Extracts

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Extracts

  • acetate extract
  • acetone extract
  • acid extract
  • active extract
  • alcohol extract
  • alcoholic extract
  • alkaloid extract
  • allergen extract
  • anthocyanin extract
  • areca nut extract
  • bacterial extract
  • bark extract
  • bean extract
  • biloba extract
  • bone extract
  • brain extract
  • cell extract
  • cell wall extract
  • cell-free extract
  • cellular extract
  • chloroform extract
  • cigarette smoke extract
  • crude cell extract
  • crude extract
  • cytoplasmic extract
  • cytosolic extract
  • dichloromethane extract
  • different extract
  • dna extract
  • dry extract
  • egg extract
  • enzyme extract
  • ethanol extract
  • ethanolic extract
  • ether extract
  • ethyl acetate extract
  • etoh extract
  • faecal extract
  • flour extract
  • flower extract
  • fluid extract
  • food extract
  • fruit extract
  • g extract
  • garlic extract
  • ginkgo biloba extract
  • ginseng extract
  • gland extract
  • grape extract
  • grape seed extract
  • grapefruit seed extract
  • green tea extract
  • herb extract
  • herbal extract
  • hexane extract
  • hot water extract
  • hot-water extract
  • juice extract
  • l. extract
  • leaf extract
  • lipid extract
  • lipophilic extract
  • liquid extract
  • liver extract
  • lyophilized extract
  • malt extract
  • meal extract
  • meoh extract
  • methanol extract
  • methanolic extract
  • mite extract
  • muscle extract
  • natural extract
  • needle extract
  • non-polar extract
  • nuclear extract
  • nut extract
  • officinali extract
  • oil extract
  • olive leaf extract
  • organic extract
  • other extract
  • paste extract
  • peel extract
  • perchloric acid extract
  • petroleum ether extract
  • phenolic extract
  • pine bark extract
  • pituitary extract
  • plant extract
  • polar extract
  • pollen extract
  • polyphenolic extract
  • protein extract
  • red ginseng extract
  • root extract
  • rosemary extract
  • sample extract
  • seed extract
  • skin extract
  • smoke extract
  • soil extract
  • soluble extract
  • solvent extract
  • soy extract
  • soybean extract
  • sperm extract
  • tea extract
  • tissue extract
  • total extract
  • total protein extract
  • urine extract
  • wall extract
  • water extract
  • water-soluble extract
  • whole cell extract
  • willow bark extract
  • wood extract
  • xenopus egg extract
  • yeast extract

  • Terms modified by Extracts

  • extract agar
  • extract alone
  • extract component
  • extract concentration
  • extract decreased
  • extract dilution analysis
  • extract preparation
  • extract rich
  • extract supplementation
  • extract treatment
  • extract used

  • Selected Abstracts


    BIOLOGICAL ACTIVITY OF EXTRACT OF STELLERA CHAMAEJASME AGAINST FIVE PEST INSECTS

    INSECT SCIENCE, Issue 3 2002
    WANG Ya-wei
    Abstract Biological activity of an extract of the root of Stellera chameajasme with ethanol by dip (SCEE) against 5 insect pests, Pieris rapae, Plutella xylostella, Spodoptera litura, Myzus persicae, and Ostrina fumalis as tested. The LD, of stomach poison of SCEE against the fifth instar larvae of P. rapae was 12. 32 ,arvae day 2 after treatment. With SCEE at concentration of 5, 2. 5 and 50 mg/mL, the fifth instar larvae of P. rapae, the third instar larvae of P. xylostella, and the third instar larvae of S. litura by disc leaf dipped method, had corrected mortalities of 100%, 31. 03 % and 16. 67 % 7 days after treatment respectively. The LC50 of SCEE against M. persicae was 0. 599 2 mg/mL after day 2 treatment by leaf dipped method. With SCEE at 10 mg/mL for the third instar larvae of O. furnucalis by mixture pesticide method, the corrected mortalities of 65. 52% and 85. 72% days 7 and day 14 after treatments respectively. The results showed that SCEE possessed strong biological activity to P. rapae, O. furnacalis, and M. persicae, while possessed weak biological activity to S. litura and P. xylostella. [source]


    ANTIOXIDANT ACTIVITIES AND HYPOLIPIDEMIC EFFECTS OF AN AQUEOUS EXTRACT FROM FLOWER BUDS OF CLEISTOCALYX OPERCULATUS (ROXB.) MERR.

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2009
    AND PERRY
    ABSTRACT The antioxidant activities and hypolipidemic effects of aqueous extract from Cleistocalyx operculatus flower buds (COB) (Roxb.) Merr. and Perry, a commonly used material for drink preparation in Vietnam, were investigated in vitro and in diabetic rats. In vitro, the aqueous extract of COB which has highest phenolic and flavonoid contents showed a strong antioxidant effect and highest pancreatic lipase inhibitory activity when compared with green tea and guava leaf extracts. Oral administration of aqueous extract from COB (500 mg/kg body weight/day) on streptozotocin-induced diabetic rats for 8 weeks resulted in significant reduction in the levels of glucose, total cholesterol and triglyceride in plasma as well as the concentration of glucose and sorbitol in the lens. In addition, COB showed significant recovery in the activities of antioxidant enzymes (superoxide dismutase, glutathione S-transferase) and glutathione level in liver with markedly decrease in the lipid peroxide level in liver and lens of the COB-treated diabetic rats. These results indicated that COB showed antioxidant activities, prevention of sorbitol accumulation in lens and hypolipidemic effects in addition to its antidiabetic effects and may be considered as a promising material for the prevention of diabetic complications and metabolic syndrome. PRACTICAL APPLICATIONS In recent years, research on traditional medicinal plants for the management of diabetes has attracted the interest of medical scientists. A suitable plant material for antidiabetes and prevention of diabetic complications should possess various biological components, such as antihyperglycemia, antioxidant activities and antihyperlipidemia, without side effects. In this study, the aqueous extract from Cleistocalyx operculatus flower buds (COB) with high polyphenolic and flavonoid content has shown beneficial biological functions in vitro and in diabetic rats, including antioxidant activity, hypolipidemic and hypoglycemic effects. The results of our study suggest that COB might have a potential role in the management of the prediabetic state and the prevention of diabetic complications. Therefore, there is the possibility for the development of C. operculatus as a beverage for the prevention of diabetes, as well as the prevention of the metabolic syndrome. [source]


