Oxidative stress suppression in C. elegans by peptides from dogfish skin via regulation of transcription factors DAF-16 and HSF-1

Functional peptides were obtained via enzymatic hydrolysis of smooth dogfish (Mustelus canis) skin. The enzyme-assisted process was optimized to achieve high yield of smooth dogfish skin peptides (SDSP). Fractions of...

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Kynurenine Metabolism Lifespan Extension Mediated by Oxidative Stress Response and Hypoxic Response in C. elegans

Innovation in Aging ◽

10.1093/geroni/igab046.2552 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. 684-684

Author(s):

Raul Castro-Portuguez ◽

Jeremy Meyers ◽

Sam Freitas ◽

Hope Dang ◽

Emily Turner ◽

...

Keyword(s):

Oxidative Stress ◽

Transcription Factors ◽

Stress Response ◽

Aging Process ◽

De Novo ◽

Kynurenine Pathway ◽

Oxidative Stress Response ◽

Lifespan Extension ◽

Hypoxic Stress ◽

C Elegans

Abstract Aging is characterized by a progressive decline in the normal physiological functions of an organism, ultimately leading to mortality. Metabolic changes throughout the aging process disrupt the balance and homeostasis of the cell. The kynurenine metabolic pathway is the sole de novo biosynthetic pathway for producing NAD+ from ingested tryptophan. Altered kynurenine pathway activity is associated with both aging and a variety of age-associated diseases, and kynurenine-based interventions can extend lifespan in Caenorhabditis elegans. Our laboratory recently demonstrated knockdown of the kynurenine pathway enzymes kynureninase (KYNU) or 3-hydroxyanthranilic acid dioxygenase (HAAO) increases lifespan by 20-30% in C elegans. However, the mechanism of how these interventions may modulate response against different stressors during the aging process has yet to be explored. Fluorescent reporter strains show the stress-responsive transcription factors skn-1 (ortholog of NRF2/NFE2L2; oxidative stress response) and hif-1 (ortholog of HIF1A; hypoxic stress response) to be highly upregulated when the kynurenine pathway is inhibited. We also demonstrated the increase expression of gst-4 and gcs-1 (transcriptional targets skn-1), which are involved in production of the antioxidant glutathione (GSH), as well as upregulation of cysl-2 (transcriptional target of hif-1), a regulator of cysteine biosynthesis from serine. We hypothesize that lifespan extension resulting from kynurenine pathway inhibition is mediated, at least in part, by upregulation of these transcription factors, providing elevated defense against oxidative stress and hypoxic stress.

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Comprehensive utilization strategy of cellulose in a facile, controllable, high-yield preparation process of cellulose nanocrystals using aqueous tetrabutylphosphonium hydroxide

Green Chemistry ◽

10.1039/d0gc04370b ◽

2021 ◽

Author(s):

Fangchao Cheng ◽

Panpan Zhao ◽

Tulong Ouyang ◽

Jianping Sun ◽

Yiqiang Wu

Keyword(s):

Enzymatic Hydrolysis ◽

Cellulose Nanocrystals ◽

High Yield ◽

Utilization Rate ◽

Preparation Process ◽

Comprehensive Utilization ◽

High Utilization ◽

Hydrolysis Of ◽

Utilization Strategy

Tetrabutylphosphonium hydroxide treatment of cellulose enabled facile, controllable, high-yield preparation of cellulose nanocrystals and effective enzymatic hydrolysis of cellulosic residue, resulting in a high utilization rate of more than 95%.

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Preparation of N-Acetyl-D-Glucosamine by Enzymatic Hydrolysis of Amorphous Chitin

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.160-162.1362 ◽

2010 ◽

Vol 160-162 ◽

pp. 1362-1365 ◽

Cited By ~ 1

Author(s):

Hong Zhu ◽

Qiong Hou

Keyword(s):

Enzymatic Hydrolysis ◽

High Yield ◽

Hydrolysis Of ◽

Amorphous Chitin

Several crude enzymes including cellelase Tv, hemicellulase and lipase, papain as well as cellulase Ac were examined for the effective production of N-acetyl-D-glucosamine (GlcNAc) from amorphous α-chitin. Among the tested crude enzymes, cellulase Tv was found to be the most effective for directly degrading amorphous α-chitin to GlcNAc. High yield of GlcNAc was achieved by choosing the optimum hydrolytic conditions at pH 4.5 and 37°C. By gradually adding, in three tantamount cases, the amount of cellulase Tv to amorphous α-chitin, the yield of GlcNAc reach 55.0%.

