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1.
Trop Anim Health Prod ; 56(8): 334, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39382726

RESUMEN

The aim of this study was to estimate the genetic parameters of the reproductive performance of the Azawak zebu, bred on station during the period 1981 to 2007, in order to contribute to the implementation of an effective selection programme for improving the zootechnical performance of cattle herds. The data contained records of 2453 calvings from 650 Azawak cows, daughters of 55 bulls, all bred at the Toukounous experimental centre (Niger). Non-genetic factors were evaluated using linear mixed models and genetic parameters were estimated using REML procedures with a multi-trait animal model. The effects of year and calving rank were significant (P < 0.001) for the three reproductive traits studied. Heritability was low for age at first calving (h2 = 0.09 ± 0.03) and calf birth weight (h2 = 0.07 ± 0.03). It was moderate for calving interval (h2 = 0.30 ± 0.04) indicating the possibility of genetic improvement of this trait by selection. Repeatability estimates for calf birth weight and calving interval were 0.10 ± 0.02 and 0.42 ± 0.03 respectively. Calving interval had very strong and significant genetic correlations with age at first calving (0.84 ± 0.08) and calf birth weight (-0.40 ± 0.20). There was also a significantly favourable genetic correlation between calf weight at birth and age at first calving (-0.32 ± 0.25), implying a simultaneous improvement in all three reproductive traits through selection. An increase in heritability of calf birth weight was observed after the active phase of the program, reflecting an overly open selection scheme. These genetic parameter estimates suggest that the three reproductive traits could be used in selection index with the aim to improve the three reproductive traits of Azawak cattle.


Asunto(s)
Reproducción , Animales , Bovinos/genética , Bovinos/fisiología , Femenino , Reproducción/genética , Masculino , Niger , Peso al Nacer/genética , Cruzamiento , Embarazo
2.
World J Gastroenterol ; 30(35): 3932-3941, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39351055

RESUMEN

In this editorial, we comment on an article published in the recent issue of the World Journal of Gastroenterology. Celiac disease (CeD) is a disease occurring in genetically susceptible individuals, which is mainly characterized by gluten intolerance in the small intestine and clinical symptoms such as abdominal pain, diarrhea, and malnutrition. Therefore, patients often need a lifelong gluten-free diet, which greatly affects the quality of life and expenses of patients. The gold standard for diagnosis is intestinal mucosal biopsy, combined with serological and genetic tests. At present, the lack of safe, effective, and satisfactory drugs for CeD is mainly due to the complexity of its pathogenesis, and it is difficult to find a perfect target to solve the multi-level needs of patients. In this editorial, we mainly review the pathological mechanism of CeD and describe the current experimental and improved drugs for various pathological aspects.


Asunto(s)
Enfermedad Celíaca , Dieta Sin Gluten , Enfermedad Celíaca/diagnóstico , Enfermedad Celíaca/terapia , Enfermedad Celíaca/fisiopatología , Enfermedad Celíaca/dietoterapia , Humanos , Mucosa Intestinal/patología , Mucosa Intestinal/fisiopatología , Mucosa Intestinal/efectos de los fármacos , Calidad de Vida , Biopsia , Predisposición Genética a la Enfermedad , Intestino Delgado/fisiopatología , Intestino Delgado/patología
3.
Microb Cell Fact ; 23(1): 262, 2024 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-39367393

