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Heavy Metal Pollution and Medicinal Plants
Published in Azamal Husen, Environmental Pollution and Medicinal Plants, 2022
Allah Ditta, Naseer Ullah, Xiaomin Li, Ghulam Sarwar Soomro, Muhammad Imtiaz, Sajid Mehmood, Amin Ullah Jan, Muhammad Shahid Rizwan, Muhammad Rizwan, Iftikhar Ahmad
HMs absorption in medicinal plants can interact with the accumulation of NPK in the plant body and may result in the deficiency of certain macronutrients. In another experiment conducted by Mishra et al. (2014) it was found that supplementing Cd to the medicinal plant (Withania somnifera) resulted in NPK deficiency along with interruption in growth and development, and necrosis, as well as necrotizing at higher concentrations of Cd. Moreover, photosynthetic pigments’ concentration improved compared to the control (1.75-fold higher than control) at 50 μM and decreased by 0.13-fold at 300 μM. In comparison to the control, total chlorophyll contents (chl a + chl b), chl a and b, and carotenoids declined by 0.1- to 0.2-fold under higher concentrations of Cd, i.e. 200 to 300 μM.
Chemopreventive Agents
Published in David E. Thurston, Ilona Pysz, Chemistry and Pharmacology of Anticancer Drugs, 2021
Although first isolated in an impure form in 1910, the structure of lycopene was not elucidated until approximately 1930. However, due to the complexity of the molecule, particularly in terms of the number of double bonds and their relative configurations, it was not synthesized until 1950. In photosynthetic organisms, including plants, algae, fungi, and photosynthetic bacteria, lycopene is a key intermediate in the biosynthesis of a number of carotenoids, including β-carotene and also the xanthophylls, which play an important role in the red, yellow, or orange photosynthetic pigment-protein complexes, and the processes of photosynthesis and the protection of photosynthetic organisms from excessive light damage. Owing to its strong color, lycopene is used as a food coloring agent known as E160d.
Physical Factors
Published in Michael J. Kennish, Ecology of Estuaries Physical and Chemical Aspects, 2019
Light intensity, quality, and duration (photoperiod) affect the activities and processes of estuarine organisms. Autotrophic production is a function of light intensity. Photosynthesis increases logarithmically with increasing light intensity up to a level of light saturation (Figure 12). At very high light intensities, photosynthesis becomes inhibited because of the bleaching of photosynthetic pigments (e.g., chlorophyll a) or the arresting of pigment production in autotrophs.9 Over extended periods, high light intensities can be lethal to phytoplankton,82 and at low light intensities, photosynthesis declines until the compensation light intensity is reached where photosynthesis just balances respiration. The compensation point occurs at a depth at which light intensity approximates 1% of the surface radiation. The intensity of light at the air-sea surface interface depends on latitude, season, time of day, and weather conditions.
Phytochemical composition, cytotoxicity, antioxidant and antimicrobial responses of Lavandula dentata L. grown under different levels of heavy metals stress condition
Published in Drug and Chemical Toxicology, 2023
Souhila Terfi, Zineb Djerrad, Soumeya Krimat, Fatma Sadi
Photosynthetic pigments (chlorophyll a, b and carotenoid) were determined according to Arnon (1949), with slight modifications. Leaf samples (0.5 g) were homogenized with 8 mL of acetone (80%), filtered and made up to a final volume of 50 mL. The absorbance was measured at 663, 646 and 470 nm using UV spectrophotometer. The photosynthetic pigments contents were calculated using the followed equations (Doğanlar and Atmaca 2011):Chlorophyll a (Chl a): (12.21× A663 – 2.81 × A646) × 50/500 mg of leaf weight,Chlorophyll b (Chl b): (20.13 × A646 – 5.03 × A663) × 50/500 mg of leaf weight,Total chlorophyll (Total Chl): (7.18 × A663 + 17.32 × A646) × 50/500 mg of leaf weight,Carotenoid (Car): [(1000 × A470 − 3.27 × Chl a − 104 × Chl b)/229] × 50/500 mg of leaf weight.
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
Gamma radiation had a significant effect on leaf chlorophyll. The highest amount of chlorophyll was obtained from controls (1.42 mg g−1 FW) followed by 20 Gy (1.10 mg g−1 FW) and 30 Gy (1.23 mg g−1 FW) (Table 3). The effect of 40 and 50 Gy radiation on the chlorophyll parameters of the flowers was significantly different from that of controls. The chlorophyll content decreased with increasing gamma dosage. The results are in agreement with Mohan Jain (2006) and Wi et al. (2007) who demonstrated that chlorophyll pigment decreased with increasing radiation levels. It seems that photosynthetic pigments are degraded by gamma radiation, which reduces photosynthetic capacity and plant germination rate. On the other hand, free radicals are likely generated inside the irradiated organs which caused to cell degradation and metabolisms, such as imbibition of the thylakoid membrane, and changes in photosynthetic and antioxidative ability (Bertolini et al. 2001). Reduction in chlorophyll in buckwheat mutants showed that chlorophyll biosynthesis decreased as the plants were exposed to gamma radiation, which stimulated the activity of chlorophyllase enzyme, increased chlorophyll decay, and finally decreased photosynthetic activity (Moghaddam et al. 2011). Jia and Li (2008) reported that the photosynthesis of pepper plants decreased in response to the increased levels of gamma radiation. However, no definite result has been observed regarding the effect of γ-irradiation on plant chlorophylls.
Mechanism of long-term toxicity of CuO NPs to microalgae
Published in Nanotoxicology, 2018
Xingkai Che, Ruirui Ding, Yuting Li, Zishan Zhang, Huiyuan Gao, Wei Wang
We think that destruction of chloroplast structure by CuO NPs was related to Cu ions released by CuO NPs and Cu2O NPs. On the one hand, a large number of Cu ions released by CuO NPs were absorbed by microalgae (Figure 2(A,B) and Supporting Information Figure S3A) to result in Cu ions toxicity for chloroplast (Figures 4 and 8). On the other hand, however, we find that microalgae could not only absorb Cu ions released by CuO NPs but also could directly enrich CuO NPs which were converted into Cu2O NPs (2–5nm) in the cell concentrated in chloroplast (Figure 6; Supporting Information Figure S6). When microalgae was treated with Cu2+ ions that released the same content of Cu ions as the CuO NPs do into the supernatant, we observed that damage degree of chloroplast caused by Cu2+ was weaker than that caused by CuO NPs (Figures 4 and 8). These results indicate that damage of chloroplast by CuO NPs was not only related to Cu ions toxicity but also might be related to direct damage of chloroplast by CuO NPs and Cu2O NPs. These injuries resulted in chloroplast deformation (Figure 6(B,G)) and degradation of chlorophyll (Figure 7). Further, destruction of chloroplast structure and degradation of photosynthetic pigments disturbed the light conversion and light use efficiency (Figures 8(A,B) and 9(G,H)).