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Khodabande, Z.; Jafarian, V.; Sariri, R.
Chelidonium majus, from Papaveraceae family, is a rich source of different antioxidants with a range of medicinal activities including antispasmodic and diuretic properties. In this study, antioxidant potential of extracts from leaves during different phenological stages was measured by ferric-reducing power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity. Factors affecting antioxidant activity, i.e., total phenols, flavonoids, anthocyanin and carotenoids, were then investigated. Soluble sugar and total protein contents of samples were also determined. According to the results, maximum DPPH radical scavenging activity was 408/88 ± 24/83 g/g DW at growing stage, and the FRAP value reached maximum during fruiting stage (1.75 ± 0.04 mg/g FW). The leaves of flowering stage contained the most content of total phenol (17.8 ± 1.59 mg/g DW), flavonoid (69.7 ± 0.86 mg/g DW), anthocyanin (0.233 ± mg/g DW) and soluble sugar (0.338 ± 0.009 mg/g DW). However, the highest value for carotenoid (2.083 mg/g DW) and protein (0.27 ± 0.034 mg/g DW) was found at the vegetative stage.
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Jun, Kyong Mi; Kim, Joung Sug; Chae, Songhwa; Pahk, Yoon-Mok; Lee, Gang-Seob; Chung, Joon-Hui; Kim, Yeon-Ki; Nahm, Baek Hie
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Rice is one of the most important crops globally and a model plant for genomic studies of monocots. With the release of complete genome sequences, the next challenge is to develop various resources based on functional analyses of genes. In this study, we generated mutants via the insertion of Tos17, a mobile endogenous retrotransposon active during tissue culture. Two rice cultivars, Oryza sativa L. japonica ‘Ilmibyeo’ (IM) and ‘Baegjinju1ho’ (BJJ1), which represent white and brown rice in the Korean domestic market, respectively, were selected for this study. We analyzed 7608 flanking sequences of newly transposed Tos17 insertions by the flanking adaptor-ligation polymerase chain reaction method and identified 1672 and 843 mutants (M2 generation) in IM and BJJ1, respectively. An analysis of these Tos17 insertions showed the preferential insertion of Tos17 into rice chromosome genic regions (approximately 70%). We found new insertional mutants in 830 genes among the 1533 genes representing 2515 IM and BJJ1 mutants that did not overlap with the 3280 genes affected in the ‘Nipponbare’ (NP) mutants from the National Institute of Agrobiological Sciences database. Of the 1000 lines of Tos17 insertion mutants, we observed semi-dwarf and various leaf-type mutants, including those with narrow, pale-green, and striped leaves at the vegetative stage. At the reproductive stage, 10 lines showed a 17–56% increase in 100-grain weight compared with the wild type. This study demonstrates the potential utility of Tos17 mutants via an efficient tissue culture method in various rice cultivars for improving agronomic traits, including seed weight.
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Kim, Dong-Jin; Shin, Hye-Jin; Ahn, Byung-Koo; Lee, Jin-Ho
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This study was conducted to investigate thallium (Tl) adsorption in different soils, including acidic Jeonju (JJ), neutral Iksan (IS), and alkaline Danyang (DY) soils treated with various single counter metal ions and to examine the competitive adsorption of Tl with other metals, including cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn), in multicomponent systems. Thallium buffering capacity of the soils was ordered as IS > DY > JJ soil in the single-component systems, whereas it was DY > IS > JJ soil in the multicomponent systems. In the competitive systems of Tl with different single counter metals, the Tl adsorption capacity of the soils ranged from 20.33 to 88.38 and Tl bonding energy values ranged from 0.369 to 0.731. Thallium adsorption capacity and bonding energy were negatively correlated. Selectivity sequences of metals in multicomponent systems were Pb > Tl > Cu > Ni > Zn > Cd in the JJ soil, Pb > Cu > Tl > Zn > Cd > Ni in the IS soil, and Pb > Cu > Tl ≥ Zn > Cd > Ni in the DY soil. The metal buffering capacity in the JJ, IS, and DY soils varied from 293.2 to 1125.2. The values were ordered as Tl ≫ Pb ≥ Zn ≥ Ni > Cu ≥ Cd in the JJ soil, Pb > Cu > Tl ≫ Ni > Zn ≥ Cd in the IS soil, and Pb > Cu ≫ Tl > Ni > Cd ≥ Zn in the DY soil.
