Prismatic Calcium Oxalate Crystals Research Articles

Pharmacognostical and Phytochemical Evaluation of Leaves of Bauhinia variegata Linn.

Bauhinia variegata Linn. (Caesalpiniaceae) syn: kovidara and kachnar is a medium sized deciduous tree generally found in sub Himalayan region of India. Almost all parts of this plant are used in traditional medicine for the treatment of various ailments. The present work was undertaken to establish the pharmacognostic and phytochemical standards along with HPTLC densitometric analysis of leaves for evaluating the plant material. The macro and microscopical studies indicated presence of pulvinus base with grooved petiolate leaf, emarginated apex, rough surface with 11–13 reticulate and palmate-divergent venation with scattered prismatic calcium oxalate crystals throughout the transverse section. Physiochemical studies revealed that total ash is 9.42%, acid insoluble ash is 5.72%, water-soluble extractive value is 3.30% and loss on drying at 105 °C is 6.27%. Preliminary phytochemical analysis revealed the presence of alkaloid, tannin, flavonoid, steroid, triterpenoid and saponin in different extracts. HPTLC fingerprinting for flavonoids revealed presence of two flavonoids rutin and kaempferol. The results of the study could be useful in setting some diagnostic indices for the identification and preparation of a monograph of the plant.

Morpho-anatomical study of the leaf and stem of pau-alecrim: Holocalyx balansae

Holocalyx balansae Micheli belongs to the Fabaceae family and is called pau-alecrim in Portuguese. In folk medicine, it is indicated to treat heart, hepatic and digestive upsets, as well as being considered anti-septic and diaphoretic. This work aimed to study the morpho-anatomy of the leaf and stem of this native medicinal species, in order to increase knowledge of the Brazilian flora and to contribute to pharmacognostic quality control. Samples of mature leaves and young stems were fixed and either sectioned free-hand or embedded in glycol-methacrylate and sectioned by microtome, then stained. Microchemical tests and scanning electron microscopy were also performed. The leaves are alternate, compound and paripinnate, and the leaflets have a lanceolate shape. Anomocytic and anisocytic stomata are found exclusively on the abaxial surface. The mesophyll is dorsiventral and the midrib, in cross-section, is flat on both sides, showing one collateral vascular bundle, encircled by a sclerenchymatic and crystalliferous sheath. The rachis and petiole present a collateral vascular bundle with a centric arrangement. The stem presents phellogen localized superficially. In the vascular cylinder, there is a sclerenchymatic sheath and continuous phloem and xylem cylinders, both traversed by narrow rays. Prismatic crystals of calcium oxalate are present in the leaf and stem.

Pharmacognostic and hypotensive evaluations of the stem bark of <i>Ficus exasperata</i> Vahl (Moraceae)

Elevated blood pressure is one of the non-communicable ailments whose control is attempted by the use of medicinal plants in ethnomedicine. In furtherance of our previous work on Ficus exasperata as a plant used in controlling elevated blood pressure, evaluations of the microscopy and other pharmacognostic parameters that could aid in the identification of the plant stem bark were carried out using standard methods. The probable effect of the methanol extract of the stem bark on anaesthetized normotensive rabbit blood pressure was also examined at doses of 5,10,20,30 and 40 mg/kg. The stem bark was observed to occur as flat and channelled pieces when fresh and single quill after drying. The powdered compound contained cork cells, cortical parenchyma, sclereids, fibres and prismatic calcium oxalate crystals as microscopic characters. The percentage weight loss on drying was 6.1 ± 0.15 while the water and alcohol extractive values were1.87 ± 0.04 and 0.59±0.03% respectively. The total ash value was 28.49±0.89 % while the water soluble and the acid insoluble ash values were 2.31± 0.19 and 9.93±0.2% respectively. The preliminary phytochemical results on the stem bark include saponins, tannins, flavonoids and no alkaloids and anthracene derivatives. At 5 mg/kg, the methanol extract of the stem bark produced 6.6±1.2 mmHg fall in mean arterial blood pressure with the effect more pronounced on the systolic than the diastolic blood pressure. At 10 mg/kg, the reduction in the blood pressure was 15.66±2.9 mmHg after which higher doses did not produce corresponding significant decrease in the blood pressure. Each dose administered was accompanied by corresponding reduction in the heart rate indicating the probable effect of the extract on the myocardium. The results showed that the stem bark of F. exasperata also possess hypotensive effect like the leaf reported earlier. Keywords: Ficus exasperata, Pharmacognostic parameters; Hypotensive effectsJournal of Pharmacy and Bioresources, Vol. 6 no. 2, pp. 43-49 (September 2009)

