scholarly journals Crosslinking Efficacy and Cytotoxicity of Genipin and Its Activated Form Prepared by Warming It in a Phosphate Buffer: A Comparative Study

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6600
Author(s):  
Takeya Kawamura ◽  
Shunji Yunoki ◽  
Yoshimi Ohyabu ◽  
Toshio Uraoka ◽  
Kazuaki Muramatsu
Keyword(s):  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Mechanical Tests ◽  
Buffer Solution ◽  
Sodium Phosphate Buffer ◽  
In Situ Forming ◽  
Custom Made ◽  
Acute Cytotoxicity ◽  
Sodium Phosphate Buffer Solution

The aim of the present study was to compare the acute and cumulative cytotoxicity of intact (n-GE) and warmed genipin (w-GE), while investigating the differences in crosslinking capabilities of these two genipins by rheological and mechanical tests. The n-GE solution was prepared by dissolving genipin powder in a sodium phosphate buffer solution. The w-GE solution was prepared by warming the n-GE solution at 37 °C for 24 h. The mechanical tests for chitosan (CH)/genipin gels showed the crosslinking rate of w-GE was much greater than that of n-GE up until 6 h after preparation, whereas the degree of crosslinking of CH/n-GE gels became higher at 12 h. The ISO 10993-5 standard method, which is established specifically for evaluating cumulative cytotoxicity, determined equivalent IC50 for w-GE (0.173 mM) and n-GE (0.166 mM). On the other hand, custom-made cytotoxicity tests using a WST-8 assay after 1 h of cultivation showed that the acute cytotoxicity of w-GE was significantly higher than that of n-GE at concentrations between 0.1–5 mM. The acute cytotoxicity of w-GE should be taken into consideration in its practical uses, despite the fact that the much faster crosslinking of w-GE is useful as an effective cross linker for in-situ forming gels.

scholarly journals Investigation of guanidine hydrochloride induced unfolding of apolipoprotein A-IMilano

2002 ◽  
Vol 16 (3-4) ◽  
pp. 199-206 ◽  
Author(s):  
Malin Suurkuusk ◽  
Dan Hallén
Keyword(s):  
Phosphate Buffer ◽  
Sodium Phosphate ◽  
Guanidine Hydrochloride ◽  
Phosphate Buffer Solution ◽  
Buffer Solution ◽  
Unfolded Protein ◽  
Sodium Phosphate Buffer ◽  
Apolipoprotein A ◽  
Helical Content ◽  
Sodium Phosphate Buffer Solution

A guanidine hydrochloride (GuHCl) induced unfolding study of apolipoprotein A-IMilano(apo A-IM) has been performed. The unfolding was followed by circular dichroism (CD) measurements at 222 nm and by isothermal titration (ITC) calorimetry at 25°C. In the ITC experiments enthalpies of transfer were determined for apo A-IMfrom aqueous sodium phosphate buffer solution into solutions of different concentrations of GuHCl. The CD data and the ITC data give complementary and consistent results of the complex unfolding process. Analytical ultracentrifugation experiments were made on apo A-IMin sodium phosphate buffer and in 0.6 M GuHCl, respectively. Analyses of the obtained sedimentation velocity data show that apo A-IMis highly aggregated in sodium phosphate buffer. The aggregates are almost completely dissociated in 0.6 M GuHCl. Aggregation of the protein in sodium phosphate buffer solution induces an increase in α-helical content. The loss of α-helical secondary structural element of the protein upon dissociation of the aggregates destabilises the protein resulting in a low GuHCl concentration of unfolding, [GuHCl]m=1.1 M. The unfolded protein has a significant α-helical content at the unfolded state. From ITC- and CD data we suggest that increased binding of GuHCl to the unfolded protein results in a disruption of the residual secondary structure.

