24 resultados para Crude extract

em Deakin Research Online - Australia


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The efficacy of trout oil (TO), extracted from trout offal from the aquaculture industry, was evaluated in juvenile Murray cod Maccullochella peelii peelii (25.4-0.81 g) diets in an experiment conducted over 60 days at 23.7-0.8 °C. Five isonitrogenous (48% protein), isolipidic (16%) and isoenergetic (21.8 kJ gm1) diets, in which the fish oil fraction was replaced in increments of 25% (0-100%), were used. The best growth and feed efficiency was observed in fish fed diets containing 50-75% TO. The relationship of specific growth rate (SGR), food conversion ratio (FCR) and protein efficiency ratio (PER) to the amount of TO in the diets was described in each case by second-order polynomial equations (P<0.05), which were: SGR=-0.44TO2+0.52TO+1.23 (r2=0.90, P<0.05); FCR=0.53TO2-0.64TO+1.21 (r2=0.95, P<0.05); and PER=-0.73TO2+0.90TO+1.54 (r2=0.90, P<0.05). Significant differences in carcass and muscle proximate compositions were noted among the different dietary treatments. Less lipid was found in muscle than in carcass. The fatty acids found in highest amounts in Murray cod, irrespective of the dietary treatment, were palmitic acid (16:0), oleic acid (18:1n-9), linoleic acid (18:2n-6) and eicosapentaenoic acid (20:5n-3). The fatty acid composition of the muscle reflected that of the diets. Both the n-6 fatty acid content and the n-3 to n-6 ratio were significantly (P<0.05) related to growth parameters, the relationships being as follows. Percentage of n-6 in diet (X) to SGR and FCR: SGR=-0.12X2+3.96X-32.51 (r2=0.96) and FCR=0.13X2-4.47X+39.39 (r2=0.98); and n-3:n-6 ratio (Z) to SGR, FCR, PER: SGR=-2.02Z2+5.01Z-1.74 (r2=0.88), FCR=2.31Z2-5.70Z+4.54 (r2=0.93) and PER=-3.12Z2-7.56Z+2.80 (r2=0.88) respectively. It is evident from this study that TO could be used effectively in Murray cod diets, and that an n-3:n-6 ratio of 1.2 results in the best growth performance in Murray cod.

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A membrane-bound, haemolytic phospholipase A2 (PLA2) activity was detected in clinical strains of Campylobacter concisus isolated from children with gastroenteritis. The clinical strains were assigned into two molecular groups (genomospecies) based on PCR amplification of their 23S rDNA. This calcium-dependent, heat-stable, haemolytic PLA2 activity was detected in strains from both genomospecies. A crude haemolysin extract (CHE) was initially prepared from cellular outer-membrane proteins of these isolates and was further fractionated by ultrafiltration. The haemolytic activity of the extracted fraction (R30) was retained by ultrafiltration using a 30 kDa molecular mass cut-off filter, and was designated haemolysin extract (HE). Both CHE and HE had PLA2 activity and caused stable vacuolating and cytolytic effects on Chinese hamster ovary cells in tissue culture. Primers for the conserved region of pldA gene (phospholipase A gene) from Campylobacter coli amplified a gene region of 460 bp in all tested isolates, confirming the presence of a homologous PLA gene sequence in C. concisus. The detection of haemolytic PLA2 activity in C. concisus indicates the presence of a potential virulence factor in this species and supports the hypothesis that C. concisus is a possible opportunistic pathogen.

