Galactomannan Concentrations Research Articles

Mechanism-Based Pharmacokinetic/Pharmacodynamic Model of Voriconazole for Predicting the Clinical Outcomes of Adult Patients with Invasive Aspergillosis.

Voriconazole is the first-line therapy for invasive aspergillosis (IA). To determine the minimum inhibitory concentration of Aspergillus, a voriconazole pharmacokinetic-pharmacodynamic (PK-PD) model linked to galactomannan response was developed and evaluated, and its clinical correlation for IA treatment was elucidated. Adult patients with probable or definite IA and at least one serum voriconazole measurement were included. A two-compartment voriconazole PK model was linked to a previously described PD model of galactomannan response. PK and PD parameters were estimated using a nonparametric adaptive grid technique. The relationship between the ratio of voriconazole exposure that induced half-maximum galactomannan response (EC50) and the observed terminal galactomannan concentration was evaluated. The factors associated with the PK-PD parameters and mortality were also determined. Between January 2013 and December 2022, 41 patients were prescribed voriconazole for IA. The 30-day mortality rate was 17%. A high correlation was found for the observed-predicted Bayesian posterior estimates of voriconazole and galactomannan levels. Moreover, a nonlinear relationship was identified between AUC:EC50 and terminal galactomannan. The factors associated with higher AUC:EC50 were intravenous administration and intubation. In the survival analysis, higher EC50 tended to be associated with mortality, higher AUC was significantly associated with increased mortality, and higher AUC:EC50 tended to be associated with higher mortality. After adjusting for the intravenous route, higher AUC and AUC:EC50 were not associated with mortality. Individual EC50 estimation can provide insights into in vivo host and organism responses. Elevated EC50 showed comparable and unfavorable trends to higher minimum inhibitory concentration. Thus, determining EC50 might help guide individualized target serum voriconazole levels.

Potential diagnostic role of galactomannan and β-D-glucan in occupational asthmatics in wheat mills

Occupational asthma is defined as variable airway obstruction due to exposure to a specific substance in the workplace environment. The aim of the study was to find out the frequency of occupational asthma in wheat mill workers and to explore the role of fungi biomarkers (galactomannan (GM) and β-D-glucan (βDG)) in occupational asthma. Subjects and methods: Assessment of fungi in air was done. Spirometric function of workers (n=120) were assessed during diurnal (before and 15 minutes after inhalation of salbutamol) and nocturnal time. Blood samples were analyzed to measure serum GM and βDG and allergen specific immunoglobulin E. The workers were asked about asthma symptoms. Results and conclusion: A significant proportion of workers had occupational asthma (25%) and only four workers (3.3%) had non-occupational asthma (excluded from the study). The rest were normal (86 workers). Penicillium and Aspergillus were the only species found in the air environment. Mean GM concentration (GM-c) was significantly higher among occupational asthmatics than normal workers. The estimated risk of occupational asthma (Odds ratio) was 13.3 times higher among workers with high GM-c (>1 pg/ml). Ln (GM) was the only significant predictor of PEFR variability. GM has a potential diagnostic role in occupational asthma due to fungal exposure among wheat mill workers. βDG did not have a role in occupational asthma. We recommend that wheat mill flour workers should do periodic spirometric functions and serum GM every 6 - 12 months for early diagnosis and control of occupational asthma.