    COMPARATIVE STUDIES ON PROTEOLYTIC ACTIVITY OF SPLENIC EXTRACT FROM THREE TUNA SPECIES COMMONLY USED IN THAILAND

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2004
    SUPPASITH KLOMKLAO
    ABSTRACT Proteolytic activities of splenic extract from three tuna species including skipjack tuna (Katsuwonus pelamis), yellowfin tuna (Thunnus albacores) and tongol tuna (Thunnus tonggol) were studied. Optimal activity of splenic extract from all tuna species was at pH 9.0 and 55C when casein was used as a substrate. Among all species tested, yellowfin tuna showed the highest activity, followed by skipjack tuna and tongol tuna. The proteolytic activity was strongly inhibited by soybean trypsin inhibitor, TLCK and partially inhibited by ethylenediaminetetraacetic acid. E-64, N-ethylmaleimide, iodoacetic acid, TPCK and pepstatin A showed no inhibition. The effect of NaCl and CaCl2 on proteolytic activity was also investigated. Activities continuously decreased as NaCl concentration increased, and no activity remained in the presence of 30% NaCl. On the other hand, activities increased as CaCl2 concentration increased. The highest activity was obtained in the presence of 1 mM CaCl2. SDS-substrate gel electrophoresis revealed that major proteinases in splenic extract from different tuna species were different in apparent molecular weights and sensitivity to TLCK. Although the major activity bands of all species were strongly inhibited by soybean trypsin inhibitor, varying sensitivity to TLCK probably implied the differences in binding characteristic of enzyme to substrate and/or inhibitors. The results suggest that major proteinases in spleen of all tuna species were trypsin-like serine proteinases. [source]


    SUPERCRITICAL CARBON DIOXIDE SELECTIVITY TO FRACTIONATE PHENOLIC COMPOUNDS FROM THE DRY ETHANOLIC EXTRACT OF PROPOLIS

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2010
    LOSIANE C. PAVIANI
    ABSTRACT The global yield and composition of extracts obtained by supercritical carbon dioxide (SC-CO2) extraction from a dry ethanolic extract of propolis were measured in order to determine the possibility of using SC-CO2 to fractionate components of interest present in these extracts. The global yield extraction was measured, and also the concentrations of the following phenolic compounds in the resulting supercritical fluid extracts (SFEs): 3,5-diprenyl-4-hydroxycinnamic acid (known as artepillin C), 3-prenyl-4-hydroxycinnamic acid, 4-hydroxycinnamic acid (p- coumaric acid) and 4-methoxy-3,5,7-trihydroxyflavone (kaempferide), of which artepillin C was the target component of greatest interest. The results showed extraction yields between 3.82 (at 150 bar) and 13.07% (at 350 bar), which could be highly correlated with the density of the SC-CO2 at a constant temperature of 60C. The resulting concentrations in the SFE indicated that the selectivity of the carbon dioxide could be manipulated, and it was more selective at lower pressures, although with lower extraction yields. PRACTICAL APPLICATIONS Supercritical fluid extraction is an interesting process for the production of natural extracts because it is a clean process, and extractions using carbon dioxide (CO2) as the solvent have been gaining attention in recent years. This study presented important aspects with respect to the fractionation of a dry ethanolic extract of propolis using supercritical carbon dioxide, and it is important to explore the potential applications of propolis extracts and the biological properties of its fractions in the food, pharmaceutical and cosmetic industries, such as in dental hygiene products, wound healing creams and antibacterial soaps. [source]


    CLARIFICATION AND PURIFICATION OF AQUEOUS STEVIA EXTRACT USING MEMBRANE SEPARATION PROCESS

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 3 2009
    M.H.M. REIS
    ABSTRACT Stevia rebaudiana Bertoni is a native plant from South America and its active constituents have been considered the "sweeteners of the future."Stevia is a natural diet-sweetening source, safe to health and without calories. However, the obtained raw extract is foul smelling, bitter tasting, dark brown colored, and presents suspension matter due to organic and inorganic compounds. Therefore, further purification/clarification is essential in order to get a product of commercial quality. In this work ceramic membranes were applied in the stevia extract clarification process. The process was carried out under different membrane pore sizes and at different pressure values. The best clarification result was obtained with the membrane of 0.1 m at 4 bar. On the other hand, the best condition for the flux was obtained with the membrane of 0.2 m at 6 bar. The process with all the tested membranes and conditions achieved recovery of sweeteners higher than 90%. Finally, a filtration mathematical model was applied to describe the flux behavior, showing that the main fouling phenomenon during the process occurred because of the complete blocking of pores. PRACTICAL APPLICATION Stevia is the world's only all-natural sweetener with zero calories, zero carbohydrates and a zero glycemic index. However, the obtained stevia extract has a dark brown appearance, mainly because of the presence of impurities. In this work the membrane separation process was studied for stevia extract clarification and purification in order to get a product with higher commercial acceptability. The obtained results showed that total clarification and recuperation of sweeteners was almost achieved. Nonetheless, membrane fouling is an inevitable problem during membrane filtration. The mathematical analysis of the fouling occurrences showed that the complete blocking of pores is the main cause for the membrane permeability decrease. [source]


    ADSORPTION CHARACTERISTICS OF CROCIN IN THE EXTRACT OF GARDENIA FRUITS (GARDENIA JASMINOIDES ELLIS) ON MACROPOROUS RESINS

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2009
    BIN YANG
    ABSTRACT To study resin adsorptions and investigate the differences between processes in crude extracts and microfiltrates, the adsorption characteristics of crocin in the extract of Gardenia jasminoides Ellis on 10 macroporous styrene-divinylbenzene (SDVB) resins were investigated. Ground gardenia fruit was extracted with water and the crude extract was partially purified by microfiltration. The crude extract and microfiltrate were mixed with the 10 resins until the adsorption of crocin reached equilibrium on resins. The adsorption followed the pseudo-second-order kinetics closely, but the data also fitted the first-order and intraparticle diffusion models. Furthermore, the Freundlich isotherm was found suitable for describing the equilibrate adsorption data. XAD-1180, HP20, HPD-100A and AB-8 stood out as the best performing resins in terms of their adsorptive capacities and selectivities for crocin. The thermodynamics of the adsorption process was shown to be spontaneous and exothermal in nature, and controlled by physical rather than chemical mechanisms. Adsorption with SDVB resins in conjunction with microfiltration was found to be an efficient process for the purification of crocin in gardenia extract. PRACTICAL APPLICATIONS Macroporous resins have been industrially applied in the recovery and purification of some products from plant extracts. However, there is a lack of understanding of the adsorption process and many of the applications are based on empirical data rather than on predicable models. Therefore, the development of reliable mathematical models that can accurately describe and predicate experimental data of adsorption would be extremely helpful in understanding the adsorption process as well as optimizing the design of adsorption systems. [source]


