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131.
Mattoli L Cangi F Maidecchi A Ghiara C Tubaro M Traldi P 《Journal of agricultural and food chemistry》2005,53(26):9860-9866
Immature bitter orange fruit and its extracts have been introduced into the market as an alternative to Ephedra in weight loss products. However, the safety of the immature bitter orange fruit and its extracts is a debated argument due to the presence of synephrine, a constituent known as a sympathomimetic agent. In this paper, we describe the development of a new, rapid, and simple liquid chromatography-electrospray ionization-tandem mass spectrometry method devoted to the quantitative determination of synephrine in bitter orange samples, containing a high quantity of synephrine, and sweet orange samples, known to contain a low level of synephrine but at the same time being one of the main synephrine sources in a normal human diet. Two bitter orange dry extracts containing 5 and 6% sSynephrine and 10 sweet orange samples have been analyzed. Between the sweet orange samples, six were fresh oranges and four were fresh-squeezed juices; in these samples, the synephrine levels ranged from 0.00128 to 0.00349%. 相似文献
132.
Epidemiological field controls in different Italian locations and seedling evaluations of the ‘Thatcher’ near-isogenic lines
(NILs) carrying the leaf rust resistance genes Lr1, Lr9, Lr24 and Lr47 were conducted during 5 years of testing. These genes confirmed their effectiveness in both field and greenhouse conditions.
Moreover a backcross program was carried out by using as recurrent parents the susceptible high-quality common wheat cvs ‘Bolero’,
‘Colfiorito’, ‘Serio’ and ‘Spada’ and the ‘Thatcher’ NILs carrying the above mentioned genes as donor parents. The progenies
of different cross combinations were selected by both resistance tests and marker assisted selection using molecular markers
(STS, SCAR, CAPS) closely linked to Lr genes: a complete cosegregation was observed between the resistance genes used and the corresponding molecular markers. 相似文献
133.
Alberto Nassi Luigi Quintieri Roberta Merlanti Francesca Pezzato Francesca Capolongo Marianna Pauletto Mauro Dacasto Mery Giantin 《Journal of veterinary pharmacology and therapeutics》2020,43(6):608-613
In humans, the cytochrome P450 3A (CYP3A) subfamily is involved in midazolam (MDZ) biotransformation into 1′- and 4-hydroxy metabolites, and the former serves as a probe for CYP3A catalytic activity. In veterinary species is still crucial to identify enzyme- and species-specific CYP substrates; thus, the aim of this study was to characterize MDZ oxidation in cattle liver. A HPLC-UV method was used to measure 1′- and 4-hydroxy MDZ (1′- and 4-OHMDZ, respectively) formation in cattle liver microsomes and assess the role of CYP3A by an immunoinhibition study. Moreover, MDZ hydroxylation was evaluated in 300 cattle liver samples and results were correlated with testosterone hydroxylation. Formation of both metabolites conformed to a single-enzyme Michaelis–Menten kinetics. Values of Vmax and Km were 0.67 nmol/min/mg protein and 6.16 μM for 4-OHMDZ, and 0.06 nmol/min/mg protein and 10.08 μM for 1′-OHMDZ. An anti-rat CYP3A1 polyclonal antibody inhibited up to 50% and 94% 1′- and 4-OHMDZ formation, respectively. MDZ oxidation in liver microsomes was poorly correlated with testosterone hydroxylation. In conclusion, cattle metabolized MDZ to 1′-OHMDZ and 4-OHMDZ. The immunoinhibition results indicated a major contribution of CYP3As to 4-OHMDZ formation and the involvement of other CYPs in 1′-OHMDZ production, paving the way for further investigations. 相似文献
134.
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136.
Francesca Mercati Paula Domingo Rolando Pasquariello Cecilia Dall'Aglio Alessandro Di Michele Katia Forti Paolo Cocci Cristiano Boiti Lidia Gil Massimo Zerani Margherita Maranesi 《Reproduction in domestic animals》2020,55(1):29-37
Freeze-drying (FD) has been exhaustively tried in several mammalian species as an alternative technique to sperm cryopreservation, but few studies have been done in rabbits (Oryctolagus cuniculus). The main objective of this study was to compare the protective effect of various antioxidants added to EDTA medium on structural and functional components of FD rabbit spermatozoa and on their status of global DNA methylation. FD media used were composed of basic FD medium (10 mM Tris-HCl buffer and 50 mM NaCl) supplemented with either 50 mM EDTA alone (EDTA) or added with 105 µM of rosmarinic acid (RA, EDTA-RA) or 10 µM of melatonin (MLT, EDTA-MLT). The effect of each medium on the preservation of FD spermatozoon structure was evaluated with light and scanning electron microscopy (SEM). Global DNA methylation was quantified in all FD sperm samples as well as in fresh spermatozoa. Morphologically, fracture points were evidenced in the neck, mid and principal piece of the spermatozoon tail. No differences in spermatozoon fracture points were evidenced among FD treatments: intact spermatozoa were the largest (p < .01) category, whereas the most frequent (p < .01) injury was the neck fracture, resulting in tailless heads. At SEM, the head of spermatozoa showed a well-conserved shape and intact membrane in all treatments. DNA methylation status was the same in all FD treatments. In conclusion, supplementation of EDTA, EDTA-RA and EDTA-MLT during FD preserved rabbit sperm morphological integrity and methylation status as well. Therefore, the difficulty of getting viable offspring using FD semen is likely unrelated to the impact of the lyophilization process on DNA methylation and morphology of lyophilized spermatozoa. 相似文献
137.
