Improvement of phenolic profile and biological activities of wild mustard sprouts.

The current study aimed to assess the effect of the germination process of wild mustard seeds on the phenolic profile, antioxidant, antibacterial, and antidiabetic properties, and some relevant enzyme activities. The total phenolic and flavonoid contents increased 5- and 10-fold, respectively, and were maximized on 5-days sprouts. One new phenolic compound was identified on 5-days sprout extract using HPLC. The concentrations of the identified phenolic compounds increased 1.5-4.3 folds on 5-days sprouts compared with dry seeds. The total antioxidant activity multiplied 17- and 21-fold on 5-days sprouts using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) assays, respectively. The activity of carbohydrate-cleaving, phenolic-synthesizing and antioxidant enzymes also increased during germination. On 5-days sprouts, there was a substantial correlation between the highest ß-glucosidase and peroxidase activities with highest phenolic and flavonoid levels and maximum antioxidant activity. The phenolic extract of 5-days sprouts exhibited antimicrobial activities against Escherichia coli and Staphylococcus aureus and showed potent antidiabetic activity established by its inhibitory effect against α-amylase and α-glucosidase compared to dry seeds.

Development of chia gum/alginate-polymer support for horseradish peroxidase immobilization and its application in phenolic removal.

Chia gum's molecular structure with distinctive properties as well as the alginate-based hydrogel's three-dimensionally cross-linked structure can provide a potent matrix for immobilization of enzyme. Herein, chia gum (CG)/alginate (A)-polymeric complex was synthesized and employed as a support material for the immobilization of horseradish peroxidase (HRP). HRP was successfully immobilized on the developed ACG-polymeric support, and the highest immobilization recovery (75%) was observed at 1.0% CG and 2% A, pH 7.0, and 50 units of the enzyme. The structure, morphology, and thermal properties of the prepared ACG-HRP were demonstrated using Fourier Transform Infrared (FTIR), Scanning Electron Microscope, and Thermogravimetric (TGA) analyses. ACG-HRP showed a good reusability (60%) over ten reuses. The immobilized ACG-HRP displayed an acidic pH optimum (6.0), a higher temperature optimum (50 °C), and improved thermal stability (30-50 °C) compared to the soluble HRP at pH 7.0, 40 °C and (30-40 °C), respectively. ACG-HRP has a lower affinity for hydrogen peroxide (H2O2) and guaiacol and a higher oxidizing affinity for a number of phenolic substrates. The ACG-HRP demonstrated greater resistance to heavy metals, isopropanol, urea, Triton X-100, and urea, as well as improved efficiency for eliminating phenol and p-chlorophenol. The developed ACG-polymeric support provided improved enzyme properties, allowed the reuse of the immobilized HRP in 10 cycles, and made it promising for several biotechnological applications.

Purification and characterization of cysteine protease of Sarcocystis fusiformis from infected Egyptian water buffaloes.

Sarcocystis spp. infects water buffaloes (Bubalus bubalis) causing sarcocystosis. In the present study, Sarcocystis fusiformis was recognized in Egyptian water buffaloes based on histological observation and molecular analysis of internal transcribed spacer 1 (ITS1), 18S ribosomal RNA (18S rRNA) and cytochrome c oxidase subunit I (COX-1) gene fragments. Chemotherapy and vaccines against Sarcocystis spp. could potentially target proteases because they may play a crucial role in the infection. Cysteine proteases are multifunctional enzymes involved in vital metabolic processes. However, the involvement of proteases in S. fusiform infection has not yet been characterized. Here, the purification and study on some biochemical properties of protease isolated from cysts of S. fusiform were carried out. Protease with a molecular weight of 100 kDa was purified. LC-MS/MS analyzed the protein sequence of purified protease and the data suggested that the enzyme might be related to the cysteine protease. The purified protease exhibited maximum activity at pH 6 and a temperature of 50 °C. The Michaelis-Menten constant (Km), the maximum velocity (Vmax), and the turnover number (Kcat) were determined. The complete inhibition effect of cysteine inhibitors indicated that the purified enzyme is a cysteine protease. The results suggested that S. fusiform proteolytic enzyme may be necessary for parasite survival in water buffaloes by digesting host tissues. Therefore, cysteine protease could be a suitable target for vaccinations.

