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1.
Article in English | MEDLINE | ID: mdl-39271537

ABSTRACT

The production of keratinases was evaluated in submerged fermentation with Aspergillus niger and by pigs' swine hair in a batch bioreactor. Experimental planning was performed to assess the interaction between different variables. The enzyme extract produced was characterized at various pH and temperatures and subjected to enzyme concentration using a biphasic aqueous system and salt/solvent precipitation techniques. In addition, the substrate's potential in reducing hexavalent chromium from synthetic potassium dichromate effluent with an initial concentration of 20 mg L-1 of chromium was evaluated. The resulting enzyme extract showed 89 ± 2 U mL-1 of keratinase. The enzyme concentration resulted in a purification factor of 1.3, while sodium chloride/acetone and ammonium sulfate/acetone resulted in a purification factor of 1.9 and 1.4, respectively. Still using the residual substrate of swine hair from the fermentation, a 94% reduction of hexavalent chromium concentration occurred after 9 h of reaction. Thus, the study proved relevant for producing keratinases, with further environmental applicability and the possibility of concentrating the extract via low-cost processes.

2.
Article in English | MEDLINE | ID: mdl-39147449

ABSTRACT

Brazil is one of the world's largest consumers of pesticides. This intense use impacts the environment and exposes a wide range of individuals to pesticides, including rural workers who are occupationally exposed and rural residents who are environmentally exposed. We aimed to evaluate the effects of occupational exposure to pesticides on the health of rural workers and rural residents. We conducted an epidemiological study with 104 farmers and 23 rural residents of Casimiro de Abreu (Rio de Janeiro, Brazil). A comparison group (urban residents) comprised 103 residents of the urban area of the same city. We determined the activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) using a modified version of Ellman's method to evaluate exposure. In addition, we performed genotoxic and mutagenic analyses with the comet assay and the cytokinesis-block micronucleus (CBMN) assay. There was a reduction in cholinesterase activity, mainly BChE, in rural workers and rural residents compared with urban residents (p = 0.002). There was an increase in genotoxic effects in rural workers compared with urban residents (comet assay, p < 0.001; CBMN assay, p < 0.001). In addition, there was a greater chance of genotoxic changes in rural workers exposed to pesticides based on the comet assay (odds ratio [OR] 7.6, 95 % confidence interval [CI] 6.6-15.9) and the CBMN assay (OR 22.7, 95 % CI 10.3-49.9). We found that individuals occupationally exposed to pesticides are more likely to have genotoxic effects. These findings are useful for the development of programs to monitor populations exposed to genotoxic substances and allow the development of strategies for the prevention, control, and surveillance of effects that result from occupational and environmental exposures to pesticides.


Subject(s)
Butyrylcholinesterase , Comet Assay , DNA Damage , Micronucleus Tests , Occupational Exposure , Pesticides , Rural Population , Humans , Pesticides/toxicity , Brazil , Occupational Exposure/adverse effects , Adult , Male , Middle Aged , Butyrylcholinesterase/genetics , Female , DNA Damage/drug effects , Farmers , Acetylcholinesterase , Urban Population
3.
Porto Biomed J ; 9(4): 260, 2024.
Article in English | MEDLINE | ID: mdl-38993951

ABSTRACT

Background: Studies on agitation in internal medicine departments are scarce, especially regarding how doctors and nurses act in these situations. The objective of this study was to clarify how agitation is dealt with in these departments. Methods: This prospective observational study was performed in the internal medicine departments of four Portuguese hospitals. The researchers at each hospital contacted the nursing team that identifies patients who were agitated in the previous shifts. The researcher reviewed these patients' files, recording the research protocol's parameters. Results: During the study period, 331 patients were observed; 177 (54%) were female, and the median age was 80 years (19-99). Episodes of agitation occurred in 69 patients (21%); of them, 44 (64%) were female, and the median age was 84 years (31-98). In the first episode of agitation, the doctor on duty was called in 49 times (71%). These doctors prescribed a new medication for the crisis in 30 cases (43%). After the crisis, the assistant doctor recorded the episode in the patient file in 41 cases (59%). According to the medical notes, after the acute phase, in only 21 patients (30%), there was an attempt to clarify the cause of agitation. The prescription after the crisis was regular medication in 32 cases (46%), rescue medication in 27 (39%), and physical restraint in 9 (13%), isolated or in various combinations. Conclusion: This study suggests that there is room to improve how agitated patients are managed in internal medicine departments.

