Tannin-containing Cells Research Articles

Microscopical Evaluation and TLC Analysis of Pluchea indica (L.) Less: Leaf, Stem, and Root

Pluchea indica (L.) Less is traditionally utilized to treat postpartum women in Indonesia. The plant has many pharmacological properties, so that it can be further developed as herbal medicine. In that development process, plant authentication is needed to ensure the quality of raw materials. A simple microscopical and thin-layer chromatography (TLC) analysis might be a way to authenticate the plant, but it has never been reported. So, this study evaluates the microscopical and TLC analysis for P. indica authentication in standardized herbal medicines production. Plant microscopic observation, fluorescence analysis, and polyphenol screening were conducted. n-Hexane, ethyl acetate, and methanol extracts of plant organs were then analyzed by TLC. Here, we reported that in microscopical analysis the simplicia of P. indica contains trichomes and tannin-containing cells. In addition, chlorogenic acid as a marker was present in TLC analysis by ethyl acetate-water-formic acid-acetic acid (8.5:1.5:1:1, v/v). The results of this evaluation might provide additional information in the identification, authentication, and quality control of P. indica as a raw material for herbal medicine.

Secretory structures in stems of five lianas of Paullinieae (Sapindaceae): Morphology and histochemistry

Paullinieae lianas are noteworthy for possessing cambial variants, so it is not surprising that the structure of the vascular system has been the focus of most of anatomical studies involving these plants. However, secretory structures remain understudied in the tribe and in the family Sapindaceae as whole. This study aims to characterize the secretory structures in the stems of five lianas of Paullinieae in order to better understand their morphology and histochemistry. Stem anatomy was analysed using light microscopy and the chemical composition of their secretory structures was determined histochemically. Three secretory structures were found: idioblasts, glandular trichomes and laticifers. Tannin-containing cells (idioblasts) are distributed throughout the stems. Glandular trichomes are capitate and have a complex mixture of phenolic compounds, tannins, proteins and polysaccharides. Laticifers occur in primary tissues, and are also observed in the secondary structure of Serjania pernambucensis Radlk.; they occur in regular and variant phloem (cambial variant), arranged in clusters due to divisions of pre-existing laticiferous cells. This phenomenon has not been reported previously. Additionally, this is the first detailed study of laticifers in primary and secondary structure of stems of lianas of Sapindaceae. The laticifers are articulated and non-anastomosing, containing the following chemical components: rubber, lipids, proteins, polysaccharides and terpenoids. Future studies might provide a broader understanding of the morphological diversity and the role of secretory structures in the tribe.

Pharmacognostical and Histochemical Studies on Apakva Kadali (Unripe Banana Fruit)

The unripe fruit of Musa × paradisiaca L., classically known as apakva kadali, belonging to the family Musaceae, is used as pa- thya in atisara (diarrhea), in grahani (irritable bowel syndrome), and agnimandya (loss of appetite). The unripe fruits are considered to be helpful in the management of diabetes mellitus. Being an important medicinal plant, the present investigation is an attempt to explore the pharmacognostical analysis and thin-layer chromatography fingerprint studies on the widely used Musa. × paradisiaca L. The studies revealed that unripe banana fruit showed the presence of small outer protrusion of papillae on the epidermis, abundant tannin-containing cells in the epicarp and mesocarp. Elongated air-spaced cells are surrounded by the parenchyma cells in the epicarp, abundant starch grains in the mesocarp portion, and acicular crystals of calcium oxalate in raphide bundles. To detect the location of various constituents of the drug, sections of unripe fruits were treated with various reagents, and studies showed the presence of phenols, protein, calcium oxalate, magnesium, starch, cellulose, calcium pectate, lignin, sulfated mucopolysaccharides, tannin, and silica contents. Phytochemical studies showed the presence of alkaloids, carbohydrates, phenols, proteins, starch, tannins, steroids, and saponins.