Pharmacognostic evaluation of the leaves of Sida acuta Burm.F. (Malvaceae)

Sida acuta Burm F. (Malvaceae) is an erect, branched small perennial herb or small shrub growing abundantly in Nigeria. In the Southern part of Nigeria, the plant is used to hasten delivery. In Nicaragua, the decoction of the entire plant is taken orally for asthma, fever, aches and pains, ulcers and for venereal diseases. The Pharmacognostic profiles such as phytochemical, macroscopical, microscopical, chemomicroscopical, and quantitative evaluations were carried out on the powdered leaves and anatomical sections of the fresh plant. The phytochemical analysis of Sida acuta powdered leaves revealed the presence of cardiac and saponin glycosides, flavonoids and alkaloids. The leaves are simple and alternate in arrangement, green in colour, and pubescent. Each leaf is shortly petiolate possessing a lanceolate lamina with a serrated margin and an acute apex. The powdered drug was subjected to microscopical examination. The stomata are anisocytic, epidermal cells are wavy, numerous unicellular non-glandular trichomes are present, and there are prismatic crystals of calcium oxalate, fragments of lignified fibres and simple starch grains. Chemomicroscopical tests on the powder showed the presence of lignin, starch, calcium oxalate and mucilage. This investigation also reports the palisade ratio (10.00 -11.80 -15.0 + 0.49), the stomata number ( 9.00-17.20-31.00 + 2.14) for the lower epidermis and 3.00- 7.10-12.00 + 0.94) for the upper epidermis, the stomata index (18.37-31.00-32.00 + 2.88 for the lower epidermis and 8.00-15.80-23.01 + 1.90 for the upper epidermis), the vein islet number (36.00-38.10-42.00 + 1.10 ), the vein termination number (14.00-19.10-24.00 + 1.03 ), the total ash values (8.63 + 0.07 % w/w ), the acid insoluble ash values (0.65 + 0.06 % w/w ),the moisture content (9.47 + 0.18 % w/w),the water soluble extractive values (2.93 + 0.46 % w/w) and the alcohol soluble extractive value (1.35 + 0.08 % w/w ) for the leaves of Sida acuta. This study thus provides a monograph on the plant for its proper identification and detection of adulteration /substitution. Keywords: Sida acuta leaves, Pharmacognostic profile.JOPAT Vol. 12 2007: pp. 56-65

Controle farmacognóstico das raízes de Heteropteris aphrodisiaca O. Mach. (Malpighiaceae)

The roots of Heteropteris aphrodisiaca, called no-de-cachorro (dog-knot) for their morphological similarity to the canine penis, are used in popular medicine as an aphrodisiac or stimulant, and to treat dysentery. The objective of the present study was to characterize these roots morphoanatomically and physico-chemically. For the analyses, histological slides were prepared, and aqueous, hydro-ethanol, and ketone extracts were analyzed, from root samples collected in the state of Mato Grosso, in different seasons of the year. The roots are tuberous, cylindrical, and covered with a striated suber. The cortex, composed of parenchymatous tissue, has no sclerified elements, but shows abundant druses and prismatic crystals of calcium oxalate, as well as idioblasts containing polyphenols. In the secondary xylem, gelatinous fibers are abundant, typical for the roots of species of the Brazilian cerrado (savanna). The physical and chemical analyses revealed greater losses through desiccation in the samples collected in spring and summer. Water was the best extraction liquid. Total ash content of the samples ranged from 3.4% in summer to 5.3% in autumn. Total phenol content was higher in spring (10.2%), suggesting this season as the most appropriate to harvest the plant drug. Chromatographic analyses through TLC and HPLC were employed using the flavonoids neoastilbin, astilbin, and isoastilbin as markers. The Rf values were 0.60, 0.68 and 0.74, and the retention time were 16.44, 16.91 and 18.08 min, respectively.

