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41.
Application of enzymes to garlic prior to steam distillation/hydrodistillation resulted in a two fold increase in the yield of oil. The oil yield in case of cellulase, pectinase, protease and viscozyme pretreatment was in the range of 0.39–0.51%, as against 0.28% in a control sample by steam distillation, and in the range of 0.45–0.57% by hydrodistillation as against 0.31% in a control sample. Profiling of the garlic oil thus obtained was carried out by GC–MS. Di-2-propenyl trisulfide (52%) along with the corresponding di- and tetra-sulphides (11% and 5%) constituted the major portion of the oil. The other major flavour compounds identified were methyl 2-propenyl trisulfide (11.8%), vinyl dithiins (9.9%) and dithianes (4.1%). The studies demonstrate that enzymes facilitate the extraction of garlic oil, resulting in an increase in the yield of oil, with little change either in flavour profile or physicochemical properties of the oil. 相似文献
42.
Mahdieh Sharifi Ramyakrishna Pothu Rajender Boddula Ghasem Rezanejade Bardajee 《International Journal of Hydrogen Energy》2021,46(4):3220-3229
Due to the increasing demand for monitoring diseases such as rising heart rate, diabetes, and ocular disorders wearable and implantable biomedical devices seems too essential for patients not only in the hospital but also at home or during working time. Researchers mostly try to offer valuable information on the conditions of patients as non-invasive, by using comfort biomedical device with a minimum side effect. So, small and self-powered with high sensitivity biomedical devices are recommended, among different power sources that introduced for devices, biofuel cells would be produced as power source for a range of medical devices because of its capability to generate sufficient power output compared to the primary power source. The nature of the electrode reaction and the nature of the biochemical reactions are some of the important parameters that are considered for the classification of fuel cells. Enzymatic biofuel cells due to high activity at mild conditions widely applied in pacemaker; glucometer; and smart contact lenses when compared to other kinds of biofuel cells. On the other hand, short lifespan is one of important limitations in this type of biofuel cells. So, the easiest way to overcome these challenges is to apply non-enzymatic ones. Recent studies have attempted to issue novel method for fabrication of non-enzymatic biofuel cell in order to produce a new generation which are inexpensive, disposable, selective, and sensitive in properties. However, consideration of researchers to the development of self-powered biomedical devices by using body fluids or providing electricity storage is rising. 相似文献
43.
Maud Sabine Cansell Aurélie Battin Pascal Degrace Joseph Gresti Pierre Clouet Nicole Combe 《Lipids》2009,44(3):237-247
The study was undertaken to determine whether eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3),
esterified in phospholipids (PL) as liposomes or in triglycerides (TG) as oil, exhibited comparable fates in liver lipids
and whether these fates were associated with gene expressions related to fatty acid (FA) metabolism. PL and TG mixtures with
close contents in EPA and DHA were administered to rats over 2 weeks. Most relevant events occurred after 3 days for both
treatments. At that time, liposomes, compared with oil, increased the liver content in PL with a FA composition enriched in
n-6 FA, comparable in DHA and much lower in EPA. Moreover, liposomes increased the activity and mRNA levels of carnitine palmitoyltransferase
(CPT) I. In contrast, fish oil exerted opposite effects on CPT I and increased the genic expression of lipogenic enzymes.
Liposomes, unlike fish oil, apparently increased the mRNA levels of acyl-CoA oxidase and the activity of the peroxisomal FA-oxidising
system. Concomitantly, mRNA levels of hepatic lipoprotein receptors were increased with both diets, but intracellular proteins
involved in free FA uptake and lipid synthesis were up-regulated only with liposome-treated rats. The quasi absence of EPA
in hepatic PL of liposome-treated rats on the short term could result from increased β-oxidation activities through metabolic
regulations induced by more available free EPA and other PUFA. 相似文献
44.