Biotechnology approach using watermelon rind for optimization of α-amylase enzyme production from Trichoderma virens using response surface methodology under solid-state fermentation.

Production of amylases by fungi under solid-state fermentation is considered the best methodology for commercial scaling that addresses the ever-escalating needs of the worldwide enzyme market. Here response surface methodology (RSM) was used for the optimization of process variables for α-amylase enzyme production from Trichoderma virens using watermelon rinds (WMR) under solid-state fermentation (SSF). The statistical model included four variables, each detected at two levels, followed by model development with partial purification and characterization of α-amylase. The partially purified α-amylase was characterized with regard to optimum pH, temperature, kinetic constant, and substrate specificity. The results indicated that both pH and moisture content had a significant effect (P < 0.05) on α-amylase production (880 U/g) under optimized process conditions at a 3-day incubation time, moisture content of 50%, 30 °C, and pH 6.98. Statistical optimization using RSM showed R2 values of 0.9934, demonstrating the validity of the model. Five α-amylases were separated by using DEAE-Sepharose and characterized with a wide range of optimized pH values (pH 4.5-9.0), temperature optima (40-60 °C), low Km values (2.27-3.3 mg/mL), and high substrate specificity toward large substrates. In conclusion, this study presents an efficient and green approach for utilization of agro-waste for production of the valuable α-amylase enzyme using RSM under SSF. RSM was particularly beneficial for the optimization and analysis of the effective process parameters.

Consensus evidence-based recommendations for treat-to-target management of immunoglobulin A vasculitis.

IgA vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is the most common cause of systemic vasculitis in childhood. Given its potential life-threatening systemic complications, early and accurate diagnosis as well as management of IgAV represent a major challenge for health care professionals. This study was carried out to attain an evidence-based expert consensus on a treat-to-target management approach for IgAV using Delphi technique. The preliminary scientific committee identified a total of 16 key clinical questions according to the patient, intervention, comparison, and outcomes (PICO) approach. An evidence-based, systematic, literature review was conducted to compile evidence for the IgAV management. The core leadership team identified researchers and clinicians with expertise in IgAV management in Egypt upon which experts were gathered from different governorates and health centers across Egypt. Delphi process was implemented (two rounds) to reach a consensus. An online questionnaire was sent to expert panel (n = 26) who participated in the two rounds. After completing round 2, a total of 20 recommendation items, categorized into two sections were obtained. Agreement with the recommendations (rank 7-9) ranged from 91.7-100%. Consensus was reached (i.e. ⩾75% of respondents strongly agreed or agreed) on the wording of all the 20 clinical standards identified by the scientific committee. Algorithms for the diagnosis and management have been suggested. This was an expert, consensus recommendations for the diagnosis and treatment of IgAV and IgA vasculitic nephritis, based on best available evidence and expert opinion. The guideline presented a strategy of care with a pathway to achieve a state of remission as early as possible. PLAIN LANGUAGE SUMMARY: Given its potential life-threatening systemic complications, early and accurate diagnosis of immunoglobulin A vasculitis represents a major challenge for health care professionals. This work provided cornerstone principles for the management of the condition. Adopting PICO approach and implementing Delphi process a consensus was reached on evidence-based treat-to-target treatment recommendations. This will endorse enhancement and consistency of care of this cohort of patients in standard practice.

Egyptian chia seeds (Salvia hispanica L.) during germination: Upgrading of phenolic profile, antioxidant, antibacterial properties and relevant enzymes activities.

