhibition in soy yogurt is partly due to higher proteolytic activity of probiotics. [source] Insect growth-reducing and antifeedant activity in Eastern North America hardwood species and bioassay-guided isolation of active principles from Prunus serotinaAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2000S. Omar Abstract 1 Thirty extracts of wood and bark of hardwood trees from Eastern North America were examined for insect growth-reducing activity in a bioassay with European corn borer, Ostrinia nubilalis, and an antifeedant bioassay with the rice weevil, Sitophilus oryzae. 2 Nine of the bark extracts and four of the wood extracts showed significant growth reducing effects at 0.5% in meridic diets, whereas only two bark extracts and one wood extract showed significant antifeedant effect at the same concentration. 3 Slower growing tree species were more biologically active than fast growing ones. Isolation of the bioactive compounds in one of the active species, Prunus serotina, showed that naringenin, its derivative methoxynaringenin, and eriodictyol were responsible for the antifeedant effects. [source] Preparation, characterization and biological evaluation of 99mTc(CO)3 -labelled cyclic polyaminesJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 14 2005H. P. Vanbilloen Abstract Three cyclic polyamines, namely 1,4,7-triazacyclononane, 1,4,7,10-tetraazacyclo-dodecane (cyclen) and 1,4,8,11-tetraazacyclotetradecane (cyclam), were evaluated as potential ligands for complexation of a technetium(I) tricarbonyl core. They can be used as bifunctional chelating agents for labelling bioactive compounds. Each of the three ligands forms a positively charged technetium tricarbonyl complex in high yield but heating is required to promote complex formation. The charge of the 99mTc(I)tricarbonyl labelled derivatives was confirmed using electrophoresis, and radio-LC,MS supports their proposed chemical identity. After i.v. injection in mice, the compounds were rapidly cleared from the blood by the hepatobiliary or urinary pathway depending on their lipophilicity. Copyright © 2005 John Wiley & Sons, Ltd. [source] The sacred lotus (Nelumbo nucifera), phytochemical and therapeutic profileJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 4 2009Dr Pulok K. Mukherjee Abstract ObjectivesNelumbo nucifera Gaertn. (Nymphaeaceae), also known as sacred lotus, is a well known medicinal plant. This article reviews the traditional uses, phytochemistry and therapeutic reports on different parts of N. nucifera viz. the seeds, rhizomes, leaves and flowers. This review also describes various compounds isolated from different parts of this plant and the therapeutic benefits derived from those phytoconstituents. Key findings There are several therapeutic benefits of this plant for which different parts are used. The extracts of rhizomes, seeds, flowers and leaves have been reported to have varied therapeutic potential. Several bioactive compounds have been derived from these plant parts belonging to different chemical groups, including alkaloids, flavonoids, glycosides, triterpenoid, vitamins etc., which all have their own therapeutic impact. Thus, the pharmacological effects and various active ingredients of different parts of N. nucifera are well understood. Summary In this review we explore the current pharmaceutical, phytochemical and pharmacological knowledge about this well known plant species as well as several emerging aspects for research on N. nucifera. [source] Optimization and validation of a chromatographic method for the simultaneous quantification of six bioactive compounds in Rhizoma et Radix Polygoni CuspidatiJOURNAL OF PHARMACY AND PHARMACOLOGY: AN INTERNATI ONAL JOURNAL OF PHARMACEUTICAL SCIENCE, Issue 1 2008Guangsheng Qian ABSTRACT A reverse-phase HPLC method was developed for simultaneous quantification of six bioactive compounds in Rhizoma et Radix Polygoni Cuspidati. These compounds , polydatin (1), resveratrol (2), rhein (3), emodin (4), chrysophanol (5) and physcion (6) , were analysed from 24 authentic samples of the herb using UV HPLC. Based on the UV absorption characteristics of the six compounds, absorption wavelengths of 306 nm were chosen to quantify compounds 1 and 2, and 290 nm for compounds 3,6. A reliable and reproducible quantitative HPLC method for analysing authentic samples of Rhizoma