RESUMEN

D-Xylitol is a naturally occurring sugar alcohol present in diverse plants that is used as an alternative sweetener based on a sweetness similar to sucrose and several health benefits compared to conventional sugar. However, current industrial methods for D-xylitol production are based on chemical hydrogenation of D-xylose, which is energy-intensive and environmentally harmful. However, efficient conversion of L-arabinose as an additional highly abundant pentose in lignocellulosic materials holds great potential to broaden the range of applicable feedstocks. Both pentoses D-xylose and L-arabinose are converted to D-xylitol as a common metabolic intermediate in the native fungal pentose catabolism.To engineer a strain capable of accumulating D-xylitol from arabinan-rich agricultural residues, pentose catabolism was stopped in the ascomycete filamentous fungus Aspergillus niger at the stage of D-xylitol by knocking out three genes encoding enzymes involved in D-xylitol degradation (ΔxdhA, ΔsdhA, ΔxkiA). Additionally, to facilitate its secretion into the medium, an aquaglyceroporin from Saccharomyces cerevisiae was tested. In S. cerevisiae, Fps1 is known to passively transport glycerol and is regulated to convey osmotic stress tolerance but also exhibits the ability to transport other polyols such as D-xylitol. Thus, a constitutively open version of this transporter was introduced into A. niger, controlled by multiple promoters with varying expression strengths. The strain expressing the transporter under control of the PtvdA promoter in the background of the pentose catabolism-deficient triple knock-out yielded the most favorable outcome, producing up to 45% D-xylitol from L-arabinose in culture supernatants, while displaying minimal side effects during osmotic stress. Due to its additional ability to extract D-xylose and L-arabinose from lignocellulosic material via the production of highly active pectinases and hemicellulases, A. niger emerges as an ideal candidate cell factory for D-xylitol production from lignocellulosic biomasses rich in both pentoses.In summary, we are showing for the first time an efficient biosynthesis of D-xylitol from L-arabinose utilizing a filamentous ascomycete fungus. This broadens the potential resources to include also arabinan-rich agricultural waste streams like sugar beet pulp and could thus help to make alternative sweetener production more environmentally friendly and cost-effective.


Asunto(s)
Arabinosa , Aspergillus niger , Ingeniería Metabólica , Xilitol , Aspergillus niger/metabolismo , Aspergillus niger/genética , Arabinosa/metabolismo , Xilitol/metabolismo , Xilitol/biosíntesis , Ingeniería Metabólica/métodos , Xilosa/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Proteínas Fúngicas/metabolismo , Proteínas Fúngicas/genética
4.
3 Biotech ; 14(11): 259, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39372493

RESUMEN

The current research focuses on the production and optimization of a natural yellowish-brown Azaphilone dye using Aspergillus niger. A variety of culture media were tested to ascertain the best conditions for dye synthesis. The formation of the yellowish-brown dye was confirmed by a color shift in the reaction mixture, and UV-Vis spectroscopy detected the dye at 450 nm. Static conditions were found to be more favorable than shaking for higher dye yields, and fed-batch fermentation was more effective than batch fermentation. Maximum dye production was achieved after 28 days of incubation. Factors such as temperature, pH, and inoculum percentage were shown to influence dye synthesis, with the highest production (2.5 ml) occurring at 30 °C, pH 7, and a 3% spore suspension in yeast extract peptone broth (YEPB) medium under static conditions. Gas chromatography-mass spectrometry (GC-MS) analysis validated the presence of Azaphilone dye in the culture filtrate. The dye was successfully applied to a pretreated cotton cloth. These findings advance our understanding of optimizing fungal dye production for sustainable and eco-friendly textile coloration applications. This study appears to be the first of its kind to report azaphilone dye production by A. niger in the YEPB medium.