Comprehensive evaluation of emulsifying and foaming properties of Gleditsia caspica seed galactomannan as a new source of hydrocolloid: Effect of extraction method

The effect of different extraction methods (aqueous, ultrasound-assisted and microwave-assisted extractions) on the emulsifying and foaming aspects of galactomannan obtained from Gleditsia caspica seed as a newly introduced galactomannan was comprehensively investigated in current research. By increasing galactomannan concentration and utilizing ultrasound or microwave in extraction process, the emulsifying capacity, emulsifying stability, zeta potential and foaming stability were remarkably elevated. On the other hand, the values of foaming capacity, z-average, PDI were diminished. Various parameters including the M/G ratio, molecular weight, viscosity, protein content in galactomannan structure and hydrophilic or hydrophobic nature affect the emulsifying and foaming features. By using ultrasound or microwave, the ability of galactomannan in diminishing surface tension was decreased from 83.11 mN/m (for air/water interface) to 54.17, 50.54 and 52.14 mN/m for samples extracted with aqueous, ultrasound and microwave assisted methods. • Emulsifying and foaming aspects of Gleditsia caspica seed galactomannan were comprehensively investigated. • The effect of extraction methods on the emulsifying and foaming aspects of mentioned galactomannan was evaluated. • By increasing galactomannan concentration and utilizing ultrasound or microwave in extraction process, the emulsifying capacity, emulsifying stability, zeta potential and foaming stability were remarkably elevated.

Development of Mucoadhesive Microsphere of Quinapril Hydrochloride for Treatment of Hypertension

Mucoadhesive drug delivery systems are very widely functional approach for delivery of system within the lumen of GIT to enhance drug absorption through the part of stomach with specific manner. Quinapril hydrochloride is the hydrochloride salt of quinapril, the ethyl ester of a non-sulfhydryl, angiotensin-converting enzyme (ACE) inhibitor, quinaprilat. The quinapril hydrochloride microspheres was prepared with a coat consisting of alginate polymer i.e. sodium alginate in combination of mucoadhesive polymer chitosan/ guargum by an ionic gelation process. The microspheres were evaluated for morphological character, particle size, micromeritic properties, percentage entrapment efficiency, in-vitro wash-off test and in-vitro release studies. The drug quinapril hydrochloride was study for the release over 24 h duration. The retarding nature of system maximizing the medication discharge rate at the appropriate site within specified time period for enhancing the bioavailability of drug at desired site of action to give successful treatment to the patients experiencing hypertension The drug release of the microspheres (QLMM1 – QLMM10) was slow, extended and dependent on the composition of galactomannan concentration of polymer and stirring speed during formulation used. The mucoadhesive microspheres were adhered at intestinal pH due to highly swelling nature of composition of polymers at this pH. So, increase the adhesive strength and retarded the drug release of best composition of CH:GG in the ratio of 1:3 (QLMM6). Guargum is a highly viscous material having a property of more swelling nature due to presence of galactommannan constituent. Thus, drug release from QLMM6 was slow and extended over a period of 24 h and these microcapsules were found suitable for oral controlled release formulations.
 Keywords: Gastro-retentive drug delivery, Mucoadhesive microsphere, Quinapril hydrochloride, Pulsatile drug delivery system, Treatment of hypertension, Natural polymers

Kemampuan Ekstrak Galaktomanan dari Ampas Kelapa dalam Menstimulasi Pertumbuhan Bakteri Asam Laktat

This study aimed to determine the ability of galactomannan extract from coconut pulp to stimulate the growth of lactic acid bacteria and to determine the concentration of galactomannan from coconut pulp that could stimulate the growth of lactic acid bacteria with the best growth rate. The experiment was conducted in vitro where the growth medium used was MRS Broth without glucose but added with galactomannan from coconut pulp. MRS Broth media with glucose was used as a control with a concentration of 1%. The galactomannan concentrations used were 0%, 0.5%, 1%, 1.5%, and 2% (w/v). Determination of the confirmed time was carried out by measuring the optical density (OD) on 1.5% galactomannan extract media once every 3 hours. The results showed that galactomannan from coconut pulp can stimulate the growth of lactic acid bacteria. Total lactic acid bacteria related to the degree of acidity and total acid. The more total bacteria, the lower the pH value, thus the total acid will increase. In the media that was added galactomannan from coconut pulp, the best total lactic acid bacteria, pH and total acid were obtained from a concentration of 1% (w/v) with 9 hours incubation, the highest total lactic acid bacteria was 4,5 CFU/mL.
 Keywords: Coconut pulp, galactomannan, lactic acid bacteria