et Radix Polygoni Cuspidati from different cultivation regions was developed. The results showed that the concentration of compound 1 in samples from Sichuan was almost 2-fold higher than that of samples acquired in Guangxi. Furthermore, compounds 3 and 5 were not found in all the samples tested. Thus, instead of using polydatin (1) and emodin (4) as markers for quality assessment, as in conventional practice, these findings show that compounds 2 and 6 are more suited to act as marker compounds for a more specific assessment of the quality of this herb. [source] MOLECULAR AND PHYLOGENETIC CHARACTERIZATION OF PHORMIDIUM SPECIES (CYANOPROKARYOTA) USING THE CPCB-IGS-CPCA LOCUS,JOURNAL OF PHYCOLOGY, Issue 1 2005Ivanka Teneva The accurate determination of species of Cyanoprokaryota/Cyanophyceae has many important applications. These include the assessment of risk with regard to blooms in water reservoirs as well as the identification of species capable of producing valuable bioactive compounds. Commonly, Cyanoprokaryota are classified based on their morphology. However, morphological criteria are not always reliable because they may change, for example, due to environmental factors. Thus, genetic and molecular analyses are a promising additional approach, but their application has so far been limited to relatively few genera. In light of this, we present here the first characterization of species and strains of the genus Phormidium Kütz. based on the cpcB-IGS-cpcA locus of the phycocyanin operon. In phylogenetic analyses using deduced amino acid sequences of the cpcB-cpcA regions, Phormidium was found to be polyphyletic. This analysis appeared to be dominated by the cpcB region, which is characterized by a relatively high percentage of informative substitutions. The percentage of variable positions within the cpcB-IGS-cpcA locus overall was 16.5%, thereby indicating a level of divergence remarkably higher than that reported for Nodularia and Arthrospira in previous studies relying on cpcB-IGS-cpcA. Further, alignment of informative nucleotide substitutions in the cpcB-IGS-cpcA sequences revealed a mosaic distribution, which may be indicative of genetic recombination events. Finally, the length and sequences of the IGS region alone proved useful as markers to differentiate the cyanobacterial genus Phormidium. However, whether the IGS region per se is sufficiently discriminatory to differentiate between Phormidium species or even strains requires further investigation using newly identified Phormidium sequence data. [source] Strategies of solvent system selection for the isolation of flavonoids by countercurrent chromatographyJOURNAL OF SEPARATION SCIENCE, JSS, Issue 3 2010Fernanda das Neves Costa Abstract Flavonoids form a large class of important naturally occurring bioactive compounds. Their isolation and purification from natural sources can sometimes be very difficult and time-consuming when traditional phytochemical techniques are used. Countercurrent chromatography (CCC), a support-free liquid,liquid partition chromatography technique, is very useful for the isolation of polar compounds and its use is increasing in the natural products field. In this paper, we propose strategies of solvent system selection for the isolation of flavonoids by CCC, based on data from the literature, plus incorporation of own practical experiences. The selected references report the isolation of over 300 different flavonoid compounds from more than 100 plant species, using 40 different solvent systems, showing the versatility of this technique. The solvent system hexane-ethylacetate-methanol-water is proposed as a starting point for the separation of samples containing free flavonoids, as it was cited in more than 60% of the papers. A "fine tuning" step is proposed at each level of this solvent family. Other modifications include exchanging the alcohol in the system as well as introducing a fifth solvent. The solvent system ethyl-acetate-butanol-water is proposed as the starting point for glycosylated flavonoids. Other solvent systems are also discussed. The use of gradients is proposed for samples containing both free and glycosylated flavonoids, as the polarity window is larger in these cases. High-speed countercurrent chromatography was used in 89% of the reviewed data. [source] | ||||||||||||||||||||||||||||||||||||||||