    AQUEOUS GARLIC EXTRACT AND MICROBIOLOGICAL QUALITY OF REFRIGERATED POULTRY MEAT

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 2 2005
    KEILY ALVES DE MOURA OLIVEIRA
    ABSTRACT The antibacterial effect of garlic extract (5, 10 and 15%) was investigated on poultry carcasses obtained from a slaughterhouse, stored under refrigeration, and evaluated at selected time intervals. The effect of the garlic extract on the microbial contaminants of the poultry carcass surface , Salmonella, strict and facultative aerobic, mesophilic, and total and fecal coliforms , was evaluated. The garlic extract exhibited a concentration-dependent reduction of microbial contamination. Garlic extract concentrations of 10 and 15% were the most effective. The bacteriostatic action of garlic extract against mesophilic microbiota can be observed until the third storage day. The count of total and fecal coliforms remained low during the storage period. Chicken feed was the apparent source of Salmonella contamination, and the aqueous garlic extract was not effective against Salmonella. [source]


    EFFECTS OF BARLEY STRAW EXTRACT ON GROWTH OF FIVE SPECIES OF PLANKTONIC ALGAE

    JOURNAL OF PHYCOLOGY, Issue 2001
    Article first published online: 24 SEP 200
    Holz, J. C.1, Fessler, C. J.2, Severn, A. A.1 & Hoagland, K. D.1 1School of Natural Resource Sciences, University of Nebraska, 103 Plant Industry Bldg., Lincoln, NE, 68583-0814; 2Biology Department, Nebraska Wesleyan University, 5000 St. Paul Ave., Lincoln, NE, 68504; Phone: 402-472-6648; Fax: 402-472-2964 The effects of exposure to barley straw extract and the timing of exposure on the growth of four common cyanophyte species and one species of green algae were investigated in two laboratory experiments. Clonal cultures of Anabaena cylindrica, Cylindrospermum sp., Gloeocapsa sp., Eucapsis sp., and Chlorella vulgaris were obtained from culture collections. In both experiments, the algae were cultured in Guillard's WC medium at 20 C on a 12:12 L/D photoperiod. In the first experiment, the algae were dosed with four concentrations of barley straw extract at the beginning of the experiment (day 0) and growth was monitored every second day using fluorometric detection of chlorophyll a for 14 d. In the second experiment, the algae were dosed with the same extract concentrations, but the extract was not added until the algae were in exponential growth phase (day 6). Both experiments also had control treatments (i.e. no extract) and each extract and control treatment was replicated five times. Growth of C. vulgaris was inhibited by all doses in both experiments, but inhibition was 22% greater when the extract was added on day 0. Growth Gleocapsa sp. was slightly inhibited by all doses when the extract was added on day 0, but not when it was added on day 6. No other species were inhibited, regardless of dose or timing of dose. The results of this study and other bioassay studies suggest that differential susceptibility to barley straw among algae is common and may reduce the effectiveness of barley straw as an algal control technique. [source]


    INVESTIGATION OF A COMPLEX PLANT EXTRACT FOR MILD TO MODERATE ERECTILE DYSFUNCTION IN A RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, PARALLEL-ARM STUDY

    BJU INTERNATIONAL, Issue 11 2010
    Elie Ghannam Nemr
    No abstract is available for this article. [source]


    EFFECTS OF PRUNE EXTRACT ON BLOOD PRESSURE ELEVATION IN STROKE-PRONE SPONTANEOUSLY HYPERTENSIVE RATS

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 2007
    Hiroko Negishi
    SUMMARY 1Prunes are recognized as a health food. They contain large amounts of phenolics and show high anti-oxidant activity. In this study, both hydroxyl radicals and superoxide anion were scavenged by prune extract in electron spin resonance (ESR) analysis. 2In angiotensin II challenged vascular smooth muscle cells (VSMCs) from stroke-prone spontaneously hypertensive rats (SHRSP), the reactive oxygen species (ROS) level was decreased in caffeic acid-treated cells compared with the control. 3After 5 weeks of prune extract treatment, the elevation of blood pressure in the prune extract-treated SHRSP was suppressed in comparison with the control group. 4Our findings suggest that prune extract may contribute to the primary prevention of cardiovascular diseases. [source]


    GINKGO BILOBA EXTRACT CAUSES DECREASE IN HEART RATE IN AGED SPONTANEOUSLY HYPERTENSIVE RATS

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 2007
    Y Kubota
    SUMMARY 1We previously reported that Ginkgo biloba extract (GBE) improves cardiovascular function in young spontaneously hypertensive rats (SHR). In the present study, changes in the cardiovascular parameters of aged SHR were examined following a 4-week diet of GBE. 2Feeding with GBE significantly decreased the heart rate and blood flow velocity in the tails of aged SHR. The contractile and relaxation responses were unchanged in isolated aortas and mesenteric arteries of aged SHR fed the GBE diet. The GBE diet did not influence the protein levels of endothelial nitric oxide synthase or soluble guanylyl cyclase in the aortas. 3These findings indicate that in aged SHR, the ingestion of GBE may cause bradycardia without a beneficial effect on the vascular relaxation response. Intake of GBE as a supplement in elderly hypertensive patients should be carefully monitored. [source]


    AMINO ACID AND FATTY ACID COMPOSITION OF AN AQUEOUS EXTRACT OF CHANNA STRIATUS (HARUAN) THAT EXHIBITS ANTINOCICEPTIVE ACTIVITY

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 3 2007
    ZA Zakaria
    SUMMARY 1The present study was performed in order to determine the amino acid and fatty acid composition of an aqueous extract of the freshwater fish Channa striatus, obtained by soaking (1 : 2, w/v) fresh fillets overnight in a chloroform : methanol (2 : 1, v/v) solvent, to elucidate the mechanism responsible for its antinociceptive activity and to clarify the relationship between the presence of the amino and fatty acids and the expected activity. 2The aqueous extract was found to contain all amino acids with the major amino acids glycine, alanine, lysine, aspartic acid and proline making up 35.77 0.58, 10.19 1.27, 9.44 0.56, 8.53 1.15 and 6.86 0.78% of the total protein, respectively. 3In addition, the aqueous extract was found to have a high palmitic acid (C16 : 0) content, which contributed approximately 35.93 0.63% to total fatty acids. The other major fatty acids in the aqueous extract were oleic acid (C18 : 1), stearic acid (C18 : 0), linoleic acid (C18 : 2) and arachidonic acid (C20 : 4), contributing 22.96 0.40, 15.31 0.33, 11.45 0.31 and 7.44,,0.83% of total fatty acids, respectively. 4Furthermore, the aqueous extract was demonstrated to possess concentration-dependent antinociceptive activity, as expected, when assessed using the abdominal constriction test in mice. 5It is concluded that the aqueous extract of C. striatus contains all the important amino acids, but only some of the important fatty acids, which are suggested to play a key role in the observed antinociceptive activity of the extract, as well as in the traditionally claimed wound healing properties of the extract. [source]