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Field-scale remediation of oil-contaminated soils from the Liaohe Oil Fields in China was examined using composting biopiles in windrow technology. Micronutrient-enriched chicken excrement and rice husk were applied as nutrition and a bulking agent. The lipase activities of indigenous micro-organisms were analyzed, and three indigenous fungi with high lipase activities was identified. An inoculum consisting of the three indigenous fungi and one introduced (exotic) fungus was applied to four different types of oil-contaminated soils. The results showed that the inoculum of indigenous fungi increased both the total colony-forming units (TCFU) and increased the rate of degradation of total petroleum hydrocarbons (TPH) in all contaminated soils but at different rates. In sharp contrast to other studies, the introduction of exotic micro-organisms did not improve the remediation, and suggests that inoculation of oil-contaminated sites with nonindigenous species is likely to fail. On the other hand, indigenous genera of microbes were found to be very effective in increasing the rate of degradation of TPH. The degradation of TPH was mainly controlled by the compositions of aromatic hydrocarbons and asphaltene and resin. Between 38 to 57% degradation of crude oils (with densities ranging from 25,800 to 77,200 mg/kg dry weight) in contaminated soils was achieved after 53 days of operation. The degradation patterns followed typical first-order reactions. We demonstrate that the construction and operation of field-scale composting biopiles in windrows with passive aeration is a cost-effective bioremediation technology.

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The purpose of the current study is to evaluate the cardioprotective effects of purified Salvia miltiorrhiza extract (PSME) on myocardial ischemia/reperfusion injury in isolated rat hearts. Hearts were excised and perfused at constant flow (7 – 9 ml · min−1) via the aorta. Non-recirculating perfusion with Krebs-Henseleit (KH) solution was maintained at 37°C and continuously gassed with 95% O2 and 5% CO2. KH solution with or without PSME (100 mg per liter solution) was used after 30-min zero-flow ischemia for the PSME and control group, respectively. Left ventricular (LV) developed pressure; its derivatives, diastolic pressure, and so on were continuously recorded via a pressure transducer attached to a polyvinylchloride balloon that was placed in the left ventricle through an incision in the left atrium. PSME treated hearts showed significant postischemic contractile function recovery (developed pressure recovered to 44.2 ± 4.9% versus 17.1 ± 5.7%, P<0.05; maximum contraction recovered to 57.2 ± 5.9% versus 15.1 ± 6.3%, P<0.001; maximum relaxation restored to 69.3 ± 7.3% versus 15.4 ± 6.3%, P<0.001 in the PSME and control group, respectively). Significant elevation in end-diastolic pressure, which indicated LV stiffening in PSME hearts might have resulted from the excess high dose of PSME used. Further study will be conducted on the potential therapeutic value with lower dose of PSME on prevention of ischemic heart disease.

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In the current study, we compared purified Salvia miltiorrhiza extract (PSME) with Angiotensin-converting enzyme inhibitor, Ramipril, in in vitro experiments and also in vivo using animal model of myocardial infarction. PSME was found to have a significantly higher trolox equivalent antioxidant capacity which indicated a great capacity for scavenging free radicals. PSME could also prevent pyrogallo red bleaching and DNA damage.

After 2 weeks treatment with PSME or Ramipril, survival rates of rats with experimental myocardial infarction were marginally increased (68.2% and 71.4%) compared with saline (61.5%). The ratios of infarct size to left ventricular size in both PSME-and Ramipril-treated rats were significantly less than that in the saline-treated group. Activity of cardiac antioxidant enzyme superoxide dismutase (SOD) was significant higher while level of Thiobarbituric acid-reactive substances (TBARs) was lower in the PSME treated group. Purified and standardized Chinese herb could provide an alternative regimen for the prevention of ischemic heart disease.

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It has been well documented that oxidative stress is involved in stroke. Currently, many neuroprotective strategies have been targeted at molecules that are able to act as an oxidant to intervene with free-radical mediated apoptosis in the ischemic penumbra. In particular, natural products which contain antioxidant properties have undoubtedly efficacious for stroke treatment. In the current study, therapeutic effects of Ginkgo biloba extract (EGb) against cerebral protection in Wistar rats underwent middle cerebral artery occlusion (MCAO) was evaluated. A comparison study was conducted by using Losartan, an antihypertensive drug. Gene expression levels of pro-apoptotic genes (AT2 receptor, Fas, Bax and Bcl-xS) have shown to have significant reduction by EGb- and Losartan-treated groups as compared to vehicle group. Significant reduction of immunoreactivity of protein production of these genes, together with least nuclear green fluorescence observed in TUNEL, EGb, as an antioxidant drug, is concluded to have potent and promising therapeutic effect for stroke treatment.