Little studies on chia sprouts were not deeply address the polyphenols profiles and their functional properties during long period of germination. This study aims to evaluate the impact of germination process on the phenolic profile, antioxidant and antibacterial properties and relevant enzymes activities of Egyptian chia seeds. The total phenolic and flavonoid contents of chia sprouts increased several times during ten days of germination and maximized on 7-day sprouts (6.4 and 11.5 folds, respectively). In HPLC analysis, seventeen phenolic compounds were detected on 7-day sprouts compared to fifteen in dry seeds, where two new phenolic compounds (p-coumaric acid and kaempferol) were detected. The concentrations of all the identified phenolic compounds increased several folds (1.8-27) on 7-day sprouts. The total antioxidant activity increased 10, 17, and 29 folds on 7-day sprouts using DPPH, ABTS and PMC antioxidant methods, respectively compared to the dry seeds. Both antioxidant and carbohydrate-cleaving enzymes increased in chia sprouts and correlated with their phenolic content and antioxidant activity. The phenolic content of 7-day sprouts showed a potent antibacterial activity against some human enteric pathogenic bacteria including Escherichia coli O157-H7, Salmonella typhi, Pseudomonas aeruginosa and Staphylococcus aureus with lower MIC values compared to the raw seeds.

Purification and characterization of peroxidases from garden cress sprouts and their roles in lignification and removal of phenol and p-chlorophenol.

The study aims to evaluate the relation between peroxidases of day-6 garden cress sprouts and phenolic compounds. Three cationic, three anionic, and two unbounded peroxidases were separated from day-6 garden cress sprouts. Cationic (GCP1) and anionic (GCP2) peroxidases were purified with molecular masses of 25 and 40 kDa, respectively. The Km values of GCP1 toward H2 O2 and guaiacol were lower than GCP2. The anionic GCP2 exhibited high affinity toward some lignin monomers, sinapyl alcohol, coniferyl alcohol, cinnamic and ferulic acids. Therefore, GCP2 is considered as a lignin peroxidase and contributed in lignin synthesis. The activity of GCP1 and GCP2 was stable at a wide pH range 5.5-8.0 and 6.0-7.5, respectively. Both peroxidases showed the same thermal stability range 20-50°C. GCP2 was more resistant against the effect of metal ions than GCP1. GCP2 showed high ability to remove of phenol and p-chlorophenol from effluent compared to GCP1. PRACTICAL APPLICATIONS: Generally, garden cress is used as a test plant to conduct biomonitoring of pollution in urban soil on a wide scale because of its simplicity, sensitivity, and cost-effectiveness. Peroxidase is an important antioxidant enzyme, which elevated when plant subjected to pollution. Recently, we reported that the increase of peroxidase activity was strongly correlated with high phenolic content and antioxidant activity during the germination of garden cress. In the present study, anionic peroxidase GCP2 may play an important role in lignification process and removal of phenol and p-chlorophenol from polluted soil/wastewater as well as resisted the harmful effect of heavy metals. Cationic peroxidase GCP1, as a natural scavenger, had high affinity toward H2 O2 coupled to oxidation of some plant phenolic compounds suggesting its role in consuming of excess H2 O2 .

Age dependent association of inbreeding with risk for schizophrenia in Egypt.

BACKGROUND: Self-reported consanguinity is associated with risk for schizophrenia (SZ) in several inbred populations, but estimates using DNA-based coefficients of inbreeding are unavailable. Further, it is not known whether recessively inherited risk mutations can be identified through homozygosity by descent (HBD) mapping. METHODS: We studied self-reported and DNA-based estimates of inbreeding among Egyptian patients with SZ (n = 421, DSM IV criteria) and adult controls without psychosis (n = 301), who were evaluated using semi-structured diagnostic interview schedules and genotyped using the Illumina Infinium PsychArray. Following quality control checks, coefficients of inbreeding (F) and regions of homozygosity (ROH) were estimated using PLINK software for HBD analysis. Exome sequencing was conducted in selected cases. RESULTS: Inbreeding was associated with schizophrenia based on self-reported consanguinity (χ2 = 4.506, 1 df, p = 0.034) and DNA-based estimates for inbreeding (F); the latter with a significant F × age interaction (ß = 32.34, p = 0.0047). The association was most notable among patients older than age 40 years. Eleven ROH were over-represented in cases on chromosomes 1, 3, 6, 11, and 14; all but one region is novel for schizophrenia risk. Exome sequencing identified six recessively-acting genes in ROH with loss-of-function variants; one of which causes primary hereditary microcephaly. CONCLUSIONS: We propose consanguinity as an age-dependent risk factor for SZ in Egypt. HBD mapping is feasible for SZ in adequately powered samples.