    GREEN TEA EXTRACT IMPEDES DYSLIPIDAEMIA AND DEVELOPMENT OF CARDIAC DYSFUNCTION IN STREPTOZOTOCIN-DIABETIC RATS

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 12 2006
    PV Anandh Babu
    SUMMARY 1The efficacy of green tea extract (GTE) on serum and cardiac lipids was investigated in streptozotocin (STZ)-diabetic rats. 2Diabetes was induced in rats by a single intraperitoneal injection of STZ (60 mg/kg bodyweight). Six weeks after the induction of diabetes, GTE was administered orally for 4 weeks (300 mg/kg bodyweight daily). Bodyweight, heart weight, heart weight : bodyweight ratio, blood glucose, serum and cardiac lipids were determined in experimental rats. 3In diabetic rats, there was a significant decrease in bodyweight with an increase in heart weight : bodyweight ratio and blood glucose. Diabetic rats had significantly increased serum levels of cholesterol, triglycerides, free fatty acids and low-density lipoprotein,cholesterol (LDL-C) and decreased levels of high-density lipoprotein,cholesterol (HDL-C). In the hearts of diabetic rats, there was a significant increase in cholesterol, triglycerides and free fatty acids levels, with an increase in lipoprotein lipase activity. 4The administration of GTE to diabetic rats resulted in significant recovery in bodyweight, heart weight : bodyweight ratio and blood glucose levels. The administration of GTE reduced cholesterol, triglyceride, free fatty acid and LDL-C levels, and increased HDL-C levels, in the serum of diabetic rats. In addition, GTE decreased cholesterol, triglyceride, free fatty acids levels and lipoprotein lipase activity in the myocardium of diabetic rats. These beneficial effects of GTE are ascribed to its antihyperglycaemic and hypolipidaemic activity. In conclusion, green tea can reduce the risk of cardiovascular disease in diabetes with a significant improvement in lipid metabolism. [source]


    THERAPEUTIC EFFECT OF GREEN TEA EXTRACT ON ADVANCED GLYCATION AND CROSS-LINKING OF COLLAGEN IN THE AORTA OF STREPTOZOTOCIN DIABETIC RATS

    CLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 4 2006
    Pon Velayutham Anandh Babu
    SUMMARY 1The therapeutic effect of green tea extract (GTE) on the aortic collagen content and its characteristics were investigated in streptozotocin diabetic rats. 2Diabetes was induced in rats by a single intra peritoneal injection of streptozotocin (60 mg/kg bodyweight). Six weeks after diabetes induction, GTE was administered orally for four weeks (300 mg/kg bodyweight daily). Systolic blood pressure, blood glucose, anti-oxidant status, collagen content, extent of glycation, collagen linked fluorescence and aortic collagen solubility pattern were determined in experimental rats. 3At the end of the experimental period, there was a significant increase in the systolic blood pressure and blood glucose in diabetic rats. The lipid peroxides increased whereas glutathione and vitamin C levels were decreased in the serum of diabetic rats. The collagen content, extent of glycation, the advanced glycation end products (AGEs) and degree of cross-linking were increased in the aorta of diabetic rats. 4The oral administration of GTE to diabetic rats significantly reduced the systolic blood pressure and blood glucose. The level of lipid peroxides reduced and the content of glutathione and vitamin C increased in the serum of GTE treated diabetic rats. Green tea extract also impede the accumulation of aortic collagen, extent of glycation, formation of AGEs and cross-linking of collagen in diabetic rats. The antihyperglycemic, anti-oxidant and antiglycating effects of GTE ascribed for these beneficial effects. In conclusion, green tea may have therapeutic effect in the treatment of cardiovascular complications characterized by increased AGE accumulation and protein cross-linking associated with diabetes. [source]


    EVALUATION OF EXTRACTS FROM BAMBOO FOR BIOLOGICAL ACTIVITY AGAINST CULEX PIPIENS PALLENS

    INSECT SCIENCE, Issue 4 2004
    Hai-qun Cao
    Abstract The extracts from 7 species of bamboo were tested for larvicidal activity against Culex pipiens pallens. At the tested concentration, the extracts of selected bamboo had different degree of toxic effects on the fourth instar larvae of Culex pipiens pallens. Among them, the extracts of Pleioblastus juxianensis, Brachystachyum albostriatum, Phyllostachys platyglossa and Pleioblastus amarus were found to be effective with LC50values at 24 h of 30.65 mg/L, 53.94 mg/L, 41.21 mg/L and 54.49 mg/L respectively, against Culex pipiens pallens larvae. The extract of Pleioblastus juxianensis by Soxhlet method showed stronger activity than the extract obtained by interval-shaking, the LC50 of which were 30.65 mg/L and 48.34 mg/L, respectively. The diethyl ether extract of Pleioblastus juxianensis exhibited better larvicidal activity than the methanol extract and the petroleum ether extract. The results would help to provide the basis for the study of environment acceptable pesticide for mosquito control, and also help to comprehensively utilize the source of bamboo. [source]


    PHENOLIC COMPOUND CONTENT, ANTIOXIDANT AND RADICAL-SCAVENGING PROPERTIES OF METHANOLIC EXTRACTS FROM THE SEED COAT OF CERTAIN THAI TAMARIND CULTIVARS

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 5 2010
    MANEEWAN SUKSOMTIP
    Methanolic extracts from the seed coats of five major tamarinds (Srichomphu, Sithong-nak, Sithong-bao, Priao-yak and Khanti) cultivated in Thailand were investigated for their content of phenolic compounds and their antioxidative properties. Antioxidative properties were evaluated by various different methods: scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical, anti-lipid peroxidation and reducing power assay. The phenolic compound contents were determined by spectrophotometric methods. Extract of Priao-yak with the highest tannin content showed the strongest reducing power, while extract of Khanti with the highest proanthocyanidin content revealed high scavenging ability on both DPPH and hydroxyl radicals. Stronger antioxidative activity measured by most assays was noted for the extract of Sithong-bao with a high content of total phenols, proanthocyanidin and tannins. The results suggest that specific phenolic constituents in the extract could be responsible for the different antioxidant properties observed in different cultivars. Furthermore, seed coat extract of Sithong-bao may be a potential source of natural antioxidant to be developed into nutraceuticals. PRACTICAL APPLICATIONS Components of Tamarindus indica L., a tree indigenous to India and South-East Asia, have long been used as a spice, food component and traditional medicine. According To traditional medicine, the tamarind pulp is used as a digestive, carminative, laxative, expectorant and blood tonic; the seeds are used as an anthelmintic, antidiarrheal and emetic. In addition, the seed coat is used to treat burns and aid wound healing as well as as an antidysenteric. Recent studies have demonstrated polyphenolic constituents with more potent antioxidant and anti-inflammatory activities of T. indica seed coat extract. Therefore, seed coat extracts of T. indica have economic potential for development into health promotion products as well as natural preservatives to increase the shelf life of food by preventing lipid peroxidation. [source]


