Rare cases of colonic schwannomas.

Schwannomas of the gastrointestinal tract are rare spindle cell tumors that account for 2-6% of mesenchymal tumors. An elderly male was found to have a left colon mass on CT scan and colonoscopy with pathology of fibrotic tissue. A laparoscopic-assisted left hemi-colectomy with primary anastomosis was performed. Pathology demonstrated spindle cell neoplasm arranged in short fascicles that were strongly and diffusely positive for S100. An elderly female was found to have a submucosal lesion on surveillance colonoscopy in the proximal transverse colon. Biopsy with jumbo forceps revealed spindle cell neoplasm positive for S100. Patient underwent an uncomplicated limited non-oncologic segmental transverse colectomy. We report only the ninth case of left and sixth in the transverse colon described in the literature. As is true for other mesenchymal tumors, mucosal biopsy is usually inconclusive and deep biopsy or submucosal resection is required, making pre-operative surgical decision difficult.

Effects of the Extraction Solvents on Dissolution Rate and Antioxidant Capacity of Auricularia auricula (Agaricomycetes) Polysaccharides In Vitro and In Vivo.

This paper reports the effects of solvents on the dissolution rate and antioxidant capacity of Auricularia auricula polysaccharides (AAPs). The ultra-low temperature combined with microwave extraction (UME) was used to compare the dissolution rates and molecular weights of AAPs using deionized water and deep eutectic solvents (DES) as solvents, respectively. Scanning electron microscope (SEM) was used to observe the effects of water extract (AAPs-FW) and DES extract (AAPs-FD) on the cell wall of A. auricula. The antioxidant capacity of polysaccharide extracts in vitro was assessed by using various methods (DPPH, ABTS, and hydroxyl radicals). In addition, in vivo oxidative stress was assessed using Caenorhabditis elegans models. The extract yield of AAPs varied among the extracts and was 19.58% ± 0.56% in AAPs-FW. Whereas DES-UME increased the yield of polysaccharides (AAPs-FD) by 9.81% in the extraction medium containing triethylene glycol-choline chloride, under the optimum conditions of 60 min freezing time, 350 W, and 90 s microwave time. The microstructure of the cell wall shown by SEM was consistent with the results of polysaccharide yields. The molecular weights of AAPs-FW and AAPs-FD were found to be 398.107 kDa and 89.099 kDa, respectively. The results demonstrated that AAPs-FD exhibited potent radical scavenging activity against DPPH and a weaker scavenging ability for ABTS and OH radicals compared to AAPs-FW. In addition, both polysaccharide extracts increased the survival rate of C. elegans under methyl viologen induced oxidative stress at specific concentrations (p < 0.05), and the antioxidant capacity of AAPs-FD was higher than that of AAPs-FW at low concentrations (0.125 mg/mL). This indicated that both polysaccharides had a protective effect against damage induced by intracellular free radical generators (methyl viologen).

Preparation of Auricularia auricula polysaccharides and their protective effect on acute oxidative stress injury of Caenorhabditis elegans.

This research enhanced the extraction procedure for Auricularia auricula crude polysaccharides by utilizing a modified Fenton reagent as a solvent, and obtained A. auricula polysaccharides (AAPs-VH) via alcohol precipitation and deproteinization. The HPLC profile revealed that the purified AAPs-VH using Sepharose 6FF was mainly a heteropolysaccharide, consisting primarily of mannose, glucuronic acid, glucose, and xylose. The Mw and Mn of the purified AAPs-VH were 87.646 kDa and 48.854 kDa, respectively. The FT-IR and NMR spectra revealed that the purified AAPs-VH belonged to pyranose and were mainly formed by (1 â†’ 3)-linked-ß-D glucan formation. In vivo experiments conducted with Caenorhabditis elegans, AAPs-VH was found to notably influence the lifespan, improve the antioxidant system, and decrease the level of cell apoptosis. This might be achieved by up-regulating the expression of genes in the IIS and TOR pathways. The study concludes that the modified Fenton reagent can increase Auricularia auricula polysaccharide solubleness and active sites, which may be an essential prompt for future studies.