5.
Microbiol Spectr ; : e0190624, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377610

RESUMEN

For over a century, the filamentous Ascomycete fungus Aspergillus niger has played a pivotal role in the industrial production of citric acid. A critical fermentation parameter that sustains high-yield citric acid accumulation is the suboptimal concentration of manganese(II) ions in the culture broth at the early stages of the process. However, the requirement for this deficiency has not been investigated on a functional genomics level. In this study, we compared the transcriptome of the citric acid hyper-producer A. niger NRRL2270 strain grown under citric acid-producing conditions in 6-L scale bioreactors at Mn2+ ion-deficient (5 ppb) and Mn2+ ion-sufficient (100 ppb) conditions at three early time points of cultivation. Of the 11,846 genes in the genome, 963 genes (8.1% of the total) were identified as significantly differentially expressed under these conditions. Disproportionately high number of differentially regulated genes encode predicted extracellular and membrane proteins. The most abundant gene group that was upregulated in Mn2+ ion deficiency condition encodes enzymes acting on polysaccharides. In contrast, six clusters of genes encoding secondary metabolites showed downregulation under manganese deficiency. Mn2+ deficiency also triggers upregulation of the cexA gene, which encodes the citrate exporter. We provide functional evidence that the upregulation of cexA is caused by the intracellular accumulation of citrate or acetyl-CoA and is a major factor in triggering citrate overflow. IMPORTANCE: Citric acid is produced on industrial scale by batch fermentation of the filamentous fungus Aspergillus niger. High-yield citric acid production requires a low (<5 ppb) manganese(II) ion concentration in the culture broth. However, the requirement for this deficiency has not been investigated on a functional genomics level. Here, we compared the transcriptome of a citric acid hyper-producer A. niger strain grown under citric acid-producing conditions in 6-L scale bioreactors at Mn2+ ion-deficient (5 ppb) and Mn2+ ion-sufficient (100 ppb) conditions at three early time points of cultivation. We observed that Mn2+ deficiency triggers an upregulation of the citrate exporter gene cexA and provides functional evidence that this event is responsible for citrate overflow. In addition to the industrial relevance, this is the first study that examined the role of Mn2+ ion deficiency in a heterotrophic eukaryotic cell on a genome-wide scale.

6.
Nat Prod Res ; : 1-7, 2024 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-39371032

RESUMEN

Gardeniae Fructus, the dried fruit of Gardenia jasminoides, was fermented with Aspergillus niger DQWM-G11. The antibacterial activities of the fermented and non-fermented products were measured and the transformation of chemical constituents was detected. The results revealed that A. niger DQWM-G11 fermented Gardeniae Fructus (AFGF) possessed a stronger antibacterial effect with a minimal inhibitory concentration (MIC) value of 256 µg/mL, compared to the raw material (MIC: > 1024 µg/mL). An undescribed microbial transformation reaction was discovered, where geniposide (1) was transformed into 1ß-methoxyl-4-epigardendiol (2), which was then verified. The produced component exhibited a stronger antibacterial effect (MIC: 256 µg/mL) than raw geniposide (1) (MIC: >1024 µg/mL), indicating that the increased activity of Gardeniae Fructus was due to the biotransformation. The discovery of this microbial transformation reaction will provide an important theoretical basis for further developing and applying Gardeniae Fructus and geniposide.

7.
Infect Dis Now ; : 104979, 2024 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-39313157

RESUMEN

BACKGROUND: Diphtheria is a re-emerging bacterial disease in developing countries with low vaccination coverage. OBJECTIVES: This is a descriptive cross-sectional study of diphtheria cases reported to the DRSP/Zinder from March 14, 2022 through June 26, 2023. METHODS: It includes cases reported through epidemiological surveillance and data on patients hospitalized in the infectious and tropical diseases department of the Zinder National Hospital (SMIT). RESULTS: A total of 32 patients were included in this study. The median age was 12 years [4-22 years]. Key symptoms included dysphagia and odynophagia (100 %), false membranes (84.4 %), fever (46.9 %), thrombocytopenia (39.3 %), cervical lymphadenopathy (37 %), respiratory distress (15.6 %), epistaxis (12.5 %), gingival bleeding (9.4 %), agitation (6.2 %) and paresis (3.1 %). Renal function was altered in 74 % of cases. Diagnostic confirmation was procured through culture on oropharyngeal swabs. Corynebacterium diphtheriae was isolated in 26.31 % (5/19) of cases. Patients were treated with macrolides and diphtheria antitoxin. The case fatality rate was 31.2 %. Poor prognostic factors included gingival bleeding (p = 0.0262), respiratory distress (p = 0.0374), and thrombocytopenia below 50,000 platelets/mm3 (p = 0.0020). CONCLUSION: Diphtheria is a deadly re-emerging disease. The fight against this condition necessitates improved vaccination coverage.