Extraction, Purification, Optimization, and Application of Galactomannan-Based Edible Coating Formulations for Guava Using Response Surface Methodology

Galactomannan from fenugreek and guar seeds were extracted, purified, and used in edible coatings, optimized via response surface methodology. The results showed that the emulsifying capacity and stability of fenugreek galactomannan (FG) and guar galactomannan (GG) increased with increase in the concentration of galactomannan up to 0.5–1%. The average optimized values of FG and GG in edible coatings were predicted to be 1.71% and 2.11% for weight loss, 0.72% and 2.14% for firmness, 1.02% and 1.44% for TSS, 0.83% and 1.36% for pH, 1.03% and 1.44% for acidity, respectively. Significant decrease in weight loss and maximum retention of firmness was observed in coated guava. The TSS increased up to a certain storage period in all treatments and decreased as the storage period progressed, whereas pH exhibited an increasing trend while a significant decrease in acidity was observed. The findings revealed that the shelf life of guava could considerably be improved by incorporating 1.24% galactomannan from GG and 1.01% from FG in the edible coating.

Characterization of hydrophobic interaction of galactomannan in aqueous solutions using fluorescence-based technique

Fluorescence probing was used to study hydrophobic interactions of galactomannan (GM) obtained from fenugreek gum (FG), guar gum (GG), and locust bean gum (LBG) at different M/G ratios. The I1/I3 ratio of pyrene changed from 1.73 to 1.29, 1.22, and 1.29 for FG, GG and LBG, respectively, as the concentration of GM increased from 0.01 to 8.0 g/L at 30 °C. The critical aggregation concentration of FG, GG, and LBG increased from 1.04 to 3.84 g/L, 1.15 to 3.73 g/L, and 0.94 to 3.63 g/L, respectively, as temperature increased from 10 to 70 °C. Addition of Na2SO4 and NaSCN increased the I1/I3 ratio in dilute solution, but reduced it in semi-dilute solution, whereas adding urea reduced I1/I3 in dilute solution but increased it in semi-dilute solution. These results indicated that the CAC of GM, polarity and number of hydrophobic microdomains were highly dependent on the M/G ratio and galactose distribution.

Microstructural and rheological characterization of NaCl-induced gels of soy protein isolate and the effects of incorporating different galactomannans

• Self-supported gels required at least 14% soy protein isolate (SPI) and 200 mM NaCl. • Gels with 300 mM NaCl were stronger, with denser microstructural organizations. • Incomplete demixing varied with galactomannans concentration and branching degree. • Locust bean gum incorporation led to higher microphase separations than guar gum. • Galactomannans addition did not strengthen SPI gels, but increased its stability. This study aimed to evaluate the properties of NaCl-induced gels of soy protein isolate (SPI) in the presence and absence of different galactomannans (locust bean gum - LBG and guar gum – GG) at pH 7. For this purpose, systems with different ionic strengths (100–400 mM), protein concentrations (10–14 %, w/v), and galactomannan concentrations (0–0.5 %, w/v) were evaluated regarding their visual aspects, microstructural organization, and rheological properties. Among the self-supported protein gels (produced with at least 14 % SPI and 200 mM NaCl), those with 300 mM NaCl presented higher G’, G”, and E g values and lower compliance values due to their denser microstructural organization. Such formulations were, therefore, selected for mixed (protein + polysaccharide) gel production. The incorporation of 0.4 % and 0.5 % galactomannans resulted in heat-induced gels, so only samples with 0.1–0.3 % galactomannans were characterized. All mixed gels presented incomplete demixing, but the extent of this phenomenon varied with the concentration of galactomannan and its branching degree. LBG demonstrated higher capacity to self-associate, resulting in gels with higher degrees of phase separation; higher G′, G′′, and E g values; and lower compliance values than GG. Although the galactomannans did not significantly increase the strength of the SPI gels, they increased the stability of the systems at room temperature.

