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Pharmacognostic Studies on Ormocarpum sennoides (Willd.) DC.
Published in Parimelazhagan Thangaraj, Phytomedicine, 2020
M. M. Sudheer Mohammed, A. Narayanasamy, S. Mahadevan
The stem is roughly circular. It consists of a thin, intact layer of epidermis and narrow cortex comprised of elliptical parenchyma cells. Tannin- and oil-filled cells and sclerenchyma cells are presented in the cortex. The vascular cylinder is thick and hollow and encloses wide pith. The phloem cells are compressed. The xylem includes vessels and narrow fibers. The vessels are wide, circular, and thin-walled. The pith is slightly angular in outline, and the cells are circular, thin-walled, and often filled with starch grains (Figures 11.3 and 11.4).
Abies Spectabilis (D. Don) G. Don (Syn. A. Webbiana Lindl.) Family: Coniferae
Published in L.D. Kapoor, Handbook of Ayurvedic Medicinal Plants, 2017
Transverse section of the stem is pentagonal in outline with fairly prominent angles under which collenchyma lies. The epidermis is a single layer of oblong rectangular cells with outer well-developed tangential wall. The cortex is narrow, composed of three to four layers of chlorenchymatous cells. Endodermis is not discernible. Vascular bundles are present underneath the ridge; the bundles are collateral, endarch, and open. The xylem is composed of vessels, tracheid, fibers, and xylem parenchyma. The protoxylem elements are tracheids with annular or spiral thickening.
Microscopical Characters of the Medicinal Species of Bupleurum in China
Published in Sheng-Li Pan, Bupleurum Species, 2006
The ring of cambium cells is not obvious. The secondary xylem holds the main part of the root. The vessels are varied in diameter and accompanied by parenchyma cells. Spiral vessels and reticulated vessels are the chief ones in the secondary xylem (Figure 3.2). Annular vessels can be found in the primary xylem, which otherwise is not obvious. Some species have pitted vessels in the secondary xylem, e.g., B. chinense, B. smithii var. parvifolium, B. rockii, B. bicaule, B. angustissimum, B. sichuanense, and B. wenchuanense. Fibers occur in secondary xylem of most species. The xylem fibers are arranged in one or two discontinuous rings. In very few species, the xylem fibers can be in up to five to seven rings, such as in B. krylovianum or B. rockii. Pan et al. (1996, 2002) observed the root transverse sections of 22 species from Bupleurum genus. Their differences are presented in Table 3.1.
In vitro hepatic metabolism of the natural product quebecol
Published in Xenobiotica, 2023
Maple syrup is produced by concentrating the sap from Acer maple tree species via thermal evaporation (Perkins and van den Berg 2009). During this process, the intensive heating facilitates the formation of distinct bioactive compounds that are not naturally present in the xylem sap (Ball 2007). Maple syrup has shown a wide range of biological effects including antiproliferative (González-Sarrías et al. 2012a, 2013; Yamamoto et al. 2015), anti-inflammatory (González-Sarrías et al. 2012b; Nahar et al. 2014; Rose et al. 2021), and antioxidant (Legault et al. 2010; Li and Seeram 2010; Liu et al. 2017). Recently there has been an interest in the isolation, identification, and biological investigation of phenolic compounds from maple syrup products (Ball 2007; Li and Seeram 2010; Y. Liu et al. 2017). As part of these investigations, the novel phenolic compound quebecol was isolated and characterised (Li and Seeram 2011).
Global impact of trace non-essential heavy metal contaminants in industrial cannabis bioeconomy
Published in Toxin Reviews, 2022
Louis Bengyella, Mohammed Kuddus, Piyali Mukherjee, Dobgima J. Fonmboh, John E. Kaminski
Heavy metals loading into xylem vessels occurs via HMA2 and/or HMA4 proteins (Park and Ahn 2017), and sequestration results from the binding of chelating proteins and transporters (Uraguchi et al. 2009). Heavy metals trafficking from xylem to phloem is mediated by PHT1:1, PHT1:4, and heavy metal ATPase and cation exchanger 2 (Wong and Cobbett 2009). Recently, Ahmad et al. (2016) identified two important HMs responsive genes, glutathione-disulfidereductase (GSR) and phospholipase D-α (PLDα) in C. sativa that are overregulated by reactive oxygen species (ROS) produced under stress. In another study, an increase in phytochelatin and DNA content was observed when C. sativa was subjected to heavy metal stress conditions (Citterio et al. 2003). The cannabis genome consists of 54 GRAS transcription factors (involved in growth and development) that regulate 40 homologous GRAS genes under cadmium stress (Ming-Yin et al. 2020). Thus, we suggest the application of reverse genetics to silence HMs transporters in the developmental process of next-generation domesticated cannabis. This approach has the potential to mitigate the intrinsic phytoremediation propensity, ensure consumer safety, and boost the cannabis bioeconomy. However, to develop HMs hyperaccumulating cannabis strains for applied biotechnologies such as phytoremediation, phytomining, and pre-cultivation cleaning of farmland, exploring evolved and adapted landraces from global HMs hotspots (Table 1) could facilitate the process. Cannabis landraces from global HMs hotspots should be studied for their unique physiological propensity to uptake, transport, and sequestrate HMs and avert extinction in extreme growing conditions.
Bio-acoustic signaling; exploring the potential of sound as a mediator of low-dose radiation and stress responses in the environment
Published in International Journal of Radiation Biology, 2022
Bruno F. E. Matarèse, Jigar Lad, Colin Seymour, Paul N. Schofield, Carmel Mothersill
Drought stress and predation constitute two of the major physiological stressors of vascular plants. Under drought stress some plants produce measurable bio-acoustic emissions (De Roo et al. 2016). The mechanisms for generating these signals are not fully understood but may involve the effects of decreasing hydrostatic pressure in xylem, leading to the production of ultrasonic sound emissions variously measured as >20 kHz (Tyree and Dixon 1983) and from 10 to 300 kHz (Laschimke et al. 2006). With rapidly decreasing pressure in the xylem, collapse of bubbles caused by cavitation has been suggested as one mechanism for the generation of sound, but an alternative hypothesis derived to explain the ‘violent acoustic activity’ detected in Ulmus sp. in response to drought stress, is release of energy from the xylem-adherent bubble system that normally contributes to water flow (Laschimke et al. 2006; Zweifel and Zeugin 2008; Gagliano et al. 2012a, 2012b; Gagliano 2013). Respiration and metabolic growth activity of the cambium is another method suggested to be involved (Zweifel and Zeugin 2008). The cambium is the portion between the xylem and phloem where cells are rapidly dividing and is responsible for secondary growth of stems and roots (Zweifel and Zeugin 2008; Schöner et al. 2016). At nighttime when the plant is subject to drought stress, the cambium has increased turgor pressure due to increased respiration. This increased pressure causes greater levels of carbon dioxide to enter the xylem, resulting in more gas bubbles and subsequent acoustic emissions. In the absence of drought stress and consequent xylem cavitation, young corn roots are able to produce clicking sounds under water – the reason for retaining or developing this mechanism is unknown (Schöner et al. 2016). It is apparent that a variety of plant species have developed mechanisms for sound production.