8.
Fungal Biol Biotechnol ; 11(1): 13, 2024 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-39223615

RESUMEN

Laccases are multi-copper oxidases that are usually composed of three Cu-oxidase domains. Domains one and three house the copper binding sites, and the second domain is involved in forming a substrate-binding cleft. However, Streptomyces species are found to have small laccases (SLAC) that lack one of the three Cu-oxidase domains. This type of SLAC with interesting lignocellulose bioconversion activities has not been reported in Aspergillus niger. In our research, we explored the expression and engineering of the SLAC from Streptomyces leeuwenhoekii C34 in A. niger. Genes encoding two versions of the SLAC were expressed. One encoding the SLAC in its native form and a second encoding the SLAC fused to two N-terminal CBM1 domains. The latter is a configuration also known for specific yeast laccases. Both SLAC variants were functionally expressed in A. niger as shown by in vitro activity assays and proteome analysis. Laccase activity was also analyzed toward bioconversion of lignocellulosic rice straw. From this analysis it was clear that the SLAC activity improved the efficiency of saccharification of lignocellulosic biomass by cellulase enzyme cocktails.

9.
Biotechnol Lett ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235649

RESUMEN

The α-L-rhamnosidase (rha1) gene was homologously expressed in Aspergillus niger strains CCTCC 206047 and CCTCC 206047ΔpyrG, using hygromycin B and auxotrophic as selection markers. The engineered A. niger strains RHA001-1 and RHA003-1 were screened, yielding α-L-rhamnosidase activities of 20.81 ± 0.56 U/mL and 15.35 ± 0.87 U/mL, respectively. The copy numbers of the rha1 gene in strains RHA001-1 and RHA003-1 were found to be 18 and 14, respectively. Correlation analysis between copy number and enzyme activity in the A. niger strains revealed that α-L-rhamnosidase activity increased with the copy number of the rha1 gene. Recombinant α-L-rhamnosidase was utilized for the enzymatic debittering of Ougan juice, and its process conditions were optimized. Furthermore, the primary bitter substance neohesperidin (2.22 g/L) in Ougan juice was converted into hesperetin 7-O-glucoside (1.47 g/L) and hesperidin (0.143 g/L). This study presents a novel approach for the production of food-grade α-L-rhamnosidase and establishes a technical foundation for its application in the beverage industry.

10.
Foods ; 13(17)2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39272590

RESUMEN

The use of black soldier fly (BSF) larvae and frass in agriculture can make an important contribution to food and nutrition security. However, it is important to understand whether consumers are willing to consume food products resulting from the use of BSF larvae as animal feed or BSF frass as fertilizer. This study employed the stated preference approach as food products produced using BSF larvae and frass are not currently available on the market. Questionnaires were administered to a total of 4412 consumers in Ghana (1360), Mali (1603), and Niger (1449). The results show that the vast majority of respondents are willing to consume vegetables (88%) produced using BSF frass and meat (87%) produced using animal feed made of BSF larvae. A smaller percentage of respondents are even willing to pay USD 1.32 and USD 1.7 more if the base price of BSF-based products were USD 5 per kg. Age, gender, education, and country positively influenced the respondents' willingness to consume food produced using BSF products. In contrast, neighborhood status, income, and household size are inversely related to the respondents' willingness to pay for and consume these products. Our findings are, therefore, important to scaling up BSF technologies in the region.