Kinetic and thermodynamic characteristic of Aspergillus awamori EM66 levansucrase.

This study is a new trial aimed to solve levansucrase high cost and levan associated problems during the purification process. Also, kinetic and thermodynamic study was done to compare between the partial pure (PP) and purified forms (PF). Within this context, Aspergillus awamori EM66 levansucrase was produced constitutively (5.44 U.mL-1) using rice straw as the sole medium component. The enzyme was partially purified and was eluted as single protein after two purification steps. Its molecular weight was determined to be 44.5 KDa. The optimum temperature recorded 40 °C for both enzyme forms. While, the purification process lowering the enzyme pH from 5.2 to 4.0. The NaCl concentrations (0.5-3.0 M) pointed to the halophilic nature of the enzyme. The PP form retained about 76% of its original activity after 1 h at 55 °C while the other retained about 57% after 45 min. at the same temperature. The kinetic parameters Km and Vmax concluded that the PF was more efficient than the PP. The thermodynamic parameters such as Ea, Ed, T1/2, D-value, also, ∆G*, ∆H* and ∆ S* for activation recorded that the PP had higher stability than the PF.

Immobilization of Trichoderma harzianum α-amylase on PPyAgNp/Fe3O4-nanocomposite: chemical and physical properties.

In this study, a new support has been developed by immobilization of α-amylase onto modified magnetic Fe3O4-nanoparticles. The characterization of soluble and immobilized α-amylases with regards to kinetic parameters, pH, thermal stability and reusability was studied. The effect of polypyrrole/silver nanocomposite (PPyAgNp) percentage on weight of Fe3O4 and pH on the immobilization of α-amylase was studied. The highest immobilization efficiency (75%) was detected at 10% PPyAgNp/Fe3O4-nanocomposite and pH 7.0. Immobilization of α-amylase on PPyAgNp/Fe3O4-nanocomposite was characterized by FT-IR spectroscopy and scanning electron microscopy. The reusability of the immobilized enzyme activity was 80% of its initial activity after 10 reuses. The immobilized enzyme was more stable towards pH, temperature and metal ions compared with soluble enzyme. The kinetic study appeared higher affinity of immobilized enzyme (Km 2.5 mg starch) compared with soluble enzyme (Km 3.5 mg starch). In conclusion, the immobilization of α-amylase on PPyAgNp/Fe3O4-nanocomposite could successfully be used in industrial and medical applications.

Hepatitis C virus antibody titers associated with cognitive dysfunction in an asymptomatic community-based sample.

BACKGROUND: Hepatitis C virus (HCV) infection is associated with cognitive dysfunction in clinic-based studies. The risk could be attributed to factors such as antiviral medications, substance abuse, or coincidental infection. AIM: The aim was to evaluate cognitive function in relation to HCV antibody titers in a community-based sample of asymptomatic individuals at low risk for substance abuse. METHOD: Adults were ascertained from a community in Mansoura, Egypt, where HCV is endemic (n = 258). Cognitive performance was evaluated using the Arabic version of the Penn Computerized Neurocognitive Battery. Substance abuse and psychopathology were also assessed. Antibodies to HCV and Toxoplasma gondii (TOX), a common protozoan that can affect cognition, were estimated using serological IgG assays. RESULTS: The prevalence of HCV and TOX infection was 17.6% and 52.9%, respectively. HCV antibody titers were significantly associated with worse function in four cognitive tests for accuracy and three tests for speed, after adjusting for covariates (p < .05, beta coefficients, 2.1-3.2). TOX antibody titers were associated with impaired accuracy in one test. CONCLUSIONS: The association between HCV antibody titers and cognitive impairment is not mediated by antiviral treatment or substance abuse in this sample. Whether HCV has a causal role in the cognitive dysfunction should be investigated.

Characterization of two thermostable inulinases from Rhizopus oligosporus NRRL 2710.