4.
Bioprocess Biosyst Eng ; 47(5): 651-663, 2024 May.
Article in English | MEDLINE | ID: mdl-38554182

ABSTRACT

During scaling of fermentations, choosing a bioreactor is fundamental to ensure the product's quality. This study aims to produce bioherbicides using Trichoderma koningiopsis fermentation, evaluating process parameters in an Airlift bioreactor. As a response, we quantified the production of enzymes involved in the bioherbicide activity (amylase, cellulase, laccase, lipase, and peroxidase). In addition, it evaluated the agronomic efficiency of the fermented extract optimized through tests that promoted soybean growth and nodulation, soybean seed germination, and in vitro phytopathogen control. As a result of optimizing the scaling bioprocess, it was possible to obtain an adequate fermentation condition, which, when applied to soybean seeds, had beneficial effects on their growth. It allowed the production of an enzyme cocktail. These results add a crucial biotechnological potential factor for the success of the optimized formulation in the Airlift bioreactor, in addition to presenting relevant results for the scientific community.


Subject(s)
Bioreactors , Glycine max , Trichoderma , Glycine max/metabolism , Glycine max/growth & development , Trichoderma/growth & development , Trichoderma/metabolism , Fermentation
5.
Cureus ; 16(2): e53853, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38465141

ABSTRACT

Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare clinical entity characterized by symmetrical tenosynovitis of both hands and ankles with pitting edema, negative rheumatoid factor (RF), absence of radiographic erosions, and excellent response to low-dose steroids. It is classically associated with elderly patients but may occur in younger patients, with only one case reported in the pediatric age. We report a case of RS3PE diagnosed in a pediatric patient.

7.
Digit Health ; 10: 20552076231223805, 2024.
Article in English | MEDLINE | ID: mdl-38222080

ABSTRACT

Introduction: Computer confidence and computer self-efficacy can impact an individual's perceived ease of use and usefulness of technology, ultimately determining adherence to digital healthcare services. However, few studies focus on assessing the impact of non-clinical factors on the efficacy and adherence to digital healthcare platforms. Objective: We aimed to analyse the role of non-clinical factors (i.e. computer confidence and computer self-efficacy) in the interaction experience (IX) and the feasibility of a digital neuropsychological platform called NeuroVRehab.PT in a group of older adults with varying levels of computer confidence. Methods: Eight older adults (70.63 ± 6.1 years) evaluated the platform, and data was collected using the Think-Aloud method and a semi-structured interview. Sessions were audio-recorded and analysed through an inductive-deductive informed Thematic Analysis protocol. This study was conducted according to the Consolidated Criteria for Reporting Qualitative Research guidelines. Results: Three main themes were identified (Interaction Experience, Digital Literacy, and Attitudes toward NeuroVRehab.PT). Computer anxiety and fear of making errors were not uncommon, even among older adults who perceive themselves as confident in technology use, and negatively impacted IX. Moreover, some game elements (e.g. three-star system, progression bar) were not intuitive to all participants, leading to misleading interpretations. On the other hand, human support and the platform's realism seemed to impact participants' IX positively. Conclusions: This study shed light on the barriers raised by non-clinical factors in adopting and using digital healthcare services by older adults. Furthermore, a critical analysis of the platform's features that promote user adoption is done, and suggestions for overcoming limitations are presented.

8.
Biomed Chromatogr ; 38(3): e5746, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37723598

ABSTRACT

The general population and workers are exposed to organophosphate insecticides, one of the leading chemical classes of pesticides used in rural and urban areas. This paper aims to conduct an integrative review of the most used analytical methods for identifying and quantifying dialkylphosphate-which are metabolites of organophosphate insecticides-in the urine of exposed workers, discussing their advantages, limitations and applicability. Searches utilized the PubMed, the Scientific Electronic Library Online and the Brazilian Digital Library of Theses and Dissertations databases between 2000 and 2021. Twenty-five studies were selected. The extraction methods most used were liquid-liquid extraction (LLE) (36%) and solid-phase extraction (SPE) (36%), with the SPE being more economical in terms of time and amount of solvents needed, and presenting the best percentage of recovery of analytes, when compared with LLE. Nineteen studies (76%) used the gas chromatography method of separation, and among these, 12 records (63%) indicated mass spectrometry used as a detection technology (analyzer). Studies demonstrate that dialkylphosphates are sensitive and representative exposure biomarkers for environmental and occupational organophosphate exposure.


