scholarly journals The Characterization of Active Compound of Pedada Magrove Plants (Sonneratia caseolaris) Which HaveThePotential as Natural Antioxidants

2019 ◽  
Vol 1 (1) ◽  
pp. 1-11
Author(s):  
Madyawati Latief
Keyword(s):  
Antioxidant Activity ◽  
Natural Antioxidants ◽  
Yellow Crystal ◽  
Two Dimensional ◽  
Spectroscopy Data ◽  
Separation And Purification ◽  
Sonneratia Caseolaris ◽  
A Value ◽  
Multi Stage

The present research aimedto isolate the compound from the acetone fractions of pedada leaves (Sonneratia caseolaris) and test its antioxidant activity. The extraction wasperformed usinga multi-stage maceration method. The separation and purification were done using a vacuum and gravitational column chromatography whereasthe antioxidant activity was tested with theDPPH method. The structural elucidation of the compound was performed by spectroscopy data of UV, IR, alsoone- and two-dimensional NMR. The appearance of the pure isolate was odorless yellow crystal. Based on the spectroscopy data, the compound wasstigmasta-5,22-dien-3-ol. The activity testing of the extract antioxidant and pure isolate with IC50showed a value of 166.2 ppm dan 134.4 ppm, respectively.

scholarly journals Antioxidant Activity and Characterization of One New Polysaccharide Obtained fromPerigord Truffle(Tuber huidongense)

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Yong-Feng Chen ◽  
Wen-wen Jiang ◽  
Shi-qi Zhang ◽  
Jian-quan Kan ◽  
Yong Liang
Keyword(s):  
Molecular Structure ◽  
Antioxidant Activity ◽  
Structural Characteristics ◽  
Water Soluble ◽  
Separation And Purification ◽  
Edible Fungus ◽  
Main Components ◽  
First Time

As a medicinal and edible fungus parasitizing on the trees, Perigord Truffle (Tuber huidongense) is well known for its delicious taste, unique smell, and high medical value for healthcare. One new water-soluble nonstarch polysaccharide (PST-W with the yield of 0.41%) fromPerigord Truffle(Tuber huidongense) was purified and identified on structural characteristics for the first time. The characterizations of PST-W were studied on physicochemical properties, main components of monosaccharide(s), and molecular structure. The monosaccharide compositions of PST-W were studied and identified as glucan, only containing D-glucoses with the molecular structure of [→6)α-D-Glcp(1→6)  α-D-Glcp (1→]nby methylation analysis and NMR. In the determination of total reducing capacity, the reducing abilities of polysaccharide extracts could be listed as vitamin C > PST-W > crude polysaccharides-3 > crude polysaccharides-2 > crude polysaccharides-1. All of PST-W, crude polysaccharides-2, and crude polysaccharides-3 were relatively good scavenger for 1,1-Diphenyl-2-picrylhydrazyl radical 2,2-Diphenyl-1-(2,4,6-trinitrophenyl)hydrazyl radicals with IC50of 2.81, 4.17, and 3.44 mg/mL, respectively. However,O2-∙clearing abilities of PST-W and crude polysaccharides were obviously weaker. The activities of total crude extract were the worst, indicating that the impurities might negatively affect the antioxidant activity. Thus, the separation and purification of polysaccharides were significant to increase the antioxidant activity in some degree.

Characterization of compounds in crude oils by gas purge micro-syringe extraction coupled to comprehensive two-dimensional gas chromatography

2014 ◽  
Vol 32 (10) ◽  
pp. 1144
Author(s):  
Ting TONG ◽  
Wanfeng ZHANG ◽  
Donghao LI ◽  
Jinhua ZHAO ◽  
Zhenyang CHANG ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Crude Oils ◽  
Two Dimensional ◽  
Gas Purge

SCALING ANALYSIS OF THE A-PHASE DYNAMICS DURING SLEEP

Fractals ◽  
2020 ◽  
Vol 28 (02) ◽  
pp. 2050050
Author(s):  
V. E. ARCE-GUEVARA ◽  
M. O. MENDEZ ◽  
J. S. MURGUÍA ◽  
A. ALBA ◽  
H. GONZÁLEZ-AGUILAR ◽  
...  
Keyword(s):  
Binary Sequence ◽  
Fluctuation Analysis ◽  
Scaling Analysis ◽  
Scaling Exponent ◽  
Sleep State ◽  
Phase Dynamics ◽  
A Value ◽  
Sleep Condition ◽  
Detrended Fluctuation