Rodolfo Ballestrazzi Simona Rainis Francesca Tulli Arianna Bracelli 《Aquaculture International》2003,11(3):289-299
Two hundred and twenty rainbow trouts (IBW: 700 g) were randomly allotted to four tanks, with a male/female ratio of 0.56. Fish were fed for 168 d with four experimental diets containing herring oil, cod liver oil and coconut oil with the following inclusion rates: diet A: 12-1-0% respectively; diet B: 6-1-6%; diet C: 0-1-12%; diet D: 0-0-13%. Irrespective of the dietary treatment, weight gains of broodstocks were high (> 3 g/d) and FCR below 2. No significant difference was observed concerning the total amount of eggs spawn, egg average weight (82.5 mg/egg) and lipid content (5.4 mg/egg). However, the fatty acid profile of eggs was significantly affected by the dietary treatments. The content of unsaturated fatty acids, particularly the n-3 fatty acid series (EPA and DHA) significantly decreased with increasing levels of coconut oil in the diet. 相似文献
138.
Fraternale D Sosa S Ricci D Genovese S Messina F Tomasini S Montanari F Marcotullio MC 《Fitoterapia》2011,82(4):654-661
The topical anti-inflammatory, free radical scavenging and antifungal activities of essential oils and extracts of Commiphora erythraea (Ehrenb.) Engl. resin were investigated. The hexane extract significantly inhibited oedema when applied topically in Croton oil-induced ear oedema assay in mice. The same extract showed antioxidant activity in DPPH radical scavenging assay. A bioguided separation of the hexane extract led to the isolation of furanosesquiterpenoids 1 and 2 that showed a weak antifungal activity, while compounds 3-5 resulted to be antioxidant (EC50 4.28, 2.56 and 1.08 mg/mL, respectively) and anti-inflammatory (30, 26 and 32% oedema reduction, respectively). 相似文献
139.
Sabrina Palanti Giovanni Predieri Francesca Vignali Elisabetta Feci Antonella Casoli Elena Conti 《Wood Science and Technology》2011,45(4):707-718
Wood modification with siloxanes bearing amino groups with copper-linking function was carried out by a sol–gel process. Tetraethoxysilane
(TEOS) and 3-aminopropyltriethoxysilane (APTES) were the main components. Two different procedures were followed: a two-step
process (impregnation with the TEOS/APTES mixture followed by dipping into a copper sulphate solution) and a one-step process
(impregnation with a homogeneous sol mixture of TEOS, APTES and copper (II) chloride). The obtained materials were characterized
by infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis. The determination
of copper content before and after leaching was performed by atomic absorption spectroscopy. The efficacy against the brown
rot fungus Coniophora puteana was tested by an accelerated procedure. SEM analyses showed that silicon penetrated into wood, while copper is effectively
drawn into wood only in the one-step treatment. Copper fixation to the silica gel proved to be adequately strong. Both sol–gel
treatments gave good protection against Coniophora puteana. 相似文献
140.
Chinnici F Natali N Sonni F Bellachioma A Riponi C 《Journal of agricultural and food chemistry》2011,59(12):6575-6582
The color features and the evolution of both the monomeric and the derived pigments of red wines aged in oak and cherry 225 L barriques have been investigated during a four months period. For cherry wood, the utilization of 1000 L casks was tested as well. The use of cherry casks resulted in a faster evolution of pigments with a rapid decline of monomeric anthocyanins and a quick augmentation formation of derived and polymeric compounds. At the end of the aging, wines stored in oak and cherry barriques lost, respectively, about 20% and 80% of the initial pigment amount, while in the 1000 L cherry casks, the same compounds diminished by about 60%. Ethyl-bridged adducts and vitisins were the main class of derivatives formed, representing up to 25% of the total pigment amount in the cherry aged samples. Color density augmented in both the oak and cherry wood aged samples, but the latter had the highest values of this parameter. Because of the highly oxidative behavior of the cherry barriques, the use of larger casks (e.g., 1000 L) is proposed in the case of prolonged aging times. 相似文献