    ANTIOXIDANT PROPERTIES OF WATER EXTRACTS FROM PARCHING GREEN TEA

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2010
    SHENG-DUN LIN
    ABSTRACT Cold and hot water extracts (2, 6 and 10%) were prepared from parching green tea and its antioxidant properties studied and potential antioxidant components determined. Yields of hot water extracts (17.53,28.63%) were significantly higher than those of cold water extracts (13.34,16.14%). The half maximal effective concentration (EC50) values in antioxidant activity and reducing power were 2.17,2.75 and 0.22,0.30 mg/mL, respectively. Scavenging abilities on 1,1-diphenyl-2-picrylhydrazyl radicals were comparable. EC50 values in scavenging ability on hydroxyl radicals and chelating ability on ferrous ions were 3.31,4.54 and 1.63,3.09 mg/mL, respectively. Contents of total phenols were 220.52,339.83 mg/g whereas those of total catechins in cold and hot water extracts were 130.22,146.28 mg/g and 136.40,191.33 mg/g, respectively. Based on the results obtained, hot water extracts were more effective in antioxidant activity, reducing power and scavenging ability on hydroxyl radicals but less effective in chelating ability on ferrous ions. PRACTICAL APPLICATIONS Tea is one of popular drinks in the world. The consumption of green tea is especially popular in Asia, mainly for its health benefits. Parched tea is a Chinese style green tea, which is different from the Japanese style steamed tea. Recently, the tea prepared by brewing tea leaves in cold water has become a new choice in Taiwan in addition to traditionally hot water-brewed tea. Results from this research, the cold and hot water extracts of green tea are good antioxidant. Besides, green tea is also reported to reduce serum cholesterol levels and inhibit hypertension, mutagenesis, and tumourigenesis in several experiments in vitro and in vivo. Therefore, the extract of green tea has the potential to be developed into new health foods, and the cold brewing would be a new alternative way to make a tea. [source]


    ESR SPECTROSCOPY INVESTIGATION OF ANTIOXIDANT ACTIVITY AND PROTECTIVE EFFECT ON HYDROXYL RADICAL-INDUCED DNA DAMAGE OF ENZYMATIC EXTRACTS FROM PICRORRHIZA KURROA

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2008
    SOUNG-HEE CHOI
    ABSTRACT The potential antioxidant activity of enzymatic extracts from Picrorrhiza kurroa was evaluated on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, hydroxyl radical and alkyl radical-scavenging activities using an electron spin resonance spectrometer (JEOL Ltd., Tokyo, Japan). P. kurroa was enzymatically hydrolyzed by seven carbohydrases and five proteases to prepare water-soluble extracts. The DPPH radical-scavenging activities of the pancreatic trypsin and Amyloglucosidase (AMG) (artificial carbohydrase by Novozyme Nordisk, Bagsvaerd, Denmark) extracts from P. kurroa were the highest among protease and carbohydrase extracts, and 50% inhibitory concentration (IC50) values were 35.58 and 29.03 g/mL, respectively. The hydroxyl radical-scavenging activity of the Protamex and Viscozyme extracts from P. kurroa were the highest scavenging activities, and the IC50 values were 0.46 and 1.89 mg/mL, respectively. In addition, the Protamex and Maltogenase extracts from P. kurroa showed the highest alkyl radical-scavenging activities, and the IC50 values were 18.03 and 10.66 g/mL, respectively. The protective effect of the Protamex extracts from P. kurroa on DNA damage which was free radical-induced was 92% at 3 mg/mL. These results indicate that enzymatic extracts of P. kurroa show potent antioxidant activity. PRACTICAL APPLICATIONS Picrorrhiza kurroa could be used to produce protein and carbohydrate extracts with antioxidative activity. Many industrial commercial enzymes such as Promozyme, Celluclast 1.5 L FG, Maltogenase L, Viscozyme L, Termamyl SC, Dextrozyme E, AMG 300 L, Protamex, Flavourzyme 500 MG, Neutrase 0.8 L, Pancreatic Trypsin and Alcalase 2.4 L could be also used to attain the extracts processing the high antioxidative activity. The extracts can be used as natural antioxidants. [source]


    CHRACTERIZATION AND 1,1-DIPHENYL-2-PICRYLHYDRAZYL RADICAL SCAVENGING ACTIVITY OF METHANOL AND SUPERCRITICAL CARBON DIOXIDE EXTRACTS FROM LEAVES OF ADINANDRA NITIDA

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2008
    BENGUO LIU
    ABSTRACT Leaves of Adinandra nitida are consumed in southern China as health tea (Shiyacha) and as herbal medicine. In this study, the methanol and supercritical fluid extracts from leaves of A. nitida were obtained by traditional solvent extraction and supercritical carbon dioxide extraction, respectively. Both the extracts showed high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. By using ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), nuclear magnetic resonance, electrospray ionization mass spectrometry (ESI-MS), high-performance liquid chromatography-ESI/MS, the main bioactive constituents in the methanol extract (ME) were identified as camellianin A, camellianin B, apigenin. By analysis of gas chromatography-mass spectrometry, a total of 16 compounds accounting for 98.79% of the supercritical fluid extract (SFE) were identified as ,-sitosterol, vitamin E, ,-tocopherol and so on. These compounds found in ME and SFE could contribute to the DPPH radical scavenging performance of the extracts in this study. PRACTICAL APPLICATION Adinandra nitida is a kind of particular wild plant in South China. Few reports have been published about it in the world. In this study, the methanol and supercritical fluid extracts from leaves of A. nitida were respectively obtained by two kinds of industrially significant methods, traditional solvent extraction and supercritical carbon dioxide extraction. By using ultraviolet-visible spectrometry (UV), infrared spectrometry (IR), nuclear magnetic resonance, electrospray ionization mass spectrometry (ESI-MS), high-performance liquid chromatography-ESI/MS, gas chromatography-MS, the main bioactive constituents in the two extracts were identified as flavonoids and plant sterols. Both the extracts showed high 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and this activity of the flavonoid-rich methanol extract was 10 times more than that of butylated hydroxytoluene. These results showed that leaves of A. nitida is a new kind of natural antioxidant-rich, flavonoid-rich plant source with great commercial interest in the food and phytopharmaceutical market. [source]