In this work, the scaling behavior of the sleep process is evaluated by using detrended fluctuation analysis based on wavelets. The analysis is carried out from arrivals of short and recurrent cortical events called A-phases, which in turn build up the Cyclic Alternating Pattern phenomenon, and are classified in three types: A1, A2 and A3. In this study, 61 sleep recordings corresponding to healthy, nocturnal frontal lobe epilepsy patients and sleep-state misperception subjects, were analyzed. From the A-phase annotations, the onsets were extracted and a binary sequence with one second resolution was generated. An item in the sequence has a value of one if an A-phase onset occurs in the corresponding window, and a value of zero otherwise. In addition, we consider other different temporal resolutions from 2[Formula: see text]s to 256[Formula: see text]s. Furthermore, the same analysis was carried out for sequences obtained from the different types of A-phases and their combinations. The results of the numerical analysis showed a relationship between the time resolutions and the scaling exponents; specifically, for higher time resolutions a white noise behavior is observed, whereas for lower time resolutions a behavior towards to [Formula: see text]-noise is exhibited. Statistical differences among groups were observed by applying various wavelet functions from the Daubechies family and choosing the appropriate sequence of A-phase onsets. This scaling analysis allows the characterization of the free-scale dynamic of the sleep process that is specific for each sleep condition. The scaling exponent could be useful as a diagnosis parameter in clinics when sleep macrostructure does not offer enough information.

scholarly journals Characterization of Chromium Compensated GaAs Sensors with the Charge-Integrating JUNGFRAU Readout Chip by Means of a Highly Collimated Pencil Beam

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1550
Author(s):  
Dominic Greiffenberg ◽  
Marie Andrä ◽  
Rebecca Barten ◽  
Anna Bergamaschi ◽  
Martin Brückner ◽  
...  
Keyword(s):  
Low Noise ◽  
State University ◽  
Noise Performance ◽  
X Ray ◽  
A Value ◽  
Resolution Capability ◽  
Sensor Properties ◽  
Pixel Pitch ◽  
Lower Noise

Chromium compensated GaAs or GaAs:Cr sensors provided by the Tomsk State University (Russia) were characterized using the low noise, charge integrating readout chip JUNGFRAU with a pixel pitch of 75 × 75 µm2 regarding its application as an X-ray detector at synchrotrons sources or FELs. Sensor properties such as dark current, resistivity, noise performance, spectral resolution capability and charge transport properties were measured and compared with results from a previous batch of GaAs:Cr sensors which were produced from wafers obtained from a different supplier. The properties of the sample from the later batch of sensors from 2017 show a resistivity of 1.69 × 109 Ω/cm, which is 47% higher compared to the previous batch from 2016. Moreover, its noise performance is 14% lower with a value of (101.65 ± 0.04) e− ENC and the resolution of a monochromatic 60 keV photo peak is significantly improved by 38% to a FWHM of 4.3%. Likely, this is due to improvements in charge collection, lower noise, and more homogeneous effective pixel size. In a previous work, a hole lifetime of 1.4 ns for GaAs:Cr sensors was determined for the sensors of the 2016 sensor batch, explaining the so-called “crater effect” which describes the occurrence of negative signals in the pixels around a pixel with a photon hit due to the missing hole contribution to the overall signal causing an incomplete signal induction. In this publication, the “crater effect” is further elaborated by measuring GaAs:Cr sensors using the sensors from 2017. The hole lifetime of these sensors was 2.5 ns. A focused photon beam was used to illuminate well defined positions along the pixels in order to corroborate the findings from the previous work and to further characterize the consequences of the “crater effect” on the detector operation.

scholarly journals Phenolic Composition and Antioxidant Activity of Plants Belonging to the Cephalaria (Caprifoliaceae) Genus

Plants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 952
Author(s):  
Małgorzata Chrząszcz ◽  
Barbara Krzemińska ◽  
Rafał Celiński ◽  
Katarzyna Szewczyk
Keyword(s):  
Antioxidant Activity ◽  
Lung Diseases ◽  
Antioxidative Activity ◽  
Biological Activities ◽  
Natural Antioxidants ◽  
Antioxidant Effect ◽  
In Vivo Studies ◽  
Phenolic Composition

The genus Cephalaria, belonging to the Caprifoliaceae family, is a rich source of interesting secondary metabolites, including mainly saponins which display a variety of biological activities, such as immunomodulatory, antimicrobial and hemolytic effects. Besides these compounds, flavonoids and phenolic acids were identified in Cephalaria species. Cephalaria is employed in traditional medicine e.g., to cure cardiac and lung diseases, rheumatism, and regulate menstruation. In this review we focus on the phenolic compound composition and antioxidative activity of Cephalaria species. The antioxidant effect can be explained by flavonoids present in all parts of these plants. However, future efforts should concentrate more on in vitro and in vivo studies and also on clinical trials in order to confirm the possibility of using these plants as natural antioxidants for the pharmacology, food or cosmetic industries.

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