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Ginkgo biloba is one of the most popular herbal medicines in the world, due to its purported pharmacological effects, including memory-enhancing, cognition-improving, and antiplatelet effects. When used in the elderly, Ginkgo has a high potential for interactions with cardiovascular drugs. This study aimed to investigate the effects of the standard Ginkgo biloba extract (EGB 761) treatment on the pharmacokinetics of propranolol and its metabolism to form Ndesisopropylpropranolol (NDP) in rats. We also examined the activity and expression of cytochrome P450 (CYP) 1A and other CYPs in rats treated with EGb 761 at 10 and 100 mg/kg/day for 10 days. A single oral dose of propranolol (10 mg/kg) was administered on day 11 and the concentrations of both propranolol and NDP were determined using validated liquid chromatography-mass spectrometry (LC-MS) methods. The levels of mRNA and protein of various CYPs were determined by RT-PCR and Western blotting analysis, respectively. Pretreatment of EGb 761 at 100 mg/kg, but not 10 mg/kg, for 10 days significantly reduced the area under the plasma concentration-time curve (AUC) and maximum plasma concentration (C max) of propranolol, whereas those values of NDP were significantly increased. CYP1A1, 1A2, 2B1/2, and 3A1 activities and gene expression in the rat liver were significantly increased in a dose-dependent manner by pretreatment with EGb 761. The ex-vivo formation of NDP in liver microsomes from rats pretreated with EGb 761 was markedly enhanced. The formation of NDP from propranolol in liver microsomes was significantly inhibited by α- naphthoflavone (ANF, a selective CYP1A2 inhibitor), but not by quinidine (a CYP2D inhibitor). These results indicated that EGb 761 pretreatment decreased the plasma concentrations of propranolol by accelerated conversion of parental drug to NDP due to induction of CYP1A2. EGb 761 pretreatment also significantly induced CYP2B1/2 and CYP3A1, suggesting potential interactions with substrate drugs for these two enzymes. Further study is needed to explore the potential for gingko-drug interactions and the clinical impact.

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Supercritical fluid extracts of New Zealand green-lipped mussels (NZGLM) have been suggested to have therapeutic properties related to their oil components. The large number of minor FA in NZGLM extract was characterized by a GC-CIMS/MS method that excels at identification of double-bond positions in FAME. The extract contained five major lipid classes: sterol esters, TAG, FFA, sterols, and polar lipids. The total FA content of the lipid extract was 0.664 g/mL. Fifty-three unsaturated FA (UFA) were fully identified, of which 37 were PUFA, and a further 21 UFA were detected for which concentrations were too low for assignment of double-bond positions. There were 17 saturated FA, with 14∶0, 16∶0, and 18∶0 present in the greatest concentration. The 10 n−3 PUFA detected included 20∶5n−3 and 22∶6n−3, the two main n−3 FA; n−3 PUFA at low concentrations were 18∶3, 18∶4, 20∶3, 20∶4, 21∶5, 22∶5, 24∶6, and 28∶8. There were 43 UFA from the n−4, n−5, n−6, n−7, n−8, n−9, n−10, n−11 families, with 16∶2n−4, 16∶1n−5, 18∶1n−5, 18∶2n−6, 20∶4n−6, 16∶1n−7, 20∶1n−7, 16∶1n−9, 18∶1n−9, and 20∶1n−9 being the most abundant. In general, we estimated that FAME concentrations greater than 0.05% (w/w) were sufficient to assign double-bond positions. In total, 91 FA were detected in an extract of the NZGLM, whereas previous studies of fresh flesh from the NZGLM had reported identification of 42 FA. These data demonstrate a remarkable diversity of NZGLM FA.