Seasonal development of phloem in Siberian larch stems

The seasonal development of phloem in the stems of Siberian larch (Larix sibirica Ldb.) was studied over two seasons on 50-60-year-old trees growing in a natural stand in the Siberian forest-steppe zone. Trees at the age of 20-25 years were used to study metabolites in differentiating and mature phloem elements, cambial zone, and radially growing xylem cells in the period of early and late wood formation. The development of the current-year phloem in the stems of 50-60-year-old trees started, depending on climatic conditions, in the second-third decades of May, 10-20 days before the xylem formation, and ended together with the shoot growth cessation in late July. Monitoring of the seasonal activity of cambium producing phloem sieve cells and the duration of their differentiation compared to the xylem derivatives in the cambium demonstrated that the top production of phloem and xylem cells could coincide or not coincide during the season, while their differentiation activity was always in antiphase. Sieve cells in the early phloem are separated from those in the late phloem by a layer of tannin-containing cells, which are formed in the period when late xylem formation starts. The starch content in the structural elements of phloem depends on the state of annual xylem layer development. The content of low molecular weight carbohydrates, amino acids, organic acids, and phenols in phloem cells, cambial zone, and xylem derivatives of the cambium depends on the cell type and developmental stage as well as on the type of forming wood (early or late) differing by the cell wall parameters and, hence, by the requirement for assimilates. Significant differences in the dynamics of substances per dry weight and cell were observed during cell development.

Seasonal development of phloem in scots pine stems

The formation of phloem was studied for two years in stems of 50 to 60 year old trees of Scots pine (Pinus sylvestris L.) growing in nature. The development of phloem of the current year begins 10 to 20 days before the xylem formation and is completed with the termination of shoot growth in the end of June. Observations over the seasonal activity of cambium producing sieve-like cells of phloem and duration of their differentiation as compared to the xylem derivatives of cambium have shown that the maxima of formation of phloem and xylem cells could coincide or not coincide by season, while the activities of their differentiation were always at antiphase. The sieve-like cells of early phloem were separated from those of late phloem by a layer of tannin-containing cells, which are formed simultaneously with the formation of late xylem cells by the cambium. Seasonal dynamics of accumulation of starch grain in structural elements of the phloem is related to the xylem development. The content of metabolites in differentiating and mature phloem elements, in the cambium zone, and in the xylem cells growing in the radial direction depended on cell specificity, stage of their development, and type of forming wood, early or late, which differ in the cell wall parameters and, hence, requirement of assimilates. Significant differences were described between the content of low molecular weigh carbohydrates, amino acids, organic acids, and phenol compounds using two methods of calculation: per dry weight and per cell.

Sn, a maize bHLH gene, modulates anthocyanin and condensed tannin pathways in Lotus corniculatus.

Anthocyanins and condensed tannins are major flavonoid end-products in higher plants. While the transactivation of anthocyanins by basic helix-loop-helix (bHLH) transcription factors is well documented, very little is known about the transregulation of the pathway to condensed tannins. The present study analyses the effect of over-expressing an Sn transgene in Lotus corniculatus, a model legume, with the aim of studying the regulation of anthocyanin and tannin end-products. Contrary to expectation, effects on anthocyanin accumulation were subtle and restricted to the leaf midrib, leaf base and petiole tissues. However, the accumulation of condensed tannin polymers was dramatically enhanced in the leaf blade and this increase was accompanied by a 50-fold increase in the number of tannin-containing cells in this tissue. A detailed analysis of selected lines indicated that this transactivational phenotype correlated with high steady-state transcript levels of the introduced transgene and the introduction of a single copy of the CaMV35S-Sn construct into these clonal genotypes. While the levels of condensed tannins in leaves were increased by up to 1% of the dry weight, other major secondary end-products (flavonols, lignins and inducible phytoalexins) were unaltered in transactivated lines. These results give an initial insight into the developmental and higher-order regulation of polyphenolic metabolism in Lotus and other higher plant species.

Condensed tannins in sainfoin. II. Occurrence and changes during leaf development

A histological study examined condensed tannin (CT) formation in plant tissue samples taken from the meristematic area of very young sainfoin (Onobrychis viciifolia Scop.) seedlings and from leaflets sampled at various stages of development in mature plants growing in the greenhouse. Light and electron microscopy revealed no CT in the seedling meristem and leaf primordia, but CTs were seen very early in leaf development forming first in the vacuoles of discrete cells of the abaxial subepidermal layer when the leaflets were recognizable, but still folded. Immature leaflets collected from the growing point of a mature sainfoin plant show similar CT formation with the abaxial cell vacuoles filled with CT when the new leaves have reached the 90°-fold stage. As the leaflets unfold and mature, CTs begin to appear in the vacuoles of small, but discrete cells in the adaxial subepidermal layer while the tannin-containing cells in the abaxial subepidermal layer begin to lose CT. The CT continues to increase in the adaxial layer until typical enlarged tannin idioblasts or sacs are observed at full leaflet expansion and maturity. By this stage, the vacuoles in the abaxial layer are almost empty. In senescing leaflet samples collected from the leaf rachis attached to the last and second to last node near the base of the plant, the cells in both subepidermal layers have lost the majority of the CT that was originally formed. At senescence all tannin-containing cells appear as empty shells. We speculate that a finite amount of CT is formed in the two subepidermal layers of new leaves at different stages of early leaf development, does not increase during the mature phase, and is catabolized in older leaves and during senescence. Key words: condensed tannins, sainfoin, Onobrychis viciifolia, leaf development.