Comparison of the chemical composition and antioxidant stress ability of polysaccharides from Auricularia auricula under different drying methods.

Auricularia auricula fruiting body-derived polysaccharides (AAPs) were dried using different drying procedures, including hot air-, far infrared-, freeze-, and microwave-drying. The influences of different drying procedures on the chemical compositions and antioxidant activity in vitro and in vivo of AAPs were investigated. The results indicated that freeze-dried AAPs (AAPs-F) possessed the highest uronic acid content (33.53%) and the lowest molecular weight (406.77 kDa). Moreover, AAPs-F exhibited the most potent antioxidant abilities in vitro, including ABTS+ and DPPH˙ scavenging abilities, ferric reducing power, and metal ion chelating capacity. Besides, AAPs-F could significantly prolong the lifespan of wild-type C. elegans under oxidative stress induced by H2O2 and methyl viologen (p < 0.05) and upregulate the mRNA expression levels of daf-16 (>2.7 fold), sod-3 (>9.2 fold), skn-1 (>4.5 fold) and sir-2.1 (>1.9 fold), and play a significant role in protecting C. elegans against apoptosis (p < 0.05). Hence, freeze-drying was determined as the preferred procedure for obtaining high-quality AAPs.

Effect of Enzyme-Assisted Extraction on the Chemical Properties and Antioxidant Activities of Polysaccharides Obtained from the Wood Ear Mushroom, Auricularia auricula (Agaricomycetes).

An effective method of polysaccharide extraction from Auricularia auricula (AAPs) by mannanase was developed and optimized by response surface methodology in which the ABTS+ [diammonium 2,2'-azino-bis(3-ethylben-zothiazoline-6-sulfonate radical] scavenging rate was the response. AAPs were graded by stepwise ethanol precipitation with concentrations of 5, 10, 15, and 20% ethanol successively. The fractions with a strong radical scavenging rate were obtained, and then their antioxidant stress effect was studied using Caenorhabditis elegans as a model organism. The ABTS+ scavenging rate of AAPs could reach 37.95 ± 0.53% at a temperature of 55°C, a time of 4 h, a liquid-to-material ratio of 58 mL/1 g, and an enzyme-to-substrate ratio of 2.97%. AAP-20 obtained by 20% ethanol with a strong radical scavenging rate was a heteropolysaccharide composed of mannose, glucose, galactose, xylose, and glucuronic acid. AAP-20 could significantly prolong the lifespan of C. elegans under oxidative stress conditions induced by methyl viologen or hydrogen peroxide, and it could also enhance the activity of antioxidant enzymes including catalase, glutathione reductase, and superoxide dismutase at 0.50 mg/mL (P < 0.05). These studies showed that AAPs prepared with mannanase had a significant protective effect against damage induced by intracellular radical generating agents.

Comparison on chemical features and antioxidant activity of polysaccharides from Auricularia auricula by three different enzymes.

