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101.
RP-LC for Determination of Plastochromanol, Tocotrienols and Tocopherols in Plant Oils 总被引:1,自引:0,他引:1
An isocratic high performance liquid chromatographic method, with the application of C18 and C30 reverse-phase column and fluorescence detection, is described for the analysis of plastochromanol, tocotrienols and tocopherols in plant seed oils. The solvent systems have been optimized to obtain high resolution for all tocochromanols and relatively short analysis time. The use of reverse-phase columns for plastochromanol analysis, previously not reported, enables very sensitive and selective detection of plastochromanol which under the described separation conditions did not interfere with tocochromanols or any other compounds. The sample extraction method is fast, simple and highly efficient. The obtained results show that plastochromanol was present in most of the investigated seed oils. Its level was the highest in flax (17–30 mg/100 g oil), rape (8.5–9), camelina (4.3), peanut (1.95), corn (1.69) and grape (1.31) seed oils. Its level in the other investigated oils was below 1 mg/100 g oil, and only in sesame and coconut oils it was not detected. Tocotrienols were found in most of the oils but their content was usually very low (<<1 mg/100 g oil) with the exception of grape, milk thistle and corn oils where it reached >1 mg/100 g oil. Tocopherol content and isomer composition was within the earlier reported literature values for the investigated oils. 相似文献
102.
JPC – Journal of Planar Chromatography – Modern TLC - Carbohydrates have been examined by TLC on layers modified with metal ions, in the form of salts, by dipping commercial plates in... 相似文献
103.
Due to its carcinogenic properties, the presence of formaldehyde in resins and other industrial products has been a subject of great concern in recent years. The presented review focuses on modern alternatives for the production of wood-based panels; i.e., substitutes for formaldehyde in the production of amino and phenolic resins, as well as novel hardeners for formaldehyde-free wood adhesives. Solutions in which formaldehyde in completely replaced are presented in this review. Recent advances indicate that it is possible to develop new formaldehyde-free systems of resins with compatible hardeners. The formaldehyde substitutes that have primarily been tested are glyoxal, glutaraldehyde, furfural, 5-hydroxymethylfurfural, and dimethoxyethanal. The use of such substitutes eliminates the problem of free formaldehyde emission originating from the resin used in the production of wood-based panels. However, these alternatives are mostly characterized by worse reactivity, and, as a result, the use of formaldehyde-free resins may affect the mechanical and strength properties of wood-based panels. Nonetheless, there are still many substantial challenges for the complete replacement of formaldehyde and further research is needed, especially in the field of transferring the technology to industrial practice. 相似文献
104.
Jolanta Wawrzyniak Magdalena Rudziska Marzena Gawrysiak-Witulska Krzysztof Przyby 《Molecules (Basel, Switzerland)》2022,27(8)
The need to maintain the highest possible levels of bioactive components contained in raw materials requires the elaboration of tools supporting their processing operations, starting from the first stages of the food production chain. In this study, artificial neural networks (ANNs) and response surface regression (RSR) were used to develop models of phytosterol degradation in bulks of rapeseed stored under various temperatures and water activity conditions (T = 12–30 °C and aw = 0.75–0.90). Among ANNs, networks based on a multilayer perceptron (MLP) and a radial basis function (RBF) were tested. The model input constituted aw, temperature and storage time, whilst the model output was the phytosterol level in seeds. The ANN-based modeling turned out to be more effective in estimating phytosterol levels than the RSR, while MLP-ANNs proved to be more satisfactory than RBF-ANNs. The approximation quality of the ANNs models depended on the number of neurons and the type of activation functions in the hidden layer. The best model was provided by the MLP-ANN containing nine neurons in the hidden layer equipped with the logistic activation function. The model performance evaluation showed its high prediction accuracy and generalization capability (R2 = 0.978; RMSE = 0.140). Its accuracy was also confirmed by the elliptical joint confidence region (EJCR) test. The results show the high usefulness of ANNs in predictive modeling of phytosterol degradation in rapeseeds. The elaborated MLP-ANN model may be used as a support tool in modern postharvest management systems. 相似文献
105.
Zofia apiska Urszula Szwedowicz Anna Choromaska Jolanta Saczko 《Molecules (Basel, Switzerland)》2022,27(8)
Gynecological carcinomas affect an increasing number of women and are associated with poor prognosis. The gold standard treatment plan is mainly based on surgical resection and subsequent chemotherapy with cisplatin, 5-fluorouracil, anthracyclines, or taxanes. Unfortunately, this treatment is becoming less effective and is associated with many side effects that negatively affect patients’ physical and mental well-being. Electroporation based on tumor exposure to electric pulses enables reduction in cytotoxic drugs dose while increasing their effectiveness. EP-based treatment methods have received more and more interest in recent years and are the subject of a large number of scientific studies. Some of them show promising therapeutic potential without using any cytotoxic drugs or molecules already present in the human body (e.g., calcium electroporation). This literature review aims to present the fundamental mechanisms responsible for the course of EP-based therapies and the current state of knowledge in the field of their application in the treatment of gynecological neoplasms. 相似文献
106.
Oligonucleotide tools, as modulators of alternative splicing, have been extensively studied, giving a rise to new therapeutic approaches. In this article, we report detailed research on the optimization of bifunctional antisense oligonucleotides (BASOs), which are targeted towards interactions with hnRNP A1 protein. We performed a binding screening assay, Kd determination, and UV melting experiments to select sequences that can be used as a high potency binding platform for hnRNP A1. Newly designed BASOs were applied to regulate the mutually exclusive alternative splicing of the PKM gene. Our studies demonstrate that at least three repetitions of regulatory sequence are necessary to increase expression of the PKM1 isoform. On the other hand, PKM2 expression can be inhibited by a lower number of regulatory sequences. Importantly, a novel branched type of BASOs was developed, which significantly increased the efficiency of splicing modulation. Herein, we provide new insights into BASOs design and show, for the first time, the possibility to regulate mutually exclusive alternative splicing via BASOs. 相似文献
107.
