Subject:
All Disciplines Arts & Humanities Biology & Life Sciences Business & Economics Chemistry & Materials Science Computer Science & Mathematics Engineering Environmental & Earth Sciences Medicine & Pharmacology Physical Sciences Public Health & Healthcare Social Sciences
Sort:
Hottest Latest Alphabetical (A-Z) Alphabetical (Z-A)
Type:
All Topic Review Biography
Biography
Walter Heitler
Walter Heinrich Heitler (German: [ˈhaɪtlɐ]; 2 January 1904 – 15 November 1981) was a German physicist who made contributions to quantum electrodynamics and quantum field theory. He brought chemistry under quantum mechanics through his theory of valence bonding. In 1922, Heitler began his study of physics at the Karlsruhe Technische Hochschule, in 1923 at the Humboldt University of Berlin
  • 1.6K
  • 07 Dec 2022
Topic Review
Application of Microbes in Pesticide Degradation
Microbes (fungal and bacterial) applications have been identified for the bio-degradation of agro-chemicals within the environment. The efficiency of microbial species to bio-degrade chemicals varies considerably. Pesticide remediation using microbes transforms harmful chemicals into nontoxic, eco-friendly, and beneficial metabolites. During pesticides decomposition, the biosorption rate for a single strain is insufficient, whereas the focus of degradation studies is rapidly turning towards microbiological consortiums, and pesticide bio-degradability is determined through pesticide components, available mechanisms, and the promiscuity of enzymes. Certain pesticides break down relatively faster than others. The slower ones are trinitrotoluene (TNT), polychlorinated biphenyl (PCBs), and pentachlorophenol (PCP). However, methomyl, pyrethroids, 1,3-dichloropropene, and atrazine can degrade faster. Axenic cultured cells are concentrated more on pesticides breakdown than microbial consortia. Earlier research has examined various microbial communities that, particularly axenic strains, may degrade chemicals quickly. During investigations, both single and a mixture of microbial strains are effective. Although axenic cells seem critical in metabolic studies, their physiology and molecular compositions are related to pesticide decomposition. The synthesis of the consortium was achieved premised on the performances of axenic colonies in pesticide degrading, and the microbial consortia became identified to have the tremendous potential.
  • 1.6K
  • 24 May 2022
Topic Review
Grape Phenolics
Grapes are rich in primary and secondary metabolites. Among the secondary metabolites, polyphenolic compounds are the most abundant in grape berries. Besides their important impacts on grape and wine quality, this class of compounds has beneficial effects on human health. Due to their antioxidant activity, polyphenols and phenolic acids can act as anti-inflammatory and anticancerogenic agents, and can modulate the immune system. In grape berries, polyphenols and phenolic acids can be located in the pericarp and seeds, but distribution differs considerably among these tissues. Although some classes of polyphenols and phenolic acids are under strict genetic control, the final content is highly influenced by environmental factors, such as climate, soil, vineyard, and management. 
  • 1.6K
  • 13 Jan 2021
Topic Review
Taro Mucilage
Taro (Colocasia esculenta) is an important source of carbohydrates as an energy source and is used as a staple food throughout the world. It is rich in mucilage and starch granules, making it a highly digestible ingredient. Mucilage can act as a matrix and a thickening, binding, emulsifying, or foaming agent in food, pharmaceutical, and several other fields of research. Moreover, mucilage can be extracted from several living organisms and has excellent functional properties, such as water-holding, oil-holding, and swelling capacities. Therefore, these remarkable functional properties make mucilage a promising ingredient with possible industrial applications. Furthermore, several extraction techniques, including enzyme-assisted, ultrasonication, microwave-assisted, aquatic, and solvent extraction methods, are used to obtain quantitative amounts of taro mucilage. Coldwater extraction with ethanol precipitation can be considered an effective and cost-effective technique to obtain high-quality mucilage with suitable industrial applications, whereas the ultrasonication method is more expensive but results in a higher amount of mucilage than other emerging techniques. Mucilage can also be used as a fat replacer or reducer, dye remover, coating agent, and antioxidating agent
  • 1.6K
  • 25 Mar 2022
Topic Review
Castor Bean
Castor bean (Ricinus communis L.) is an unpalatable tropical plant belonging to the spurge family (Euphorbiaceae). It has great phytoremediation potential and is used for biofuels production. Its cultivation on contaminated and marginal land can be considered a great alternative to fossil fuel, lowering the social-economic implication and ecological impacts of biodieselproduction. In this entry, we analyze the botanical, agronomical, and the by-product obtainable from castor bean. More information about the castor bean phytoremediation potential and its resistance to abiotic stresses can be found at 10.3390/agronomy10111690  
  • 1.6K
  • 06 Nov 2020
Topic Review
Coumarin-Based Profluorescent and Fluorescent Substrates
Activities of xenobiotic-metabolizing enzymes have been measured with various in vitro and in vivo methods, such as spectrophotometric, fluorometric, mass spectrometric and radioactivity-based techniques. In fluorescence-based assays, the reaction produces a fluorescent product from a nonfluorescent substrate or vice versa. We describe here historical highlights and current use of (pro)fluorescent coumarin derivatives in evaluating activities of the major types of xenobiotic-metabolizing enzyme systems. Traditionally coumarin substrates have been used to measure oxidative activities of cytochrome P450 (CYP) enzymes. For this purpose, profluorescent coumarins are very sensitive, but generally lack selectivity for individual CYP forms. The entry describes several new coumarin-based substrates for measuring activities of CYP and conjugating enzymes with improved selectivity.