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Ultrafast synthesis of isoquercitrin by enzymatic hydrolysis of rutin in a continuous-flow microreactor

Journal of the Serbian Chemical Society ◽

10.2298/jsc150914112w ◽

2015 ◽

Vol 80 (7) ◽

pp. 853-866 ◽

Cited By ~ 9

Author(s):

Jun Wang ◽

Gong An ◽

Shuangshuang Gu ◽

Hongsheng Cui ◽

Xiangyang Wu

Keyword(s):

Enzymatic Hydrolysis ◽

Continuous Flow ◽

Biological Activities ◽

Batch Reactor ◽

Maximum Yield ◽

Enzymatic Reaction ◽

High Yield ◽

Flow Microreactor ◽

Wide Range ◽

Hydrolysis Of

Isoquercitrin is a rare flavonol glycoside with a wide range of biological activities and is a key synthetic intermediate for the production of enzymatically modified isoquercitrin. In order to establish an ultrafast bioprocess for obtaining isoquercitrin, a novel continuous flow biosynthesis of isoquercitrin using the hesperidinase-catalyzed hydrolysis of rutin in a glass-polydimethylsiloxane (PDMS) microreactor was first carried out. Using the developed microchannel reactor (200?m width, 50?m depth, and 2 m length) with one T-shaped inlet and one outlet, the maximum yield of isoquercitrin (98.6%) was achieved in a short time (40 min) under the following optimum conditions: rutin concentration at 1 g L-1, hesperidinase concentration at 0.1 g mL-1, reaction temperature at 40?C, and a flow rate at 2 ?L min-1. The activation energy value Ea of the enzymatic reaction was 4.61 kJ mol-1, and the reaction rate and volumetric productivity were approximately 16.1-fold and 30% higher, respectively, than those in the batch reactor. Thus, the use of a continuous-flow microreactor for the enzymatic hydrolysis of rutin is an efficient and simple approach to achieve a relative high yield of isoquercitrin.

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Effect of Pretreatments on the Enzymatic Hydrolysis of High-Yield Bamboo Chemo-Mechanical Pulp by Changing the Surface Lignin Content

Polymers ◽

10.3390/polym13050787 ◽

2021 ◽

Vol 13 (5) ◽

pp. 787

Author(s):

Lianxin Luo ◽

Xiaojun Yuan ◽

Sheng Zhang ◽

Xuchong Wang ◽

Mingfu Li ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Enzymatic Hydrolysis ◽

Laser Scanning ◽

Lignin Content ◽

Value Added ◽

Laser Scanning Microscopy ◽

High Yield ◽

Confocal Laser ◽

Mechanical Pulp ◽

Hydrolysis Of

Hydrogen peroxide chemo-mechanical pulp (APMP), sulfonated chemo-mechanical pulp (SCMP), and chemical thermomechanical pulp (CTMP) were used as raw materials to explore the effects of hydrogen peroxide (HP), Fenton pretreatment (FP), and ethanol pretreatment (EP) on the enzymatic hydrolysis of high-yield bamboo mechanical pulp (HBMP). The surface lignin distribution and contents of different HBMPs were determined using confocal laser scanning microscopy (CLSM) and X-ray photoelectron spectroscopy (XPS). The correlation between the surface lignin and the enzymatic hydrolysis of HBMP was also investigated. The residue of enzymatic hydrolysis was used to adsorb methylene blue (MB). The results showed that the cracks and fine fibers on the surface of APMP, SCMP, and CTMP increased after FP, when compared to HP and EP. The total removal content of hemicellulose and lignin in SCMP after FP was higher than with HP and EP. Compared to SCMP, the crystallinity increased by 15.4%, and the surface lignin content of Fenton-pretreated SCMP decreased by 11.7%. The enzymatic hydrolysis efficiency of HBMP after FP was higher than with HP and EP. The highest enzymatic hydrolysis of Fenton-pretreated SCMP was 49.5%, which was higher than the enzymatic hydrolysis of Fenton-pretreated APMP and CTMP. The removal rate of MB reached 94.7% after the adsorption of the enzymatic hydrolysis residue of SCMP. This work provides an effective approach for a high value-added utilization of high-yield bamboo pulp.

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