Relationship of coal extraction with free radicals and coal macerals

1988 ◽  
Vol 18 (3) ◽  
pp. 279-286 ◽  
Author(s):  
Mohindar S. Seehra ◽  
Bikas Ghosh ◽  
John W. Zondlo ◽  
Eric A. Mintz
1998 ◽  
Vol 41 (18) ◽  
pp. 3477-3492 ◽  
Author(s):  
Murali C. Krishna ◽  
William DeGraff ◽  
Olga H. Hankovszky ◽  
Cecília P. Sár ◽  
Tamás Kálai ◽  
...  

2020 ◽  
Vol 11 (2) ◽  
pp. 96-100 ◽  
Author(s):  
Tulika Mishra ◽  
Ananda Kumar Kondepati ◽  
Shalini Devaprasad Pasumarthi ◽  
Gurmit Singh Chilana ◽  
Suresh Devabhaktuni ◽  
...  

Plants have always been an integrated part of human life, whether we discuss about providing food or we about their medicinal value. Ethnomedicines have led to the discovery of many valuable drugs against various diseases. It has been postulated that most of the disease are related to immune system which is affected by imbalance balance between antioxidants and prooxidants or free radicals. Free radicals are the chemical entities capable of independent existence that contain one/more unpaired electrons and can be balanced by antioxidants. Antioxidants maintain the integrity and function of membrane lipids, cellular proteins, and nucleic acids and the control of signal transduction of gene expression in immune cells. For this reason, the immune cells are particularly sensitive to changes in their antioxidant status. Whenever there is imbalance between prooxidant and antioxidants they can lead to many diseases and even ameliorate the severity of disease like Alzheimer, cardiovascular disorder, cancer etc. There are evidences showing usage of plants as a potent source of antioxidants has provided a lot of support in combating various diseases, without any side effect. Various Bioflavonoids, Carotenoids, Hydroxycinnamates etc helps in scavenging the free radicals and thus proved to be immunostimulant. There are various mechanisms through which these Phyto antioxidants assisted against various disease. The present review is an attempt showing the relationship of free radicals with various diseases and immune system and the role of Phyto antioxidants against various health related conditions.


2018 ◽  
Vol 13 (3) ◽  
pp. 1934578X1801300 ◽  
Author(s):  
Karolina A. Wojtunik-Kulesza ◽  
Łukasz M. Cieśla ◽  
Monika Waksmundzka-Hajnos

Data available in the literature indicated various biological activities of terpenes. One of the most frequently investigated activities is the ability to scavenge free radicals. To date, studies based on the DPPH• method indicated conjugated double bonds as moieties responsible for antioxidant activity of selected terpenes. In order to verify this theory, studies based on 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) were performed. The spectrophotometric investigations explicitly revealed relatively high antioxidant activity of terpenes possessing conjugated double bonds in comparison with substances without this structural element. It has been shown that the chain-breaking antioxidant activity of terpenes strictly depends on π bonds. TEAC values and percentage scavenging of the free radicals revealed that the most promising antioxidants are α-terpinene, ocimene, pulegone and farnesene. In order to explain the reaction between terpenes and ABTS•+ free radical cation, a possible antioxidant mechanism has been proposed.


Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
Author(s):  
William A. Oliver

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.


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