Publications by authors named "Nasri M"

Medium composition and culture conditions for the acid protease production by Aspergillus niger I1 were optimized by response surface methodology (RSM). A significant influence of temperature, KH(2)PO(4), and initial pH on the protease production was evaluated by Plackett-Burman design (PBD). These factors were further optimized using Box-Behnken design and RSM.

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Background: To evaluate the correlation and agreement between central venous saturation (ScvO(2)) and mixed venous saturation (SvO(2)) during cardiopulmonary bypass.

Methods: Twenty-two consecutive patients scheduled for coronary artery surgery were prospectively included. Paired measurements of ScvO(2) and SvO(2) were performed 5 minutes after aortic cross-clamping, after each cardioplegia dose and after de-clamping of the aortic cross-clamp.

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An extracellular protease from Pseudomonas aeruginosa A2 grown in media containing shrimp shell powder as a unique source of nutriments was purified and characterized. The enzyme was purified to homogeneity from culture supernatant by ultrafiltration, Sephadex G-100 gel filtration and Sepharose Mono Q anion exchange chromatography, with a 2.23-fold increase in specific activity and 64.

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The aim of this work was to study some biochemical characteristics of crude alkaline protease extracts from the viscera of goby (Zosterisessor ophiocephalus), thornback ray (Raja clavata), and scorpionfish (Scorpaena scrofa), and to investigate their applications in the deproteinization of shrimp wastes. At least four caseinolytic proteases bands were observed in zymogram of each enzyme preparation. The optimum pH for enzymatic extracts activities of Z.

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Antioxidative activities and biochemical properties of protein hydrolysates prepared from cuttlefish (Sepia officinalis) using Alcalase 2.4 L and Bacillus licheniformis NH1 proteases with different degrees of hydrolysis (DH) were determined. For the biochemical properties, hydrolysis by both enzymes increased protein solubility to above 75% over a wide pH range.

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Different Islamic populations have different alimentary habits, notably during Ramadan. The paper reports the change of diet, lipids, and lipoproteins produced during Ramadan in one Tunisian population. During Ramadan, the study subjects consumed more proteins, cholesterol, vitamin E (p<0.

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Study Purpose: Our objective was the study of the development and the maturation of pups whose mothers were subjected to intermittent fasting.

Materials And Methods: Eight pregnant female Wistar rats were distributed into two groups of four adult females. The rats of the first group were subjected to intermittent fasting beginning on the 14th day of gestation and continued 21 days after parturition.

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Alkaline proteases from the viscera of the striped seabream (Lithognathus mormyrus) were extracted and characterized. Interestingly, the crude enzyme was active over a wide range of pH from 6.0 to 11.

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A Box-Bhenken design with four variables (shrimp shell concentration (SSC), glucose concentration, incubation time and inoculum size) and three levels was used for the determination of the deproteinization and demineralization efficiencies in fermented shrimp shells by Pseudomonas aeruginosa A2. The fermentation variables were selected in accordance with Plackett-Burman design. Maximum demineralization of 96%, with about 89% of protein removal occurs under the following conditions: SSC 50 g/l, glucose 50 g/l, 5 days and inoculum of 0.

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A solvent-stable protease-producing bacterium was isolated and identified as Pseudomonas aeruginosa A2. The strain was found to produce high level of protease activity when grown in media containing only fresh shrimp waste (FSW) or shrimp waste powder (SWP), indicating that it can obtain its carbon, nitrogen, and salts requirements directly from shrimp waste. Maximum protease activities 17,000 and 12,000 U/mL were obtained with 80 g/L SWP and 135 g/L FSW, respectively.

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End-stage renal disease (ESRD) is known to be an important risk factor for cardiac operations performed with cardiopulmonary bypass. We investigated the influence of preoperative status on perioperative mortality and morbidity. We retrospectively analyzed data from 26 patients with ESRD, who were on maintenance dialysis and underwent a cardiac surgical procedure bet-ween 2000 and 2007.

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Cathepsin D from the hepatopancreas of cuttlefish ( Sepia officinalis ) was purified to homogeneity by precipitation with ammonium sulfate (30-60%, w/v), Sephadex G-100 gel filtration, Mono-S cation-exchange chromatography, Sephadex G-75 gel filtration, and Mono-S FPLC with a 54-fold increase in specific activity and 17% recovery. The molecular weight of the purified cathepsin D was estimated to be 37.5 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE).