Two inulinases (Inu2 and Inu3) were purified from Rhizopus oligosporus NRRL 2710 by chromatography on DEAE-Sepharose and Sephacryl S-200 columns. The molecular weight of Inu2 and Inu3 were determined to be 76 and 30 kDa, respectively. Inu2 and Inu3 had the same pH optimum at 5.0, temperature optimum at 50 and 60 °C, and thermal stability up to 60 and 70 °C for 1 h, respectively. Inu2 and Inu3 had low km values (0.93 and 0.70 mM, respectively) indicating the high affinity toward inulin. Mg2+, Ca2+, Zn2+ and EDTA did not significantly influence the enzyme activity. Ni2+, Cu2+, Fe2+ and Co2+ showed a partial inhibitory effect, and Hg2+ had a strong inhibitory effect. p-Chloromercuribenzoate had a partial inhibitory effect on Inu2. From these findings, R. oligosporus inulinases can be beneficial enzymes for industrial enzymatic production of high fructose syrup.

Arabic versions of the sleep timing questionnaire and the composite scale of morningness.

OBJECTIVES: To develop Arabic versions of English language questionnaires to estimate morningness/eveningness and sleep variables. METHODS: We translated the Composite scale of morningness (CSM) and the sleep timing questionnaire (STQ) [with added siesta questions] into Arabic; the Arabic versions were then back translated. The revised Arabic and the original English versions were next administered to bi-lingual Egyptians using a crossover design (n=25). The Arabic versions of both scales were subsequently administered to an independent Egyptian sample (n=79) and the siesta variables examined in relation to the CSM. RESULTS: Satisfactory correlations were present between the English and Arabic versions for total CSM scores (Spearman's ρ=0.90, p<0.001). All but one of the STQ variables were significantly correlated (Spearman's ρ=0.45-0.88, p≤0.05). In the Arabic version, the frequency of siesta naps per week was significantly correlated with the total CSM score, with evening types taking more naps (Spearman's ρ=-0.23, p≤0.05). CONCLUSIONS: Arabic versions of the STQ and CSM have been developed in Egypt, and are freely available. They can be used for behavioral research related to sleep and circadian function and can be adapted for use in other Arab speaking populations.

Reduced Fertility and Fecundity among Patients with Bipolar I Disorder and Schizophrenia in Egypt.

OBJECTIVE: To evaluate reproduction among patients with bipolar I disorder (BP1) or schizophrenia (SZ) in Egypt. METHODS: BP1 patients (n=113) were compared with community based, demographically balanced controls (n=124) and SZ patients (n=79, DSM-IV). All participants were evaluated using structured interviews and corroborative data were obtained from relatives. Standard indices of procreation were included in multivariate analyses that incorporated key demographic variables. RESULTS: Control individuals were significantly more likely to have children than BP1 or SZ patients (controls 46.8%, BP1 15.9%, SZ 17.7%), but the BP1-SZ differences were non-significant. The average number of children for BP1 patients (0.37±0.9) and SZ patients (0.38±0.9) was significantly lower than for controls (1.04±1.48) (BP1 vs controls, p<0.001; SZ vs controls, p<0.001). The frequency of marriages among BP1 patients was nominally higher than the SZ group, but was significantly lower than controls (BP1: 31.9% SZ: 27.8% control: 57.3%). Even among married individuals, BP1 (but not SZ) patients were childless more often than controls (p=0.001). The marital fertility, i.e., the average number of children among patients with conjugal relationships for controls (1.8±1.57) was significantly higher than BP1 patients (1.14±1.31, p=0.02), but not significantly different from SZ patients (1.36±1.32, p=0.2). CONCLUSION: Selected reproductive measures are significantly and substantially reduced among Egyptian BP1 patients. The reproductive indices are similar among BP1 and SZ patients, suggesting a role for general illness related variables. Regardless of the cause/s, the impairment constitutes important, under-investigated disability.

Does telomere length mediate associations between inbreeding and increased risk for bipolar I disorder and schizophrenia?

