Epidermal and anatomical studies on Chrysophyllum L. (Sapotaceae) species of South-Eastern Nigeria

The epidermal characters of leaves and anatomical characters of petioles and young stems of some members of the genus Chrysophyllum, viz. C. albidum, C. perpulchrum, C. cainito, and C. delevoyi were analyzed to determine their diagnostic features. Paracytic stomata, crystal sand, prismatic crystals, secretory canals occurred in all the species. All the species are hypostomatic except C. perpulchrum. The midribs of all species have an open semi-circular vascular system except in C. cainito with a closed system. Midrib and petiole of C. albidum and C. cainito have non-glandular T-shaped trichomes. Accessory bundles are only seen in the petioles of C. delevoyi, and in the midribs of C. albidum and C. cainito. The midrib and petiole of C. delevoyi and C. albidum have a central bundle. Laticifers, prismatic and sand crystals occur mainly in the cortical cells, pith cells, xylem, phloem, and mesophyll. Lamina of all species studied showed uniseriate epidermis except C. cainito which has two layers of the adaxial epidermis. The stomatal index, the ratio of the spongy to palisade mesophyll thickness, the ratio of cortex thickness, outline, number, and arrangement of the vascular bundles in the midrib, petiole, and young stem differ and are valuable diagnostic features in Chrysophyllum. Bangladesh J. Plant Taxon. 28(1): 217-231, 2021 (June)

Anatomical traits of Artemisia umbelliformis subsp. eriantha (asteraceae) alpine glacial relict from Mt. Durmitor (Montenegro)

In this study, the vegetative anatomy of Artemisia umbelliformis subsp. eriantha, a Central European alpine glacial relict, wild-growing on Mt. Durmitor (Montenegro) was examined for the first time. The aim was to investigate the general anatomy and particular anatomical traits which might have possible taxonomic value. Microscopic slides were prepared according to the standard histological procedures. The adventitious young root showed a primary structure, while the older root showed a secondary structure with a well-developed periderm on its surface. The rhizome showed a primary structure with elements of a secondary structure (periderm). The stem cross section is characterized by a round shape with a well-developed periderm at certain stages, and collateral vascular bundles arranged in a circle. The petiole is concave in shape with a single-layered epidermis and parenchyma tissue with one large and two small vascular bundles. Druses and rhombohedral crystals are observed inside some petiole parenchyma cells. The leaf lobe cross section has an oblong-linear shape and is isolateral and amphistomatous in structure. The anticlinal walls of the leaf epidermal cells are sinuate. Secretory canals are present in the root cortex parenchyma (endodermal secretory canals) and the rhizome cortical parenchyma. The stem, petiole and leaf lack secretory canals. The stem and leaf are covered with T-shaped non-glandular and glandular trichomes. The taxonomic value of the analyzed characteristics is briefly discussed.

Variation in oleoresin yield and anatomical traits among Sindora glabra populations in Hainan, China

Key message Geography and tree diameter were the major factors in determining oleoresin yield in Sindora glabra. The tangential diameter and area of secretory canals are reliable indicators of the oleoresin amount. Abstract Sindora glabra is a native tropical plant of China that exudes copious amounts of oleoresin from wounds on the stem. Elucidation of the mechanism affecting the oleoresin yield is of particular importance for development and selection of superior germplasm. In this study, the variation in oleoresin yield and anatomical traits of the stem of S. glabra were investigated in four main natural populations in Hainan. The results showed that annual oleoresin yield varied considerably among populations. The oleoresin yield exhibited an increasing trend with the increment of tree stem diameter until the diameter was over 80 cm. Moreover, oleoresin production in the wet season was higher than in dry season. The analysis of oleoresin chemical composition indicated that the four populations belong to the same chemotype despite the amount of four types of sesquiterpenes varying greatly among areas. Anatomical analysis revealed that quantitative traits of secretory canals including tangential diameter, area, density and frequency were significantly different among populations and tree diameters. Furthermore, the tangential diameter and area of secretory canals were positively correlated with oleoresin yield. These results suggested that the tangential diameter and area of secretory canals are reliable indicators of the oleoresin amount and can be used for selection purposes in S. glabra.

