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Utilization of Coal Mine Waste in Vegetation
Published in Karra Ram Chandar, B. C. Gayana, P. Shubhananda Rao, Mine Waste Utilization, 2022
Chaitanya Vikas, Karra Ram Chandar
Potassium regulates the opening and closing of the stomata by a potassium ion pump. Since stomata are important in water regulation, potassium reduces water loss from the leaves and increases drought tolerance. Exchangeable potassium in overburden soil sample is 53.336 meq/100 gm. The predominant role of magnesium is as a major constituent of the chlorophyll molecule, and it is therefore actively involved in photosynthesis. It is a co-factor in several enzymatic reactions that activate the phosphorylation processes and also assists the movement of sugars within a plant.
Structures
Published in Thomas M. Nordlund, Peter M. Hoffmann, Quantitative Understanding of Biosystems, 2019
Thomas M. Nordlund, Peter M. Hoffmann
Chlorophyll molecules are the primary molecular entities responsible for light absorption, electron transfer, and energy conversion in green plants and photosynthetic microorganisms. Like heme, chlorophyll exists in many variants. Chlorophyll a and b are shown in Figure 5.9. The most obvious differences between heme and chlorophyll are (1) a magnesium ion in place of the iron and (2) a long hydrocarbon tail. Some differences less obvious to the physicist reader are (3) the extra 5-carbon ring and (4) the CH3 group in ring. The Fe → Mg replacement suggests the electronic processes governed by chlorophyll will be quite different from those of heme, which is true. The chlorophyll hydrocarbon tail, which you should catalog as a hydrophobic part of the molecule, suggests that chlorophyll should be found near hydrophobic regions. Because water constitutes 70% of the cell mass and is not hydrophobic (of course), chlorophyll should be found either in hydrophobic regions of proteins or in membranes. Both guesses are correct.
Drinking Water Monitoring
Published in Frank R. Spellman, The Drinking Water Handbook, 2017
Water hardness refers primarily to the amount of dissolved calcium and magnesium in the water and their effects on scaling, corrosion, and soap. With hard water, it is difficult to produce a soap lather. Hard waters leave spots on glasses, a film on laundry and hair, and crusty deposits on bathroom fixtures. The presence of hardness in water supplies contributes to taste, odor, color, or turbidity, but water hardness has no health significance (Hauser, 2002). Calcium and magnesium enter water mainly by leaching of rocks. Calcium is the most abundant dissolved cationic constituent of natural freshwaters. Calcium is an important component of aquatic plant cell walls and the shells and bones of many aquatic organisms. Magnesium is an essential nutrient for plants and is a component of the chlorophyll molecule. Hardness test kits express test results in ppm of CaCO3, but these results can be converted directly to calcium or magnesium concentrations:
The enhanced biomass and lipid accumulation in algae with an integrated treatment strategy by waste molasses and Mg2+ addition
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Xunzan Dong, Li Huang, Tao Li, Jun-Wei Xu, Peng Zhao, Xuya Yu
The growth rate and lipid production can be controlled via regulating the availability of essential nutrients and trace metals (Shin et al. 2018). Metal ions, such as iron and magnesium, are very important for cellular mechanisms, including photosynthesis, cell division, respiration, intracellular transportation, and protein synthesis, in microalgae (Singh et al. 2016). As one of the most important trace elements, Mg can serve as the central atom of the chlorophyll molecule in the photosynthetic apparatus, which plays a critical role during photosynthetic activity and is also used to synthesize genetic material. A previous study observed that additional Mg2+ induces microalgae to undergo secondary growth and increases the lipid content, demonstrating that Mg2+ plays an important role in both algal growth and lipid accumulation (Huang et al. 2014). Tran et al. (2010) also confirmed that magnesium sulfate is a major media component affecting the lipid productivity of Botryococcus branuii. Hence, the aim of this study was to assess the effect of Mg2+ addition on algae growth and lipid production using waste molasses-based culture medium, which has not been reported to date to the best of our knowledge.