11.
Phytochemistry ; 229: 114272, 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39260588

RESUMEN

Phytochemical investigation of the whole plants of Helleborus niger L. (Ranunculaceae) resulted in the isolation of five undescribed compounds, including one bufadienolide (1), two bufadienolide rhamnosides (2 and 3), and two ecdysteroids (12 and 13), along with eight known compounds (4-11). The chemical structures of 1-3, 12, and 13 were determined by spectroscopic studies, including 2D NMR, and chromatographic and spectroscopic analyses of the hydrolyzed products. Compounds 1-13 were evaluated for their cytotoxic activity against HL-60 human leukemia cells, A549 human lung adenocarcinoma cells, SBC-3 human small-cell lung cancer cells, and TIG-3 human normal diploid lung cells. Compounds 1-12 showed cytotoxic activity against HL-60, A549, and SBC-3 cells, with IC50 values ranging from 0.0016 to 6.1 µM. Bufadienolide rhamnoside 2 exhibited potent cell proliferation inhibitory activity against SBC-3 cells after 24-48 h of treatment and apoptosis-inducing activity in SBC-3 cells via an intrinsic pathway after 72 h of treatment. The JFCR39 panel screening of 2 suggests that the molecular target of 2 is Na+,K+-ATPase.

12.
BMC Res Notes ; 17(1): 257, 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39256846

RESUMEN

The glycoside hydrolase family 3 (GH3) ß-glucosidases from filamentous fungi are crucial industrial enzymes facilitating the complete degradation of lignocellulose, by converting cello-oligosaccharides and cellobiose into glucose. Understanding the diverse domain organization is essential for elucidating their biological roles and potential biotechnological applications. This research delves into the variability of domain organization within GH3 ß-glucosidases. Two distinct configurations were identified in fungal GH3 ß-glucosidases, one comprising solely the GH3 catalytic domain, and another incorporating the GH3 domain with a C-terminal fibronectin type III (Fn3) domain. Notably, Streptomyces filamentous bacteria showcased a separate clade of GH3 proteins linking the GH3 domain to a carbohydrate binding module from family 2 (CBM2). As a first step to be able to explore the role of accessory domains in ß-glucosidase activity, a screening system utilizing the well-characterised Aspergillus niger ß-glucosidase gene (bglA) in bglA deletion mutant host was developed. Based on this screening system, reintroducing the native GH3-Fn3 gene successfully expressed the gene allowing detection of the protein using different enzymatic assays. Further investigation into the role of the accessory domains in GH3 family proteins, including those from Streptomyces, will be required to design improved chimeric ß-glucosidases enzymes for industrial application.


Asunto(s)
Ingeniería de Proteínas , Streptomyces , beta-Glucosidasa , Streptomyces/enzimología , Streptomyces/genética , beta-Glucosidasa/genética , beta-Glucosidasa/metabolismo , beta-Glucosidasa/química , Ingeniería de Proteínas/métodos , Biotecnología/métodos , Aspergillus niger/enzimología , Aspergillus niger/genética , Dominios Proteicos , Aspergillus/enzimología , Aspergillus/genética , Proteínas Fúngicas/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Dominio Catalítico , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química
13.
Sci Rep ; 14(1): 20554, 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39232039

RESUMEN

This study presents the findings of a comprehensive geotechnical and seismic site investigation conducted at Otuasega Town located in Bayelsa State within the Niger Delta region of Nigeria. Subsurface exploration involved advancing 10 boreholes to 30 m depth using hollow stem auger drilling. Continuous disturbed and undisturbed soil sampling was performed at 1.5 m intervals for detailed geotechnical testing. Laboratory tests on the recovered soil samples established the index properties, classification, densities and consistency limits of the stratified deposits. The subsurface profile comprised alternating layers of clay, silt and sand typical of deltaic sediments, with the clay fractions exhibiting medium to high plasticity. Shear wave velocity (Vs) profiling using Multichannel Analysis of Surface Waves (WASW) techniques categorised the site predominantly as Site Class C and D based on international standards. The Standard Penetration Test (SPT) N-values ranged from 5 to 10, indicating soft normally consolidated clay conditions typical of the Niger Delta region. Predictive empirical models developed from the field and lab data showed strong correlations for estimating key geotechnical parameters such as SPT blow count, Vs and liquefaction resistance. Ground response analyses using the Vs and SPT data indicated significant site amplification potential, with peak ground accelerations up to 1.5 times the bedrock motion. Liquefaction analysis based on the empirical SPT-based methods revealed a high potential for liquefaction in the sandy layers, especially under strong earthquake shaking. The study characterized the complex sedimentology and provided baseline information for seismic microzonation and site-specific ground response analyses to advance understanding of geohazards in this delta environment.