Ibuprofen removal from aqueous solution by in situ electrochemically generated ferrate(VI): proof-of-principle

2015 ◽  
Vol 73 (2) ◽  
pp. 389-395 ◽  
Author(s):  
Ljiljana Nikolić-Bujanović ◽  
Milan Čekerevac ◽  
Milena Tomić ◽  
Mladen Zdravković
Keyword(s):  
Aqueous Solution ◽  
Organic Carbon ◽  
Aqueous Solutions ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Oxygen Demand ◽  
Buffer Solution ◽  
Effective Removal ◽  
Proof Of Principle

The possibility of removing pharmaceuticals from aqueous solutions was examined using ibuprofen (Ibu) oxidation as an example, using in situ electrochemically synthesized ferrate(VI), a strong oxidant and coagulant, with forming of non-harmful byproducts. A solution of ibuprofen of 206 mg/L in 0.1 M phosphate buffer solution was treated with different amounts of fresh, electrochemically synthesized ferrate(VI). The changes of ibuprofen concentration in samples were determined using a UV-Vis spectrophotometer. The extent of mineralization was estimated using the changes in chemical oxygen demand (COD) values and total organic carbon (TOC) values of test samples. The largest reduction of the concentration of Ibu (41.75%) was obtained by adding 69.2 mg/L ferrate(VI) as Fe (Ibu: Fe = 1: 0.34). An effective removal of ibuprofen from aqueous solutions was recorded up to 68% and it can be done by using ferrate(VI) in the ratio Ibu: Fe = 1:3 as Fe. The possibility of ibuprofen removal by ferrate(VI) was confirmed by COD and TOC results, which demonstrated reduction up to 65% and 63.6%, respectively.

scholarly journals Effect of combination of electrolyte and buffer on electrical production in fuel cell microbial system with Pseudomonas sp. in molasses substrate

2020 ◽  
Vol 211 ◽  
pp. 03001
Author(s):  
Maswati Baharuddin ◽  
Muh Rajib ◽  
Sappewali ◽  
Ummi Zahra
Keyword(s):  
Electrolyte Solution ◽  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Potassium Phosphate ◽  
Salt Bridge ◽  
High Energy ◽  
Pseudomonas Sp ◽  
Buffer Solution ◽  
Sodium Phosphate Buffer ◽  
Potassium Phosphate Buffer Solution

MFC is a bio-electrochemical system driving an electric current by using high-energy bacteria and oxidants. This research aimed to investigate the effect of electrolyte and buffer on electrical production using Pseudomonas sp. In Molasses substrate. The method in this research was the double compartment that consist of anode and cathode chambers. Both were related by salt bridge. This study showed that the addition of a combination of KMnO4 electrolyte solution with sodium phosphate buffer solution obtained a maximum potential difference of 0.67 V. The result also revealed that the combination of KMnO4 electrolyte solution with Potassium Phosphate Buffer solution produced a 1.44 mA maximum current with power density of 660.82 mW/m2.

In-Situ Observation of Nanowire Growth from Luminescent CdTe Nanocrystals in a Phosphate Buffer Solution

ChemPhysChem ◽  
2004 ◽  
Vol 5 (10) ◽  
pp. 1600-1602 ◽  
Author(s):  
Yuri Volkov ◽  
Siobhan Mitchell ◽  
Nikolai Gaponik ◽  
Yurii P. Rakovich ◽  
John F. Donegan ◽  
...  
Keyword(s):  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Nanowire Growth ◽  
In Situ Observation ◽  
Buffer Solution ◽  
Cdte Nanocrystals

Mussel-inspired in situ forming adhesive hydrogels with anti-microbial and hemostatic capacities for wound healing

2018 ◽  
Vol 33 (7) ◽  
pp. 915-923 ◽  
Author(s):  
Xiaoman Han ◽  
Guihua Meng ◽  
Qian Wang ◽  
Lin Cui ◽  
Hao Wang ◽  
...  
Keyword(s):  
Glutamic Acid ◽  
Phosphate Buffer Solution ◽  
Wound Dressings ◽  
Buffer Solution ◽  
Adhesion Properties ◽  
H Nmr ◽  
Chemical Structures ◽  
In Situ Forming ◽  
Ft Ir

