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Cancer remains as one of the most common cause of mortality worldwide. Cancer chemoprevention by natural products is well accepted nowadays. Phytoserols are natural products, showing anticancer activity, besides other activities. The purpose of this study was to examine the antitumor and antioxidant activity of stigmasterol, a phytosterol isolated from aerial parts of Bacopa monnieri Linn. against Ehrlich Ascites Carcinoma (EAC) in swiss albino mice. The effect of stigmasterol on the growth of transplantable murine tumor, life span of EAC bearing hosts, simultaneous alterations in the hematological profile, liver biochemical parameters (lipid peroxidation, antioxidant enzymes) and histopthological studies of liver were examined. Stigmasterol decreased tumor volume, packed cell volume and viable cell count, and increased mean survival time thereby increasing life span of EAC tumor bearing mice. Hematological profile reverted to near normal levels in stigmasterol treated mice. Stigmasterol decreased the levels of lipid peroxidation and increased the levels of glutathione, superoxide dismutase and catalase in the liver of EAC bearing mice. Histopathological study of liver tissues showed that stigmasterol had significant protective effect against EAC bearing mice, which corroborates the above findings. Lactate dehydrogenase (LDH) activity in ascitic fluid increased while membrane microviscosity of the EAC cells decreased upon stigmasterol treatment indicating its effect in the membrane integrity functions. The antitumor activity of stigmasterol might be mediated through the activation of protein phosphatase 2A by ceramide causing apoptosis, as is shown by structurally similar phytosterol.

The synthetic application of nickel catalysts in Heck-coupling reactions is quite prominent and noticeable of late in organic synthesis. It shows great interest over the other transition metal catalysts due to its unique characteristic that prepares them more significantly applicable in different fields of synthetic application. The usefulness of nickel-catalysts relies in the fact that they are abundant in nature, relatively less precious and environment friendly. Nickel plays pivotal role in different kind of Heck reactions known such as intramolecular-, intermolecular-, reductive-Heck type reaction producing mainly carbocycles and hetero cycles of biological significance. Carbocyclization or hetero-cyclization reaction occurred under optimized reaction conditions developed and come up with the formation of various structural building blocks of naturally occurring compounds. Via reductive Heck cyclization large membered ring of carbo-or hetero-cyclic system was formed which performed key role as building blocks in pharmaceutical synthesis and bioactive molecule formation. Intermolecular Heck type reactions were comparatively more explored. Silyl-Heck, carbonyl-Heck, and other miscellaneous type reactions were covered up through nickel-catalyzed intermolecular Heck reaction. Asymmetric versions of Heck-coupling reactions are also reported to proceed even with unactivated alkenes, offering molecules having quaternary stereogenic center in a regio-and enantioselective manner. This manuscript intends to cover these entire concepts.

SUMMARY BackgroundGastric acid has an important pathophysiological role in human beings. Numerous methods have been evaluated over the years in an attempt to measure gastric acid and stomach acidity, to study the role of gastric acid in gastrointestinal diseases in humans and to evaluate the effects of acid suppressing drugs.

Conspectus In the last 50 years, an important aim of molecular and materials design has been the generation of space for the uptake of guest molecules in macrocycles and cryptands, in dendrimers as monomolecular containers, and recently in porous networks like metal–organic and covalent organic frameworks. Such molecular, oligomeric, and polymeric materials can be applied for sensing, separation, catalysis, drug delivery, and gas storage, among others. The common goal is the recognition of molecules and their uptake into and release from an appropriate space. Typically, completely empty space is unfavorable in crystalline materials. Therefore, the elimination of molecules from the cavities is often accompanied by the collapse of the cavities, that is, by a change in the molecular conformation. In contrast to this solid matter, in which the cavities are rationally designed by covalent or coordinative bonds, liquid crystals (LCs) are fluid materials with high molecular mobility. Thus, the proposal of empty space in LCs is certainly a scientific provocation. However, various recent publications on columnar mesophases claim the existence of pores with low electron density or even completely empty space on the basis of X-ray and solid-state NMR studies. Although the latter may be debated, there are many examples in which LCs take up dopants such as polymerizable monomers in disclination lines, perdeuterated chains in the interstices between columns, or electron acceptors to fill mesogens with incommensurate building blocks, which eventually stabilize the LC phases. It seems that in LC science the generation and usage of free space has been studied only occasionally and were lucky discoveries rather than investigations based on rational design. This Account summarizes the research on the formal generation of void in LCs and highlights that rational design of molecules can lead to unconventional mesophases by efficient filling of the provided space, as was shown with shuttlecock mesogens and discotic mesogens related to the concept of complementary polytopic interactions. The topic was recently further developed by the investigation of shape-persistent star mesogens. Despite the formally empty space between their arms, they all form columnar liquid crystals. Such shape-persistent oligo­(phenylenevinylene) molecules fill the void and efficiently nanosegregate by helical packing in columns and deformation of the molecular scaffold at the expense of the torsional energy. This inspired us to fill the intrinsic free space by guest molecules either via supramolecular or covalent bonds or just by physical mixing in order to avoid the increase in torsional energy and to stabilize the structure. This strategy led to complex filled liquid-crystalline matter with high structural control and may in the future be used for the design of organic electronic materials that are easily alignable for device applications.

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The optimised model depicted MeOH at 30 °C with an extended time of 150 min as the optimum settings for extraction of compounds from strawberry that had the scavenging activity. The study shows that the extraction of natural antioxidants from strawberry can be improved by optimising several key extraction parameters. SE also acted as an effective antioxidant and suppressed lipid peroxidation in cooked chicken patties.