Synthesis of Starch-Graft-Polyacrylamide by Salt Solution Media Polymerization

2012 ◽  
Vol 557-559 ◽  
pp. 1049-1052
Author(s):  
Wen Bing Li ◽  
Ting Ting Huang ◽  
Guang Hua Wang
Keyword(s):  
Salt Solution ◽  
Synthesis Method ◽  
Monomer Conversion ◽  
High Yield ◽  
Solution System ◽  
Raw Starch ◽  
Polymerization System ◽  
Product Loss ◽  
The Difference ◽  
Branched Chain

Starch-graft-polyacrylamide (St-g-PAM) was prepared using a salt media polymerization technique, and characterized by FITR. The type of starch and the synthesis method of different system were studied through the mass of product, the percentage of grafting (PG) and the monomer conversion (MC), and the difference polymerization system. The results showed that the pretreated starch and the salt solution system, respectively, were more advantageous than the raw starch and the aqueous solution system. The intrinsic viscosity, transmittance, product loss, penetration and apparent viscosity of St-g-PAM by salt solution polymerization were 12.49 dL•g-1, 18.6%, 0.56%, 53.96, 18.40 Pa•S, respectively. The method could get bigger branched-chain molecular than the others with high yield, high monomer conversion, high the percentage of grafting, low product losses and easy post-processing

scholarly journals Metabolomic analysis of biosynthesis mechanism of ε-polylysine produced by Streptomyces diastatochromogenes

2020 ◽  
Author(s):  
Ziyuan Wang ◽  
Fengzhu Guo ◽  
Tianyu Dong ◽  
Zhilei Tan ◽  
Mohamed Abdelraof ◽  
...  
Keyword(s):  
Metabolic Regulation ◽  
Absorption Capacity ◽  
High Yield ◽  
Regulation Mechanism ◽  
Original Strain ◽  
Metabolomic Analysis ◽  
Streptomyces Sp ◽  
Activity Of Enzymes ◽  
The Difference ◽  
Branched Chain

Abstract ε-polylysine (ε-PL) is a polypeptide that shows broad-spectrum inhibition against both Gram-positive and Gram-negative bacteria, and it’s mainly produced by Streptomyces sp. However, the biosynthesis mechanism of ε-PL by Streptomyces sp. is still unclear. Herein, the metabolomic analysis of the biosynthesis mechanism of ε-PL in the original strain TUST and the high-yield mutant strain 6#-7 were investigated. Results show that the difference on metabolisms between TUST and 6#-7 was significant during fermentation periods. And based on further analyses of the results of both metabolomics and enzymatic activity, a possible metabolic regulation mechanism of the high-yield mutagenized strain 6#-7 was proposed. The transport and absorption capacity for glucose of strain 6#-7 is improved. And the activity of enzymes relating to ε-PL synthesis, including Hexokinase (HK) et al., is strengthened. On the contrary, the activity of enzymes in the branched-chain pathways, such as Succinate dehydrogenase (SDH) et al. is decreased. Meanwhile, the increase of trehalose, glutamic acid and proline makes the strain 6#-7 more resistant to ε-PL. Moreover, the strain 6#-7 has stronger ability to transfer ε-PL out the cell. Thus the ability of the mutagenized strain to synthesize ε-PL is enhanced and the strain 6#-7 can produce more ε-PL compared with the original strain. These findings provide a theoretical basis for further improving the production of ε-PL.

scholarly journals Metabolomic Analysis of Biosynthesis Mechanism of ε-Polylysine Produced by Streptomyces diastatochromogenes

2021 ◽  
Vol 9 ◽  
Author(s):  
Ziyuan Wang ◽  
Fengzhu Guo ◽  
Tianyu Dong ◽  
Zhilei Tan ◽  
Mohamed Abdelraof ◽  
...  
Keyword(s):  
Metabolic Regulation ◽  
Absorption Capacity ◽  
High Yield ◽  
Regulation Mechanism ◽  
Original Strain ◽  
Metabolomic Analysis ◽  
Homoserine Dehydrogenase ◽  
Yield Strain ◽  
The Difference ◽  
Branched Chain

