scholarly journals Optimization of 3', 4'-Anhydrovinblastine Synthesis in vitro Using Crude Extracts of Catharanthus roseus Irradiated with Near-Ultraviolet Light

2016 ◽  
Vol 11 (8) ◽  
pp. 1934578X1601100
Author(s):  
Mamiko Asano ◽  
Kazuo Harada ◽  
Akiko Umeno ◽  
Kazumasa Hirata
Keyword(s):  
Ultraviolet Light ◽  
Catharanthus Roseus ◽  
Large Scale ◽  
Enzymatic Reaction ◽  
Coupling Reaction ◽  
Production Costs ◽  
High Yield ◽  
Flavin Mononucleotide ◽  
Near Ultraviolet ◽  
Crude Extracts

Dimeric indole alkaloids (DIAs), such as vinblastine and vincristine, found in Catharanthus roseus are used clinically as antitumor drugs. A stable supply of DIAs is desired because these alkaloids are very expensive due to their low abundance in plants. A coupling reaction between catharanthine (CAT) and vindoline (VID) is the rate-limiting step of DIAs biosynthesis in planta. 3', 4'-Anhydrovinblastine (AVLB), the product of the coupling reaction, is the precursor of CAT and VID. Therefore, an effective AVLB production system is greatly required. Previously we found that the coupling reaction of CAT and VID to produce AVLB occurred in the presence of flavin mononucleotide and manganese ion (II) by irradiation with near-ultraviolet light at a peak of 370 nm without the presence of any enzyme. In this study, we investigated the effects of organic solvents on this non-enzymatic reaction. We show that the addition of 10% methanol to the reaction mixture permitted the preparation of a highly concentrated substrate solution, resulting in a high yield of AVLB by the coupling reaction. Conditions for the coupling reaction in 10% methanol solution were optimized. We also confirmed that the coupling reaction could occur in crude extracts of C. roseus obtained by organic solvent extraction. These findings suggest a method to produce DIAs on a large scale with reduced production costs.

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 Metal-free oxidative cross-coupling enabled practical synthesis of atropisomeric QUINOL and its derivatives

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Peng-Ying Jiang ◽  
Kai-Fang Fan ◽  
Shaoyu Li ◽  
Shao-Hua Xiang ◽  
Bin Tan
Keyword(s):  
Asymmetric Catalysis ◽  
Kinetic Resolution ◽  
Academic Research ◽  
Coupling Reaction ◽  
Cross Coupling ◽  
Industrial Applications ◽  
Lewis Base ◽  
Production Costs ◽  
Metal Free ◽  
Base Catalysts

AbstractAs an important platform molecule, atropisomeric QUINOL plays a crucial role in the development of chiral ligands and catalysts in asymmetric catalysis. However, efficient approaches towards QUINOL remain scarce, and the resulting high production costs greatly impede the related academic research as well as downstream industrial applications. Here we report a direct oxidative cross-coupling reaction between isoquinolines and 2-naphthols, providing a straightforward and scalable route to acquire the privileged QUINOL scaffolds in a metal-free manner. Moreover, a NHC-catalyzed kinetic resolution of QUINOL N-oxides with high selectivity factor is established to access two types of promising axially chiral Lewis base catalysts in optically pure forms. The utility of this methodology is further illustrated by facile transformations of the products into QUINAP, an iconic ligand in asymmetric catalysis.

A novel near-ultraviolet-light excitable Eu3+-doped Sr2LaTaO6 red phosphor for white-light-emitting diodes

Optik ◽  
2021 ◽  
Vol 240 ◽  
pp. 166908
Author(s):  
Qifeng Tang ◽  
Tao Yang ◽  
Haifeng Huang ◽  
Jinqing Ao ◽  
Biyou Peng ◽  
...  
Keyword(s):  
Ultraviolet Light ◽  
White Light ◽  
Light Emitting Diodes ◽  
Red Phosphor ◽  
Light Emitting ◽  
Near Ultraviolet ◽  
White Light Emitting Diodes

Nerve autofluorescence in near-ultraviolet light markedly enhances nerve visualization in vivo

2021 ◽  
Author(s):  
Fernando Dip ◽  
Pedro Bregoli ◽  
Jorge Falco ◽  
Kevin P. White ◽  
Raúl J. Rosenthal
Keyword(s):  
Ultraviolet Light ◽  
Near Ultraviolet

scholarly journals Generation of 280 THz-spanning near-ultraviolet light in lithium niobate-on-insulator waveguides with sub-100 pJ pulses

APL Photonics ◽  
2020 ◽  
Vol 5 (12) ◽  
pp. 121301
Author(s):  
Marc Reig Escalé ◽  
Fabian Kaufmann ◽  
Hehai Jiang ◽  
David Pohl ◽  
Rachel Grange
Keyword(s):  
Lithium Niobate ◽  
Ultraviolet Light ◽  
Near Ultraviolet

scholarly journals Extraction of short chain chitooligosaccharides from fungal biomass and their use as promoters of arbuscular mycorrhizal symbiosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Andrea Crosino ◽  
Elisa Moscato ◽  
Marco Blangetti ◽  
Gennaro Carotenuto ◽  
Federica Spina ◽  
...  
Keyword(s):  
Fungal Biomass ◽  
Large Scale ◽  
Low Cost ◽  
Trichoderma Viride ◽  
Arbuscular Mycorrhizal ◽  
Am Fungi ◽  
Production Costs ◽  
Short Chain ◽  
Mycorrhizal Symbiosis ◽  
Major Interest