Subject(s)
Insecticides , Pesticides , Humans , Insecticides/analysis , Gas Chromatography-Mass Spectrometry , Organophosphorus Compounds/analysis , Organophosphates/urine
10.
Porto Biomed J ; 8(6): e238, 2023.
Article in English | MEDLINE | ID: mdl-38093796

ABSTRACT

Introduction: Gastrostomies can be performed percutaneously by interventional radiology (PRG) or endoscopy (PEG). Methods: Retrospective analysis of patients with advanced cancer who underwent a gastrostomy in 2017 in an oncology center. Results: In 2017, 164 patients underwent gastrostomies, and 137 (84%) were male. The median age was 60 years (range: 38-91). The predominant Eastern Cooperative Oncology Group (ECOG) performance status stage was 1, with 73 (45%) patients. Head and neck cancer was the most common diagnosis, with 127 (77%) cases. The most frequent reason for performing a gastrostomy was dysphagia, 132 (81%). Most gastrostomies were PEG, 121 (74%), followed by PRG, 41 (25%), and surgery, 2 (1%). Early complications occurred in 86 (52%) patients, and the most frequent of them were local pain in 69 (80%) patients and minor local bleeding in 13 (15%). Late complications occurred in 90 (55%) patients, and the most frequent was also local pain in 57 (63%) patients, followed by local infection in 8 (9%), tube extrusion in 7 (8%), and stomal leakage in 7 (8%). In the multivariable analysis, the factors associated with survival were lymph node metastases and the ECOG performance status. Until June 30th, 2022, 123 (75%) patients had died, and 41 (25%) were still alive. Conclusion: Gastrostomies were performed predominantly in ECOG performance stage 1 patients with head and neck cancer and symptoms of dysphagia, and PEG was the most common procedure.

11.
Environ Monit Assess ; 196(1): 10, 2023 Dec 05.
Article in English | MEDLINE | ID: mdl-38049584

ABSTRACT

The general population and workers are exposed to organophosphate insecticides, one of the leading chemical classes of pesticides used in rural and urban areas, in the control of arboviruses and agriculture. These pesticides cause environmental/occupational exposure and associated risks to human and environmental health. The objective of this study was to carry out an integrative review of epidemiological studies that identified and quantified dialkylphosphate metabolites in the urine of exposed populations, focusing on the vector control workers, discussing the application and the results found. Searches utilized the Pubmed, Scielo, and the Brazilian Digital Library of Theses and Dissertations (BDTD) databases between 2000 and 2021. From the 194 selected studies, 75 (39%) were with children/adolescents, 48 (24%) with rural workers, 36 (19%) with the general population, 27 (14%) with pregnant women, and 9 (4%) with vector control workers. The total dialkylphosphate concentrations found in the occupationally exposed population were higher than in the general population. Studies demonstrate that dialkylphosphates are sensitive and representative exposure biomarkers for environmental and occupational organophosphate exposure. The work revealed a lack of studies with vector control workers and a lack of studies in developing countries.


Subject(s)
Insecticides , Occupational Exposure , Pesticides , Child , Humans , Female , Pregnancy , Adolescent , Environmental Monitoring , Organophosphorus Compounds , Environmental Exposure/analysis , Organophosphates
12.
Mod Rheumatol ; 2023 08 12.
Article in English | MEDLINE | ID: mdl-37572107

ABSTRACT

BACKGROUND: Pediatric uveitis poses challenges in diagnosis and treatment due to asymptomatic or oligosymptomatic presentations and high rates of intraocular complications. OBJECTIVES: This study aimed to characterize clinical manifestations and treatment approaches of pediatric uveitis patients in a northern Portuguese tertiary hospital. METHODOLOGY: A retrospective study was conducted involving forty-one patients diagnosed with uveitis between 2006 and 2021. All individuals identified by the Opthalmology department were referred to Pediatric Rheumatology outpatient clinic. Demographic, clinical, treatment, and intraocular complications data were collected. RESULTS: Of the patients, 78% had anterior uveitis, 17% had panuveitis, and 5% had intermediate uveitis. Uveitis associated with juvenile idiopathic arthritis was the most common cause (43.9%), predominantly in the oligoarticular, anti-nuclear antibody-positive subgroup. Complications were identified in 80.5% of the patients. Uveitis associated with JIA was diagnosed earlier (5,0 years (3,0-10,5) vs. 9,0 years (5,5-14,0), p=0,036), more frequently in asymptomatic patients (71% vs. 23%, p=0,010), had a more insidious installation (71% vs. 17%, p=0,004), and required more TNF inhibitor treatment (70% vs. 39%, p=0,027). CONCLUSION: The high rates of intraocular complications and systemic pathology association highlight the need for a combined approach of ophthalmology and pediatric rheumatology in the diagnosis and treatment of pediatric uveitis.