ε-Polylysine (ε-PL), a natural preservative with broad-spectrum antimicrobial activity, has been widely used as a green food additive, and it is now mainly produced by Streptomyces in industry. In the previous study, strain 6#-7 of high-yield ε-PL was obtained from the original strain TUST by mutagenesis. However, the biosynthesis mechanism of ε-PL in 6#-7 is still unclear. In this study, the metabolomic analyses of the biosynthesis mechanism of ε-PL in both strains are investigated. Results show that the difference in metabolisms between TUST and 6#-7 is significant. Based on the results of both metabolomic and enzymatic activities, a metabolic regulation mechanism of the high-yield strain is revealed. The transport and absorption capacity for glucose of 6#-7 is improved. The enzymatic activity benefits ε-PL synthesis, such as pyruvate kinase and aspartokinase, is strengthened. On the contrary, the activity of homoserine dehydrogenase in the branched-chain pathways is decreased. Meanwhile, the increase of trehalose, glutamic acid, etc. makes 6#-7 more resistant to ε-PL. Thus, the ability of the mutagenized strain 6#-7 to synthesize ε-PL is enhanced, and it can produce more ε-PLs compared with the original strain. For the first time, the metabolomic analysis of the biosynthesis mechanism of ε-PL in the high-yield strain 6#-7 is investigated, and a possible mechanism is then revealed. These findings provide a theoretical basis for further improving the production of ε-PL.

A Simple Synthesis of the Anticancer Drug Altretamine

2020 ◽  
Vol 17 (8) ◽  
pp. 628-630
Author(s):  
Vu Binh Duong ◽  
Pham Van Hien ◽  
Tran Thai Ngoc ◽  
Phan Dinh Chau ◽  
Tran Khac Vu
Keyword(s):  
Aqueous Solution ◽  
Anticancer Drug ◽  
Potassium Hydroxide ◽  
Large Scale ◽  
Synthesis Method ◽  
Practical Method ◽  
Cyanuric Chloride ◽  
Simple Synthesis ◽  
High Yield ◽  
One Step

A simple and practical method for the synthesis on a large scale of altretamine (1), a wellknown antitumor drug, has been successfully developed. The synthesis method involves the conversion of cyanuric chloride (2) into altretamine (1) by dimethylamination of 2 with an aqueous solution of 40% dimethylamine and potassium hydroxide in 1, -dioxan 4in one step to give altretamine (1) in high yield.

scholarly journals Causes Of Yield Gaps And Strategies For Minimizing The Gaps In Different Crops Of Bangladesh

1970 ◽  
Vol 36 (3) ◽  
pp. 469-476 ◽  
Author(s):  
Mohammad H Mondal
Keyword(s):  
New Technologies ◽  
High Yield ◽  
Credit System ◽  
Yield Gap ◽  
Related Factors ◽  
Integrated Crop Management ◽  
Yield Gaps ◽  
The Difference ◽  
The Government ◽  
Extension Agencies

The concept of yield gaps originated from the studies conducted by IRRI in the seventies. The yield gap discussed in this paper is the difference between the potential farm yield and the actual average farm yield. In Bangladesh, yield gaps exist in different crops ranging up to 60%. According to the recent study conducted by BRRI, the yield gap in rice was estimated at 1.74 t/ha. The existence of yield gaps was as well observed in rice, mustard, wheat and cotton in India. In India, yield gap varied from 15.5 to 60% with the national average gap of 52.3% in irrigated ecosystem. The yield gaps are mainly caused by biological, socio-economic, climate and institutional/policy related factors. Different strategies, such as integrated crop management (1CM) practices, timely supply of inputs including credit to farmers, research and extension collaboration to transfer the new technologies have been discussed as strategies to minimize yield gaps. Suggestions have been made to make credit available to resource-poor small farmers to buy necessary inputs. Reducing transaction cost, simplifying lending procedures and strengthening monitoring mechanism of the current credit system are, however, essential to enable the farmers to avail the credit facility. Efforts should be made to update farmers’ knowledge on the causes of yield gaps in crops and measures to narrow the gaps through training, demonstrations, field visits and monitoring by extension agencies to achieve high yield. The government should realize that yield gaps exist in different crops of Bangladesh and therefore, explore the scope to increase production as well as productivity of crops by narrowing the yield gap and thereby ensure food security. Keywords: Yield gaps; strategies; crops of Bangladesh. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9274 BJAR 2011; 36(3): 469-476

scholarly journals Differences in xylem development between Dutch and Japanese tomato (Solanum lycopersicum) correlate with cytokinin levels in hypocotyls

2020 ◽  
Vol 126 (2) ◽  
pp. 315-322 ◽  
Author(s):  
Xiaohua Qi ◽  
Hirokazu Takahashi ◽  
Yasushi Kawasaki ◽  
Yuya Ohta ◽  
Masahide Isozaki ◽  
...  
Keyword(s):  
High Yield ◽  
Growth Stages ◽  
Cytokinin Biosynthesis ◽  
Xylem Development ◽  
Isopentenyl Adenine ◽  
Use Efficiency ◽  
The Difference ◽  
Leaf Photosynthetic Rate ◽  
The Relationship ◽  
Different Growth Stages