Anatomy of the Legume Nodule Cortex With Respect to Nodule Permeability

We describe the anatomy of the cortex of a range of legume nodules (43 species of 31 genera of 13 tribes, principally of the Papilionoideae). To our knowledge, the nodule anatomy of 19 of the genera examined (30 species) was previously unreported. All nodules have a layer(s) in the inner cortex with distorted radial walls ('boundary layer') and occlusions of the intercellular spaces within the middle cortex. The 'nodule endodermis' as defined by Frazer (1942) was difficult to identify unless modified by sclerification or tannin deposition. In other species, the outer cortex contains a well developed periderm, often with several layers of tannin-containing cells. When present, sclereids contain a living cytoplasm, and are interspersed with parenchyma cells to form a water-filled barrier c. 50 μm in width about the nodule. Nodule sclereids are apparent within 5 days of inoculation in Glycine max. Sclerification of the common endodermis did not significantly increase following growth at 50 or 80% rhizosphere pO2. We suggest that the intercellular space deposition, the common endodermal layer and the periderm layer will act as a fixed resistance to gas diffusion into the nodule, allowing for a fine control of a variable resistance (boundary) layer within the inner cortex.

Condensed Tannin Formation byAgrobacterium rhizogenesTransformed Root and Shoot Organ Cultures ofLotus corniculatus

Root cultures of Lotus corniculatus L. cv. Leo transformed with Agrobacterium rhizogenes (C58Cl-pRi 15834) grew rapidly in liquid medium when cultured in the dark and produced large numbers of shoots when illuminated. The shoots, which could be regenerated to produce fertile plants, were maintained in liquid medium as shoot-organ cultures. The accumulation and cellular distribution of condensed tannins was determined during the growth of these root and shoot organ cultures and in primary callus from non-transformed expiants. Root and shoot cultures predominantly accumulated insoluble polymeric tannins which yielded both cyanidin and delphinidin on hydrolysis at ratios equivalent to control plants. Methanol-soluble vanillin-positive compounds were isolated but no free oligomeric proanthocyanidins, monomeric flavans or dihydroflavonols were detected in these extracts. Condensed tannin accumulation was linearly related to root growth and had a similar spatial distribution in 'tannin' cells in roots and leaves as compared to control plants. Tannin-containing cells were absent from meristematic cells of the root tip and root/shoot interface. Primary callus cultures failed to accumulate condensed tannins on media containing auxins, and exogenously supplied auxins were found to inhibit tannin accumulation by transformed root and shoot cultures.

Leaf Structural Peculiarities in Sarcopoterium spinosum, a Seasonally Dimorphic Subshrub

Extensive investigations on the anatomy of the two leaf types in a seasonally dimorphic subshrub revealed interesting variations between summer and winter leaves. Summer leaves of Sarcopoterium spinosum possess a thick epidermis composed of tannin-containing cells and large amounts of mucilage secreted through the inner periclinal walls towards the mesophyll

Presence of myelin-like structures in tanniferous vascular parenchyma cells ofSalix dasyclados Wim.

In the cambial region ofSalix dasyclados plants, extensive spherical formations of myelin-like lamellar configurations were found during the transit period between winter dormancy and reactivation of growth in early spring. The lamellar structures occurred in parenchyma cells containing tannins and were associated with spherosomes. Cytomembranes in tannin-containing cells appeared with negative contrast on electron micrographs, indicating the presence of tanniferous substances in the cytoplasm.