14.
Microorganisms ; 12(9)2024 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-39338603

RESUMEN

The utilization of agroindustrial residues, such as avocado peel, as a source of bioactive compounds with antioxidant properties has garnered significant attention. In this study, we investigated the antioxidant potential using the DPPH (2,2-diphenyl-1-picrylhydrazyl) and ORAC (oxygen radical absorbance capacity) methods, along with the antimicrobial activity of phenolic compounds extracted from Hass avocado peel. These soluble polyphenols were quantified and identified using high-performance liquid chromatography (HPLC). The research focused on their effects against three fungal pathogens, Verticillium theobromae, Colletotrichum musae, and Aspergillus niger, which significantly impact banana crops, an essential agricultural commodity in Ecuador. The results have revealed that the application of 80% ethanol as an organic solvent led to increased soluble polyphenol content compared to 96% ethanol. Extraction time significantly influenced the phenolic content, with the highest values obtained at 90 min. Interestingly, despite substantial mycelial growth observed across all extract concentrations, the antifungal effect varied among the pathogens. Specifically, V. theobromae exhibited the highest sensitivity, while C. musae and A. niger were less affected. These results underscore the importance of considering both antioxidant and antimicrobial properties when evaluating natural extracts for potential applications in plant disease management.

15.
BMC Infect Dis ; 24(1): 990, 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39289609

RESUMEN

BACKGROUND: Aspergillus spp. are rare causes of surgical site infections (SSIs). Specifically, Aspergillus section Nigri, commonly identified as Aspergillus niger through morphological findings, has infrequently been reported as an abdominal SSI pathogen. CASE PRESENTATION: An 86-year-old woman with a history of hypertension, chronic kidney disease, and atrial fibrillation who was taking 6 mg of prednisolone daily for rheumatoid arthritis was admitted to our hospital because of sudden abdominal pain. She was diagnosed with sigmoid colon perforation and underwent an open Hartmann operation on the day of admission. Subsequently, a superficial abdominal SSI was detected. Through analysis of the calmodulin gene, Aspergillus welwitschiae, which is classified within the Aspergillus section Nigri, was identified as the responsible pathogen. The minimum inhibitory concentration of voriconazole (VRCZ) was 2 mg/L. Surgical removal of the infected tissue and VRCZ administration was effectively used to treat the infection. CONCLUSIONS: Given the reported low susceptibility of Nigri section species to azoles, identification and drug susceptibility testing of these fungi are highly important.


Asunto(s)
Antifúngicos , Aspergilosis , Aspergillus , Infección de la Herida Quirúrgica , Humanos , Femenino , Anciano de 80 o más Años , Aspergillus/aislamiento & purificación , Aspergillus/genética , Aspergillus/efectos de los fármacos , Aspergilosis/microbiología , Aspergilosis/tratamiento farmacológico , Aspergilosis/diagnóstico , Infección de la Herida Quirúrgica/microbiología , Infección de la Herida Quirúrgica/tratamiento farmacológico , Antifúngicos/uso terapéutico , Voriconazol/uso terapéutico , Pruebas de Sensibilidad Microbiana
16.
BMC Biotechnol ; 24(1): 69, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39334195