13.
Cureus ; 15(6): e39941, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37409194

ABSTRACT

Disseminated intravascular coagulation (DIC) is an acquired syndrome that can lead to catastrophic thrombosis and hemorrhage. In DIC, an uncontrolled release of pro-inflammatory mediators activates tissue factor-dependent coagulation. These changes cause endothelial dysfunction and increased depletion of platelets and clotting factors needed to control bleeding, which results in excessive bleeding. The clinical manifestations are microvascular thrombosis and hemorrhage, which cause severe organ dysfunction and worsening of organ failure. Its clinical management is challenging. Coronavirus disease 2019 (COVID-19) is characterized mainly by respiratory manifestations. In severe cases, however, systemic inflammatory response syndrome can develop with cytokine release that leads to coagulopathy and DIC. Among patients with COVID-19, this complication occurs rarely, leading to death in the majority of cases. We describe the case of a 67-year-old woman with asthma and class 1 obesity, hospitalized with respiratory insufficiency after diagnosis of COVID-19, in whom DIC developed with hemorrhagic manifestations on Day 4 of hospitalization. In spite of poor prognosis and multiple complications throughout the 87 days of hospitalization, including 62 days in the ICU, this patient survived.

14.
Plants (Basel) ; 12(14)2023 Jul 19.
Article in English | MEDLINE | ID: mdl-37514302

ABSTRACT

The literature is full of studies reporting environmental and health issues related to using traditional pesticides in food production and storage. Fortunately, alternatives have arisen in the last few decades, showing that organic agriculture is possible and economically feasible. And in this scenario, fungi may be helpful. In the natural environment, when associated with plants, these microorganisms offer plant-growth-promoting molecules, facilitate plant nutrient uptake, and antagonize phytopathogens. It is true that fungi can also be phytopathogenic, but even they can benefit agriculture in some way-since pathogenicity is species-specific, these fungi are shown to be useful against weeds (as bioherbicides). Finally, plant-associated yeasts and molds are natural biofactories, and the metabolites they produce while dwelling in leaves, flowers, roots, or the rhizosphere have the potential to be employed in different industrial activities. By addressing all these subjects, this manuscript comprehensively reviews the biotechnological uses of plant-associated fungi and, in addition, aims to sensitize academics, researchers, and investors to new alternatives for healthier and more environmentally friendly production processes.

15.
Inorg Chem ; 62(20): 7834-7842, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37156094

ABSTRACT

The incorporation of electroactive organic building blocks into coordination polymers (CPs) and metal-organic frameworks (MOFs) offers a promising approach for adding electronic functionalities such as redox activity, electrical conductivity, and luminescence to these materials. The incorporation of perylene moieties into CPs is, in particular, of great interest due to its potential to introduce both luminescence and redox properties. Herein, we present an innovative synthesis method for producing a family of highly crystalline and stable coordination polymers based on perylene-3,4,9,10-tetracarboxylate (PTC) and various transition metals (TMs = Co, Ni, and Zn) with an isostructural framework. The crystal structure of the PTC-TM CPs, obtained through powder X-ray diffraction and Rietveld refinement, provides valuable insights into the composition and organization of the building blocks within the CP. The perylene moieties are arranged in a herringbone pattern, with short distances between adjacent ligands, which contributes to the dense and highly organized framework of the material. The photophysical properties of PTC-Zn were thoroughly studied, revealing the presence of J-aggregation-based and monomer-like emission bands. These bands were experimentally identified, and their behavior was further understood through the use of quantum-chemical calculations. Solid-state cyclic voltammetry experiments on PTC-TMs showed that the perylene redox properties are maintained within the CP framework. This study presents a simple and effective approach for synthesizing highly stable and crystalline perylene-based CPs with tunable optical and electrochemical properties in the solid state.

