Enzymic glucosylation of phenols

1. A transglucosylase fraction has been obtained from the mycelium of Aspergillus niger. 2. The preparation will transfer α-d-glucopyranosyl residues from maltose and other α-d-glucopyranosides to phenolic and alcoholic hydroxyl groups and to carboxylic acid groups. 3. α-Isomaltosides and α-maltosides are formed when resorcinol and catechol are used as acceptors. 4. pH precipitation and DEAE-cellulose chromatography were used to resolve the activity into two fractions. The properties, in particular polyol inhibition, of one of these fractions have been examined in detail.

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Biogenic Hydroxylated Carboxylate Monomers Serve as Dispersants for Ceramic Particles

MRS Proceedings ◽

10.1557/proc-330-113 ◽

1993 ◽

Vol 330 ◽

Cited By ~ 1

Author(s):

Tao Ren ◽

I. A. Aksay ◽

M. Yasrebi ◽

N. B. Pellerin ◽

J. T. Staley

Keyword(s):

Citric Acid ◽

Carboxylic Acid ◽

Zeta Potential ◽

Carboxylic Acids ◽

Particle Packing ◽

Hydroxyl Groups ◽

Ceramic Particles ◽

Carboxylic Acid Groups ◽

Aqueous Suspensions ◽

Dispersant Adsorption

ABSTRACTA total of 20 biogenic carboxylic acids, which contain one to three negatively charged -COO−group(s), were investigated as dispersion additives in the processing of ceramic particles. Only carboxylic acids containing one or more hydroxyl groups were able to disperse α-A12O3particles in aqueous suspensions. Detailed studies of two carboxylic acids, citric acid and tricarballylic acid were undertaken: measurements of zeta potential, particle packing, and dispersant adsorption characeristics indicated that carboxylic acid groups and hydroxyl groups are both important for dispersion of the ceramic particles. Hydroxyl groups increased the adsorption of the molecules to the particles.

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Grafting TRAIL through Either Amino or Carboxylic Groups onto Maghemite Nanoparticles: Influence on Pro-Apoptotic Efficiency

Nanomaterials ◽

10.3390/nano11020502 ◽

2021 ◽

Vol 11 (2) ◽

pp. 502

Author(s):

Hanene Belkahla ◽

Andrei Alexandru Constantinescu ◽

Tijani Gharbi ◽

Florent Barbault ◽

Alexandre Chevillot-Biraud ◽

...

Keyword(s):

Carboxylic Acid ◽

Cancer Therapy ◽

Computational Study ◽

Carcinoma Cells ◽

Maghemite Nanoparticles ◽

Carboxylic Acid Groups ◽

Lung Carcinoma Cells ◽

Biological Studies ◽

Apoptotic Effect ◽

Carboxylic Groups

Tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) is a member of the TNF cytokine superfamily. TRAIL is able to induce apoptosis through engagement of its death receptors DR4 and DR5 in a wide variety of tumor cells while sparing vital normal cells. This makes it a promising agent for cancer therapy. Here, we present two different ways of covalently grafting TRAIL onto maghemite nanoparticles (NPs): (a) by using carboxylic acid groups of the protein to graft it onto maghemite NPs previously functionalized with amino groups, and (b) by using the amino functions of the protein to graft it onto NPs functionalized with carboxylic acid groups. The two resulting nanovectors, NH-TRAIL@NPs-CO and CO-TRAIL@NPs-NH, were thoroughly characterized. Biological studies performed on human breast and lung carcinoma cells (MDA-MB-231 and H1703 cell lines) established these nanovectors are potential agents for cancer therapy. The pro-apoptotic effect is somewhat greater for CO-TRAIL@NPs-NH than NH-TRAIL@NPs-CO, as evidenced by viability studies and apoptosis analysis. A computational study indicated that regardless of whether TRAIL is attached to NPs through an acid or an amino group, DR4 recognition is not affected in either case.