RESUMEN

The present study deals with the production of cellulase-free endoxylanase by Aspergillus niger ISL-9 using wheat bran as a solid substrate. Endoxylanase was produced under a solid-state fermentation. Various growth parameters were optimized for the improved production of the enzyme. The Substrate level of 15 g was optimized as it provided the fungus with balanced aeration and nutrition. Among the six moisture contents investigated, Moisture Content 5 (MC5) was optimized (g/l: malt extract, 10; (NH4)2HPO4, 2.5; urea, 1.0) and 10 mL of MC5 was found to give the highest production of endoxylanase. The pH and time of incubation were optimized to 6.2 and 48 h respectively. The Inoculum size of 2 mL (1.4 × 106 spores/mL) gave the maximum enzyme production. After optimization of these growth parameters, a significantly high endoxylanase activity of 21.87 U/g was achieved. Very negligible Carboxymethylcellulase (CMCase) activity was observed indicating the production of cellulase-free endoxylanase. The notable finding is that the endoxylanase activity was increased by 1.4-fold under optimized conditions (p ≤ 0.05). The overall comparison of kinetic parameters for enhanced production of endoxylanase by A. niger ISL-9 under Solid State Fermentation (SSF) was also studied. Different kinetic variables which included specific growth rate, product yield coefficients, volumetric rates and specific rates were observed at 48, 72 and 96 h incubation time and were compared for MC1 and MC5. Among the kinetic parameters, the most significant result was obtained with volumetric rate constant for product formation (Qp) that was found to be optimum (1.89 U/h) at 72 h incubation period and a high value of Qp i.e.1.68 U/h was also observed at 48 h incubation period. Thus, the study demonstrates a cost-effective and environmentally sustainable process for xylanase production and exhibits scope towards successful industrial applications.


Asunto(s)
Aspergillus niger , Fibras de la Dieta , Endo-1,4-beta Xilanasas , Fermentación , Aspergillus niger/enzimología , Aspergillus niger/metabolismo , Fibras de la Dieta/metabolismo , Endo-1,4-beta Xilanasas/metabolismo , Endo-1,4-beta Xilanasas/biosíntesis , Cinética , Concentración de Iones de Hidrógeno , Medios de Cultivo/metabolismo , Medios de Cultivo/química
17.
Open Forum Infect Dis ; 11(9): ofae474, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39282631

RESUMEN

Background: Niger's National Malaria Control Programme and its partners use histidine-rich protein 2-based RDTs, which are specific to Plasmodium falciparum diagnosis. This study aimed to screen for the circulation of non-falciparum species in Zinder, a region of Niger, West Africa. Methods: A cross-sectional study was carried out from July to December 2022 at the district hospital of the Zinder region of Niger. P falciparum histidine-rich protein 2-based rapid diagnostic tests were performed, and dried blood spot samples were collected for further laboratory multiplexed photo-induced electron transfer-polymerase chain reaction (PET-PCR) analysis on positive light microscopy from all patients with fever who attended the Zinder district hospital during the study period. Results: In total, 340 dried blood spots were collected and analyzed by PET-PCR. Overall, 73.2% (95% CI, 68.2%-77.9%; 249/340) were positive for Plasmodium genus and species and represented the study population. Plasmodium species proportions were 89.5% (95% CI, 85.1%-93.1%; 223/249) for P falciparum, 38.5% (95% CI, 32.5%-44.9%; 96/249) for P malariae, 10.8% (95% CI, 7.3%-15.4%; 27/249) for P vivax, and 1.6% (95% CI, .4%-4.1%; 4/249) for P ovale. Single infection with Plasmodium species counted for 61.8% (95% CI, 55.5%-67.9%; 154/249), and the mixed infections rate, with at least 2 Plasmodium species, was 38.1% (95% CI, 32.1%-44.5%; 95/249). Single non-falciparum infections represented a rate of 10.0% (95% CI, 6.6%-14.5%; 25/249). Conclusion: This study confirms the first evidence of Plasmodium vivax by PET-PCR in Niger in addition to the other 3 Plasmodium species. These findings underline the need to adapt malaria diagnostic tools and therapeutic management, as well as the training of microscopists, for recognition of non-falciparum plasmodial species circulating in the country. This will better inform the strategies toward malaria control and elimination, as well as the decision making of the health authorities of Niger.