    ANALYSIS OF ANTIOXIDANT POTENTIAL USING A BIOASSAY BASED ON OXIDATION OF 5-(2 AMINOETHYL)BENZENE-1,2,4-TRIOL FOR SCREENING PLANT FOOD EXTRACTS

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 4 2007
    YU YAO
    ABSTRACT Neurotoxic products including reactive quinones and oxygen species such as H2O2 are generated upon oxidation of 4-(2-aminoethyl)-1,2-benzenediol (dopamine) and 5-(2-aminoethyl)benzene-1,2,4-triol (6-OH dopamine). Moreover, neurotoxicity of 6-OH dopamine and related oxidative stress may be increased in the presence of cytochrome c (Cytc) that is released from its normal mitochondrial location. A Cytc-enhanced 6-OH dopamine oxidation reaction is presented as a model bioassay for identifying possible neuroprotective food antioxidants and their metabolites. A concentration-dependent effect was observed for Cytc upon 6-OH dopamine oxidation. Fruit/vegetable extracts, prepared from Fragaria and Pisum, were tested by this assay; a three- to fourfold greater antioxidant potency was observed for Fragaria. The results were discussed in terms of the content for antioxidant phytochemicals. In addition, potencies for these dietary antioxidants were compared to those of a related assay based on N,N,N,,N,-tetramethyl-1,4-phenylene-diamine peroxidation. PRACTICAL APPLICATIONS The bioassay presented herein is intended to be used for screening the antioxidant activities of purified dietary compounds and their in vivo metabolites, as well as crude plant extracts and other food preparations. Examples are provided by the use of fruit and vegetable extracts; and these activities arecompared with those of purified phytochemicals. Because of the potential relevance of this assay to some neurological disorders and mitochondrial dysfunctions, phytochemicals and food extracts with strong protective activities in this initial screen may be good candidates for further analyses (biochemical, cellular and animal experiments) related to such disorders e.g., related to dopaminergic neurodegeneration as discussed below. [source]


    INHIBITION OF HELICOBACTER PYLORI BY PHENOLIC EXTRACTS OF SPROUTED PEAS (PISUM SATIVUM L.)

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 1 2006
    CHIA-YU HO
    ABSTRACT Infection by Helicobacter pylori is associated with gastric and duodenal ulcers. Conventional treatments to eradicate it have side-effects such as diarrhea and dizziness. The excessive use of antibiotics could also lead to antibiotic-resistant bacteria. The use of plant phenolic phytochemicals can be an alternative because of their health benefits due to both antioxidant activity and antimicrobial activity. The pea (Pisum sativum), the world's second most important pulse crop, produces phenolic phytochemicals with antimicrobial potential. Because the synthesis of phenolic compounds increases with stress, we investigated the anti- H. pylori effectiveness of extracts from pea sprouts, germinated in the dark condition following treatment with either distilled water or acetyl salicylic acid. The peas were germinated for 8 days and the sprouted samples were measured for total soluble phenolic content, antioxidant and guaiacol peroxidase activity. Subsequently, the sprout extracts were tested for anti- H. pylori activity using the agar diffusion method and the effective dose was determined based on phenolic content. The results showed that both acetyl salicylic acid-treated and untreated pea sprouts at days 5 and 8 had anti- H. pylori activity. The minimum volume for inhibition was 50 ,L of extracts. The inhibitory effects were dose dependent. From this study, the potential to use natural phenolic phytochemicals from pea sprouts to control H. pylori was found to be promising. This provides a strategy and foundation to design legume phenolics as functional ingredients against H. pylori. [source]


    CLONAL HERBAL EXTRACTS AS ELICITORS OF PHENOLIC SYNTHESIS IN DARK-GERMINATED MUNGBEANS FOR IMPROVING NUTRITIONAL VALUE WITH IMPLICATIONS FOR FOOD SAFETY

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 3 2002
    PATRICK McCUE
    ABSTRACT Plant phenolics are secondary metabolites that confer beneficial properties to the plants that produce them. Extracts made from plants that produce these phytochemicals are increasingly being recognized for their antimicrobial properties. In this study, we investigated extracts made from high-phenolics-producing clonal lines of oregano and thyme for potential as elicitors of phenolic antioxidant production in dark-germinated mungbean (Vigna radiata,). Mungbean was dark-germinated under the rationale that any energy stored in the bean seed in the form of starch may potentially be utilized for enhanced phenolics production, since without a light source the dark-germinated seedling may not stimulate the development of photosynthetic components. Wafer-based herb extracts showed the greatest ability to stimulate phenolic content in dark-germinated mungbeans. Three of the oregano extracts were investigated further and showed an ability to stimulate glucose-6-phosphate dehydrogenase (G6PDH), guaiacol peroxidase (GPX), and antioxidant activity. These results suggest that the extracts contain an active elicitor that stimulates phenolic antioxidant content, as well as activity of the pentose-phosphate pathway. In addition, the results of this study suggest that extracts of high-phenolics-producing clonal plants may have potential in the food and agriculture industry as seed treatments for preventing bacterial infection in germinating sprouts by stimulating phenolic antioxidant-producing pathways, as well as for increasing the nutritional value of sprouts for human consumption. [source]


    ANTIOXBDANT PROPERTIES OF OREGANO (ORIGANUM VULGARE) LEAF EXTRACTS

    JOURNAL OF FOOD BIOCHEMISTRY, Issue 6 2000
    GIOVANNA CERVATO
    ABSTRACT We tested the antioxidant properties of both aqueous and methanolic extracts of oregano (origanum vulgare) They proved to be effective in the inhibition of all phases of the peroxidative process: first neutralizing free radicals (superoxide anion, hydroxyl radical and 1,1-diphenyl-2-picrylhydrazyl radical), then blocking peroxidation catalysis by iron (through iron-chelating and iron-oxidizing properties), and finally through interruption of lipid-radical chain reactions (chain-breaking activity). Their anti-glycosylation activity was also effective. The glycosylation oflipoproteins is directly related to their peroxidation. The amount of extract used in our experiments was obtained from 0.1,1 mg of dried leaves, amounts far less than those normally used in the Mediterranean diet. [source]


    EVALUATION OF GLOBAL YIELD, COMPOSITION, ANTIOXIDANT ACTIVITY AND COST OF MANUFACTURING OF EXTRACTS FROM LEMON VERBENA (ALOYSIA TRIPHYLLA[L'HRIT.] BRITTON) AND MANGO (MANGIFERA INDICA L.) LEAVES