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This paper examines the unit root properties of crude oil production for 60 countries employing a range of panel data unit root tests for the period 1971 to 2003. The study first employs a number of panel data tests that do not accommodate structural breaks and then proceeds to apply the Lagrange Multiplier (LM) panel unit root test with one structural break. The results of the panel data tests without a structural break are inconclusive with at best mixed support for joint stationarity. The findings from the LM panel unit root test with a structural break, however, are conclusive, suggesting that for a world panel and smaller regional-based panels, crude oil and NGL production are jointly stationary.

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CPE is an aqueous extract of the edible micro alga Chlorella pyrenoidosa, which has been shown to have immunostimulatory effects in vivo. In the present study, CPE was evaluated for an ability to stimulate cytokine production by human peripheral blood mononuclear cells (PBMC). PBMC from healthy individuals were treated ex vivo for 24 hours with 1, 10 and 100 μg/mL CPE. This resulted in a marked increase in the level of IL-10, a regulatory cytokine, and strong stimulation of the T-helper-1 (Th1) cell cytokines, IFN-γ and TNF-α. In contrast, stimulation of representative T-helper-2 (Th2) cell cytokines, IL-4 and IL-13, was minor. CPE (1, 10 or 100 μg/mL) did not cause a proliferation of human PBMC suggesting that enhanced secretion of cytokines was not secondary to an increase in cell number. We conclude that CPE stimulation of human PBMC induces a Th1-patterned cytokine response and a strong anti-inflammatory regulatory cytokine response, observations that await confirmation in vivo.

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We screened seaweed species from Atlantic Canada for antidiabetic activity by testing extracts for α-glucosidase inhibitory effect and glucose uptake stimulatory activity. An aqueous ethanolic extract of Ascophyllum nodosum was found to be active in both assays, inhibiting rat intestinal α-glucosidase (IC50 = 77 μg/mL) and stimulating basal glucose uptake into 3T3-L1 adipocytes during a 20-minute incubation by about 3-fold (at 400 μg/mL extract). Bioassay-guided fractionation of the A. nodosum extract showed that α-glucosidase inhibition was associated with polyphenolic components in the extract. These polyphenolics, along with other constituents appeared to be responsible for the stimulatory activity on glucose uptake. However, attempts to further concentrate this activity through fractionation techniques were unsuccessful. A crude polyphenol extract (PPE), an enriched polyphenolic fraction (PPE-F1) and a polysaccharide extract (PSE) were prepared from commercial A. nodosum powder and administered to streptozotocin-diabetic mice for up to 4-weeks by daily gavage at 200 mg/kg body mass. PPE and PPE-F1 improved fasting serum glucose level in diabetic mice; however, the effect was only statistically significant at day 14. In addition, PPE-F1 was shown to blunt the rise in blood glucose after an oral sucrose tolerance test in diabetic mice. Mice treated with PPE and PPE-F1 had decreased blood total cholesterol and glycated serum protein levels compared with untreated diabetic mice, whereas PPE also normalized the reduction in liver glycogen level that occurred in diabetic animals. All 3 A. nodosum preparations improved blood antioxidant capacity.