Invasive Tracheobronchial Aspergillosis in Critically Ill Patients with Severe Influenza. A Clinical Trial.

Rationale: Invasive tracheobronchial aspergillosis (ITBA) is an uncommon but severe clinical form of invasive pulmonary aspergillosis in which the fungal infection is entirely or predominantly confined to the tracheobronchial tree.Objectives: To analyze the diagnostic and prognostic differences between tracheobronchial aspergillosis and pulmonary aspergillosis without tracheobronchial lesions among patients admitted to the ICU with severe influenza.Methods: This retrospective, observational study included critically ill patients with influenza associated with pulmonary aspergillosis from three hospital ICUs between 2010 and 2019. Patient characteristics and clinical and mycologic data at admission and during ICU stay were collected in a database to evaluate variables in the two groups.Measurements and Main Results: Thirty-five patients admitted to the ICU with severe influenza and pulmonary aspergillosis were included. Ten patients were included in the group with ITBA (n = 10 of 35; 28.6%), and 25 patients were included in the group without ITBA. The group with ITBA comprised more patients with active smoking, diabetes mellitus, and higher severity scores (Simplified Acute Physiology Score II). Ninety-day mortality rates in the groups with and without ITBA were 90% and 44%, respectively (P = 0.02). Moreover, significantly higher serum 1,3-β-d-glucan and galactomannan and BAL fluid galactomannan concentrations were observed in the group with ITBA compared with the group without ITBA (P < 0.0001, P = 0.003, and P = 0.008, respectively).Conclusions: ITBA was associated with higher severity scores, mortality, and serum and BAL fluid galactomannan and 1,3-β-d-glucan concentrations than invasive pulmonary aspergillosis without tracheobronchial lesions. ITBA should be systematically researched by bronchoscopic examination in ICU patients with concomitant pulmonary aspergillosis and influenza.Clinical trial registered with www.clinicaltrials.gov (NCT04077697).

The physicochemical, texture hardness and sensorial properties of ultrafiltrated low-fat cheese containinggalactomannan and novagel gum.

Today&rsquo;s demand for low-fat dairy products, especially cheeses with favorable qualitative properties such as high-fat cheese, has increased. The main goals of this research are to optimize the textural hardness properties of ultrafiltrated, low-fat cheese (7&ndash;9%), to investigate the possibility of its production with various concentrations of galactomannan and novagel (0.1&ndash;0.5%), and to assess the physicochemical, textural hardness and sensorial properties of the produced low-fat cheese in comparison with full-fat cheese. The textural hardness of the cheeses was tested by a texture analyzer (Stable micro system TA.XT plus Texture, London, UK) equipped with a load cell of 5 kg. The pH values were measured using the&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; pH meter and acidity of the cheese samples according to AOAC standard no. 15004 (AOAC, 1995b). The moisture content and dry matter were measured according to AOAC standard number 920.124 (AOAC, 1995a) as well. The total protein was measured according to AOAC standard no. 991.20 (AOAC, 2005). The amounts of salt and ash were measured according to AOAC (1995a) standard no. 945.46 (AOAC, 1995b), respectively. The results show that the textural hardness properties and sensorial properties of the cheese treatment containing 9% fat, 0.5% galactomannan, and 0.3% novagel are very similar to selected control samples. Meanwhile, optimization of the textural properties of low-fat cheeses via the response-surface method shows that the treatment containing 9% fat, 0.32% novagel and 0.5% galactomannan fulfills the desirable properties of a full-fat cheese up to 100% desirability. The results of this research also show that by using galactomannan and novagel in the formulation of low-fat cheese, it can be produced with favorable texture textural hardness and sensorial properties close to full-fat cheese.