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Three trypsin isoforms A, B and C were purified to homogeneity from the viscera of sardinelle (Sardinella aurita). Purification was achieved by ammonium sulfate precipitation (20-70% (w/v)), Sephadex G-100 gel filtration and Mono Q-Sepharose anion-exchange chromatography. The molecular weights of these purified enzymes were estimated to be 28.

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An alkaline chymotrypsin from the intestine of striped seabream (Lithognathus mormyrus) was purified by precipitation with ammonium sulfate, Sephadex G-100 gel filtration, Mono Q-Sepharose anion-exchange chromatography, ultrafiltration, second Sephadex G-100 gel filtration, and a second Mono Q-Sepharose anion-exchange chromatography with a 80-fold increase in specific activity. The molecular weight of the purified alkaline chymotrypsin was estimated to be 27 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and size exclusion chromatography. The enzyme was highly active over a wide range of pH from 7.

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This study is concerned with the co-production of alkaline proteases and thermostable alpha-amylase by some feather-degrading Bacillus strains: B. mojavensis A21, B. licheniformis NH1, B.

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Background: In Tunisia the cuttlefish-processing industry generates large amounts of solid wastes. These wastes, which may represent 35% of the original material and constitute an important source of proteins, are discarded without any attempt at recovery. This paper describes some functional properties and the angiotensin I-converting enzyme (ACE)-inhibitory activity of protein hydrolysates prepared by hydrolysis of cuttlefish (Sepia officinalis) by-products with crude enzyme extract from Bacillus licheniformis NH1.

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Media composition and culture conditions for surfactant stable alkaline protease production by Bacillus mojavensis A21 were optimized using two statistical methods. Plackett-Burman design was applied to find the optimal ingredients and conditions to improve yields. Response surface methodology (RSM), including central composite design, was used to determine the optimal concentrations and conditions.

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Antimicrobial peptides (AMPs) are extremely attractive candidates as therapeutic agents due to their wide spectrum of antimicrobial activity and mechanism of action, which differs from that of small-molecule antibiotics. In this study, a 6.0-kDa antimicrobial peptide from Aspergillus clavatus ES1, designated as AcAMP, was isolated by a one-step heat treatment.

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Trypsin from the intestine of smooth hound (Mustelus mustelus) was purified by fractionation with ammonium sulfate, Sephadex G-75 gel filtration, and DEAE-cellulose ion exchange chromatography, with a 65-fold increase in specific activity and 15% recovery. The molecular weight of the purified trypsin was estimated to be 24 kDa using size exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The purified enzyme showed esterase-specific activity on N(alpha)-p-tosyl-L-arginine methyl ester hydrochloride (TAME) that was four times greater than its amidase-specific activity on Nalpha-benzoyl-DL-arginine-p-nitroanilide (BAPNA).

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The angiotensin I-converting enzyme (ACE) inhibitory activities of protein hydrolysates prepared from cuttlefish (Sepia officinalis) proteins by treatment with various bacterial proteases were investigated. The hydrolysate generated by the crude enzyme from Bacillus mojavensis A21 displayed the highest ACE inhibitory activity, and the higher inhibition activity (87.11 +/- 0.

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alpha-Amylase from Bacillus mojavensis A21 (BMA.2) was purified to homogeneity by ultrafiltration, Sephadex G-75 gel filtration and Sepharose mono Q anion exchange chromatography, with a 15.3-fold increase in specific activity and 11% recovery.

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A keratinolytic enzyme (KerA1) secreted by a newly isolated Bacillus pumilus strain A1 cultivated in medium containing chicken feather meal was purified and characterized, and the gene was isolated and sequenced. The molecular mass of the purified enzyme was estimated to be 34,000 Da by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and gel filtration. The optimum pH and temperature for the purified keratinase were 9.

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Chitin is a polysaccharide found in abundance in the shell of crustaceans. In this study, the protease from Bacillus cereus SV1 was applied for chitin extraction from shrimp waste material of Metapenaeus monoceros. A high level of deproteinization 88.

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