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Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM  + 10?7, IVM  + 10?9, IVM  + 10?11) and culture media (Experiment 2; Control, IVC  + 10?7, IVC  + 10?9, IVC  + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10?9, IVC  + 10?9, IVM /IVC  + 10?9). In Experiment 1, maturated oocytes from Control and IVM  + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10?7 (43.5%; 56.7%) and IVC  + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10?9. Reactive oxygen species production was greater in the IVM /IVC  + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   
3.
Flavonol glycosides from Aconitum vulparia   总被引:1,自引:0,他引:1  
Fico G  Braca A  Morelli I  Tomè F 《Fitoterapia》2003,74(4):420-422
The isolation of five flavonol glycosides (1-5) from the flowers of Aconitum vulparia is reported, together with the 1H- and 13C-NMR spectral data in CD(3)OD of compound 3 and 5.  相似文献   
4.
A new kaurane diterpene dimer, 15-oxozoapatlin-13alpha-yl-10'alpha,16'alpha-dihydroxy-9'alpha-methyl-20'-nor-kauran-19'-oic acid gamma-lactone-17'-oate (1), together with the known 13-hydroxy-15-oxozoapatlin (2), 10alpha,13alpha,16alpha,17-tetrahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (3), 2alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid (19,10)-lactone (4), 3alpha,10alpha,13alpha,16alpha,17-pentahydroxy-9alpha-methyl-15-oxo-20-nor-kauran-19-oic acid gamma-lactone (5), and 1beta,16alpha,17-trihydroxy-ent-kaurane (6) were isolated from the leaves of Parinari campestris and identified on the basis of detailed spectral analysis, including 2D NMR spectrometry and ESI-MS.  相似文献   
5.
A new acylated quercetin glycoside, quercetin 3-O-(2-t-p-coumaroyl)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside-7-O-beta-D-glucopyranoside (1), together with the known 3-(3,4-dihydroxyphenyl)lactic acid (2) were isolated from Ranunculus lanuginosus leaves and identified on the basis of detailed spectral analysis, including 2D-NMR spectrometry and ESI-MS.  相似文献   
6.
Two new compounds, 10-O-beta-D-glucopyranosyl aloenin (4) and 8-C-beta-D-glucopyranosyl-7-O-methyl-(R)-aloesol (6), were isolated from a commercial sample of Kenya aloe together with the known products aloenin (2), aloenin 2'-p-coumaroyl ester (3), aloenin aglycone (1), orcinol and acetylorcinol. All structures were determined or confirmed by spectral analyses.  相似文献   
7.
Fico G  Braca A  Tomè F  Morelli I 《Fitoterapia》2001,72(4):462-463
A new phenolic ester has been isolated from the seeds of Nigella damascena and the structure was established as 1-O-(2,4-dihydroxy)phenylacetyl glycerol (1) by 1H and 13C-NMR spectral data and EI-MS analysis.  相似文献   
8.
Braca A  Bilia AR  Mendez J  Morelli I 《Fitoterapia》2001,72(2):182-185
Dried leaves of Licania densiflora yielded five myricetin glycosides: myricetin 3'-methylether-3-O-glucoside (1), myricetin 3'-methylether-3-O-galactoside (2), myricetin 4'-methylether-3-O-rhamnoside (3), myricetin 3',5'-dimethylether-3-O-glucoside (4), and myricetin 3',5'-dimethylether-3-O-rhamnoside (5). Their structures were elucidated by spectroscopic methods including mono- and bi-dimensional NMR techniques.  相似文献   
9.
Water is the most important environmental constrain determining plant growth and fruit yield of olive tree plantations. Although olive trees are resilient to water-limited conditions of Mediterranean-type agroecosystems, crop yields may respond positively to any additional water up to a limit. A field experiment on olive trees was carried out with the aim to present guidelines for efficient management of irrigation scheduling, based on the relationship between plant water status and optimum fruit yield. These relationships were monitored during 2 years by analysing the influence of deficit irrigation strategies on vegetative development and yield parameters on mature modern-trained olive trees of cvs. Frantoio and Leccino. Treatments were: a non-irrigated control (rainfed) and three treatments that received seasonal water amount equivalent to 33, 66 and 100% of ETC in the period August–September, from the beginning of pit hardening to early fruit veraison. Atmospheric evaporative demand and soil moisture conditions were regularly monitored. Seasonal dynamics of plant water relations varied among treatments, and responded to variations in tree water status, soil moisture conditions and atmospheric evaporative demand. All measurements of tree water status were highly correlated with one another. Differences in yield between treatments indicated that water availability might have affected fruit weight before flowering or during the early stages of fruit growth rather than later in summer season. Results concerning crop yield revealed that irrigation of olive trees from the beginning of pit hardening could be recommended, at least in the experimental conditions of this study and in view of differences between genotypes.  相似文献   
10.
The essential oil obtained from the bark of Cinnamomum zeylanicum Blume (Lauraceae) and three of its main components, eugenol, (E)-cinnamaldehyde, and linalool (representing 82.5% of the total composition), were tested in two in vitro models of peroxynitrite-induced nitration and lipid peroxidation. The essential oil and eugenol showed very powerful activities, decreasing 3-nitrotyrosine formation with IC50 values of 18.4 microg/mL and 46.7 microM, respectively (reference compound, ascorbic acid, 71.3 microg/mL and 405.0 microM) and also inhibiting the peroxynitrite-induced lipid peroxidation showing an IC50 of 2.0 microg/mL and 13.1 microM, respectively, against 59.0 microg/mL (235.5 microM) of the reference compound Trolox. On the contrary, (E)-cinnamaldehyde and linalool were completely inactive.  相似文献   
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