Comparative studies on Khaya. A. Juss (Meliaceae) in Nigeria

Comparative phytochemical, microscopical and chemomicroscopical studies were carried out on the genus Khaya with the aim of obtaining useful characters for the identification and delimitation of species boundaries. Tannins and saponins were present in all the species while phenols were detected in all except K. grandifoliola. Protein and anthraquinones were present in the bark of all the species. Carbohydrate is present in all the species except in the bark of K. ivoriensis. Flavonoids and phlobatannins were absent in all the taxa. Microscopical examination of the powdered bark revealed different types and shapes of lignified sclereids, abundant distribution of prismatic calcium oxalate crystals, druses, lignified cork-cells, fibres, medullary rays and parenchyma cells which may contain starch grains.

Anatomy of the pericarp and seed-coat of Lithraea molleoides (Vell.) Engl. (Anacardiaceae) with taxonomic notes

The aim of the present work was to record anatomical data for the fruit and seed of Lithraea molleoides (Vell.) Engl, and compare the results with those for L. brasiliensis and the genera Schinus and Rhus. The L. molleoides fruit was a drupe with a friable and lignified exocarp. The mesocarp was parenchymatous with large secretory canals associated with vascular bundles. The endocarp consisted of four layers: an outer layer of polyhedral cells with prismatic crystals of calcium oxalate, and three inner layers of sclereids in a palisade arrangement. The ovule was anatropous, unitegmic, and crassinucelate. In the chalazal region, a cup-like zone of tanniniferous parenchymal cells formed the hypostase. The developing seed had a circinotropous-like shape, that originated through curvature of the long, coarse funicle that surrounded the tegument and embryo sac. The ripe seed was endotestal with bar-like thickenings or pittings in the cell walls.

Ontogeny and Structure of the Pericarp of Schinus terebinthifolius Raddi (Anacardiaceae)

The fruit of Schinus terebinthifolius Raddi is a globose red drupe with friable exocarp when ripe and composed of two lignified layers: the epidermis and hypodermis. The mesocarp is parenchymatous with large secretory ducts associated with vascular bundles. In the mesocarp two regions are observed: an outer region composed of only parenchymatous cells and an inner region, bounded by one or more layers of druse-like crystals of calcium oxalate, composed of parenchymatous cells, secretory ducts and vascular bundles. The mesocarp detaches itself from the exocarp due to degeneration of the cellular layers in contact with the hypodermis. The lignified endocarp is composed of four layers: the outermost layer of polyhedral cells with prismatic crystals of calcium oxalate, and the three innermost layers of sclereids in palisade.

Ultrastructural study on the formation of sclereids in the floating leaves of Nymphoides coreana and Nuphar schimadai

The formation of star-shaped sclereids in the floating leaves of Nymphoides coreana and Nuphar schimadai was studied microscopically. These foliar sclereids were associated with the aerenchyma and found as the form of idioblast. The outer surface of mature sclereids was smooth in Nymphoides, but with many prismatic calcium oxalate crystals in Nuphar. However, the early morphogenesis of these two kinds of sclereids was similar. The sclereid initials were distinguished from the neighboring cells by their distinctly large nucleus. The expanding sclereid initials were constrained by the neighboring cells. Crystal formation in young sclereids of Nuphar started near the cessation of sclereid expansion. The crystals were bounded by crystal sheath and located in crystal chambers between the primary cell wall and plasma membrane. Calcium antimonate precipitates were found, especially on the crystal sheaths as well as between the plasma membrane and the primary cell walls. The crystal chambers have a paracrystalline appearance connected with the crystal sheath and the plasma membrane. After formation of crystals, the secondary wall was deposited and then the crystals became embedded between the primary and secondary walls. The possible functions of the foliage sclereids and the plans for further investigation are discussed.

The Generic Position of Protorhus namaquensis Sprague (Anacardiaceae): Evidence from Fruit Structure

In Protorhus namaquensis the outer epidermis of the ovary forms the exocarp. At maturity it is uniseriate and consists of palisade-like parenchyma cells and modified stomata (MS). A cuticle, extensive cutinization of the outer cell walls and starch also characterize the exocarp. The mesocarp develops from the ground tissue of the ovary wall and includes an outer zone of large-celled tanniniferous parenchyma, secretory ducts associated with some of the vascular bundles, prismatic crystals of calcium oxalate and brachysclereids. The inner epidermis of the ovary undergoes successive periclinal divisions whose derivatives form the mature endocarp. It is stratified and tetraseriate, comprising successive layers (from mesocarp inwards) of crystalliferous cells, brachysclereids, osteosclereids and macrosclereids. The morphology of the female flower, and the fruit structure of P. namaquensis are compared with that of P. longifolia (lectotype of the genus and only other African species) and species of Ozoroa. We present abundant evidence that P. namaquensis should be associated with some members of the genus Ozoroa , rather than with P. longifolia. The new combination, Ozoroa namaquensis (Sprague) Von Teichman & Van Wyk, is proposed. Characters of the perianth and pericarp, inter alia the occlusion of the pores of most MS, are considered adaptations of the species to its harsh semi-desert habitat.