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Optimization of Ultrasonic-Assisted Extraction, Characterization, and Antioxidant Activities of Polysaccharides From Sojae Semen Praeparatum

Natural Product Communications ◽

10.1177/1934578x211020622 ◽

2021 ◽

Vol 16 (5) ◽

pp. 1934578X2110206

Author(s):

Yongshuai Jing ◽

Ruijuan Zhang ◽

Lan Li ◽

Danshen Zhang ◽

Yu Liu ◽

...

Keyword(s):

Antioxidant Activities ◽

Deae Cellulose ◽

Chemical Compositions ◽

Hydroxyl Groups ◽

Ultrasonic Frequency ◽

Ultrasonic Power ◽

Assisted Extraction ◽

Ultrasonic Time ◽

Ultrasonic Assisted ◽

Ultrasonic Assisted Extraction

In this study, response surface methodology (RSM) was used to optimize the ultrasonic-assisted extraction parameters of Sojae Semen Praeparatum polysaccharides (SSPP-80), the optimum conditions were determined as follows: ultrasonic frequency of 100 W, ultrasonic power of 80 Hz, ultrasonic temperature of 52℃, ultrasonic time of 23 minutes, and liquid to raw material ratio of 40 mL/g. Based on these conditions, polysaccharides extraction rate was 7.72% ± 0.26%. Then, 2 novel polysaccharides (SSPP-80‐1, SSPP-80‐2) were isolated from SSPP by DEAE-cellulose 52 chromatography. The chemical compositions, physicochemical properties, and structure of SSPPs were investigated by simultaneous thermal analyzer (TGA), scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FI-IR), and high-performance liquid chromatography (HPLC). The results showed that SSPP-80 and 2 fractions were mainly composed of mannose (Man), glucose (Glc), galactose (Gal), xylose (Xyl), and arabinose (Ara). In addition, the antioxidant activities were evaluated against the DPPH and hydroxyl radical in vitro, the IC50 of SSPP-80, SSPP-80‐1 and SSPP-80‐2 against DPPH free radical were 4.407, 8.267, and 5.204 mg/mL, respectively, whereas the IC50values for removing hydroxyl groups were 5.318, 3.516, and 4.016 mg/mL, respectively. It demonstrated that SSPP-80 and 2 fractions had certain antioxidant activity. Theoretical basis for use of Sojae Semen Praeparatum polysaccharides was provided by this study.

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Structure-antioxidant activity relationship of methoxy, phenolic hydroxyl, and carboxylic acid groups of phenolic acids

Scientific Reports ◽

10.1038/s41598-020-59451-z ◽

2020 ◽

Vol 10 (1) ◽

Cited By ~ 12

Author(s):

Jinxiang Chen ◽

Jing Yang ◽

Lanlan Ma ◽

Jun Li ◽

Nasir Shahzad ◽

...

Keyword(s):

Antioxidant Activity ◽

Carboxylic Acid ◽

Phenolic Acids ◽

Phenolic Hydroxyl ◽

Activity Relationship ◽

Carboxylic Acid Groups ◽

Relationship Of

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Dual-temperature and pH responsive (ethylene glycol)-based nanogels via structural design

Polymer Chemistry ◽

10.1039/c3py01772a ◽

2014 ◽

Vol 5 (8) ◽

pp. 3061-3070 ◽

Cited By ~ 22

Author(s):

Yohei Kotsuchibashi ◽

Ravin Narain

Keyword(s):

Carboxylic Acid ◽

Ethylene Glycol ◽

Salt Concentration ◽

Structural Design ◽

Solution Temperature ◽

Ph Responsive ◽

Solution Ph ◽

Critical Solution Temperature ◽

Carboxylic Acid Groups ◽

The Core

Dual-temperature and pH responsive (ethylene glycol)-based nanogels were synthesized. Both the core and the shell of the nanogels showed a lower critical solution temperature (LCST) and the LCST of the shell was strongly affected by the solution pH and salt concentration due to the presence of carboxylic acid groups at the nanogel surface.

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