16.
Cureus ; 15(2): e34851, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36923195

ABSTRACT

There is an unclear association between the syndrome of inappropriate antidiuretic hormone secretion (SIADH) and amyotrophic lateral sclerosis (ALS), with few reports in the literature. We report the case of an 80-year-old man admitted to our emergency room with asthenia, dysphonia, dysphagia, weight loss, and euvolemic hyponatremia, indicating a SIADH. Posteriorly, the patient also developed respiratory failure, which, in association with the previous clinical presentation, led to the diagnosis of ALS. During her permanence at the hospital, the hyponatremia improved with noninvasive positive-pressure ventilation, and the association between these two identities was made. This case also shows that patients with ALS commonly suffer from chronic respiratory failure and still have a reserved prognosis.

17.
Arq. Ciênc. Vet. Zool. UNIPAR (Online) ; 26(1cont): 45-58, jan.-jun. 2023.
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1433847

ABSTRACT

A Cannabis sativa é uma planta que apresenta vários benefícios terapêuticos para animais, como tratamento da dor neuropática, inflamatória e osteoartrose. A dor é bastante recorrente na rotina clínica, sendo importante seu manejo para que seja ofertada uma melhor qualidade e conforto de vida para o paciente. O estudo objetivou identificar, a partir de evidências científicas, as características da utilização medicinal do uso de Cannabis Sativa no tratamento da dor crônica no cão, utilizando um dos seus princípios ativos, canabidiol (CBD). Foi feito uma revisão bibliográfica onde foi realizada a busca de estudos experimentais e relatos de caso em bases de dados eletrônicos, sendo incluídas fontes contendo a utilização do CBD em animais, que abordaram controle da dor, assim como escore avaliativo da dor antes, durante e após o tratamento proposto. Após eleger e analisar 54 estudos percebe-se que na medicina veterinária o uso do canabidio é insuficiente, uma vez que o foco da maior parte dos estudos clínicos é voltado para medicina humana. Ainda assim, a utilização de CBD mostrou-se eficaz, confirmando uma nova alternativa para o controle da dor em animais.(AU)


Cannabis sativa is a plant that has several therapeutic benefits for animals, such as the treatment of neuropathic and inflammatory pain and osteoarthritis. Pain is quite recurrent in the clinical routine, and its management is important to offer a better quality and comfort of life for the patient. The study aimed to identify, based on scientific evidence, the characteristics of the medicinal use of Cannabis Sativa in the treatment of chronic pain in dogs, using one of its active principles, cannabidiol (CBD). A bibliographical review was carried out in which experimental studies and case reports were searched in electronic databases, including sources containing the use of CBD in animals, which addressed pain control, as well as pain assessment score before, during and after the proposed treatment. After choosing and analyzing 54 studies, it is clear that in veterinary medicine the use of CBD is few, and the focus of clinical studies is on human medicine. The use of CBD proved to be effective, thus confirming a new alternative for pain control in animals.(AU)


El cannabis sativa es una planta que tiene varios beneficios terapéuticos para los animales, como el tratamiento del dolor neuropático e inflamatorio y la osteoartritis. El dolor es bastante recurrente en la rutina clínica, y su manejo es importante para ofrecer una mejor calidad y comodidad de vida al paciente. El estudio tuvo como objetivo identificar, con base en la evidencia científica, las características del uso medicinal de Cannabis Sativa en el tratamiento del dolor crónico en perros, utilizando uno de sus principios activos, el cannabidiol (CBD). Se realizó una revisión bibliográfica en la que se buscaron estudios experimentales y reportes de casos en bases de datos electrónicas, incluyendo fuentes que contengan el uso de CBD en animales, que abordaran el control del dolor, así como la puntuación de evaluación del dolor antes, durante y después del tratamiento propuesto. Después de elegir y analizar 54 estudios, queda claro que en medicina veterinaria el uso de cannabidio es insuficiente, ya que el foco de la mayoría de los estudios clínicos está en la medicina humana. Aun así, el uso de CBD demostró ser efectivo, confirmando una nueva alternativa para el control del dolor en animales.(AU)


Subject(s)
Animals , Osteoarthritis/drug therapy , Dogs , Chronic Pain/therapy , Marijuana Use/adverse effects
18.
J Fungi (Basel) ; 8(10)2022 Sep 20.
Article in English | MEDLINE | ID: mdl-36294549

