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How to Have Outrageously Good Ideas
Published in David S. Sholl, Success and Creativity in Scientific Research, 2021
In the 1840s, a young Louis Pasteur had just finished his doctoral studies. Chemists at that time were fascinated by chemicals that were optically active, meaning that if they were dissolved in a liquid like water the resulting mixture would rotate polarized light that passed through the liquid. Tartaric acid, derived from winemaking, was one such chemical. Pasteur worked with a very similar chemical called paratartaric acid, which was not optically active. He found that if he allowed paratartaric acid to form crystals and looked at them carefully under a microscope, there were two crystal shapes that weren’t quite identical. In fact, the two crystal shapes were mirror images of each other. Pasteur painstakingly separated the two sets of crystals by hand. Dissolving one set of crystals gave a liquid that was optically active, and dissolving the other set of crystals gave a liquid with the opposite optical activity. Pasteur had shown that paratartaric acid was a mixture of two different chemicals whose optical properties somehow exactly balanced each other. This discovery, which was made long before chemists knew that chemicals were made of atoms bonded together to form molecules, ultimately led to the discovery that carbon atoms typically bond to four other atoms.
Mulberry
Published in Debashis Mandal, Ursula Wermund, Lop Phavaphutanon, Regina Cronje, Temperate Fruits, 2021
Malic acid is the primary organic acid found in mulberry fruits, whose content is between 1.132 and 4.467 g/100 g fresh weight and is the highest in M. rubra and the lowest in M. nigra. Other less abundant organic acids include citric acid, tartaric acid, and succinic acid (Gundogdu et al., 2011). However, Özgen et al. (2009) suggested that M. nigra and M. rubra contain more citric acid than malic acid.
Polysaccharides used in Nanoparticle based Drug Delivery Formulations
Published in Akhilesh Vikram Singh, Bang-Jing Li, Polysaccharides in Advanced Drug Delivery, 2020
Sreeranjini Pulakkat, Krishna Radhakrishnan
The dialdehyde homo-bifunctional crosslinker glutaraldehyde was initially the most commonly used crosslinker for preparation of crosslinked polysaccharide nanoparticles[21]. The aldehyde groups of glutaraldehyde react with amine groups present on polysaccharides thereby forming stable covalent crosslinks. Mitra et al. reported the preparation of chitosan nanoparticles by glutaraldehyde crosslinking. They employed a reverse microemulsion technique to restrict the particle size to 100 ± 10 nm. These nanoparticles were capable of carrying the anticancer drug doxorubicin to macrophage tumor cells implanted in Balb/c mice[21]. Gluteraldehyde was later replaced by other crosslinkers such as carbodiimides which allowed the crosslinking reactions to be carried out in mild and aqueous reaction conditions. Carbodiimides are “zero length” crosslinkers which assist the formation of amide linkages by condensation of amino group and carboxylic acid groups. EDC [or EDAC; l-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride], l-cyclohexyl-3-(2-morpholinoethyl) carbodiimide (CMC), dicyclohexyl carbodiimide (DCC) are some of the carbodiimides used in polysaccharide crosslinking. Recently natural di- or tri carboxylic acids such as, malic acid, tartaric acid, succinic acid and citric acid have been used as biocompatible chemical crosslinkers[22].
Rhizobacteria Enhancing Accumulation of Copper in Contaminated-soil by Ricinus communis L
Published in Soil and Sediment Contamination: An International Journal, 2022
Castor plants with consistent growth were selected. The castor roots were washed with tap water to remove soil attached to the roots, then immersed and washed in ultrapure water for 3 to 5 times, and stood in ultrapure water for 24 hours. A small amount of thymol was added to prevent microbial degradation. The materials were treated in three replicates. The collected root exudates were loaded into an anion exchange column (Dowexl×8, 100–200 mesh, Shanghai Anland), and eluted with 1 mol/L HCl. The eluate was concentrated by rotary evaporation at 45°C, dissolved with 2 ml of ultrapure water, and measured for the composition and content of organic acids by HPLC (Agilent 1260,America). The chromatographic conditions were as follows: chromatographic column (ZORBAX Eclipse Plus C18, 4.6 × 150 mm), mobile phase (0.01 mol/L K2HPO4, pH2.2), flow rate 0.3 ml/min, column temperature 25°C, injection volume 5 μl, and UV detection wavelength 210 nm. Such eight organic acids as oxalic acid, tartaric acid, malic acid, malonic acid, lactic acid, acetic acid, citric acid and succinic acid were used as standard samples.
Microwave-assisted recovery of lead from electrolytic manganese anode sludge using tartaric acid and NaOH
Published in Environmental Technology, 2023
Rong Zhu, Hailin Long, Yongmi Wang, Huimin Xie, Shaohua Yin, Shiwei Li
It can be seen that tartaric acid is a dibasic hydroxy carboxylic acid, which contains two dissociable carboxyl groups. The oxygen atoms in the carboxyl group and the hydroxyl group can provide abundant electron pairs. There are vacant d orbitals outside the transition metal cation nucleus (such as Cu2+, Fe3+, Pb2+, etc.) [42]. Therefore, they can produce strong coordination between them, forming many coordination bonds to form stable complexes. Tartaric acid has stronger coordination ability with metal ions than ordinary carboxylic acids. It contains two carboxyl groups and hydroxyl groups that can provide more coordination atoms, and can form very stable chelate-shaped coordination compounds with metal ions [43].
Under-utilized wild fruit Lepisanthes rubiginosa (Roxb.) Leenh: A discovery of novel lycopene and anthocyanin source and bioactive compound profile changes associated with drying conditions
Published in Drying Technology, 2023
Theeraphan Chumroenphat, Apichaya Bunyatratchata, Sirithon Siriamornpun
The contents of 7 organic acids in LRL including oxalic acid, citric acid, tartaric acid, malic acid, quinic acid, succinic acid, and fumaric acid are shown in Table 3. The organic acids were identified based on their retention time and their content was quantified by the peak area from HPLC analysis. The results demonstrated that total organic acids content was mostly in the following order: fresh > FD > SD > HD. The individual organic acids differed according to the drying method. Generally, FD showed the highest level for each organic acid, followed by SD and HD, respectively. However, in the case of tartaric acid and malic acid, SD displayed the highest contents, followed by FD and HD, respectively (Table 3).