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Ullah, Ihsan; Waqas, Muhammad; Khan, Muhammad Aaqil; Lee, In-Jung; Kim, Won-Chan
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Prolonged water stress adversely affects many aspects of plant physiology, resulting in severe damage to growth and productivity. In response to this and other environmental stresses, plants have evolved complex physiological and biochemical adaptations. To boost existing plant defense mechanisms, this study quantified the negative effects of waterlogging stress and how it may be mitigated by the addition of a natural protective agent. Adzuki beans (Vigna angularis) were grown in commercially available microbe-free soil and subjected to waterlogging stress for 2 weeks. Waterlogging significantly reduced all growth-related variables: shoot length, fresh and dry biomass, chlorophyll content in stressed versus unstressed plants. Waterlogging stress generated reactive oxygen species that heavily damaged plant tissues, causing electrolyte leakage and eliciting an antioxidative response. Specifically, stress-response phytohormone content altered, with a reduction in abscisic acid (ABA) and an increase in jasmonic acid (JA). Furthermore, antioxidants such as malondialdehyde (MDA), catalase (CAT), superoxide dismutase (SOD), polyphenol oxidase (PPO), and peroxidase (POD) were significantly enhanced in waterlogged plants versus non-waterlogged plants. Supplementation of exogenous ascorbic acid (ASC) at 3, 5, and 7 mM revealed that the lowest concentration further reduced ABA and increased JA, enhancing water evaporation rates to raise water-stress tolerance. Moreover, 3 mM ASC also led to lower MDA, CAT, SOD, PPO, POD, and ascorbate peroxidase concentrations in waterlogged plants than in waterlogged plant not treated with ASC. Thus, ASC at a concentration of 3 mM was the most successful in relieving effects of waterlogging stress on plants.
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Lee, Kyoung Bok; Kim, Ye Jin; Kim, Hyo Jin; Choi, Jaehyuk; Kim, Jae Kwang
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Twenty-eight metabolites were extracted from nine Brassicaceae of Korean origin (broccoli, Brussels sprouts, cabbage, Chinese cabbage, kale, kohlrabi, pak choi, radish sprouts, and red cabbage) and analyzed using gas chromatography–mass spectrometry and high-performance liquid chromatography. Principal components analysis (PCA), orthogonal projection to latent structure-discriminant analysis (OPLS-DA), Pearson’s correlation analysis, hierarchical clustering analysis (HCA), and batch learning self-organizing map analysis (BL-SOM) were used to visualize metabolite pattern differences among Brassicaceae samples. The PCA score plots from the metabolic data sets provided a clear distinction between Brassica species and radish sprouts (genus Raphanus L.). Additionally, B. oleracea L. varieties were differentiated from B. rapa L. varieties by PCA and OPLS-DA score plots. HCA and BL-SOM of these metabolites clustered metabolites that are metabolically related. This study demonstrates that plants’ characterization by multivariate statistical analysis using metabolic profiling allows distinguishing their phenotypes and identifying desired characteristics.
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Haroon, Muhammad; Kang, Sun Chul 
In the last few decades, studies on autophagy regulation and its potential role in cancer therapeutics have expanded to include detailed mechanisms. Since apoptosis exhibits drug resistance in some cancers, efforts have focused on searching for compounds with autophagy modulating properties. Numerous natural compounds have been used in cancer treatment and are considered a significant research area due to their remarkable anti-cancer properties. Celastrol, a quinone methide triterpene, derived from Tripterygium wilfordii, has recently drawn much attention because of its anticancer potential. It enhances tumor suppression and induces autophagy in cancer cells by regulating signaling pathways such as Beclin-1, Akt/mTOR, ROS, NF-κB, MAPK, HSP90, and the proteasome. In the current study, we address the anticancer potential of celastrol, its effect on various cellular pathways, and describe how it functions as an autophagy modulator in cancer therapeutics and helps diminish multidrug resistance in cancer cells.
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Lee, Jo-Won; Kim, Bo-Ra; Heo, Yena; Bae, Gui-Seck; Chang, Moon Baek; Moon, BoKyung
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Baechu and radish are the major by-products generated from kimchi factories. Because vegetable and fruit by-products have abundant functional ingredients, the availability of them as a source of bioactive compounds is gaining attention. The objective of this study was to determine the feasibility of using kimchi by-products as sources of functional ingredients. For this purpose, 13 by-product samples were collected from different kimchi factories and analyzed for their sugar contents, total dietary fiber (TDF), antioxidant capacity, water holding capacity (WHC), viscosity, and specific gravity. The dietary fiber contents in kimchi by-product cabbage powder and radish powder were 27.37–49.54 and 30.19–62.81 %, respectively. TDF, WHC, and antioxidant capacities of kimchi by-products were equally as high as those of other by-products that are reused in industry. These results suggested that kimchi by-products have the potential as a new agro-industrial by-product that could be recycled as valuable sources of dietary fibers.