We have recently found that consanguinity is a risk factor for bipolar I disorder (BP1) and schizophrenia (SZ) in Egypt. Inbreeding has been associated with increased cellular stress and impaired physiological function in plants and animals. Previous studies have reported that telomere length (TL), an index of oxidative stress and cellular senescence is significantly reduced among patients with SZ or mood disorders compared with control individuals. Hence we evaluated TL as a possible mediator of the observed association between consanguinity and BP1/SZ risk. Patients with BP1 (n=108), or SZ (n=60) were compared with screened adult controls in separate experiments. TL was estimated using a quantitative PCR (qPCR) based assay. The inbreeding coefficient/consanguinity rate was estimated in two ways: using 64 DNA polymorphisms ('DNA-based' rate); and from family history data ('self report'). Significant correlation between TL and DNA based inbreeding was not observed overall, though suggestive trends were present among the SZ cases. No significant case-control differences in TL were found after controlling for demographic variables. In conclusion, reduced TL may not explain a significant proportion of observed associations between consanguinity and risk for BP1/SZ.

Consanguinity and increased risk for schizophrenia in Egypt.

BACKGROUND: Consanguinity has been suggested as a risk factor for psychoses in some Middle Eastern countries, but adequate control data are unavailable. Our recent studies in Egypt have shown elevated parental consanguinity rates among patients with bipolar I disorder (BP1), compared with controls. We have now extended our analyses to schizophrenia (SZ) in the same population. METHODS: A case-control study was conducted at Mansoura University Hospital, Mansoura, Egypt (SZ, n=75; controls, n=126, and their available parents). The prevalence of consanguinity was estimated from family history data ('self report'), followed by DNA analysis using short tandem repeat polymorphisms (STRPs, n=63) ('DNA-based' rates). RESULTS: Self-reported consanguinity was significantly elevated among the patients (SZ: 46.6%, controls: 19.8%, OR 3.53, 95% CI 1.88, 6.64; p=0.000058, 1 d.f.). These differences were confirmed using DNA-based estimates for coefficients of inbreeding (inbreeding coefficients as means+/-standard error, cases: 0.058+/-0.007, controls: 0.022+/-0.003). CONCLUSIONS: Consanguinity rates are significantly elevated among Egyptian SZ patients in the Nile delta region. The associations are similar to those observed with BP1 in our earlier study. If replicated, the substantial risk associated with consanguinity raises public health concerns. They may also pave the way for gene mapping studies.

MEFV mutations in Egyptian patients suffering from familial Mediterranean fever: analysis of 12 gene mutations.

The objective of the study is to screen 12 MEFV gene mutations in Egyptian patients with familial Mediterranean fever (FMF) and to study the initial hypothesis that the phenotypic expression of the disease may be attributable to the existence of a particular mutation. We enrolled 136 Egyptian patients (74 males, and 62 females) with a clinical diagnosis of FMF. DNA was amplified by PCR and subjected to reverse hybridization for the detection of 12 MEFV gene mutations. The phenotypic expression of the disease was compared in two subgroups according to the presence of homozygote E148Q and M694V gene mutations. The most frequent gene mutations in the studied group were V726A, M694V, M680I, E148Q and M694I in 41.2, 32.4, 29.4, 25 and 20.6%, respectively. At least one of these main five founder mutations was present in 132 patients (97.1%). Thirty-two patients (23.5%) were homozygote for one of the main five founder mutations. The most common homozygote gene mutations were E148Q and M694V, each in 12 patients (8.8%). Significant increase in abdominal pain and arthritis was found in patients with homozygote M694V mutation compared to those with E148Q mutation. All patients with amyloidosis had M694V gene mutation. The increased frequency of V726A gene mutation and the rarity of amyloidosis in this study suggest that Egyptian patients may have a milder form of FMF compared to other populations. The five main founder mutations account for the vast majority of cases of FMF. M694V gene mutation may be associated with increased frequency of abdominal pain, arthritis and the presence of amyloidosis.

Consanguinity associated with increased risk for bipolar I disorder in Egypt.

