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Higher levels of total pepsin and bile acids in the saliva as a possible risk factor for early laryngeal cancer

. Quadeer MA, Lopez R, Wood BG. Does acid suppresive therapy reduce the risk of laryngeal cancer recurrence? Laryngoscope 2005; 115: 1877-81. 8. Copper MP, Smit CF, Stanojcic LD, Devriese PP, Schouwenburg PF Mathus- Vliegen LM. High incidence of laryngeal reflux in patients with head and neck cancer. Laryngoscope 2000; 110: 1007-11. 9. Belafsky PC, Postma GN, Koufman JA. Validity and reliability of the reflux Symptom Index (RSI). J Voice 2002; 16: 274-7. 10. Samuels TL, Johnston N. Pepsin as a marker of extraesophageal

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Using in vitro methods to estimate metabolizable energy content of five forage legumes harvested under different defoliation systems / Einsatz von in vitro Methoden zur Schätzung der umsetzbaren Energie in fünf Futterleguminosen aus unterschiedlichen Nutzungssystemen

Abbreviations OMD, organic matter digestibility; TT, Tilley and Terry method; CM, pepsin-cellulase method; ME, metabolizable energy; WC, white clover; RC, red clover; LC, lucerne; BT, birdsfoot trefoil; KC, kura clover; RG, rotational grazing; CM-OMD, OMD based on pepsin-cellulase method; TTOMD, OMD based on Tilley and Terry method; ME CM , ME estimated by pepsin-cellulase method; ME TT , ME estimated by Tilley and Terry method; MAT, mean average temperature; AP, average precipitation. 1 Introduction With the genetic advancement of new cultivars

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Comparison of Enzymatic Hydrolysis of Polysaccharides from Eggshells Membranes

Abstract

AHyaluronic acid (HA) is part of the extracellular matrix of connective, epithelial and neural tissues, as well as the synovial fluid, skin, and cartilage. It is composed of repeating disaccharide units of D-glucuronic acid and N-acetyl glucosamine. Hyaluronic acid is used in abdominal surgery, ophthalmology, dermatology, rhinology; it is usable for the osteoarthritis treatment. The membranes of eggshell are a natural source of hyaluronic acid, collagen, glycosaminoglycan and collagenous proteins. In paper, we tested the possibility of extraction hyaluronic acid from the eggshell membranes by enzymatic hydrolysis. We identified optimal conditions of hydrolysis with trypsin at reaction temperature of 37 °C and pH 8; with pepsin at 40 °C and pH 3, as well as with papain at 60 °C and pH 7.5. The content of hyaluronic acid in samples was determined spectrophotometrically using the carbazole method. The experimental results showed a yield of ~ 4 -4.5 % hyaluronic acid per 1 g of dry eggshell membranes.

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Evaluation of the ACE-Inhibitory Activity of Egg-White Proteins Degraded with Pepsin

Increasing the potency of antihypertensive food-derived peptides is a critical and important step in the development of natural drugs for cardiovascular diseases prevention. We have proposed the egg-white protein precipitate (EWPP) obtained as a byproduct of cystatin and lysozyme isolation as a potential source of ACE-inhibitory peptides derived by pepsin digestion. The results indicated that hydrolysis of EWPP with pepsin produced the ACE inhibitory activity. During 3-h hydrolysis (DH: 38.3%), the IC50 value of EWPP hydrolysate was significantly increased and finally reached IC50=643.1 μg/mL. This hydrolysate was further fractionated by RP-HPLC. The peptide fraction exhibiting the highest ACE inhibitory activity was rechromatographed. Three peptide subfractions exhibiting ACE-inhibitory activities of 69.0, 25.0, and 37.6 μg/mL were further characterised. In each of them, mixtures of peptides with different molecular masses were observed.

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Healthy Multifunctional Spectra of Milk Glycoproteins and Their Fragments - a Review Article

K., Tomita M., Giehl T.J., Ellison R.T., Antibacterial activity of lactoferrin and a pepsin-derived lactoferrin peptide fragment. Inf. Immun., 1993, 61, 719-728. Ye X.Y., Wang H.X., Liu F., Ng T.B., Ribonuclease, cell-free translation-inhibitory and superoxide radical scavenging activities of the iron-binding protein lactoferrin from bovine milk. Int. J. Biochem. Cell. Biol., 2000, 32, 235-241. Yoo Y.C., Watanabe R., Koike Y., Mitobe M., Shimazaki K., Watanabe S., Azuma I., Apoptosis in human leukemic cells

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SE-HPLC-DAD Analysis of Flaxseed Lignan Macromolecule and its Hydrolysates

SE-HPLC-DAD Analysis of Flaxseed Lignan Macromolecule and its Hydrolysates

A lignan macromolecule (LM) was extracted from defatted flaxseeds using an ethanol-dioxan system (1:1, v/v) and purified using Amberlite column chromatography with water and methanol as mobile phases. The LM was subjected to chemical hydrolysis (base, acid, base & acid), as well as to enzymatic processing using pepsin, pancreatin, cellulase, and β-glucuronidase.