Effects of intercropping with two Solanum species on the growth and cadmium accumulation of Cyphomandra betacea seedlings
Published in International Journal of Phytoremediation, 2020
Caifang Wu, Yunmin Huan, Liu Yang, Lijin Lin, Ming’an Liao, Jin Wang, Zhihui Wang, Dong Liang, Hui Xia, Yi Tang, Xiulan Lv, Xun Wang
Intercropping with S. alatum and S. diphyllum increased the C. betacea seedling biomass, likely because of the associated enhanced photosynthesis and stress resistance of C. betacea seedlings under Cd stress conditions (Lian et al. 2019). The chlorophyll content directly affects the photosynthetic activities of plants. A previous study proves that interactions between Cd and photosynthetic components can adversely affect the chloroplast ultrastructure and inhibit chlorophyll synthesis (Zhang et al. 2014a). In this study, we observed that intercropping effectively alleviated the Cd-induced inhibition of chlorophyll synthesis in C. betacea seedlings by significantly decreasing the Cd content, ultimately resulting in significantly higher chlorophyll contents in the C. betacea seedlings intercropped with Solanum species than in the monoculture of C. betacea seedlings. Moreover, chlorophyll a is one of the most important photosynthetic pigments. Intercropping increased the chlorophyll a content more than the chlorophyll b content, which can substantially enhance photosynthesis (Hou et al. 2007). Carotenoids have critical protective functions during the assembly and stabilization of the photosynthetic machinery. For example, they protect chlorophyll and membranes (Domonkos et al. 2013). In this study, the carotenoid content in C. betacea seedlings intercropped with Solanum species apparently increased, which could be in response to Cd stress to protect chlorophyll and the photosynthetic machinery from the photooxidative damage (Dias et al. 2013).
Selection of microalgae strains for bicarbonate-based integrated carbon capture and algal production system to produce lipid
Published in International Journal of Green Energy, 2019
Ruo-Lan Zhang, Jing-Han Wang, Long-Yan Cheng, Ya-Jie Tang, Zhan-You Chi
It is not surprising that NaNO3 had a significant effect on both cell growth and lipid accumulation, since nitrogen limitation is a very common method to induce lipid production (Lv et al. 2010). Zn2+ is an essential nutrient, since it is an important element for CA, a metalloenzyme catalyzing the shifting reactions between CO2 and bicarbonate, and this is very important for supplying CO2 to Rubisco to synthesis organic carbon as feedstock for lipid accumulation. Sun and Wang (2009) found that the concentration of Zn2+ at 0.01 mM was essential to keep the optimal growth of I. galbana. However, high Zn2+ concentrations, from 1 to 10 mM, did inhibit the growth of I. galbana. Zn2+ could be toxic at higher concentrations and lead to green algal cell death including Microspora willeana Lagerh., Ulothrixozonata, and Oedogonium sp. (Kebede-Westhead, Pizarro, and Mulbry 2006). Our data suggested that a low concentration of ZnSO4·7H2O favored cell growth and lipid production for N. oleoabundans then its concentration was from 0.002 mM to 0.018 mM. This indicates N. oleoabundans has a lower favorable concentration for Zn2+. Magnesium ions play a crucial role since it is not only the central atom of chlorophyll, but also the cofactor of some key enzyme in the metabolic pathway (Karemore, Pal, and Sen 2013). Wang et al. (2014) indicated reduced chlorophyll concentration caused by magnesium depletion resulted in inhibited growth of Chlorella vulgaris. Our research showed that high levels of MgSO4·7H2O significantly influenced cell growth in a positive manner, from the concentration of 0.3 mM to 1.1 mM (Table S3)s. In addition to Zn2+ and Mg2+, other metal ions (including Ca2+, Fe3+, Cu2+, Co2+) also take part in growth and lipid accumulation of N. oleoabundans in this study, and their impacts on some other microalgal strains reported in previous studies were summarized as well (see Table S5). Metal ions at different concentrations may have various physiological impacts on microalgae, since some of them like Ca2+ are the second messenger (Ren et al. 2014) and others such as Cu2+ and Zn2+ are essential for the activity of different enzymes and play key roles in photosynthetic electron transport (Pinto 2003). Such impacts are strain-dependent as well.