The physicochemical, texture hardness and sensorial properties of ultrafiltrated low-fat cheese containinggalactomannan and novagel gum [pdf

BACKGROUND Today’s demand for low-fat dairy products, especially cheeses with favorable qualitative properties such as high-fat cheese, has increased. The main goals of this research are to optimize the textural hardness properties of ultrafiltrated, low-fat cheese (7–9%), to investigate the possibility of its production with various concentrations of galactomannan and novagel (0.1–0.5%), and to assess the physicochemical, textural hardness and sensorial properties of the produced low-fat cheese in comparison with full-fat cheese. METHODS The textural hardness of the cheeses was tested by a texture analyzer (Stable micro system TA.XT plus Texture, London, UK) equipped with a load cell of 5 kg. The pH values were measured using the pH meter and acidity of the cheese samples according to AOAC standard no. 15004 (AOAC, 1995b). The moisture content and dry matter were measured according to AOAC standard number 920.124 (AOAC, 1995a) as well. The total protein was measured according to AOAC standard no. 991.20 (AOAC, 2005). The amounts of salt and ash were measured according to AOAC (1995a) standard no. 945.46 (AOAC, 1995b), respectively. RESULTS The results show that the textural hardness properties and sensorial properties of the cheese treatment containing 9% fat, 0.5% galactomannan, and 0.3% novagel are very similar to selected control samples. Meanwhile, optimization of the textural properties of low-fat cheeses via the response-surface method shows that the treatment containing 9% fat, 0.32% novagel and 0.5% galactomannan fulfills the desirable properties of a full-fat cheese up to 100% desirability. CONCLUSIONS The results of this research also show that by using galactomannan and novagel in the formulation of low-fat cheese, it can be produced with favorable texture textural hardness and sensorial properties close to full-fat cheese.

Optimization and evaluation of textural properties of ultra-filtrated low-fat cheese containing galactomannan and Novagel gum

The general aim of this research was to optimise textural properties and to evaluate the possibility of producing ultra-filtrated low-fat cheese (7-9 % (w/w)), containing various concentrations of galactomannan and Novagel (0.1-0.5 % w/w), and assessing textural properties of produced low-fat cheeses and comparing them with full fat ones. According to the results, reducing fat implies increasing the hardness, cohesiveness, gumminess and chewiness of the tested samples. On the other hand, adding galactomannan gum and Novagel, and increasing their concentration, implies reducing all of the above mentioned textural properties. According to the results, increasing the amount of fat and using galactomannan and Novagel gum, implies increasing the adhesiveness and springiness of the tested treatments. The results showed that textural properties including hardness, adhesiveness, cohesiveness, gumminess and chewiness, of sample containing 9 % (w/w) fat, 0.5 % (w/w) galactomannan, and 0.3 % (w/w) Novagel were not of significantly different from the control sample and was selected as the superior sample. Multiple optimization of the low-fat cheeses textural properties via Response Surface Method (RSM) software showed that the treatment containing 9 % (w/w) fat, 0.1 % (w/w) Novagel and 0.46% (w/w) galactomannan fulfils 84 % of desirable properties of a full fat cheese.

Galactomannan detection in bronchoalveolar lavage fluid corrected by urea dilution for the diagnosis of invasive pulmonary aspergillosis among nonneutropenic patients.