All kinds of commercially available wound dressings are clinically used as fleshly obstacles and therapeutic materials in opposition to microbial incursion. Few researches focused on effective-bleeding and anti-bacteria at the same time. In order to better solve this problem, two hydrogels were synthetized in this study. One is phosphate buffer solution-activated dopamine-modified-γ-poly glutamic acid (PBS-PD) hydrogel, the other one is cirsium setosum extracts-activated dopamine-modified-γ-poly glutamic acid (CSE-PD) hydrogel. The two hydrogels are prepared by applying an enzyme-catalyzed crosslinking means in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H2O2). The chemical structures were characterized through 1H-NMR and FT-IR. In conclusion, both PBS-PD and CSE-PD hydrogels exhibit superior tissue adhesion properties, and remarkable anti-infection quality. In addition, these two hydrogels manifest prominent hemostatic efficiency. The bio adhesion performance can achieve 30 kPa, meanwhile the CSE-PD hydrogels show good germicidal properties, and the antibacterial rate can reach 98%. The hydrogels could reduce blood loss without any obvious side effect, and present a new prospect in the field of hemostasis rapidly.

scholarly journals Extracting Sweetening and Bioactive Compounds From Stevia Rebaudiana Using Cellulase Enzyme

2021 ◽  
Vol 910 (1) ◽  
pp. 012022
Author(s):  
Dhia F. Al-Fekaiki ◽  
Basair A. Al-Temimi
Keyword(s):  
Bioactive Compounds ◽  
Phosphate Buffer Solution ◽  
Stevia Rebaudiana ◽  
Steviol Glycosides ◽  
Enzyme Extract ◽  
Buffer Solution ◽  
Solution Ph ◽  
E Coli ◽  
Sodium Phosphate Buffer ◽  
Sodium Phosphate Buffer Solution

Abstract This study was conducted to find out the sweetener and bioactive compounds in the Stevia plant’s enzyme extract and its antioxidant and antibacterial effect. The enzyme extract was used in a ratio of 1:15 (w: v) with the use of sodium phosphate buffer solution (pH=4) in an equal mixing ratio with the enzyme. Extraction was carried out at 55°C with a time of 25 minutes to extract and determine steviol glycosides using HPLC. Stevioside and Rebaudioside-A (5.101 and 3.027 mg/g) were obtained, respectively. The study showed that Stevia contains high amounts of phenols and flavonoids (83.052 and 71,765) mg/ml, respectively. The enzyme extract gave an antioxidant activity of 71.367% compared to BHT which gave an activity of 77.267%. It gave the highest inhibitory activity against Bacillus subtilis, which was 14 mm, followed by Staphylococcus aureus and E. coli. The bioactive compounds were diagnosed by GC-MS and contained important bioactive compounds such as Hydroxydehydrostevic acid (steviol), 1,2-Benzenediol, 4-Ethylcatechol, 9-Octadecenamide, (Z)-, Isosteviol methyl ester, gamma-Sitosterol.

scholarly journals Cover Picture: In-Situ Observation of Nanowire Growth from Luminescent CdTe Nanocrystals in a Phosphate Buffer Solution (ChemPhysChem 10/2004)

ChemPhysChem ◽  
2004 ◽  
Vol 5 (10) ◽  
pp. 1457-1457
Author(s):  
Yuri Volkov ◽  
Siobhan Mitchell ◽  
Nikolai Gaponik ◽  
Yurii P. Rakovich ◽  
John F. Donegan ◽  
...  
Keyword(s):  
Phosphate Buffer ◽  
Phosphate Buffer Solution ◽  
Nanowire Growth ◽  
In Situ Observation ◽  
Buffer Solution ◽  
Cdte Nanocrystals
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