ABSTRACT

The importance of insects for angiosperm pollination is widely recognized. In fact, approximately 90% of all plant species benefit from animal-mediated pollination. However, only recently, a third part player in this story has been properly acknowledged. Microorganisms inhabiting floral nectar, among which yeasts have a prominent role, can ferment glucose, fructose, sucrose, and/or other carbon sources in this habitat. As a result of their metabolism, nectar yeasts produce diverse volatile organic compounds (VOCs) and other valuable metabolites. Notably, some VOCs of yeast origin can influence insects' foraging behavior, e.g., by attracting them to flowers (although repelling effects have also been reported). Moreover, when insects feed on nectar, they also ingest yeast cells, which provide them with nutrients and protect them from pathogenic microorganisms. In return, insects serve yeasts as transportation and a safer habitat during winter when floral nectar is absent. From the plant's point of view, the result is flowers being pollinated. From humanity's perspective, this ecological relationship may also be highly profitable. Therefore, prospecting nectar-inhabiting yeasts for VOC production is of major biotechnological interest. Substances such as acetaldehyde, ethyl acetate, ethyl butyrate, and isobutanol have been reported in yeast volatomes, and they account for a global market of approximately USD 15 billion. In this scenario, the present review addresses the ecological, environmental, and biotechnological outlooks of this three-party mutualism, aiming to encourage researchers worldwide to dig into this field.

19.
Asia Pac Allergy ; 12(3): e29, 2022 Jul.
Article in English | MEDLINE | ID: mdl-35966154

ABSTRACT

Background: Systemic autoinflammatory diseases (SAID) are monogenic and polygenic inherited conditions characterized by dysregulation of the innate immune system. Objective: We aimed to characterize the clinical features of patients with SAID. Methods: This study was a retrospective chart review on the clinical and genetic features of the pediatric population with SAID observed from 1998 to 2020 in our center. Results: A total of 54 patients were evaluated: 18 with periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome; 16 with Behçet disease; 13 with systemic juvenile idiopathic arthritis; 4 with syndrome of undifferentiated recurrent fever; 1 with cryopyrin associated periodic syndrome; 1 with chronic nonbacterial osteomyelitis; and 1 with Muckle-Wells syndrome. Conclusion: The analysis of clinical features of our patients are similar to other studies. Our goal was to aware the medical community to early recognize and treat SAID to improve quality of life of pediatric patients.

20.
World J Microbiol Biotechnol ; 38(2): 35, 2022 Jan 06.
Article in English | MEDLINE | ID: mdl-34989919

ABSTRACT

Aiming to broaden the base of knowledge about wild yeasts, four new indigenous strains were isolated from corn residues, and phylogenetic-tree assemblings on ITS and LSU regions indicated they belong to Meyerozyma caribbica. Yeasts were cultivated under full- and micro-aerobiosis, starting with low or high cell-density inoculum, in synthetic medium or corn hydrolysate containing glucose and/or xylose. Cells were able to assimilate both monosaccharides, albeit by different metabolic routes (fermentative or respiratory). They grew faster in glucose, with lag phases ~ 10 h shorter than in xylose. The hexose exhaustion occurred between 24 and 34 h, while xylose was entirely consumed in the last few hours of cultivation (44-48 h). In batch fermentation in synthetic medium with high cell density, under full-aerobiosis, 18-20 g glucose l-1 were exhausted in 4-6 h, with a production of 6.5-7.0 g ethanol l-1. In the xylose medium, cells needed > 12 h to consume the carbohydrate, and instead of ethanol, cells released 4.4-6.4 g l-1 xylitol. Under micro-aerobiosis, yeasts were unable to assimilate xylose, and glucose was more slowly consumed, although the ethanol yield was the theoretical maximum. When inoculated into the hydrolysate, cells needed 4-6 h to deplete glucose, and xylose had a maximum consumption of 57%. Considering that the hydrolysate contained ~ 3 g l-1 acetic acid, it probably has impaired sugar metabolism. Thus, this study increases the fund of knowledge regarding indigenous yeasts and reveals the biotechnological potential of these strains.


Subject(s)
Glucose/metabolism , Saccharomycetales/metabolism , Xylose/metabolism , Zea mays/microbiology , Acetic Acid , Aerobiosis , Biomass , Culture Media/chemistry , Fermentation , Lignin , Phylogeny , Saccharomycetales/classification , Saccharomycetales/genetics , Saccharomycetales/isolation & purification , Xylitol/biosynthesis
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