Calcium Oxalate Crystal Formation in the Bean (Phaseolus vulgaris L.) Seed Coat

The formation of calcium oxalate crystals in the developing bean seed coat was investigated by light, polarization, transmission, and scanning electron microscopy. Crystals first form in isolated lacunar parenchyma cells near the hilum, later in cells of subhilar tissue, and finally in hypodermal sclereid cells The initiation and development of crystals were studied in hypodermal sclereid cells Prior to crystal formation, young sclereid cells become highly vacuolate. Fibrillar material, as well as large vesicles apparently of cytoplasmic origin, appear in the vacuoles. Fusion or close association of these vesicles results in the formation of electron-dense bodies and membrane-like compartments (crystal chambers) within the vacuoles. Crystallization then commences within these chambers. Symmetrical prismatic twin crystals of calcium oxalate of two types form: kinked and straight twin crystals. The presence of an ordered substructure in crystal chamber sheaths indicates possible nucleation sites where crystallization occurs. Electron-dense bodies and fibrillar material within the vacuoles seem to be closely associated with crystal development. Mitochondria and plastids, the latter becoming transformed into crystalloplastids, also appear to be implicated in the crystallization process. Crystal growth is accompanied by thickening of cell walls which make contact with the crystals and begin to grow around them. After maximum crystal size and cell wall thickness have been attained, the remaining protoplast degenerates. Crystals in mature sclereid cells, surrounded by thick cell walls, could enhance the protective role of the bean seed coat.

Development of epidermal crystals in leaflets of Stylosanthes guianensis (Leguminosae; Papilionoideae)

In developing leaflets of Stylosanthes guianensis (Aubl.) Sw., twin prismatic calcium oxalate crystals form in adaxial and abaxial epidermal crystal idioblasts. These cells eventually die and collapse, leaving the crystals embedded in a matrix of cutin and cell-wall materials. Adaxial crystal idioblasts develop above large conical cells that, in turn, are interspersed among smaller, multiple-layered palisade parenchyma. Abaxial crystal idioblasts develop beneath a uniseriate layer of large horizontally branched cells abutting the abaxial epidermis. Spongy parenchyma occupies the middle mesophyll above the layer of branched cells. The abaxial crystals and the branched cells of the lowermost mesophyll develop simultaneously. Adaxial crystals and the conical cells develop later and in conjunction with each other. In mature leaflets, the adaxial and abaxial crystals and their associated collapsed crystal idioblasts form networks, the interstices of which are occupied by either single stomates and accompanying epidermal cells (adaxial) or clusters of stomates and accompanying epidermal cells (abaxial). Epidermal crystals are known from other Leguminosae; however, to our knowledge this is the first report where epidermal crystal development involving cell death and collapse is correlated with two types of specialized mesophyll cells.

Oxalic acid and calcium oxalate produced by Leucostoma cincta and L. persoonii in culture and in peach bark tissues

Oxalic acid and crystals of calcium oxalate were produced during growth of Leucostoma cincta and L. persoonii on potato dextrose agar and in peach bark tissues. The identification of calcium oxalate was based on solubility characteristics, the results of KMnO4 titration, positive staining with silver nitrate – dithiooxamide, and crystal morphology as observed with light and scanning electron microscopes. Oxalic acid was detected by gas chromatography. This is the first report of oxalic acid production by both Leucostoma species causing peach canker. Calcium oxalate crystals observed on or near hyphae in culture were similar to crystals in artificially inoculated peach bark tissues. Addition of oxalic acid solutions alone to inner bark tissues caused maceration and necrosis. These results indicate a role for oxalic acid in the early stages of pathogenesis by Leucostoma spp. Tetragonal (bipyramidal) and prismatic calcium oxalate crystals formed on bark wounds treated with oxalic acid solutions were similar to those observed in infected tissues and in culture media amended with oxalic acid.