To investigate the diagnostic performance of galactomannan (GM) detection in bronchoalveolar lavage fluid (BALF) corrected by urea dilution and modification of the AspICU clinical algorithm. GM detection in serum and BALF samples was performed in nonneutropenic patients on the day of clinically suspected invasive pulmonary aspergillosis (IPA) between January 2016 and June 2018, and urea was measured in the plasma and BALF. The BALF GM concentration was corrected by urea dilution, and receiver operating characteristic (ROC) curves were generated to determine the optimal cut-off value. A total of 184 patients who were suspected of IPA, were enrolled in this prospective study together with 30 patients with lung cancer as a control group. Seventy-eight patients were diagnosed with IPA, including 37 who were verified by pathology. The urea plasma-to-urea BALF ratio in the IPA group [4.18 (IQR, 3.52-4.91)] was greater than that in the non-IPA group [3.42 (IQR, 3.12-3.76), P<0.001]. The ROC curve showed that defining the cut-off value as 2.94 optical density index (ODI) for the corrected BALF GM resulted in a sensitivity and specificity of 85.91% and 94.07%, respectively, and was more accurate than the use of the uncorrected values (P<0.05). The corrected BALF GM was valuable for diagnosing IPA in nonneutropenic patients. The modified AspICU clinical algorithm based on this measurement represents a reliable diagnostic instrument in clinical settings.

Fabrication and characterization of an eco-friendly antibacterial nanocomposite of galactomannan/ZnO by in situ chemical co-precipitation method

The present study concerns the methodology for the successful synthesis of galactomannan/ZnO (GM/ZnO) nanocomposite using an in situ chemical co-precipitation route utilizing galactomannan as a nanoreactor. The galactomannan was isolated using a hydrothermal extraction from mezquite (Prosopis spp.) seeds, in which the tree represents a valuable resource for the habitants of arid and semiarid zones of Mexico. The GM/ZnO was synthesized at room temperature. The effects of changing the galactomannan concentration in the nanocomposite over the antibacterial activity against Escherichia coli and Staphylococcus aureus were investigated by microdilution broth method. The GM/ZnO with greatest antibacterial activity was the one with the lowest amount of galactomannan and it was characterized. The ZnO nanoparticles that were observed by SEM and TEM, showed the formation of ZnO nanoparticles, with flake/petal shape and wurtzite structure. The synthesis of nanocomposite was confirmed by FTIR, with strong interactions between the primary alcohol of the galactomannan and ZnO. The thermal stability and decomposition was determined by TGA and DSC, finding a greater thermal stability and an increase of the degradation temperature. A mechanism for the synthesis of GM/ZnO, as well as the formation model of the ZnO with the assistance of the galactomannan are proposed.

In Vitro and In Vivo Efficacy of a Novel and Long-Acting Fungicidal Azole, PC1244, on Aspergillus fumigatus Infection.

ABSTRACTThe antifungal effects of the novel triazole PC1244, designed for topical or inhaled administration, against Aspergillus fumigatus were tested in a range of in vitro and in vivo studies. PC1244 demonstrated potent antifungal activities against clinical A. fumigatus isolates (n = 96) with a MIC range of 0.016 to 0.25 μg/ml, whereas the MIC range for voriconazole was 0.25 to 0.5 μg/ml. PC1244 was a strong tight-binding inhibitor of recombinant A. fumigatus CYP51A and CYP51B (sterol 14α-demethylase) enzymes and strongly inhibited ergosterol synthesis in A. fumigatus with a 50% inhibitory concentration of 8 nM. PC1244 was effective against a broad spectrum of pathogenic fungi (MIC range, <0.0078 to 2 μg/ml), especially Aspergillus terreus, Trichophyton rubrum, Candida albicans, Candida glabrata, Candida krusei, Cryptococcus gattii, Cryptococcus neoformans, and Rhizopus oryzae. PC1244 also proved to be quickly absorbed into both A. fumigatus hyphae and bronchial epithelial cells, producing persistent antifungal effects. In addition, PC1244 showed fungicidal activity (minimum fungicidal concentration, 2 μg/ml) which indicated that it was 8-fold more potent than voriconazole. In vivo, once-daily intranasal administration of PC1244 (3.2 to 80 μg/ml) to temporarily neutropenic, immunocompromised mice 24 h after inoculation with itraconazole-susceptible A. fumigatus substantially reduced the fungal load in the lung, the galactomannan concentration in serum, and circulating inflammatory cytokine levels. Furthermore, 7 days of extended prophylaxis with PC1244 showed in vivo effects superior to those of 1 day of prophylactic treatment, suggesting accumulation of the effects of PC1244. Thus, PC1244 has the potential to be a novel therapy for the treatment of A. fumigatus infection in the lungs of humans.