A Systematic and Evolutionary Study of Oenothera (Onagraceae): Seed Coat Anatomy

On the basis of a study of 32 of the 124 species representing the 14 sections of Oenothera, we find that the seed coats exhibit considerable anatomical diversity, particularly the exotesta, mesotesta, and endotesta. Features throughout the genus are: (1) endotegmen is one cell thick and persistent and (2) consists of longitudinally elongate, tannin-containing cells; (3) exotegmen consists of longitudinally elongate, thick-walled, pitted, lignified fibers; and (4) endotestal cells contain crystals. Unequivocal relationships are demonstrated for species with essentially identical seed features: (1) between section Kleinia and section Oenothera subsection Raimannia; and (2) among sections Hartmannia, Kneiffia, Xylopleurum, and Anogra. A cladistic analysis, using seed anatomy data, indicates that (1) O. havardii differs in several characteristics from members of section Gauropsis and should be excluded; and (2) seed anatomy of O. maysillesii differs in several features from the other species of subsection Emersonia; these same differences are shared with sections Ravenia, Contortae, Eremia, and Pachylophus, indicating that O. maysillesii is their sister group. The analysis indicates an early divergence of Oenothera into two major lineages: (1) species with thick endotesta (sections Contortae, Eremia, Kleinia, Oenothera, Pachylophus, and Ravenia); and (2) species with radially flattened endotestal cells (sections Anogra, Gauropsis, Hartmannia, Kneiffia, Lavauxia, Megapterium, Paradoxus, and Xylopleurum). Subsequent changes in seeds of both lineages include multiplication of the fibrous exotegmen, development of a crushed mesotesta or multiplication of the cell layers of the mesotesta, and specialization of the exotesta involving various radial cell enlargements. Diversification of the first lineage has involved changes in seed anatomy that correlate with ecological shifts, while to a much greater extent the evolution of the second lineage has not. Outer layers of the seed appear to be more open to adaptive modifications than inner ones.

Systematic Anatomy of the Flower and Fruit of Corokia

Corokia, a genus of shrubs of New Zealand, eastern Australia, and certain Pacific islands, was first placed in Rhamnaceae, later in Cornaceae, and most recently next to Argophyllum, subfamily Escallonioideae, in Engler's monograph of the Saxifragaceae. Most manuals still list Corokia under Cornaceae from which it is readily excluded by several characters, including pluricellular T-shaped trichomes, ligulate petals, vascular bundles running longitudinally through the center of the inferior gynoecium, histology and germination of the woody endocarp, and a conspicuous subepidermal layer of tannin-containing cells. Corokia collenettei, endemic to the isolated island Rapa, retains the most primitive floral characters of the genus. Anatomical comparison of Corokia flowers with flowers of Argophyllum shows similarities that probably indicate affinity, but the relation of these two genera to others in Engler's subfamily Escallonioideae is unclear. Engler's inclusion of Berenice and Carpodetus with Corokia and Argophyllum in a tribe Argophylleae seems especially artificial.

DIVISION OF STARCH‐CONTAINING CELLS

DIVISION OF CERTAIN CELLS whose contents indicate a state of physiological specialization has been reported recently by several investigators. Bloch (1947) noted the retention of the power of multiplication for a considerable time after differentiation by some idioblasts such as oil cells, tannin cells, and cells containing crystals of calcium oxalate. In Ricinus the secretory cells whose contents give the reactions of tannin and fatty acids divide along with the rest of the ground parenchyma cells in the intercalary rib meristem of the internodal regions (Bloch, 1948). Ball (1950) observed that tannincontaining cells as well as clear cells could function as initials of files of cells at the margins of callus cultures of Sequoia sempervirens. The present paper reports observations on division of the starch-containing cortical parenchyma cells of young potato tubers (var. Irish Cobbler). Multiplication of these cells occurs during the normal development of the young tuber. Their division is of interest not only because they are physiologically differentiated cells but also because of the prevalent idea that division of starch-containing cells is preceded or accompanied by digestion of the starch grains. This idea is supported by the observations of some investigators on the development of wound periderm in the potato. Priestley and Woffenden (1923) observed that within a few days of the formation of a suberin or fatty deposit on the cut surface of a potato tuber, the cells just below the surface rapidly lose their starch content and the cork meristem then arises within this region. Steward et al. (1932) found that potato discs respiring in air showed extensive starch disappearance to a depth of 0.8 mm. below the cut surface and the development of a cork cambium in this surface region of starch depletion. Their figure 8A shows that the starch depletion in the surface region was partial rather than complete. One brief reference to the division of potato tuber cells that contain starch grains has been found in the literature. Nemec (1899) noted that the spindle fibers in the vicinity of vacuoles or starch grains adjacent to the nucleus were shorter t-han the other fibers and he figured two large starch grains near a dividing nucleus. Division of cells containing starch would be expected to take place in any developing homogeneous tissue in which starch storage begins before enlargement of that tissue by cell division has ceased. It seems probable, therefore, that division of starch-containing cells is not