Effect of enzymes on extraction of volatiles from celery seeds 总被引:2,自引:0,他引:2
Celery (Apium graveolens L.), belonging to the family Apiaceae, is widely used as a spice, in perfumery and pharmaceutical applications. It is reported to possess several nutraceutical attributes, such as anticoagulation activity of blood plasma and prevention of cardiovascular diseases. Effects of various enzymes on the extraction of volatile oil of celery are reported in the present study. The oil yield, after cellulase, pectinase, protease and viscozyme pretreatment, was in the range 2.2–2.3% as against 1.8% in a control sample, by steam distillation. Profiling of the celery oil thus obtained by GC–MS showed that limonene, the major terpene, increased from 63% to 82% with enzyme treatment. The other major flavour compounds identified were β-selinene (16–17%), butyl phthalide and sedanolide. The study demonstrated that enzymes facilitated the extraction of celery oil with increase in oil yield with little change in either flavour profile or physicochemical properties of the oil. 相似文献
45.
Leandro H. Andrade Patrícia B.Di. Vitta Roberto S. Utsunomiya Iracema H. Schoenlein-Crusius Andr L.M. Porto Joo V. Comasseto 《Applied catalysis. B, Environmental》2005,59(3-4):197-203
The action of different fungal strains and hydrolytic enzymes on the biotransformation of ethyl acetate constituent of laboratory wastes (mixtures of ethyl acetate–hexanes) was investigated. The studies using Aspergillus terreus SSP 1498 as biocatalyst, showed good results concerning the efficiency of ethyl acetate biotransformation (upto 99%) and quickness of the process (5 min). Novozym 435 was found to be the best lipase for the hydrolysis of ethyl acetate from the waste (85% biotransformation). 相似文献
46.
Muhammad Ibrahim Amin Ismail Sadeq Hasan Al-Sheraji Azrina Azlan Azizah Abdul Hamid 《Journal of Functional Foods》2013,5(4):1900-1908
The effects of a bambangan juice powder (BJP) drink on plasma vitamin and antioxidant enzyme levels and liver and kidney function were investigated. Thirty-two healthy subjects (12 male and 20 female) ages 24–28 years were recruited from the Faculty of Medicine and Health Sciences of University Putra Malaysia, Malaysia. Compared with consuming the placebo, consumption of the BJP drink daily for 9 weeks significantly increased the concentration of plasma β-carotene and ascorbic acid. Plasma total antioxidant status was increased, but liver and kidney functions were unaffected after consumption of the BJP drink. The consumption of a BJP drink resulted in a significant improvement in certain cardiovascular biochemical parameters and thus reduced the risk of cardiovascular disease. 相似文献
47.
A series of aqueous phase and soil-slurry phase microcosm studies were conducted on 2,4,6-trinitrotoluene (TNT) to obtain kinetic data for optimizing a treatment protocol using an enzyme extract from spinach (Spinacia oleracea). Crude extract was obtained by homogenization of fresh leaves with a buffered protease inhibitor, and employed as phytoremediation agent. Aqueous phase microcosms containing 20?mg/L TNT and soil–slurry microcosms containing 1 g of a characterized sandy loam soil contaminated with 2,500?mg/kg TNT and 1,000?mg/kg hexahydro-1,3,5-trinitro-1,3,5-triazine were dosed with fixed aliquots of extract and analyzed for TNT transformation over time. The TNT concentration was monitored using a colorimetric method for nitroaromatic compounds based on EPA Method 8515. Nitrate reductase activity of the applied crude extract was simultaneously quantified. The transformation of TNT was described by a pseudofirst-order reaction. Coupling kinetic rate information with enzyme activity allowed for estimation of a second-order rate constant with respect to activity. A rectangular hyperbola function normalized for enzyme activity described observed kinetic data based on enzyme saturation, similar to a Michaelis–Menten relationship. Pseudofirst-order rate constants for the aqueous phase and soil–slurry phase experiments were fit to this function. The maximum rate of reaction (kmax) for TNT transformation was 0.50 and 0.04?h?1 for aqueous phase and soil–slurry phase experiments, respectively, while respective half-saturation constants (Ksat*) were comparable in value at 0.63 and 0.28?U/μmol–NO2, respectively. A Hanes–Woolf plot of reaction velocity versus TNT concentration with and without soil suggests an uncompetitive inhibition mechanism may be affecting overall nitrate reductase efficacy. Temperature effects for both aqueous phase and soil–slurry phase microcosms followed the Arrhenius relationship with estimated activation energies of 54.7 and 26.1?kJ/mol, respectively. 相似文献
48.