We aimed to contrast rates of consanguinity among patients with bipolar I disorder (BP1) and controls in a population with customary consanguineous marriages (i.e., marriage between related individuals). Consanguinity increases risk for numerous monogenic and polygenic diseases. Whether the risk for BP1 increases with consanguinity has not been investigated systematically. Two independent studies were conducted in Egypt: (1) Case-control study 93 patients with BP1, 90 screened adult control individuals, and available parents. The inbreeding coefficient/consanguinity rate was estimated in two ways: using 64 DNA polymorphisms ("DNA-based" rate); and from family history data ("self report"); (2) Epidemiological survey: total of 1,584 individuals were screened, from whom self-reported consanguinity data were obtained for identified BP1 cases (n = 35) and 150 randomly selected, unaffected control individuals. DNA-based consanguinity rates showed significant case-control differences (P = 0.0039). Self-reported consanguinity rates were also elevated among BP1 patients in both samples (Study #1 OR = 2.66, 95% confidence intervals, CI: 1.34, 5.29; Study #2: OR = 4.64, 95% CI: 2.01, 10.34). In conclusion, two independent, systematic studies indicate increased consanguinity among Egyptian BP1 patients in the Nile delta region. Self-reported estimates of consanguinity are bolstered by DNA-based estimates, and both show significant case-control differences for BP1.

Immobilization of horseradish peroxidase on nonwoven polyester fabric coated with chitosan.

The immobilization of horseradish peroxidase (HRP) on composite membrane has been investigated. This membrane was prepared by coating nonwoven polyester fabric with chitosan glutamate in the presence of glutraldehyde as a crosslinking agent. The physicochemical properties of soluble and immobilized HRP were evaluated. The soluble HRP lost 90% of its activity after 4 weeks of storage at 4 degrees C, whereas the immobilized enzyme retained 85% of its original activity at the same time. A reusability study of immobilized HRP showed that the enzyme retained 54% of its activity after 10 cycles of reuse. Soluble and immobilized HRP showed the same pH optima at pH 5.5. The immobilized enzyme had significant stability at different pH values, where it had maximum stability at pH 3.0 and 6.0. The kinetic properties indicated that the immobilized enzyme had more affinity toward substrates than soluble enzyme. The soluble and immobilized enzymes had temperature optima at 30 and 40 degrees C and were stable up to 40 and 50 degrees C, respectively. The stability of HRP against metal ion inactivation was improved after immobilization. Immobilized HRP exhibited high resistance to proteolysis by trypsin. The immobilized HRP was more resistant to inactivation induced by urea, Triton X-100, and organic solvents compared to its soluble counterpart. The immobilized HRP showed very high yield of immobilization and markedly high stabilization against several forms of denaturants that offer potential for several applications.

Disaccharidase activities in camel small intestine: biochemical investigations of maltase-glucoamylase activity.

Disaccharidases (maltase, cellobiase, lactase, and sucrase), alpha-amylase, and glucoamylase in the camel small intestine were investigated to integrate the enzymatic digestion profile in camel. High activities were detected for maltase and glucoamylase, followed by moderate levels of sucrase and alpha-amylase. Very low activity levels were detected for lactase and cellobiase. Camel intestinal maltase-glucoamylase (MG) was purified by DEAE-Sepharose and Sephacryl S-200 columns. The molecular weight of camel small intestinal MG4 and MG6 were estimated to be 140,000 and 180,000 using Sephacryl S-200. These values were confirmed by SDS-PAGE, where the two enzymes migrated as single subunits. This study encompassed characterization of MGs from camel intestine. The Km values of MG4 and MG6 were estimated to be 13.3 mM and 20 mM maltose, respectively. Substrate specificity for MG4 and MG6 indicated that the two enzymes are maltase-glucoamylases because they catalysed the hydrolysis of maltose and starch with alpha-1,4 and alpha-1,6 glycosidic bonds, but not sucrose with alpha-1,2 glycosidic bond which was hydrolyzed by sucrase-isomaltase. Camel intestinal MG4 and MG6 had the same optimum pH at 7.0 and temperature optimum at 50 degrees C and 40 degrees C, respectively. The two enzymes were stable up to 50 degrees C and 40 degrees C, followed by strong decrease in activity at 60 degrees C and 50 degrees C, respectively. The effect of divalent cations on the activity of camel intestinal MG4 and MG6 was studied. All the examined divalent cations Ca(2+), Mn(2+), Mg(2+), Co(2+) and Fe(3+) had slight effects on the two enzymes except Hg(2+) which had a strong inhibitory effect. The effect of different inhibitors on MG4 and MG6 indicated that the two enzymes had a cysteine residue.