Efficacy of β-mannanase on broiler growth performance and energy utilization in the presence of increasing dietary galactomannan

An experiment was conducted to investigate the impact of β-mannanase inclusion on growth performance, viscosity, and energy utilization in broilers fed diets varying in galactomannan (GM) concentrations. Treatments were arranged as a 3 (GM concentration) × 3 (β-mannanase inclusion) factorial randomized complete block design with 12 replicates of 29 male broilers per replicate for a 42-d experiment. Efforts were made to reduce the amount of soybean meal, and thus GM, in the basal diet with guar gum included at 0, 0.21, or 0.42% to achieve a GM supplementation of 1,500 and 3,000 ppm, respectively. Beta-mannanase was included at 0, 200, or 400 g/ton. Broilers were fed a starter (d 0 to 14), grower (d 15 to 28), and finisher diets (d 29 to 42). Growth performance was monitored and ileal contents collected on d 14, 28, and 42 to determine ileal digestible energy (IDE) and intestinal viscosity. Increasing levels of GM negatively (P < 0.05) influenced body weight (BW) following the starter and grower periods and increased (P < 0.01) mortality corrected feed conversion ratio (FCR) throughout the study. Reduced growth performance was associated with increased (P < 0.05) intestinal viscosity and decreased (P < 0.05) IDE when GM inclusion was increased. Inclusion of β-mannanase in diets containing supplemental GM on d 28, increased average BW to levels similar to diets without supplemental GM. Improvements in FCR were also observed with β-mannanase inclusion in diets containing supplemental GM. Ileal digestible energy was increased (P < 0.05) with the addition of β-mannanase on d 28 of age. Multiple interactions in growth performance, intestinal viscosity, and IDE were associated with β-mannanase administration. In conclusion, β-mannanase improved IDE, reduced intestinal viscosity, and improved growth performance; however, the observed benefit was dependent upon dietary GM concentration.

In Vivo Biomarker Analysis of the Effects of Intranasally Dosed PC945, a Novel Antifungal Triazole, on Aspergillus fumigatus Infection in Immunocompromised Mice.

ABSTRACTPC945 is a novel triazole optimized for lung delivery, and the objective of this study is to determine the effects of intranasally dosed PC945 on Aspergillus fumigatus infection and associated biomarkers in immunocompromised mice. PC945, posaconazole, or voriconazole was administered intranasally once daily on days 0 to 3 (early intervention) or days 1 to 3 (late intervention) postinfection in temporarily neutropenic A/J mice infected intranasally with A. fumigatus, and bronchoalveolar lavage fluid (BALF) and serum were collected on day 3. The effects of extended prophylaxis treatment (daily from days −7 to +3 or days −7 to 0) were also compared with those of the shorter treatment regimens (days −1 to +3 or days −1 and 0). Early and late interventions with PC945 (2.8 to 350 μg/mouse; approximately 0.11 to ∼14 mg/kg of body weight) were found to inhibit lung fungal loads and to decrease the concentrations of galactomannan (GM) in both BALF and serum as well as several biomarkers in BALF (interferon gamma [IFN-γ], interleukin-17 [IL-17], and malondialdehyde) and serum (tumor necrosis factor alpha [TNF-α] and IL-6) in a dose-dependent manner and were >3- and >47-fold more potent than intranasally dosed posaconazole and voriconazole, respectively. Furthermore, extended prophylaxis with low-dose PC945 (0.56 μg/mouse; 0.022 mg/kg) was found to inhibit fungal loads and to decrease the concentrations biomarkers more potently than did the shorter treatment regimens. Thus, PC945 dosed intranasally once daily showed potent antifungal effects, and the effects of PC945 accumulated upon repeat dosing and were persistent. Therefore, PC945 has the potential to be a novel inhaled therapy for the treatment of A. fumigatus infection in humans.