  • 1.6K
  • 14 Jul 2020
Topic Review
Human Cytomegalovirus
Human cytomegalovirus (HCMV) expresses a variety of viral regulatory proteins that undergo close interaction with host factors including viral-cellular multiprotein complexes. The HCMV protein kinase pUL97 represents a viral CDK ortholog (vCDK) that determines the efficiency of HCMV replication via phosphorylation of viral and cellular substrates. A hierarchy of functional importance of individual pUL97-mediated phosphorylation events has been discussed, however, the most pronounced pUL97-dependent phenotype could be assigned to viral nuclear egress, as illustrated by genetic ORF-UL97 deletion or pharmacological pUL97 inhibition. Despite earlier data pointing to a cyclin-independent functionality, experimental evidence increasingly emphasized the role of pUL97-cyclin complexes. Consequently, the knowledge about pUL97 involvement in host interaction, viral nuclear egress and additional replicative steps led to the postulation of pUL97 as an antiviral target. Indeed, validation experiments in vitro and in vivo confirmed the sustainability of this approach. Consequently, current investigations of pUL97 in antiviral treatment go beyond the known pUL97-mediated ganciclovir prodrug activation and henceforward include pUL97-specific kinase inhibitors. Among a number of interesting small molecules analyzed on experimental and preclinical stages, maribavir is presently investigated in clinical studies and, in the near future, might represent a first kinase inhibitor applied in the field of antiviral therapy.
  • 1.6K
  • 29 Oct 2020
Topic Review
Spring Wheat
Spring wheat as durum or bread wheat is grown worldwide in mega-environments (ME; 1-6) at latitudes <40 degree during the winter or early spring season and flower in short days with relatively little vernalization requirement. Based on protein contents, kernel color and hardness of endosperm, spring wheat is classified into hard red, soft white and hard white spring with high baking quality.  
  • 1.6K
  • 13 Sep 2021
Topic Review
Legume Use in Extrusion Cooking
The traditional perception that legumes would not be suitable for extrusion cooking is now completely outdated. In the recent years an increasing number of researches have been conducted to assess the behavior of various types of legume flours in extrusion cooking, proving that legumes have excellent potential for the production of extruded ready-to-eat foods by partially or totally replacing cereals. There are optimal processing conditions for legume-based and legume-added extruded foods, which allow to improve the expansion ratio and give the extrudates the spongy and crisp structure expected by consumers. The extrusion cooking process has also a positive effect on the nutritional characteristics of legumes, because induces important modifications on starch and proteins, enhancing their digestibility, and reduces the content of trypsin inhibitors, lectins, phytic acid, and tannins. Therefore, the extrusion of legume flours is a viable strategy to improve their nutritional features while reducing home preparation time, so as to increase the consumption of these sustainable crops.
  • 1.6K
  • 27 Oct 2020
Topic Review
Bisindole Alkaloids from Alstonia Species
Bisindoles are structurally complex dimers and are intriguing targets for partial and total synthesis. They exhibit stronger biological activity than their corresponding monomeric units. Bisindole alkaloids are naturally occurring alkaloids containing two indole nuclei and are the products of late-stage biosynthetic processes in higher plants by combining two monomeric units. Depending on the monomeric units involved, bisindoles can be a homo- or heterodimer. As a result, bisindole alkaloids comprise much higher structural complexity than both of the monomeric units that comprise them. Alstonia, a major genus in the Apocynaceae family of plants, has more than 150 species and is found all over the world. Robert Brown named it in 1811 in honor of Charles Alston (1685–1760), an eminent botanist at the University of Edinburgh. The Alstonia genus’ trees and shrubs are prevalent in the tropical and subtropical parts of Africa, Asia, and Australia. They contribute significant pharmacological activity, including anticancer, antileishmanial, antimalarial, antitussive, antiviral, antiarthritic, and antibacterial activities. 
  • 1.6K
  • 30 Jun 2021
  • Page
  • of
  • 1815
Featured Entry Collections
>>

Featured Books

>>
Encyclopedia of Social Sciences
Encyclopedia of COVID-19
Encyclopedia of Fungi
Encyclopedia of Digital Society, Industry 5.0 and Smart City
ScholarVision Creations
Feedback