To investigate and compare the chemical features and antioxidant activities of Auricularia auricula polysaccharides (AAPs), three different AAPs (AAP-M, AAP-D, and AAP-C) were prepared by mannanase, ß-dextranase, and cellulase. Their chemical features were determined using high-performance liquid chromatography and infrared spectroscopy. The antioxidant properties were performed both in vitro and in vivo. Results showed that the surface morphology of the A. auricula cell wall treated with three enzymes was slightly different under scanning electron microscopy. The extraction yields of AAP-M, AAP-D, and AAP-C were 18.33% ± 1.93%, 26.42% ± 0.87%, and 17.17% ± 0.08% under optimal conditions, respectively. The monosaccharide composition, molecular weight (AAP-M, AAP-D, and AAP-C were 1.03E+03 kDa, 1.76E+03 kDa, and 1.15E+03 kDa, respectively), and antioxidant activities of the three AAPs were different. AAP-C composed of mannose, glucuronic acid, glucose, and galactose, exhibiting the remarkable ability of scavenging ABTS+ , DPPH, and H2 O2 (IC50 was 0.065, 0.081, and 0.293 mg/ml, respectively). Moreover, AAP-C could significantly prolonged the lifespan of Caenorhabditis elegans under oxidative stress (p < .05). The results showed that cellulase could be served as an efficient enzyme to prepare AAPs with higher antioxidant capacity. PRACTICAL APPLICATIONS: According to the statistics of China Edible Fungi Association in 2019, the output of Auricularia auricula was accounting for 17.54% of the total output of edible fungi. AAPs account for more than 60% of the fruiting bodies and have various biological activities. Cell wall breaking is an important process of extracting AAPs which has always been the bottleneck restricting the production of AAPs. The traditional chemical acid-base method will pollute the environment, and the yield of hot water extraction is low. In contrast, the bioenzyme method widely used because of its mild conditions and environmental friendly. In this paper, three common bioenzymes which have been widely used in food industry were used to extract AAPs, and Box-Behnken design to improve the yield of AAPs. The results show that AAP-C had high yield and strong antioxidant activity. This study could provide a reference for the industrial production of AAPs.

Preparation of Wood Ear Mushroom, Auricularia auricula-judae (Agaricomycetes), Polysaccharides by Neutral Protease and Their Antioxidant Stress Capacity.

Response surface methodology with a Box-Behnken design was used to investigate the effects of a neutral protease on Auricularia auricula-judae polysaccharide (AAP) extraction yield. Four ethanol concentrations (30%, 50%, 70%, and 90%) were used to grade AAPs. Optimal fractions with a high polysaccharide recovery rate and a strong free radical scavenging rate were obtained, and their antioxidant stress effect was studied using Caenorhabditis elegans as the model organism. The results showed that among the factors affecting AAP yield (temperature, liquid-to-A. auricula-judae powder, enzyme usage, time, pH, etc.), temperature, ratio of liquid-to-A. auricula-judae powder, and time had the most obvious effects. AAP yield reached 13.91% ± 0.95% at a temperature of 7°C, liquid-to-material ratio of 75 mL/g, and extraction time of 70 min. High AAP recovery rates and strong free radical scavenging rates of 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) diammonium salt and 1,1-dibenzoyl-2-trinitrophenylhydrazine were obtained by 30% ethanol (AAPs1). Results from the anti-hydrogen peroxide and methyl viologen stress experiment showed that AAPsl could significantly prolong the life of worms under oxidative stress compared to the negative control group (P < 0.05).

The lipid lowering and antioxidative stress potential of polysaccharide from Auricularia auricula prepared by enzymatic method.

An efficient extraction method of Auricularia auricula polysaccharides (AAPs) by neutral protease was developed and optimized by response surface methodology. AAPs were graded by stepwise ethanol precipitation, the fraction with high recovery rate and strong radical scavenging rate were obtained, then its antioxidant and lipid lowering effect were studied using Caenorhabditis elegans as model organism. The extract yield and ABTS+ scavenging rates of AAPs could reach 14.90% and 86.0% at 50 °C, 75 mL/g of liquid-to-material ratio and pH 9.0. AAP3 obtained by 15% ethanol was a heteropolysaccharide comprised of mannose, glucose, glucuronic acid, xylose, galactose and glucosamine. AAP3 could significantly prolong the lifespan of C. elegans and enhance the activity of antioxidant enzymes including superoxide dismutase (SOD), catalases (CAT) at 0.25 mg/mL (p < 0.05). The qRT-PCR results showed that AAP3 could up regulate mRNA expression levels of daf-16 and skn-1 (>1.6 fold) at 0.25 mg/mL. Besides, AAP3 could significantly reduce the level of body fat and triglyceride in C. elegans (p < 0.05). These studies demonstrated that A. auricula polysaccharides prepared by neutral protease had a prominent protective effect to the damage induced by the intracellular free radical generating agents.