Stem and leaf structure of Searsia erosa (Thunb.) Moffett (Anacardiaceae) with systematic, ecological and ethnobotanical implications

The anatomy of stems and leaves of the southern African evergreen shrub Searsia erosa (Anacardiaceae) was studied. This species shows the suite of typical traits of Anacardiaceae, such as the presence of secretory canals in the cortex, secondary phloem, wood rays and vascular bundle of leaf midrib, pericyclic fibres in nearly continuous bands, compound sieve plates on oblique walls, simple perforation plates, alternate intervessel pitting, and septate libriform fibres. Like other Searsia species, S. erosa has abundant sclereids in non-conducting secondary phloem, multicellular peltate glandular trichomes on leaf epidermis, short vessel elements and minute intervessel pits; two latter characters are thought to be diagnostic for this genus. Unlike Asian species of Searsia, S. erosa lacks marginal axial parenchyma as well as prismatic crystals in axial parenchyma and in libriform fibres, but it shows the helical thickenings on vessel walls. The presence of the last trait in a southern African species agrees with association of helical thickenings with the regions that experience water stress. The tangential expansion of secondary phloem in S. erosa and probably in other Searsia species is mainly performed by considerable increase in volume of its cells by their sclerification. Such a way of bark growth in girth is out of scope of bark anatomists. Searsia erosa is distinctive from other congeneric species in its hypostomatous leaves with abundant glandular trichomes on adaxial side. This condition demonstrates a labor division between the adaxial side with glandular trichomes that may contribute to leaf protection, and the stomata-bearing abaxial side providing the gas exchange. Unlike most members of Anacardiaceae, the secretory canals of S. erosa produce the oleoresin containing terpenoids (essential oils) and lipids, but lack polysaccharides. The abundance of glandular trichomes and secretory canals producing terpenoids is a presumable reason of the use of S. erosa in traditional medicine by the Basotho people.

Tissue-Specific Metabolite Profiling on the Different Parts of Bolting and Unbolting Peucedanum praeruptorum Dunn (Qianhu) by Laser Microdissection Combined with UPLC-Q/TOF–MS and HPLC–DAD

Background: Qianhu is a traditional Chinese medicine. It is thought that Qianhu roots will harden after bolting and not be suitable for medicinal purposes. Bolting Qianhu and unbolting Qianhu are referred to as “Xiong Qianhu” and “Ci Qianhu,” respectively. In this study, the properties, microscopic and chemical characteristics of Ci Qianhu and Xiong Qianhu roots were compared using fluorescence microscopy, laser microdissection coupled with ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry, and high-performance liquid chromatography with diode-array detection. Results: Microscopy results showed that the area of secondary xylem in the root increased after bolting, with the cork and secretory canals showing strong fluorescence intensity. A total of 34 peaks, mostly pyranocoumarins, were identified in the tissues of Ci Qianhu and Xiong Qianhu. The secretory canals contained the highest variability of coumarins, whereas the secondary xylem contained the least coumarins. Moreover, seven coumarins, especially the pyran- coumarin, decreased after bolting. Generally, both before and after bolting, coumarin level was the highest in the bark, followed by the middle part, and the lowest in the inner part. Conclusion: Thus, it was indicated that the area of secondary xylem increased after bolting, however the coumarin variant and content decreased in the secondary xylem of Qianhu. The result shows that the quality of Qianhu decreases after bolting, which supports the viewpoint that Xiong Qianhu is not suitable for medicinal use.

