Improved methods to characterize the length and quantity of highly unstable PolySialic acids subject category: (Carbohydrates, chromatographic techniques)

2021 ◽  
pp. 114426
Author(s):  
Michael Vaill ◽  
Dillon Y. Chen ◽  
Sandra Diaz ◽  
Ajit Varki
2008 ◽  
Vol 128 (8) ◽  
pp. 1358-1366 ◽  
Author(s):  
Masao Yamamoto ◽  
Hisao Mase ◽  
Hiroshi Yajima ◽  
Hiroshi Kinukawa

1983 ◽  
Author(s):  
A. GLASSFORD ◽  
R. OSIECKI ◽  
C.-K. LIU ◽  
M. HITCHCOCK
Keyword(s):  

Author(s):  
Akanksha Gupta ◽  
Abhishek K Tripathi ◽  
Pushpraj S Gupta

Background: Bauhinia variegata Linn. is a native plant of Asia and China. B. variegata is found in tropical regions of the world. It belongs to family Leguminosae. It is used for diarrhea, hemorrhoids, constipation, piles, edema, leprosy, wounds, tumors, etc.  Objective: The objective of the present study was to perform extraction of B. variegata flower and isolation of active constituents from the extract. Materials and Methods: The ethanolic extraction of B. variegata flower was performed using the Soxhlet apparatus. The isolation of active constituents from the extract was performed using chromatographic techniques. In column chromatographic studies, n-hexane- [dichloromethane (DCM)] (2:8) was used as an eluting system and further purified through thin layer chromatography (TLC). Compound A and B were isolated through chromatographic techniques, then the molecular formula and characterization of these compounds were carried out with mass and infrared (IR) spectral analysis. Results and Discussion: The percentage yield of B. variegata ethanolic extract (BVE) was found to be 20.8% w/w. The different fractions were F1 having 12.5 grams with n-hexane, F2 (17.1 grams) with CH2Cl2, F3 (21.2 grams) with EtOAc, and F4 (13.4 grams) with EtOH. Compound A and B were isolated from the solvent fractions of n-hexane-DCM (2:8) and EtOAc-DCM (1:9), respectively. The compound A was characterized as 3-hydroxy-6-methoxy-2-phenyl-4H-chromen-4-one. The compound B was characterized as 3-hydroxy-6-methyl-2-phenyl-4H-chromen-4-one. Conclusion: Thus, B. variegata flowers possess active components that need to identify their biological activities.


2018 ◽  
Author(s):  
Andrew S. Fox ◽  
Regina Lapate ◽  
Alexander J. Shackman ◽  
Richard J Davidson

Emotion is a core feature of the human condition, with profound consequences for health, wealth, and wellbeing. Over the past quarter-century, improved methods for manipulating and measuring different features of emotion have yielded steady advances in our scientific understanding emotional states, traits, and disorders. Yet, it is clear that most of the work remains undone. Here, we highlight key challenges facing the field of affective sciences. Addressing these challenges will provide critical opportunities not just for understanding the mind, but also for increasing the impact of the affective sciences on public health and well-being.


Author(s):  
Z. Bolatbekova ◽  
S. Assylbekova ◽  
B. Kulatayev ◽  
S. Koishybayeva ◽  
N. Bulavina

The aryicle presents the results of a comparative study of the biochemical composition of earthworms of dendrobene and prospector rocks, the peculiarities of their cultivation and their use for feeding when growing juvenile tilapia and clary catfish. The experience of cultivating earthworms of two breeds using the improved methods of foreign authors is described. The results of a study of the biochemical composition of cultivated objects that determine their nutritional value for feeding fish are presented. The fish-breeding and biological indicators of juvenile tilapia and clary catfish, obtained during the cultivation of dendrobene and prospector in fish farming in the Almaty region (VI fish-breeding zone) during worm feeding, are analyzed. A comprehensive analysis of the studied indicators made it possible to assign a certain rating place to each worm breed in relation to its use as fish feed.


Author(s):  
Warren Brown

This paper details further progress made in the PVRC project “Development of Improved Flange Design Method for the ASME VIII, Div.2 Rewrite Project” presented during the panel session on flange design at the 2006 PVP conference in Vancouver. The major areas of flange design improvement indicated by that project are examined and the suggested solutions for implementing the improved methods into the Code are discussed. Further analysis on aspects such as gasket creep and the use of leakage-based design has been conducted. Shortcomings in the proposed ASME flange design method (ASME BFJ) and current CEN flange design methods (EN-1591) are highlighted and methods for resolution of these issues are suggested.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1397
Author(s):  
William N. Setzer ◽  
Lam Duong ◽  
Trang Pham ◽  
Ambika Poudel ◽  
Cuong Nguyen ◽  
...  

Virginia mountain mint (Pycnanthemum virginianum) is a peppermint-flavored aromatic herb of the Lamiaceae and is mainly used for culinary, medicinal, aromatic, and ornamental purposes. North Alabama’s climate is conducive to growing mint for essential oils used in culinary, confectionery, and medicinal purposes. There is, however, a need for varieties of P. virginianum that can be adapted and easily grown for production in North Alabama. Towards this end, four field-grown varieties with three harvesting times (M1H1, M1H2, M1H3; M2H1, M2H2, M2H3; M3H1, M3H2, M3H3, M4H1, M4H2, M4H3) were evaluated for relative differences in essential oil yield and composition. Thirty-day-old greenhouse-grown plants of the four varieties were transplanted on raised beds in the field at the Alabama A & M University Research Station in North Alabama. The plots were arranged in a randomized complete block with three replications. The study’s objective was to compare the four varieties for essential oil yield and their composition at three harvest times, 135, 155, and 170 days after planting (DAP). Essential oils were obtained by hydrodistillation with continuous extraction with dichloromethane using a Likens–Nickerson apparatus and analyzed by gas chromatographic techniques. At the first harvest, the essential oil yield of the four varieties showed that M1H1 had a yield of 1.15%, higher than M2H1, M3H1, and M4H1 with 0.91, 0.76, and 1.03%, respectively. The isomenthone concentrations increased dramatically through the season in M1 (M1H1, M1H2, M1H3) by 19.93, 54.7, and 69.31%, and M3 (M3H1, M3H2, M3H3) by 1.81, 48.02, and 65.83%, respectively. However, it increased only slightly in M2 and M4. The thymol concentration decreased slightly but not significantly in all four varieties; the thymol in M2 and M4 was very high compared with M1 and M3. The study showed that mountain mint offers potential for production in North Alabama. Two varieties, M1 and M3, merit further studies to determine yield stability, essential oil yield, composition, and cultivation development practices.


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