    JOURNAL OF FOOD PROCESS ENGINEERING, Issue 2 2007
    CAMILA G. PEREIRA
    ABSTRACT In this work, the global yields, composition and antioxidant activity (AA) of extracts from lemon verbena (Aloysia triphylla) and mango (Mangifera indica) leaves obtained by different separation processes were determined. Lemon verbena extracts were obtained by supercritical fluid extraction (SFE), while mango leaf extracts were obtained by SFE, low-pressure solvent extraction (LPSE) and hydrodistillation. The extract's constituents were analyzed by thin-layer chromatography, gas chromatography/mass spectrometry and gas chromatography/flame ionization detector. The AA of the extracts was evaluated by the coupled reaction of , -carotene/linolenic acid. The cost of manufacturing (COM) was estimated for the SFE extracts. Higher global yields were obtained using SFE at 350 bar/45C (1.49%) for lemon verbena and LPSE (3.04%) for mango. The AAs of the extracts were larger than that of the , -carotene for both plants. The minimum values of COM were U.S.$26.96 and 52.45/kg of extract for lemon verbena and mango, respectively. [source]


    ANTIBACTERIAL ACTIVITY AND CHEMICAL CONSTITUTIONS OF OLEA EUROPAEA L. LEAF EXTRACTS

    JOURNAL OF FOOD PROCESSING AND PRESERVATION, Issue 3 2010
    MIHRIBAN KORUKLUOGLU
    ABSTRACT The in vitro antimicrobial activity of aqueous, acetone, diethyl ether and ethyl alcohol extracts of olive leaves (Olea europaea L.) was studied. The aqueous extract of olive leaves had no antibacterial effect against the test microorganisms, whereas acetone extract showed inhibitory effect on Salmonella enteritidis, Bacillus cereus, Klebsiella pneumoniae, Escherichia coli, Enterococcus faecalis, Streptococcus thermophilus and Lactobacillus bulgaricus. Furthermore, the antimicrobial activities of some phenolic compounds against microorganisms were tested. The most effective compound was found to be oleuropein while syringic acid was found ineffective. The characterization of phenolic compounds in different extracts determined by high performance liquid chromatography-air pressure chemical ionization-mass spectrometry detector (HPLC-APCI-MSD GC-MS) gas chromatography-mass spectrometry (GC-MS). The acetone and the ethyl alcohol extracts had the most and the least oleuropein content, respectively. PRACTICAL APPLICATIONS In recent years the extracts of many plant species have become popular, and attempts to characterize their bioactive principles have gained speed for many pharmaceutical and food-processing applications. Especially, antimicrobial properties of plants have revived as a consequence of current problems associated with the use of chemical preservatives. Because of consumers' negative perspectives of synthetic preservatives, attention is shifting toward natural alternatives. The findings suggest that olive leaf extracts and their phenolic compounds have good potential as antibacterial substances in food preservation as they may be more acceptable to consumers and the regulatory agencies in comparison with synthetic chemical compounds. [source]


    INFLUENCE OF SUPERCRITICAL CARBON DIOXIDE AND METHANOLIC EXTRACTS OF ROSEMARY ON OXIDATION AND SENSORY PROPERTIES OF WHEAT GERM OIL

    JOURNAL OF FOOD QUALITY, Issue 6 2009
    OZLEM YESIL-CELIKTAS
    ABSTRACT Both supercritical CO2 and methanolic extracts from the leaves of rosemary (Rosmarinus officinalis) harvested from three different locations of Turkey at four different times of the year were added at a concentration of 100 mg/kg to wheat germ oil. Wheat germ oil samples were stored in an incubator for 10 days at 50C in order to promote oxidation and for the efficacy of the extracts for stabilization purposes to be examined. Degree of oxidation was determined by peroxide and p -anisidine values, which were performed every 2 days. Extracts from Mersin and Canakkale regions performed better results. Additionally, June and September harvests had lower peroxide values. According to the descriptive sensory analysis, both locations and extraction methods were found to effect flavor. Some flavor attributes, such as wheatlike/starchy, fishy and rubbery/metallic changed during storage regardless of locations and extraction methods. Supercritical CO2 extracts performed better results in terms of both oxidation and sensory properties. PRACTICAL APPLICATIONS From the perspective of the food industry, wheat germ oil stabilized with a natural antioxidant such as rosemary can be marketed as a functional product that can create a niche. Rosemary extracts containing higher amounts of rosmarinic acid and carnosic acid should be preferred in order to provide a better shelf life of an edible oil such as wheat germ oil. [source]


    COMBINATION WITH PLANT EXTRACTS IMPROVES THE INHIBITORY ACTION OF DIVERGICIN M35 AGAINST LISTERIA MONOCYTOGENES

    JOURNAL OF FOOD QUALITY, Issue 1 2008
    ABDEL-MAJEED ZOUHIR
    ABSTRACT The susceptibility of 11 strains of Listeria monocytogenes to divergicin M35, a bacteriocin produced by Carnobacterium divergens strain M35, and to aqueous extracts of garlic, onion, oregano, red chili and black pepper at 30 and 10C, was evaluated using a microdilution assay. The susceptibility of divergicin-resistant strains to combinations of these agents was also evaluated. Three strains were resistant to divergicin M35 (>500 g/mL) at 30C but were more susceptible at 10C. Garlic gave the most inhibitory plant extract, followed by onion, while oregano, red chili and black pepper extracts were less active at both temperatures. Garlic extract and divergicin M35 combined or with other extracts increased inhibitory activity against the divergicin-resistant strains. The garlic/divergicin combination was the most effective at inhibiting these strains and was bactericidal at both temperatures. Log-phase cells were the most susceptible to the garlic/divergicin combination. Stationary-phase cells were much more resistant at both incubation temperatures. Furthermore, the effect of the garlic/divergicin combination at inhibiting divergicin-resistant L. monocytogenes in a food system was also studied using cold-smoked salmon as a food model. Results indicated that this combination could efficiently reduce the viability of L. monocytogenes in smoked salmon stored at 10C. PRACTICAL APPLICATIONS There is increasing popularity worldwide for chemical preservative-free, ready-to-eat and minimally processed seafood with low salt, fat and sugar content. Bacteriocins produced from lactic acid bacteria can have a potential application to prolong the shelf life of cold-smoked salmon. Also, plant and spice extracts have been shown to contain antibacterial substances with potential for application in foods. Thus, this research explores the combination of divergicin M35, a bacteriocin produced by Carnobacterium divergens strain M35, and aqueous extracts of garlic, onion, oregano, red chili and black pepper to inhibit Listeria monocytogenes and to prolong the shelf life of cold-smoked salmon. [source]


    INHIBITION OF FOODBORNE PATHOGENS AND SPOILING BACTERIA BY ESSENTIAL OIL AND EXTRACTS OF ERIGERON RAMOSUS (WALT.) B.S.P.

