Dietary supplements containing bitter orange unripe fruit extract/
p-synephrine are consumed worldwide for lose weight. This study were conducted to determine the concentration of
p-synephrine in ...unripe fruits and leaves from
Citrus aurantium Lin,
C. sinensis Osbeck,
C. deliciosa Ten,
C. limon Burm and
C. limonia Osbeck, collected in Southern Brazil, and to evaluate the acute toxicity of
C. aurantium extract and
p-synephrine. A high performance liquid chromatographic method with diode array detector (HPLC-DAD) was optimized and validated for determination of
p-synephrine. The results indicate that all of analyzed samples present
p-synephrine in amounts that range from 0.012% to 0.099% in the unripe fruits and 0.029 to 0.438% in the leaves. Acute oral administration of
C. aurantium extracts (2.5%
p-synephrine, 300–5000
mg/kg) in mice produced reduction of locomotor activity,
p-synephrine (150–2000
mg/kg) produced piloerection, gasping, salivation, exophtalmia and reduction in locomotor activity, which was confirmed in spontaneous locomotor activity test. All the effects were reversible and persisted for 3–4
h. The toxic effects observed seem to be related with adrenergic stimulation and should alert for possible side effects of
p-synephrine and
C. aurantium.
Metabolomics profile of equine seminal plasma Bueno, Veronica LC; Bastos, Henrique BA; Larentis, Gustavo R ...
Journal of equine veterinary science,
June 2023, 2023-06-00, Letnik:
125
Journal Article
Recenzirano
Seminal plasma (SP) is the product of testes, epididymis, and accessory sex glands released during ejaculation, making up 98% of the volume of the stallion ejaculate. Analyzing the entire metabolome ...allows to assess the final products of the biological system metabolism. The present study aimed to investigate the metabolomics of stallion SP. Twenty-four Criollo stallions with a known reproductive history and ≥30 inseminated mares were once collected during the breeding season. Pregnancy rates (day 16 after artificial insemination) ranged from 20.2% to 95.6%. Two groups were formed: High Pregnancy (HP; pregnancy rate per cycle ≥50%), and Low Pregnancy (LP; pregnancy rate of ≤49%). Microscopic semen analysis was performed using a computer-assisted sperm analysis system. Membrane physical integrity was assessed by fluorescent probes, and the hypoosmotic test analyzed membrane functional integrity. After centrifugation at 400xg for 10min centrifugation, SP plasma was transferred to a 2mL microcentrifuge tube and centrifuged again (10.000xg, 60min, 4°C). The supernatant was mixed 1:1 with deionized water after filtering with 0.45μm filters to remove cell sediment. Each sample was again filtered through a 0.22μm syringe filter before profile acquisition. The metabolic profile was acquired using liquid chromatography coupled with time-of-flight mass spectrometry. A total of 18 target metabolites were identified after analysis. The metabolites were tryptophan, lactic acid, ornithine, stearic acid, oleic acid, palmitic acid, melatonin, acetylcarnitine, carnitine,phenylalanine, isoleucine, isovaleryl, citric acid, hippuricacid, 1,3-dioxan-5-ol, taurine, phosphoric acid, and fructose. Groups were considered independent factors while the metabolite profile was considered a dependent factor. The Shapiro-Wilk Test was used to evaluate data distribution of SP metabolomics. The Kruskal Wallis test for nonparametric data and ANOVA and Tukey test for parametric data were used. Pearson's correlation was performed with a significance level of P<0.05. Four metabolites: oleic acid, isoleucine, taurine, and phosphoric acid, presented a difference (P<0.05) between the HP and LP groups. The oleic acid and isoleucine were higher in the LP group, while taurine and phosphoric acid were higher in stallions from the HP group. Phosphoric acid presented a relevant negative correlation with immobile spermatozoa (r=-0.7206) and a positive correlation with functional integrity (r=0.6162), physical integrity (r=0.6306), fertility (r=0.6471), progressive motility (r=0.5145), total motility (r=0.7157), VCL (r=0.6034), VSL (r=0.5491), VAP (r=0.5629), BCF (r=0.7055), ALH (r=0.5945), the total volume of the ejaculate (r=0.5941) and total protein/ejaculated (r=0.5182). Metabolites are products of cell signaling pathways and can be used as biological markers. Phosphoric acid contributes to the energy metabolism of sperm by breakdown of an inorganic pyrophosphate molecule. In conclusion, phosphoric acid in stallion SP should be considered as a marker of fertility.
The physiological behavior of PSII measured by chlorophyll
a
fluorescence explains stress responses; wonders if it can differentiate plants from different populations. For this purpose, acclimated ...young plants of two
C. pachystachya
populations were cultivated from seeds. Chlorophyll-
a
fluorescence was measured after fertilization and CO
2
e
. In the first 48 h after fertilization there was a reduction in the maximum quantum yield of PSII, while the means obtained under CO
2
e
were significantly higher than in other treatments (0.8 and 0.81). The variable PI best expressed the different conditions tested. Compared to their respective controls, the reduction of DIo/CS was 35.89 % in population (P) and 41.89 % in population (I), while the polyphasic fluorescence kinetics differed between treatments, but not necessarily between populations, except for post-fertilization at
I-P
steps. The analysis of kinetics between Fo and Fj (Wt) showed no
K
band during the
O
-
J
phase. The interferences found in PSII reinforces the idea of reversible damage to PSII. This effect is directly related to the reduced electron transport rate and increased non-photochemical dissipation and may be similar to those observed under field conditions after planting; adjustment time depends, among other factors, on the genetic potential of the species.
The physiological behavior of PSII measured by chlorophyll a fluorescence explains stress responses; wonders if it can differentiate plants from different populations. For this purpose, acclimated ...young plants of two C. pachystachya populations were cultivated from seeds. Chlorophyll-a fluorescence was measured after fertilization and CO sub(2) sub(e). In the first 48 h after fertilization there was a reduction in the maximum quantum yield of PSII, while the means obtained under CO sub(2) sub(e) were significantly higher than in other treatments (0.8 and 0.81). The variable PI best expressed the different conditions tested. Compared to their respective controls, the reduction of DIo/CS was 35.89 % in population (P) and 41.89 % in population (I), while the polyphasic fluorescence kinetics differed between treatments, but not necessarily between populations, except for post-fertilization at I-P steps. The analysis of kinetics between Fo and Fj (Wt) showed no K band during the O-J phase. The interferences found in PSII reinforces the idea of reversible damage to PSII. This effect is directly related to the reduced electron transport rate and increased non-photochemical dissipation and may be similar to those observed under field conditions after planting; adjustment time depends, among other factors, on the genetic potential of the species.
We use electron transport to characterize monolayer graphene - multilayer MoS2 heterostructures. Our samples show ambipolar characteristics and conductivity saturation on the electron branch which ...signals the onset of MoS2 conduction band population. Surprisingly, the carrier density in graphene decreases with gate bias once MoS2 is populated, demonstrating negative compressibility in MoS2. We are able to interpret our measurements quantitatively by accounting for disorder and using the random phase approximation (RPA) for the exchange and correlation energies of both Dirac and parabolic-band two-dimensional electron gases. This interpretation allows us to extract the energetic offset between the conduction band edge of MoS2 and the Dirac point of graphene.