Abstract Background and Aims Dutch tomato cultivars tend to have a greater yield than Japanese cultivars even if they are grown under the same conditions. Factors contributing to the increased yield of the Dutch cultivars were a greater light use efficiency and greater leaf photosynthetic rate. On the other hand, the relationship between tomato yields and anatomical traits is still unclear. The aim of this study is to identify the anatomical traits related to the difference in yield between Dutch and Japanese cultivars. Methods Anatomical properties were compared during different growth stages of Dutch and Japanese tomatoes. Hormone profiles and related gene expression in hypocotyls of Dutch and Japanese cultivars were compared in the hypocotyls of 3- and 4-week-old plants. Key results Dutch cultivars have a more developed secondary xylem than Japanese cultivars, which would allow for greater transport of water, mineral nutrients and phytohormones to the shoots. The areas and ratios of the xylem in the hypocotyls of 3- to 6-week-old plants were larger in the Dutch cultivars. In reciprocal grafts of the Japanese and Dutch cultivars, xylem development at the scion and rootstock depended on the scion cultivar, suggesting that some factors in the scion are responsible for the difference in xylem development. The cytokinin content, especially the level of N6-(Δ 2-isopentenyl) adenine (iP)-type cytokinin, was higher in the Dutch cultivars. This result was supported by the greater expression of Sl-IPT3 (a cytokinin biosynthesis gene) and Sl-RR16/17 (a cytokinin-responsive gene) in the Dutch cultivars. Conclusions These results suggest that iP-type cytokinins, which are locally synthesized in the hypocotyl, contribute to xylem development. The greater xylem development in Dutch cultivars might contribute to the high yield of the tomato.

scholarly journals Green Synthesis of Lutein-Based Carbon Dots Applied for Free-Radical Scavenging within Cells

Materials ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4146 ◽  
Author(s):  
Dian Yang ◽  
Li Li ◽  
Lei Cao ◽  
Zhimin Chang ◽  
Qian Mei ◽  
...  
Keyword(s):  
Carbon Dots ◽  
Water Solubility ◽  
Synthesis Method ◽  
Radical Scavenging ◽  
The Body ◽  
Raw Material ◽  
High Yield ◽  
Environmental Friendliness ◽  
Problems In Living ◽  
Living Organisms

Reactive oxygen species (ROS) in the body play an important role in various processes. It is well known that harmful high levels of ROS can cause many problems in living organisms in a variety of ways. One effective way to remove intracellular ROS is to use reducing materials that can enter the cell. Herein, we developed a strong reducing carbon nano-dot from a natural product, lutein, as an initial raw material. This is a hydrothermal synthesis method with the advantages of simplicity, high yield, mild reaction conditions, and environmental friendliness. The prepared carbon dots exhibit bright blue fluorescence, and have good water solubility and biocompatibility. In particular, the carbon dots can easily enter the cell and effectively remove ROS. Therefore, the carbon dots are thought to protect cells from oxidative damage by high levels of ROS.

New Route to Branched-chain Aminodeoxy Sugars by Reaction of Ketoses with Acetonitrile. Synthesis of Methyl 3-C-2′-Aminoethyl-2-deoxy-α-D-arabino-hexopyranoside

1974 ◽  
Vol 52 (1) ◽  
pp. 51-54 ◽  
Author(s):  
Alex Rosenthal ◽  
G. Schöllnhammer
Keyword(s):  
Catalytic Hydrogenation ◽  
Liquid Ammonia ◽  
High Yield ◽  
Lithium Amide ◽  
Branched Chain

Addition of methyl 4,6-O-benzylidene-2-deoxy-α-D-erythro-hexopyranosid-3-ulose (1) to acetonitrile in liquid ammonia at −50 to −60° in the presence of lithium amide gave, in high yield, crystalline methyl 4,6-O-benzylidene-3-C-cyanomethyl-2-deoxy-α-D-arabino-hexopyranoside (2) exclusively. The proof of structure 2 is described. Debenzylidenation of 2 afforded the branched-chain cyano glycoside 3. Compound 3 was converted into its 3,4,6-tri-O-acetate (8) and 4,6-di-O-p-nitrobenzoate (9) derivatives. Catalytic hydrogenation of 3 over rhodium on alumina yielded methyl 3-C-2′-aminoethyl-2-deoxy-α-D-arabino-hexopyranoside which was characterized as its N-2,4-dinitrophenyl derivative (7).

Involvement of Phenolics, Flavonoids, and Phenolic Acids in High Yield Characteristics of Rice (Oryza Sativa L.)