Limited hydrolysis of soy proteins with endo- and exoproteases 总被引:6,自引:3,他引:3
Stephanie?JungEmail author Coralie?Roussel-Philippe Jenny?L.?Briggs Patricia?A.?Murphy Lawrence?A.?Johnson 《Journal of the American Oil Chemists' Society》2004,81(10):953-960
Changes in the native state and functional properties of soy protein achieved by limited proteolysis of soy flour were investigated. Different enzyme-to-substrate ratios (E/S) were used to obtain low (3–5%) and medium (5–10%) degrees of hydrolysis (DH). Six protease preparations (three with predominately exopeptidase activities and three with predominately endopeptidase activities) were evaluated, and their effects on solubility, emulsification capacity, SDS-PAGE profiles, and denaturation enthalpies were characterized. Endoproteases (Multifect® Neutral, Protex? 6L, and Multifect® P-3000) and exoproteases (Fungal Protease Concentrate, Experimental Fungal Protease #1, and Experimental Fungal Protease #2) yielded similar increases in soy protein solubility. The modifications to the soy peptide profile were similar for the three exoprotease mixtures at a 1% E/S ratio, whereas the extent of hydrolysis with Protex? 6L was more pronounced than with the two other endoproteases (Multifect® Neutral and Multifect® P-3000). The emulsification capacity of protease-modified soy flour declined regardless of DH and enzyme type (exo- or endoprotease). After hydrolysis to >4% DH, denaturation enthalpies of glycinin and β-conglycinin decreased significantly, whereas hydrolysis to lower DH did not affect these values. 相似文献
49.
Dr. Francesca Mancuso Prof. Laura De Luca Federica Bucolo Milan Vrabel Dr. Andrea Angeli Dr. Clemente Capasso Prof. Claudiu T. Supuran Rosaria Gitto 《ChemMedChem》2021,16(24):3787-3794
A current issue of antimicrobial therapy is the resistance to treatment with worldwide consequences. Thus, the identification of innovative targets is an intriguing challenge in the drug and development process aimed at newer antimicrobial agents. The state-of-art of anticholera therapy might comprise the reduction of the expression of cholera toxin, which could be reached through the inhibition of carbonic anhydrases expressed in Vibrio cholerae (VchCAα, VchCAβ, and VchCAγ). Therefore, we focused our interest on the exploitation of sulfonamides as VchCA inhibitors. We planned to design and synthesize new benzenesulfonamides based on our knowledge of the VchCA catalytic site. The synthesized compounds were tested thus collecting useful SAR information. From our investigation, we identified new potent VchCA inhibitors, some of them displayed high affinity toward VchCAγ class, for which few inhibitors are currently reported in literature. The best interesting VchCAγ inhibitor (S)-N-(1-oxo-1-((4-sulfamoylbenzyl)amino)propan-2-yl)furan-2-carboxamide ( 40 ) resulted more active and selective inhibitor when compared with acetazolamide (AAZ) as well as previously reported VchCA inhibitors. 相似文献
50.
M. Antonia Martínez-Anaya Teresa Jiménez 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1998,206(2):134-142
The textural properties of wheat doughs made with different commercial amylases, xylanases/pentosanases, lipases and glucose-oxidase,
singly and in mixed combinations, were investigated. Parameters from the texture profile analysis (TPA) and measurement of
stickiness (Chen and Hoseney test) were determined after mixing the dough and after it had rested for 3.5 h. Resting of doughs
led to softer and less cohesive doughs, with higher adhesive properties. Enzymes acted quickly and induced significant changes
in the textural properties of doughs immediately after mixing. The influence of enzymes continued during resting. Xylanases/pentosanases
substantially reduced dough consistency and increased stickiness, while addition of glucose-oxidase and specific lipases overcame
these effects. Strong correlations could be established between different TPA parameters and stickiness and bread quality
characteristics (i.e. volume, density and texture). Bread quality could be described by a single or multiple linear combination
of textural variables.
Received: 21 May 1997 / Revised version: 10 July 1997 相似文献