18.
Cureus ; 16(8): e67203, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39295670

RESUMEN

Insomnia is a widespread disease that tends to be associated with other problems, like anxiety. The most frequent anxiety disorder is generalized anxiety disorder (GAD), which is characterized by excessive worrying about everyday situations. Medications for insomnia and anxiety can have adverse reactions and the latter may be ineffective in up to 30% of patients. Here we present a case report of a 27-year-old male patient who suffered from persistent insomnia with comorbid GAD and schizophreniform disorder. Initially, he was taking alprazolam, paroxetine, and risperidone, which had a less-than-satisfactory effect. He was treated with individualized homeopathy, which produced a remarkable improvement within four months. This was evidenced by a decrease in difficulty falling asleep and daytime sleepiness; in addition, anxiety and its accompanying symptoms, such as irritability and diaphoresis, were reduced. This improvement persists for up to one year after the commencement of treatment and despite discontinuation of all medications. This clinical report provides preliminary evidence that persistent insomnia and comorbid GAD can be treated successfully with individualized homeopathy. However, further randomized controlled studies are needed to evaluate its efficacy, effectiveness, and safety more conclusively.

19.
Mar Pollut Bull ; 208: 117008, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39299188

RESUMEN

Mercury pollution from ongoing crude oil refining and waste disposal activities threatens aquatic ecosystems and human health in the Niger Delta. Mercury monitoring exercise in this region is challenging due to the high cost of traditional instruments and the complexity of marine samples. This research presents a novel analytical method using differential pulse anodic stripping voltammetry (DPASV) with a glassy carbon electrode (GCE) to determine mercury levels in sea sponges from the Niger Delta. Using a 2.36 M HCl + 2.4 M NaCl supporting electrolyte, -0.6 V deposition potential, and 300 s deposition time, average mercury levels were found to be 0.98 mg kg-1, 0.63 mg kg-1 and 0.42 mg kg-1 for Ibiotirem, Kaa and Samanga, respectively. The result showed that the Niger Delta is polluted, and remediation efforts are necessary. Furthermore, the DPASV method could be used for routine mercury monitoring as it is cost-effective, user-friendly, and highly sensitive.

20.
Med Mycol ; 2024 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-39327022

RESUMEN

Azole resistance has emerged as a new therapeutic challenge in patients with aspergillosis. Various resistance mutations are attributed to the widespread use of triazole-based fungicides in agriculture. This study explored the prevalence of azole-resistant Aspergillus fumigatus (ARAF) and other aspergilli in the Argentine environment. A collection of A. fumigatus and other aspergilli strains isolated from soil of growing crops, compost, corn, different animal feedstuffs, soybean and chickpea seeds were screened for azole resistance. No ARAF was detected in any of the environmental samples studied. However, five A. flavus, one A. ostianus, one A. niger and one A. tamarii recovered from soybean and chickpea seeds showed reduced susceptibility to medical azole antifungals (MAA). The susceptibility profiles of five A. flavus isolates, showing reduced susceptibility to demethylase inhibitors (DMIs), were compared with those of 10 isolates that exhibited susceptibility to MAA. A. flavus isolates that showed reduced MAA susceptibility exhibited different susceptibility profile to DMIs. Prothioconazole and tebuconazole were the only DMIs significantly less active against isolates with reduced susceptibility to MAA. Although no ARAF isolates were found in the samples analysed, other aspergilli with reduced susceptibility profile to MAA being also important human pathogens causing allergic, chronic and invasive aspergillosis, are present in the environment in Argentina. Although a definitive link between triazole-based fungicide use and isolation of azole-resistant human pathogenic aspergilli from agricultural fields in Argentina remains elusive, this study unequivocally highlights the magnitude of the environmental spread of azole resistance among other Aspergillus species.


This study intended to inform about the prevalence of Aspergillus species showing triazole resistance in the Argentinian environment. Since azole fungicides are used for crop protection, it was expected that azole resistance in this species with cross-resistance to medical azoles can occur.

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