AbstractShort chain chitooligosaccharides (COs) are chitin derivative molecules involved in plant-fungus signaling during arbuscular mycorrhizal (AM) interactions. In host plants, COs activate a symbiotic signalling pathway that regulates AM-related gene expression. Furthermore, exogenous CO application was shown to promote AM establishment, with a major interest for agricultural applications of AM fungi as biofertilizers. Currently, the main source of commercial COs is from the shrimp processing industry, but purification costs and environmental concerns limit the convenience of this approach. In an attempt to find a low cost and low impact alternative, this work aimed to isolate, characterize and test the bioactivity of COs from selected strains of phylogenetically distant filamentous fungi: Pleurotus ostreatus, Cunninghamella bertholletiae and Trichoderma viride. Our optimized protocol successfully isolated short chain COs from lyophilized fungal biomass. Fungal COs were more acetylated and displayed a higher biological activity compared to shrimp-derived COs, a feature that—alongside low production costs—opens promising perspectives for the large scale use of COs in agriculture.

scholarly journals Tyrosinase Nanoparticles: Understanding the Melanogenesis Pathway by Isolating the Products of Tyrosinase Enzymatic Reaction

2021 ◽  
Vol 22 (2) ◽  
pp. 734
Author(s):  
Paul K. Varghese ◽  
Mones Abu-Asab ◽  
Emilios K. Dimitriadis ◽  
Monika B. Dolinska ◽  
George P. Morcos ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Large Scale ◽  
Magnetic Beads ◽  
Enzymatic Reaction ◽  
Oculocutaneous Albinism ◽  
Transmission Electron ◽  
Hill Kinetics ◽  
Rate Limiting ◽  
Human Tyrosinase

Human Tyrosinase (Tyr) is the rate-limiting enzyme of the melanogenesis pathway. Tyr catalyzes the oxidation of the substrate L-DOPA into dopachrome and melanin. Currently, the characterization of dopachrome-related products is difficult due to the absence of a simple way to partition dopachrome from protein fraction. Here, we immobilize catalytically pure recombinant human Tyr domain (residues 19–469) containing 6xHis tag to Ni-loaded magnetic beads (MB). Transmission electron microscopy revealed Tyr-MB were within limits of 168.2 ± 24.4 nm while the dark-brown melanin images showed single and polymerized melanin with a diameter of 121.4 ± 18.1 nm. Using Hill kinetics, we show that Tyr-MB has a catalytic activity similar to that of intact Tyr. The diphenol oxidase reactions of L-DOPA show an increase of dopachrome formation with the number of MB and with temperature. At 50 °C, Tyr-MB shows some residual catalytic activity suggesting that the immobilized Tyr has increased protein stability. In contrast, under 37 °C, the dopachrome product, which is isolated from Tyr-MB particles, shows that dopachrome has an orange-brown color that is different from the color of the mixture of L-DOPA, Tyr, and dopachrome. In the future, Tyr-MB could be used for large-scale productions of dopachrome and melanin-related products and finding a treatment for oculocutaneous albinism-inherited diseases.

scholarly journals Additive-Enhanced Exfoliation for High-Yield 2D Materials Production

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 601
Author(s):  
Dinh-Tuan Nguyen ◽  
Hsiang-An Ting ◽  
Yen-Hsun Su ◽  
Mario Hofmann ◽  
Ya-Ping Hsieh
Keyword(s):  
Large Scale ◽  
2D Materials ◽  
Transition Metal Dichalcogenides ◽  
Spectroscopic Characterization ◽  
High Yield ◽  
Nanometer Scale ◽  
Efficient Production ◽  
Device Performance ◽  
Metal Dichalcogenides ◽  
Scale Deposition

The success of van-der-Waals electronics, which combine large-scale-deposition capabilities with high device performance, relies on the efficient production of suitable 2D materials. Shear exfoliation of 2D materials’ flakes from bulk sources can generate 2D materials with low amounts of defects, but the production yield has been limited below industry requirements. Here, we introduce additive-assisted exfoliation (AAE) as an approach to significantly increase the efficiency of shear exfoliation and produce an exfoliation yield of 30%. By introducing micrometer-sized particles that do not exfoliate, the gap between rotor and stator was dynamically reduced to increase the achievable shear rate. This enhancement was applied to WS2 and MoS2 production, which represent two of the most promising 2D transition-metal dichalcogenides. Spectroscopic characterization and cascade centrifugation reveal a consistent and significant increase in 2D material concentrations across all thickness ranges. Thus, the produced WS2 films exhibit high thickness uniformity in the nanometer-scale and can open up new routes for 2D materials production towards future applications.

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