Karol Jdrejko Katarzyna Kaa Katarzyna Sukowska-Ziaja Jolanta Pytko-Poloczyk Boena Muszyska 《Molecules (Basel, Switzerland)》2022,27(23)
Cordyceps spp. (belonging to the Ascomycota group) are entomopathogenic mushrooms that have traditionally been used in ethnomedicine in Asian countries such as China, Japan, Korea, and India. They are unique parasites of larvae of selected species of moths. Cordyceps militaris is one of the best sources of cordycepin. Worldwide, osteoporosis is one of the most common bone diseases, whose pharmacotherapy includes various medical interventions; however, the research and development of new molecules and new drugs is required. The impact of adenosine receptors (ARs) on the purinergic signaling pathway may regulate proliferation, differentiate dental pulp stem cells and bone marrow, and modulate osteogenesis and bone repair. The aim of the review was to collect and analyze the available data on the effects of Cordyceps spp. or cordycepin on bone function and related processes. To the best of our knowledge, this is the first systematic review in this perspective, not necessarily using mushroom raw material or even the isolated parent compound cordycepin, but new molecules that are analogs of nucleosides, such as those from C. militaris. This review found that Cordyceps spp. or isolated cordycepin interacts via the AR, 5′ adenosine monophosphate-activated protein kinase (AMPK), and adenosine-5′-triphosphate (ATP) signaling pathway and evaluated their impact on bones, teeth, and dental pulp. Cordyceps spp. was found to have the potential to develop regenerative medicines, thus providing an opportunity to expand the treatment or intervention methods in the recovery after traumatic injuries, convalescence, and terminal-stage or devastating diseases. 相似文献
108.
Wojciech Ziemichod Jolanta Kotlinska Ewa Gibula-Tarlowska Natalia Karkoszka Ewa Kedzierska 《Molecules (Basel, Switzerland)》2022,27(13)
Opioids are used to treat pain, but despite their effectiveness, they possess several side effects such as respiratory depression, tolerance and physical dependence. Cebranopadol has been evaluated as a solution to this problem. The compound acts on the mu opioid receptor and the nociceptin/orphanin receptor and these receptors co-activation can reduce opioid side-effects without compromising analgesia. In the present review, we have compiled information on the effects of cebranopadol, its pharmacokinetics, and clinical trials involving cebranopadol, to further explore its promise in pain management. 相似文献
109.
Jolanta Flieger Agata Siwek Magdalena Pizoń Anna Czajkowska‐Żelazko 《Journal of separation science》2013,36(9-10):1530-1536
This paper is devoted to application of ionic liquids as surfactants in LC of organic compounds, derivatives of 1,4‐thiosemicarbazides. According to HPLC requirements the most advantageous conditions such as transparency for ultraviolet light, low CMC, additional inorganic salt additives, and appropriate organic solvent were established. The CMC was determined using conductivity measurements. Suitability of two different stationary phases: RP‐C18 and cyanopropyl bonded phase was examined under micellar conditions. Chosen ionic liquid surfactant was compared to common traditional amphiphilic reagent – SDS. Elaborated on chromatographic micellar conditions were tested as a pilot technique for prediction of distribution coefficients of organic analytes in ionic liquid‐based aqueous two‐phase system. 相似文献
110.
In this paper, the derivation of macroscopic transport equations for this cases of simultaneous heat and water, chemical and water or electrical and water fluxes in porous media is presented. Based on themicro-macro passage using the method of homogenization of periodic structures, it is shown that the resulting macroscopic equations reveal zero-valued cross-coupling effects for the case of heat and water transport as well as chemical and water transport. In the case of electrical and water transport, a nonsymmetrical coupling was found.Notations
b
mobility
-
c
concentration of a chemical
-
D
rate of deformation tensor
-
D
molecular diffusion coefficient
-
D
ij
eff
macroscopic (or effective) diffusion tensor
-
electric field
-
E
0
initial electric field
-
k
ij
molecular tensor
-
j, j
*,
current densities
-
K
ij
macroscopic permeability tensor
-
l
characteristic length of the ERV or the periodic cell
-
L
characteristic macroscopic length
-
L
ijkl
coupled flows coefficients
-
n
i
unit outward vector normal to
-
p
pressure
-
q
t
,q
t
+
,
heat fluxes
-
q
c
,q
c
+
,
chemical fluxes
-
s
specific entropy or the entropy density
-
S
entropy per unit volume
-
t
time variable
-
t
ij
local tensor
-
T
absolute temperature
-
v
i
velocity
-
V
0
initial electric potential
-
V
electric potential
-
x
macroscopic (or slow) space variable
-
y
microscopic (or fast) space variable
-
i
local vectorial field
-
i
local vectorial field
-
electric charge density on the solid surface
-
,
bulk and shear viscosities of the fluid
-
ij
local tensor
-
ij
local tensor
-
i
local vector
-
ij
molecular conductivity tensor
-
ij
eff
effective conductivity tensor
-
homogenization parameter
-
fluid density
-
0
ion-conductivity of fluid
-
ij
dielectric tensor
-
i
1
,
i
2
,
i
3
local vectors
- 4
local scalar
-
S
solid volume in the periodic cell
-
L
volume of pores in the periodic cell
-
boundary between
S
and
L
-
s
rate of entropy production per unit volume
-
total volume of the periodic cell
-
l
volume of pores in the cell
On leave from the Politechnika Gdanska; ul. Majakowskiego 11/12, 80-952, Gdask, Poland. 相似文献