PHARMACOGNOSTICAL AND PHYTOCHEMICAL STUDY ON LEAF OF COMBRETUM INDICUM (L.)

Combretum indicum (L.) is an extra-pharmacopeial drug with an abundance of medicinal properties. Throughout the world, different Parts of Combretum indicum (L.) is used in curing many ailments by folklore healers. In India, the drug Combretum indicum (L.) is commonly known by the name MadhuMalathi and used by the folklore healers of different areas. Especially the use of Combretum indicum (L.) is seen among the folklore Practitioners of Dakshina Kannada District in curing ailments including paediatric conditions. Thus, it is very important to explore the identity of this drug by the proper Pharmacognostical and Phytochemical analysis. Hence, the present study was aimed at Pharmacognostical and Phytochemical study on Leaf of Combretum indicum (L.). The transverse section of the midrib of the leaf shows the presence of the endodermal layer; which is single-layered, surrounds by a vascular bundle and packed with starch grains. Endodermis covers the vascular bundle and contains several starch grains. The powder microscopy shows the presence of glandular trichome, calcium oxalate crystals etc. The percentage of extractive value was maximum in methanol which was 7.18%, Preliminary phytochemical study showed the presence of Proteins, Carbohydrates, Tannins, Steroids, Alkaloids, Triterpenoids, Starch, Resin and Phenols. The total ash attained was 7.84% and the water-soluble ash was 3.4%.

Expression of Enzymes Associated with Prostaglandin Synthesis in Equine Conceptuses

In the horse, mobility of the conceptus is required for maternal recognition of pregnancy depending on secretion of prostaglandins by the conceptus. The aim of this study was to determine the expression and localization of key enzymes of the different pathways leading to synthesis of prostaglandin E2 and F2α in the equine conceptus during the mobility phase. Enzyme expression was analyzed via quantitative RT-PCR in total RNA samples of equine conceptuses collected on days 10 (n = 5), 12 (n = 12), 14 (n = 5) and 16 (n = 7) from healthy mares. Relative abundance of cyclooxygenase (COX)-2 mRNA was higher (p < 0.05) than of COX-1 irrespective of conceptus age and for phospholipase A2 on day 16 in comparison to all other days (p < 0.01). Abundance of mRNA of cytosolic and microsomal prostaglandin E synthase (PGES) and of carbonyl reductase (CBR) 1 was not influenced by conceptus age. Immunohistochemically, COX-1, COX-2, as well as cytosolic and microsomal PGES were present in both the ectodermal and endodermal layer of the yolk sac wall. CBR-1 was restricted to periembryonic disc area. The localisation of the key enzymes explains the mechanism of embryo mobility. In vitro incubation of primary trophoblast cell cultures with oxytocin had no effect on key enzyme synthesis.

Effects of cadmium on the anatomical structures of vegetative organs of chickpea (Cicer arientinum L.)

The effects of cadmium on the anatomical structures of different vegetative parts, namely root, stem and leaf of chickpea, Cicer arientinum L. was studied. Four different concentrations of CdCl2 e.g. 250, 500, 750 and 1000 μM were considered as treatments alongside non treated samples (control). In case of root anatomy decrease of root diameter, root cortex area, thick walled endodermal layer and reduced number of metaxylem vessels were observed compared to control. Similarly, stem diameter, cortical area, size and number of xylem vessels were decreased in Cd treated stem. However, large and increased number of trichomes had been found in Cd treated stem samples with deposition of phenolic compounds in vessels with increasing concentration of Cd. Considerable less toxic effects were observed in leaf anatomy except decrease in leaf thickness, reduced vascular area and closure of stomata in comparison to control sample. All such plant anatomical alterations indicated adverse effects as well as tolerance of chickpea up to certain concentrations of heavy metal to cope up with the changing environment. Dhaka Univ. J. Biol. Sci. 29(1): 45-52, 2020 (January)

Redundant SCARECROW genes pattern distinct cell layers in roots and leaves of maize