Understanding β-mannanase from Streptomyces sp. CS147 and its potential application in lignocellulose based biorefining.

Hydrolytic enzymes such as cellulase and hemicellulase have been attracted in lignocellulose based biorefinery. Especially, mannanase has been a growing interest in industrial applications due to its importance in the bioconversion. In this study, an extracellular endo-β-1,4-D-mannanase was produced by Streptomyces sp. CS147 (Mn147) and purified 8.5-fold with a 43.4% yield using Sephadex G-50 column. The characterization of Mn147 was performed, and the results were as follows: molecular weight of ∼25 kDa with an optimum temperature of 50°C and pH of 11.0. The effect of metal ions and various reagents on Mn147 was strongly activated by Ca(+2) but inhibited by Mg(+2) , Fe(+2) , hydrogen peroxide, EDTA and EGTA. Km and Vmax values of Mn147 were 0.13 mg/mL and 294 μmol/min mg, respectively, when different concentrations (3.1 to 50 mg/mL) of locust bean gum galactomannan were used as substrate. In enzymatic hydrolysis of heterogeneous substrate (spent coffee grounds), Mn147 shows a similar conversion compared to commercial enzymes. In addition, lignocellulosic biomass can be hydrolyzed to oligosaccharides (reducing sugars), which can be further utilized for the production of biomaterials. These results showed that Mn147 is attractive in quest of potential bioindustrial applications.

Gelatin and galactomannan-based scaffolds: Characterization and potential for tissue engineering applications

In this work, we produced gelatin films containing different concentrations of galactomannan by casting solutions. The films were crosslinked by immersion in 30mM solution of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC). The crosslinking of gelatin-containing films was confirmed by the reduction of free amine band intensity (3400–3200cm−1) in the GEL IR, as well as by the evaluation of its behavior when immersed in phosphate-buffer solution. The crosslinking of galactomannan film was confirmed by the formation of new ether bonds, as observed by increasing intensity of the band at 1148cm−1, and the reduction of OH band intensity (3600–3200cm−1). The presence of galactomannan and the crosslinking mediated by EDC were responsible to improve elasticity in the gelatin-based films. The samples did not show cytotoxicity during 24h or 48h. In addition, rat mesenchymal stem cells adhered to the films regardless of galactomannan concentration. The results indicated that the gelatin/galactomannan films are potential biomaterials for use as scaffolds for tissue engineering.

Derivation and culture of putative parthenogenetic embryonic stem cells in new gelatin substrates modified with galactomannan

Human embryonic stem cells (ESC) lines to be used for cell therapies must be created and maintained under strict conditions, excluding the use of undefined supplements. Two key steps in the creation of a new embryonic stem cell line are adherence to the substrate and derivation towards the formation of a primary colony. The bovine parthenote embryo model was used to test different matrices of gelatin nanofibers and gelatin/galactomannan films to be used for ESC derivation and culturing. Gelatin/galactomannan films were made in two concentrations of galactomannan, 0.1 and 0.3%, in an aqueous solution of gelatin and tested for gel cytotoxicity using cumulus cells (CCs). CCs showed normal cell morphology, with no sign of lysis or degeneration in any of the matrices tested. Inner cell masses of parthenote blastocysts (n=116) were placed onto the gel matrices for culture. There were three or four repeats for each matrix. Our results showed a good rate of inner cell mass (ICM) adherence on the gelatin/galactomannan films (41%–44%) and one derivative of the gel nanofiber (17% adherence to the substrate). These results encouraged us to try new gelatin formulations to increase the rates of derivation and cell proliferation under defined culture conditions to comply with good manufacturing practice directives for the potential therapeutic use of ESCs.