    JOURNAL OF FOOD SAFETY, Issue 2 2009
    ATIQUR RAHMAN
    ABSTRACT The antibacterial potential of essential oil and methanolic extracts of Erigeron ramosus (Walt.) B.S.P. was evaluated. Thirty-one components representing 95.3% of the total oil were identified, of which ,-caryophyllene (24.0%), ,-humulene (14.5%), 1,8-cineole (9.0%), eugenol (7.2%), globulol (7.1%), caryophyllene oxide (5.2%), ,-cadinene (5.0%), ,-copaene (4.9%) and widdrol (2.0%) were the major components. The antibacterial activity of essential oil and methanolic extracts of E. ramosus was determined in vitro using the agar diffusion method and minimum inhibitory concentration determination test against 14 (seven gram-positive and seven gram-negative) foodborne bacteria. The essential oil (5 L/mL, corresponding to 1,000 ppm/disc), methanol extract and its different organic subfractions (7.5 L/mL, corresponding to 1500 ppm/disc) of E. ramosus displayed a great potential of antibacterial activity against all gram-positive bacteria: Staphylococcus aureus (ATCC 6538 and KCTC 1916), Listeria monocytogenes (ATCC 19116, ATCC 19118, ATCC 19166 and ATCC 15313) and Bacillus subtilis ATCC 6633 and four gram-negative bacteria: Pseudomonas aeruginosa KCTC 2004, Enterobacter aerogenes KCTC 2190 and Escherichia coli (0157:H7 ATCC 43888 and ATCC 8739). The zones of inhibition of different concentrations of essential oil and methanolic extracts against the tested bacteria were found in the range of 10.1,22.3 mm, and MIC values were recorded between 62.5 and 500 g/mL. PRACTICAL APPLICATIONS The use of essential oil and organic extracts of Erigeron ramosus (Walt.) B.S.P. as antibacterial agents will be suitable for applications on the food industry as natural preservatives or flavoring to control foodborne pathogens. They can be used as growth inhibitors of Listeria monocytogenes, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Enterobacter aerogenes and Pseudomonas aeruginosa, some important foodborne pathogens and spoiling bacteria. The main reason for their suitability is their natural origin, which consumers find comforting and which is beneficial for the environment, and the very low risk that pathogens will develop resistance to the mixture of components that make up the oil and extracts with their apparent diversity of antibacterial mechanisms. These beneficial characteristics could increase food safety and shelf life. [source]


    CHEMICAL CHARACTERIZATION AND ANTIFUNGAL ACTIVITY OF ORIGANUM ONITES L. ESSENTIAL OILS AND EXTRACTS

    JOURNAL OF FOOD SAFETY, Issue 1 2009
    MIHRIBAN KORUKLUOGLU
    ABSTRACT Essential oils (EOs) and extracts (methanol, acetone and diethyl ether) of fresh and dried oregano (Origanum onites L.) were used to determine the antifungal effect on Alternaria alternata, Aspergillus flavus (two strains), Aspergillus niger (two strains), Aspergillus parasiticus, Fusarium semitectum, Fusarium oxysporum, Mucor racemosus and Penicillium roqueforti by disk diffusion methods. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) of all samples were determined. The antifungal activity of the fresh herb was greater than that of the dried herb. MIC values for fresh and dried methanol extracts were 150,950 g/mL and 750,950 g/mL, respectively. MFC values for methanol extracts were determined between 300 and 1200 g/mL for fresh oregano and between 750 and 1100 g/mL for dried oregano. The EOs of fresh and dried oregano totally inhibited test fungi. EOs produced the lowest MIC and MFC values: 8.5 g/mL and 9.0 g/mL, respectively (P < 0.005). The highest extract activity was exhibited by fresh oregano against A. alternata (24 mm) followed by P. roqueforti (20 mm). The greatest total antifungal effect was observed from methanol extracts. The chemical composition of fresh oregano EO and extracts was examined using gas chromatography-mass spectrometry (GC-MS). Over 80 volatiles were detected, of which 42 were positively identified by matching both MS fragmentation patterns with standardized retention characteristics. p-Cymene, thymol and carvacrol were the most prominent, followed by ,-pinene, camphor and borneol. PRACTICAL APPLICATIONS In the past decade interest in natural antimicrobial plant extracts has been growing. Various plants have historically been used for the purposes of food preservation and flavor enhancement as well as medicinal purposes. An example is oregano, the leafy part of the plant belonging to the Labiatae family. It has been used to improve the flavor and the organoleptic properties of many foods from numerous cultures. It has also been used to prolong the storage life of foods probably because of antifungal properties. The preservative nature of fresh oregano has been employed in many food applications, including meat and fish products, as well as in pharmaceuticals, alternative medicines and natural therapies. [source]


    HIGH-RESOLUTION MAGIC ANGLE SPINNING NMR ANALYSIS OF WHOLE CELLS OF CHAETOCEROS MUELLERI (BACILLARIOPHYCEAE) AND COMPARISON WITH 13C-NMR AND DISTORTIONLESS ENHANCEMENT BY POLARIZATION TRANSFER 13C-NMR ANALYSIS OF LIPOPHILIC EXTRACTS,

    JOURNAL OF PHYCOLOGY, Issue 3 2004
    Matilde S. Chauton
    Lipid composition in extracted samples of Chaetoceros muelleri Lemmermann was studied with 13C-NMR and distortionless enhancement by polarization transfer (DEPT) 13C-NMR, resulting in well-resolved 13C-NMR spectra with characteristic resonance signals from carboxylic, olefinic, glyceryl, methylene, and methyl groups. The application of a DEPT pulse sequence aided in the assignment of methylene and methine groups. Resonance signals were compared with literature references, and signal assignment included important unsaturated fatty acids such as eicosapentaenoic and docosahexaenoic and also phospholipids and glycerols. Results from the extracted samples were used to assign resonance signals in a high-resolution magic angle spinning (HR MAS) DEPT 13C spectrum from whole cells of C. muelleri. The NMR analysis on whole cells yielded equally good information on fatty acids and also revealed signals from carbohydrates and amino acids. Broad resonance signals and peak overlapping can be a problem in whole cell analysis, but we found that application of HR MAS gave a well-resolved spectrum. The chemical shift of metabolites in an NMR spectrum depends on the actual environment of nuclei during analysis, and some differences could therefore be expected between extracted and whole cell samples. The shift differences were small, and assignment from analysis of lipophilic extract could be used to identify peaks in the whole cell spectrum. HR MAS 13C-NMR therefore offers a possibility for broad-range metabolic profiling directly on whole cells, simultaneously detecting metabolites that are otherwise not detected in the same analytical set up and avoiding tedious extraction procedures. [source]