ABSTRACTThe highly efficient C4 photosynthetic pathway is facilitated by ‘Kranz’ leaf anatomy. In Kranz leaves, closely spaced veins are encircled by concentric layers of photosynthetic bundle sheath (inner) and mesophyll (outer) cells. Here we demonstrate that in the C4 monocot maize, Kranz patterning is regulated by redundant function of SCARECROW 1 (ZmSCR1) and a previously uncharacterized homeolog ZmSCR1h. ZmSCR1 and ZmSCR1h transcripts accumulate in ground meristem cells of developing leaf primordia and in Zmscr1;Zmscr1h mutant leaves, most veins are separated by one rather than two mesophyll cells; many veins have sclerenchyma above and/or below instead of mesophyll cells; and supernumerary bundle sheath cells develop. The mutant defects are unified by compromised mesophyll cell development. In addition to Kranz defects, Zmscr1;Zmscr1h mutants fail to form an organized endodermal layer in the root. Collectively, these data indicate that ZmSCR1 and ZmSCR1h redundantly regulate cell-type patterning in both leaves and roots of maize. Leaf and root pathways are distinguished, however, by the cell layer in which they operate – mesophyll at a two-cell distance from leaf veins versus endodermis immediately adjacent to root vasculature.Summary statementTwo duplicated maize SCARECROW genes control the development of the endodermis in roots and the mesophyll in leaves

Pharmacognostic and Phytochemical Evaluation of Trichosanthes dioica (R.)

Trichosanthes dioica seeds are mentioned in various traditional texts as a drug used for vermicidal anthelmintic, insecticidal, sedative, diuretic, demulcent, and expectorant purpose ethnopharmacologically. The studies were taken up to evaluate pharmacognostic, physicochemical and phytochemical standard for Trichosanthes dioica seeds. The objective of present study is to evaluate the morphological, microscopical, phytochemical and physicochemical properties of various bioactive compounds present in Trichosanthes dioica seeds. Preliminary phytochemical screening was done and HPTLC studies were carried out. CAMAG HPTLC system equipped with Linomat V applicator, TLC scanner, and WIN CATS-4 software were used. The microscopical studies of T. dioica seeds have showed mucilaginous epidermis made up of long thin trichomes, Innermost layer of parenchyma cells and sclerotic endodermal layer. Testa is 17-23 cells thick on the sides on the seeds. Exotesta: a layer shortly columnar pulpy cells, much elongate on the sides of micropyle thin walled but with fine fibrillar thickenings (not lignified) on the radial and inner wall, the outer wall thickened and slightly lignified, first filled with starch grains. Physico-chemical studies of T. dioica seeds have set the some standard i.e. Ether soluble extractive value 16.15%w/w, alcohol soluble extractive value 10.11% w/w, water soluble extractive value 9.22% w/w, Total Ash value 6.21 w/w, acid insoluble ash value 1.32% w/w, water soluble ash value 4.29% and loss on drying 24.33% w/w etc. were found out. Preliminary phytochemical screening was done then TLC and HPTLC studies were carried out. All the findings will be useful towards establishing pharmacognostic standards on identification, purity, quality and classification of the plant, which is gaining relevance in plant drug research for the identification and preparation of monograph of plant.

Gutsy moves in mice: cellular and molecular dynamics of endoderm morphogenesis

Despite the importance of the gut and its accessory organs, our understanding of early endoderm development is still incomplete. Traditionally, endoderm has been difficult to study because of its small size and relative fragility. However, recent advances in live cell imaging technologies have dramatically expanded our understanding of this tissue, adding a new appreciation for the complex molecular and morphogenetic processes that mediate gut formation. Several spatially and molecularly distinct subpopulations have been shown to exist within the endoderm before the onset of gastrulation. Here, we review findings that have uncovered complex cell movements within the endodermal layer, before and during gastrulation, leading to the conclusion that cells from primitive endoderm contribute descendants directly to gut.