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Kim, Han-bin; Shin, Sooim; Choi, Moonsung 
MauG is a unique c-type diheme oxygenase. One heme of MauG is five-coordinate and solvent accessible with His53 as axial ligand, while the other heme of MauG is six-coordinate with His205 and Tyr294. MauG catalyzes posttranslational modification including oxygen insertion, cross-linkage of two tryptophan and oxidation of quinol to quinone of precursor methylamine dehydrogenase (preMADH) to form mature tryptophan tryptophylquinone (TTQ) which is one of protein-derived cofactors. Long-range remote catalysis of substrate is possible without direct contact between hemes of MauG and its substrate, preMADH. Although catalytic properties and mechanisms of MauG have been well studied, temperature dependence of MauG has never been reported yet. Therefore, the objective of this study was to perform thermodynamic analysis of MauG. ΔH° of 87.6 ± 6.7 kJ mol−1 and ΔS° of 232 ± 15.6 J mol−1 K−1 were directly measured for oxidized MauG in this study. Those results provide fundamental information on controlling electron transfer rates for biosynthesis of TTQ in MADH and are used as a good thermodynamic example study for other diheme systems.
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Andhare, Prasad; Goswami, Dweipayan; Delattre, Cédric; Pierre, Guillaume; Michaud, Philippe; Pathak, Hilor
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Succinoglycan is an industrially important exopolysaccharide (EPS) that is produced by certain bacteria. There are several procedures to extract this EPS, though the efficiency of all the available procedures is questionable and any improvement in the extraction efficient can greatly benefit the industry. Here we emphasize on optimization and development of new modus operandi to efficiently extract succinoglycan from liquid bacterial culture. Also, we studied the effect of different extraction methods on production, rheological and structural properties of succinoglycan. Eighteen different chemical and physical methods were tested for succinoglycan extraction from Rhizobium radiobacter CAS isolates with the principle of extracting EPS by precipitating it, where only eleven methods could precipitate the succinoglycan. Comparing the extraction yield of all methods, biopolymer extracted by acetone (3014 mg/L) was maximum followed by cetyl-trimethyl-ammonium-bromide (CTAB 2939 mg/L) and vacuum evaporation (2804 mg/L) methods. Upon comparison of rheological property of recovered succinoglycan, it was found that at shear rate 50 s−1 EPS recovered using acetone and CTAB methods tends to make the solution highly viscous with a viscosity of 150 and 146 mPa s, respectively. In agreement with these results, power law equation showed that EPS extracted by acetone and CTAB had high consistency index (k) and low flow behavior index (η). The current results showed that the physicochemical methods for EPS extraction significantly affect the structural composition of, though succinoglycan extracted using acetone and CTAB showed minimum structural abrasion.
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By
Han, Sanghyun; Choi, Eun Kyung; Park, Woojun; Yi, Chongku; Chung, Namhyun
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Cracking of concrete over time, is a natural phenomenon. Longer service life of concrete structures is desirable. Self-healing concrete using bacteria, which could form CaCO3 crystals for crack sealing, has promised benefits to reduce cost for concrete maintenance, because cracks could be autonomously repaired without human intervention. However, because of harsh concrete internal environment render the effectiveness depending on the bacteria viability within concrete. In this study, expanded clay (EC) was used as a carrier, to protect bacteria (Lysinibacillus boronitolerans YS11) from the harsh environment during the process. Existence of bacteria inside EC was observed using electron microscopy. When exposed to bacterial solution of 1.0 × 109 cells/mL, bacterial density within EC reached approximately 0.82 × 107 cells/g of dry EC. Extent of bacterial viability within EC, submerged to solution containing 1.0 × 108 cells/mL, was 53.6% of free bacteria solution containing 1.0 × 107 cells/mL, as measured with fluorescein diacetate assay. When rate of calcium carbonate formation was measured with Ca2+ disappearance, rates were comparable between bacteria within EC (submerged to bacterial solution containing 1.0 × 108 cells/mL) and free bacteria (1.0 × 107 cells/mL). This finding indicates that bacteria with EC is very active for generation of CaCO3 within EC. All experimental results suggest that EC may be an adequate bacteria carrier for self-healing concrete.
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