Molecular Docking Studies of Coumarins Isolated from Extracts and Essential Oils of Zosima absinthifolia Link as Potential Inhibitors for Alzheimer’s Disease

Coumarins and essential oils are the major components of the Apiaceae family and the Zosima genus. The present study reports anticholinesterase and antioxidant activities of extracts and essential oils from aerial parts, roots, flowers, fruits and coumarins—bergapten (1); imperatorin (2), pimpinellin (3) and umbelliferone (4)—isolated of the roots from Zosima absinthifolia. The investigation by light and scanning electron microscopy of the structures of secretory canals found different chemical compositions in the various types of secretory canals which present in the aerial parts, fruits and flowers. The canals, present in the aerial parts, are characterized by terpene hydrocarbons, while the secretory canals of roots, flowers and fruits include esters. Novel data of a comparative study on essential oils constituents of aerial parts, roots, flowers and fruits of Z. absinthfolia has been presented. The roots and fruits extract showed a high content of total phenolics and antioxidant activity. The GC-FID and GC-MS analysis revealed that the main components of the aerial parts, roots, flowers and fruits extracts were octanol (8.8%), octyl octanoate (7.6%), octyl acetate (7.3%); trans-pinocarvyl acetate (26.7%), β-pinene (8.9%); octyl acetate (19.9%), trans-p-menth-2-en-1-ol (4.6%); octyl acetate (81.6%), and (Z)-4-octenyl acetate (5.1%). The dichloromethane fraction of fruit and flower essential oil was characterized by the highest phenolics level and antioxidant activity. The dichloromethane fraction of fruit had the best inhibition against butyrylcholinesterase enzyme (82.27 ± 1.97%) which was higher then acetylcholinesterase inhibition (61.09 ± 4.46%) of umbelliferone. This study shows that the flowers and fruit of Z. absinthifolia can be a new potential resource of natural antioxidant and anticholinesterase compounds.

Wood anatomy and growth ring boundaries of Copaifera lucens (Fabaceae)

ABSTRACTThe wood anatomy of Copaifera lucens Dwyer was studied with an emphasis on its growth ring boundaries. Growth rings are visible to the naked eye and demarcated by marginal parenchyma bands and, sometimes, by thick-walled fibers in the latewood. Secretory canals are associated with marginal parenchyma bands, but not all marginal parenchyma bands are associated with canals. Paratracheal parenchyma is vasicentric to lozenge-aliform. Rays are 1–4-seriate, heterocellular and non-storied. Vessels are visible to the naked eye, diffuse, predominantly solitary, some in multiples, sometimes filled with gums. Crystals present. Wood anatomical characteristics of C. lucens are in agreement with those previously reported for other species of Copaifera. In addition to what had already been described for C. lucens, we observed gelatinous fibers, and some bifurcate fibers, and extremely rare clustered vessels. The growth ring boundaries are well-defined in mature wood but less distinctive near the pith. There are also partial and confluent (wedging) rings, which are difficult to classify by anatomy only, but which represent false rings and complicate tree-ring analysis in this species.

Foliar architecture of some members of the tribe Senecioneae (Asteraceae) with a key for identification of the Mexican genera

The foliar architecture of 18 genera (Barkleyanthus, Digitacalia, Erechtites, Nelsonianthus, Packera, Pentacalia, Pippenalia, Pittocaulon, Psacaliopsis, Psacalium, Pseudogynoxys, Robinsonecio, Roldana, Senecio, Telanthophora, Tetradymia, Villasenoria and Werneria) of the tribe Senecioneae (Asteraceae) distributed in Mexico is described. The aim was to identify leaf characters to be used in the taxonomy and phylogenetics of the tribe, as well as a source to identify at the generic rank the genera distributed in Mexico. More than 400 specimens were revised and several leaves were cleared to analyze leaf venation patterns. Four patterns of primary venation (actinodromous suprabasal, paralelodromous, pinnate and radiate-palmate) and five patterns of secondary venation (brochidodromous, weak-brochidodromous, craspedodromous, mixed-craspedodromous and festooned-semi-craspedodromous) were identified. Terminal tracheids were observed only in veinlets of Pentacalia, Pseudogynoxys and Werneria. In addition, secretory canals and crystals occurred in several genera. Foliar architecture showed to be a useful tool to identify genera, an identification key based mostly on leaf architecture characters is provided.