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Bioactive Compounds in Marine Macro Algae and Their Role in Pharmacological Applications
Published in Parimelazhagan Thangaraj, Phytomedicine, 2020
Subramaniam Kalidass, Lakshmanan Ranjith, Palavesam Arunachalam, Amarnath Mathan Babu, Karuppasamy Kaviarasan
Plant growth hormones are available in seaweed extracts, which are used to induce plant growth and to improve the photosynthesis. Cytokinins are plant growth regulators that protect plants from temperature variations (Tarakhovskaya et al. 2007; Zhang et al. 2010), and these are synthesized by means of the bio-chemical modification of adenine. Other plant hormones are auxin, abscisic acid, and betaines that are found in macro algal extracts. Auxin functions to start the root formation and reduce its elongation, their concentration may vary, and it depends up on the species. Gibberellins play a major role to start seed germination and are formed in developing seeds from glyceraldehydes-3-phosphate. They were first identified in two brown algal extracts, such as a Fucus vesiculosus and Fucus spiralis (Tarakhovskaya et al. 2007). Abscisic acid is formed from carotenoids by more than 60 species of algae, and betaines are not usual plant hormones, which are also found in seaweed extracts (MacKinnon et al. 2010), and their role is to guard the plants from drought and frost (Craigie 2011). The brown algal extract, Ascophyllum nodosum, has a rich source of betaines (Khan et al. 2009; Craigie 2011).
Calcium and Cytokinin in Mosses
Published in R. N. Chopra, Satish C. Bhatla, Bryophyte Development: Physiology and Biochemistry, 2019
Initiation of cell division in plants is under the control of a class of compounds called cytokinins, N6-substituted adenines (see Reference 1 and references cited therein). I have recently postulated that these hormones may exert at least part of their effect on cells by modulating the intracellular calcium ion concentration ([Ca2+]i) in both a temporal and spatial manner within cells. Two calcium-dependent systems may be envisioned to be working in concert to effect physiological change, i.e., via calmodulin (CaM) activation and subsequent regulation of Ca/CaM-dependent protein kinases2,3 and via production of the phosphatidylinositol (PI)-derived messengers inositol trisphosphate (IP3) and diacylglycerol (DG, which activates protein kinase C).4-10 Much of the evidence for the extension of these models to plant systems has come from research on cytokinin-induced cell division and bud formation in target caulonema cells of mosses11-23 and research on cytokinin effects on calcium status of other cytokinin-responsive systems.24
Evaluation of the optimum threshold of gamma-ray for inducing mutation on Polianthes tuberosa cv. double and analysis of genetic variation with RAPD marker
Published in International Journal of Radiation Biology, 2023
Hanifeh Seyed Hajizadeh, Seyed Najmedin Mortazavi, Morteza Ganjinajad, Volkan Okatan, İbrahim Kahramanoğlu
Increasing the radiation dose did not significantly increase this trait in general, so the treatments of 20, 30, and 40 Gy doses of γ-ray did not significantly differ from the control, and only the treatment of 50 Gy showed a significant difference compared to the control and other lower levels of radiation (Table 3). Ling et al. (2008) reported that plants grew more at 10 Gy, while doses above 10 Gy inhibited plant growth, indicating that increased radiation increases the plant’s tolerance to γ-radiation. It may be explained by a decrease in the amount of endogenous plant hormones, especially cytokinin, which results in cytokinin degradation or lack of biosynthesis due to irradiation. It is clear that damage to the cells of tuberose was so serious at the gamma-ray dose of 50 Gy.
Cell homing strategy as a promising approach to the vitality of pulp-dentin complexes in endodontic therapy: focus on potential biomaterials
Published in Expert Opinion on Biological Therapy, 2022
Elaheh Dalir Abdolahinia, Zahra Safari, Sayed Soroush Sadat Kachouei, Ramin Zabeti Jahromi, Nastaran Atashkar, Amirreza Karbalaeihasanesfahani, Mahdieh Alipour, Nastaran Hashemzadeh, Simin Sharifi, Solmaz Maleki Dizaj
Suzuki et al. studied endogenous tooth tissue regeneration by chemotactic cytokines. In their study, dental stem cells were isolated from adult dental pulp and cultured on the surface of three-dimensional collagen cylinders. The chemical medium used different compounds, including stromal-derived factor 1α (SDF1), bFGF, or BMP7. Cellular migration to collagen gel in medium containing bFGF or SDF1 was more significant than in cytokinin-free conditions during 7 days. The results also showed that the effects of BMP7 on the differentiation of dental stem cells into dentin were similar to the impact of dexamethasone but had little effect on cell migration [66]. In one study, hMSCs were exposed to different concentrations of stem cell factor (SCF) to assess cell migration, proliferation, and differentiation into odonto/osteoblasts. First, two immature human premolars were treated with SCF for 6 and 12 weeks in rat calvary. The results showed that in SCF presence, hMSCs migrated, and odonto/osteogenic proliferation and differentiation were detectable [122].
A novel and effective technique to reduce electromagnetic radiation absorption on biotic components at 2.45 GHz
Published in Electromagnetic Biology and Medicine, 2022
Meenu L, Aiswarya S, Sreedevi K. Menon
This experiment is a direct validation and serves as a proof of concept that the EMR exposure rate, time and intensity has an adverse effect on the plant tissues. The study shows that the variation in secretion of plant hormones like Gibberellins, Cytokinins, Abscisic Acid and Auxins had led to the retardation in the complete growth of the plant (Naqvi 1999) – (Arteca 1996.). The radiation is mainly due to the antenna present in the gadgets and these radiations will be absorbed by the vegetation. This is measured in terms of SAR for a given tissue. SAR depends upon dielectric property, conductivity, mass density, electric field strength of the tissues etc. The absorption of radiation by pea seeds near to the router is more as it receives more power in the vicinity of the router. So the variation in absorption results in growth retardation even from its initial stage of the germination. This effect in the sprouting stage makes changes in the entire life cycle of each plant community. These continuous exposure reduces the nutrient capability of vegetations and it makes them unhealthy to human life.