2018 ◽  
Vol 68 ◽  
pp. 19-26 ◽  
Author(s):  
Tran Dang Xuan ◽  
Do Tuan Bach ◽  
Tran Dang Dat
Keyword(s):  
Ferulic Acid ◽  
Chlorogenic Acid ◽  
Caffeic Acid ◽  
Phenolic Acids ◽  
Sinapic Acid ◽  
Development Stage ◽  
Vegetative Stage ◽  
High Yield ◽  
Phenolic Contents ◽  
The Difference

The present study examined the correlation between phenolic acids and flavonoids with high rice yield traits of rice. It was observed that the difference of phenolic contents among the tested rice lines occurred only in the vegetative stage. The concentrations of phenolic acids were higher in the rice high yield cultivars than low yield variety in the vegetative stage, but they either decreased dramatically or disappeared during the development stage. Caffeic acid was found only in high yield rice, whereas chlorogenic acid was detected only in low yield rice. Sinapic acid was the dominant phenolic acid in high yield cultivars at vegetative stage (3.7 mg/g), followed by ferulic acid (1.2 mg/g). These findings suggest that caffeic acid, ferulic acid, sinapic acid and chlorogenic acid may play a particular role in forming yield components in rice. The cultivar B3 contained high amount of sinapic acid may be used as a natural source for pharmaceutical use.

CHARACTERIZATION AND MORPHOLOGY CONTROL OF POLY(p-PHENYLENEDIAMINE) MICROSTRUCTURES IN DIFFERENT pH

NANO ◽  
2011 ◽  
Vol 06 (06) ◽  
pp. 597-601 ◽  
Author(s):  
SI-WEI YANG ◽  
FANG LIAO
Keyword(s):  
Synthesis Method ◽  
Morphology Control ◽  
The Self ◽  
Self Organization ◽  
Controlled Synthesis ◽  
Ph Change ◽  
Solubility In Water ◽  
Product Morphology ◽  
Shape Controlled ◽  
The Difference

A novel and shape-controlled synthesis method for uniformly-shaped poly(p-phenylenediamine) (PpPD) microparticles was developed using ( NH 4)2 S 2 O 8 (APS) as an oxidant. The results demonstrated that the morphologies of PpPD varied from nanofibers to nanospheres and nest-like microspheres by tuning the pH of solution. Tiny pH change leads to the significant change in product morphology. The structure of microspheres is similar to graphene which was first discovered. Further study showed that the PpPD nanofibers were dimer. The difference in the structure of PpPD nanofibers and nanospheres (microspheres) resulted in different solubility in water. The nanosized oligomer crystallites served as starting templates for the nucleation of PpPD nanofibers. Further growth of nanofibers was proceeded by the self-organization of phenazine units or their blocks located at the ends of the PpPD chains.

scholarly journals Branched-chain amino acid oxidation in relation to catabolic enzyme activities in rats given aprotein-free diet at different stages of development

1974 ◽  
Vol 32 (3) ◽  
pp. 615-623 ◽  
Author(s):  
R. D. Sketcher ◽  
W. P. T. James
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Female Rats ◽  
Acid Oxidation ◽  
Stages Of Development ◽  
Oxidation Rates ◽  
Acid Dehydrogenase ◽  
Stage Of Development ◽  
The Difference ◽  
Branched Chain

1. The capacity of animals to conserve branched-chain amino acids was assessed during 3 weeks on a protein-free (PF) diet in groups of female rats at three stages of development, i.e. at weaning (35 g), in a period of rapid growth (85 g) and at maturity (200 g).2. Leucine and valine oxidation was assessed by monitoring the evolution of 14CO2 from a tracer dose of the [1-14C]-labelled L-amino acid given intragastrically. Activities of the L-leucine:2-ketoglutarate aminotransferase (EC 2.6.1.6) and α-keto acid dehydrogenase enzymes in leucine and valine metabolism were also determined in muscle and liver at weekly intervals.3. All three groups of rats given a normal protein intake excreted the same proportion of the dose of labelled leucine and valine. In rats given PF diet there was a consistent reduction in 14CO2 output from both L-[1-14C]leucine and L-[1-14C]valine, but valine was not conserved as efficiently as leucine.4. Muscle dehydrogenase responded to a PF diet in all three groups of rats, but the most marked changes occurred in the youngest group. In addition, there was a decrease in hepatic dehydrogenase activities for leucine and valine catabolism in the weanling group; in older animals there was little change in the α-keto-isovalerate, but a consistent decrease in the activity of the α-keto-isocaproic acid dehydrogenase. The difference in the responsiveness of the dehydrogenases, therefore, matched the difference between leucine and valine oxidation rates in vivo.5. Weanling animals responded rather more efficiently than the older animals to the need to conserve amino acids and there was no evidence of a poorly developed system for adapting to PF intake at this early stage of development.6. Despite reduced catabolism of the amino acids, aminotransferase activities in liver and muscle rose in the first 1–2 weeks on a PF regimen. Aminotransferase activity as such is unlikely to control acid oxidation.

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