On a établit une recherche d’un produit anti-diabétique, parmi les algues locales de la région Atlantique du Canada, en examinant la capacité d’un effet inhibiteur de l’enzyme α-glucosidase et une stimulation de l’incorporation cellulaire du glucose. Un extrait éthanol-aqueux de Ascophyllum nodosum nous a donné une activité positive chez les deux essais, une inhibition de l’α-glucosidase provenant de l’intestin du rat (IC50 = 77 μg/mL) et puis une stimulation triple, à une concentration de 400 μg/mL, de l’incorporation du glucose dans les adipocytes 3T3-L1 durant une période de 20 minutes. L’extrait de A. nodosum a été divisé, guidé par les résultats biologiques, et a ainsi démontré la présence d’éléments polyphénoliques associé à l’inhibition de l’α-glucosidase. Ces éléments polyphénoliques ainsi que d’autres semblent être responsables de l’incorporation stimulée du glucose. Il a été impossible de raffiner cette activité lors d’une division des composants. Un extrait brut polyphénolique (PPE), un extrait enrichi polyphénolique (PPE-F1) et puis un extrait polysaccharide (PSE) furent préparés d’une poudre commerciale de A. nodosum et utilisés dans une étude utilisant des souris, rendues diabétiques par injections de streptozotocin, traitées par un gavage journalier de l’extrait 200 mg/kg du poids corporel durant une période de 4 semaines. Le taux du glucose sanguin à jeun des souris fut moins élevé en présence des extraits qu’en leurs absence. Cependant, l’effet était seulement significatif au jour 14. Les résultats étant toutefois variables. En plus, lors d’un essai oral de la tolérance au sucrose chez la souris diabétique, l’extrait PPE-F1 a empêché l’augmentation du taux du glucose sanguin. Les extraits PPE et PPE-F1 ont réduit le taux de cholestérol sanguin et les niveaux de glycation des protéines en comparaison de ces niveaux en absence des extraits tandis que l’extrait PPE a présenté une réduction du niveau de glycogène du foie chez les souris diabétiques. Les trois extraits de A. nodosum ont tous amélioré la capacité antioxidante du sang.

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Roots of Asparagus racemosus were used as a source of inulin for the production of inulinase from Kluyveromyces marxianus YS-1. Root extract prepared at 10 kg/cm2 for 10 min showed the maximum production of inulinase. Various parameters of fermentation have been examined in order to improve overall enzyme yield. Inulinase yield of 40.5 IU/mL in an optimized medium containing inulin (3.5%), beef extract (0.5%), MnSO4 (0.5 mM), CoCl2 (0.05 mM), SDS (0.4 mM) and pH 6.5 at 30 °C under agitation (150 rpm) for 60 h has been obtained at shake flask level. After optimization the enzyme production has been increased 6.1 times at flask level. In a bioreactor (working volume 1 L) fermentation medium containing 4% inulin has shown maximum inulinase production (47.3 IU/mL) under optimized parameters of 200 rpm, 0.75 vvm aeration at 30 °C after 60 h.

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An aqueous extract of the edible microalga, Chlorella pyrenoidosa (CP) (1), has recently been tested for its immunomodulatory effects in a human clinical trial. Here, the CP extract was dialyzed and fractionated using Sephadex G 100 chromatography. The effects of a dialyzed aqueous CP extract, fraction 2, on mast cell mediator release in vitro and ovalbumin-induced allergic airway inflammation in vivo were examined. In vitro, treatment of mouse bone marrow-derived mast cells with 2 for 18 h significantly inhibited antigen (trinitrophenyl-BSA)-induced IL-5 production. In vivo, treatment of mice with 2 during ovalbumin sensitization and stimulation process significantly reduced eosinophil and neutrophil infiltration in the airways. Moreover, fractions obtained by size exclusion chromatography of 2 inhibited IgE-dependent cytokine GM-CSF production from human cord blood-derived mast cells. Taken together, these results suggest that 2 is composed of biopolymers with anti-allergic potential.

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An arabinogalactan was isolated from a hot water extract of freeze-dried cells of the green microalga, Chlorella pyrenoidosa. This hot water extract is a proprietary immunomodulator, with the trademark Respondin™ (ONC-107). The arabinogalactan was recovered from the ethanol-soluble fraction of the supernatant resulting from a process that involved controlled ethanol precipitation followed by size exclusion chromatography on Sephadex G-100, then Cetavlon precipitation. Sugar analyses, GC–MS data for (S)-2-octyl glycosides, and 1D and 2D NMR experiments established unambiguously that the repeating unit was →2)-α-l-Araf-(1→3)-[α-l-Araf-(1→4)]-β-d-Galp-(1→. This structure does not fit into any of the known classes of arabinogalactans. SEC/MALS experiments gave a molecular mass for the arabinogalactan isolated as 47 ± 4 kDa but the original structure was probably larger.