The study revealed that lignan macromolecule in flaxseed was not homogenous. The chemical hydrolysis as well as enzymatic treatment using β-glucuronidase and cellulase released low molecular phenolic compounds from the lignan macromolecule. The liberation of secoisolariciresinol (SECO) and free phenolic acids (p-coumaric and ferulic acids) from flaxseed lignan macromolecule as a result of the base and acid hydrolyses was noted. The application of pepsin and pancreatin did not change the composition of the lignan macromolecule.

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Antioxidative Properties of Bee Pollen Extracts Examined by EPR Spectroscopy

Antioxidative Properties of Bee Pollen Extracts Examined by EPR Spectroscopy

Bee pollen is a valuable and highly recognized source of exogenous antioxidants. The aim of these studies was to determine the antioxidant capacity of three types of bee pollen extracts: ethanol extracts of bee pollen, pepsin extracts of bee pollen and ethanol extracts of pepsin-digested bee pollen. Their antioxidant properties were determined with the use of electron paramagnetic resonance (EPR) and their ability to quench DPPH free radicals was estimated. The EPR results showed that ethanol extracts of pepsin-digested bee pollen (EEPP) had the highest antioxidative effect and the highest free radical DPPH scavenging potential. The pepsin extracts of bee pollen (PEP) had the weakest antioxidant capacity. The ability to quench DPPH free radicals was also the weakest one for this extract. An average antioxidative effect was recorded for ethanol extracts of bee pollen (EEP).

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Effect of Dietary Fibre Fractions on In Vitro Digestibility of Rapeseed Napin Proteins

Abstract

Protein digestibility may be influenced by the presence of dietary fibre affecting the nutritional quality of a feed or food product. This study investigated the interplay between rapeseed (Brassica napus L.) protein and fibre constituents separated by industrially scalable pilot plant processing and recombined in mixed samples. Total dietary fibre (TDF) fractions were isolated from rapeseed hulls (TDF-RH) and purified rapeseed embryo fibres (TDF-RE). The effect of TDF sources on in vitro protein digestibility (IVPD) of a rapeseed protein concentrate rich in napin proteins (RP2) was assessed at three inclusion levels (200, 333, and 500 mg/g DM) using a sequential transient proteolysis by pepsin (1 h) and pancreatin (1 h). The IVPD of RP2 was dose-dependently decreased upon addition of hull fibres at all inclusion levels (8.9-26.6%; P<0.05), whereas the effect of embryo fibres was of a markedly lower magnitude and only significant at the medium to high levels (7.3-8.9%; P<0.05). These results demonstrated that TDF fractions obtained from rapeseed differentially affect the protein digestibility of rapeseed napin proteins depending on the fibre source and inclusion level.

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Type I collagen extracted from rat-tail and bovine Achilles tendon for dental application: a comparative study

Abstract

Background: Collagen has attracted great interest as a biomaterial for various dental and medical uses.

Objective: Investigate the characteristics and biocompatibility of type I collagen extracted from rat-tail tendon and bovine Achilles tendon for dental application.

Materials and methods: Type-I collagen was extracted from rat-tail and bovine Achilles tendon using pepsin. The purity of collagen extracts was examined using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The biocompatibility with human gingival fibroblasts (HGFs) and human oral keratinocytes (HOKs) was examined using an MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Scanning electron microscope (SEM) illustrations of purified collagen alone and collagen with HGFs and HOKs were presented. A three-dimensional wound-healing model of fibroblast populated collagen lattice (FPCL) was used to determine the capability of both sources of collagen to induce wound healing in vitro. Cellular collagen lattices were fabricated to examine the contraction rate of these collagens.

Results: The average yield of collagen extracted from rat-tail and bovine Achilles tendon were 21.8±14.9% and 5.4±0.4%, respectively. The SDS-PAGE analysis showed that the extracts were composed of alpha 1, alpha 2 and beta chains with little contamination of other small proteins. The MTT assay showed good proliferation of cells cultured with each collagen extract, indicating that collagen extracts were non-toxic to the cells. SEM and the FPCL analysis showed that both types of collagen were biocompatible with both HGFs and HOKs, inducing good contraction in the in vitro model.

Conclusion: Type-I collagen extracted from rat-tail and bovine Achilles tendon appeared to be biocompatible with HGFs and HOKs. Both biomaterials may be of use in dental practice.

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What’s new about symptomatic reflux disease

appropriate controls, of gastric acid and pepsin secretion in clinical esophagitis. Gastroenterol. 1991;101:1149-58. 10. Bardhan KD, Muller-Lissner S, Bigard MA, et al. Symptomatic gastrooesophageal reflux disease: double blind controlled study of intermittent treatment with omeprazole or ranitidine. The European Study Group. BMJ. 1999;318:502-7. 11. Miner P Jr, Katz PO, Chen Y, et al. Gastric acid control with esomeprazole, lansoprazole, omeprazole, pantoprazole, and rabeprazole: a fiveway crossover study. Am J Gastroenterol 2003

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