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1.
Int J Biol Macromol ; 222(Pt A): 65-76, 2022 Dec 01.
Article in English | MEDLINE | ID: mdl-36108753

ABSTRACT

The objective of this work was to evaluate the effects of enzymatic hydrolysis on digestibility and morphological and structural properties of hydrothermally pre-treated (HPT) red rice starch. The pre-treatments were performed in autoclave and cooking for the modification of rice grains and native starch. In vitro starch digestibility was performed consecutively and semi-simultaneously using α-amylase and amyloglucosidase. A first-order mathematical model was used to adjust the hydrolysis kinetic data, which made it possible to calculate the surface area, hydrolysis index, and glycemic index of the starch. Scanning electron microscopy images (SEM), Fourier transform infrared (FTIR) spectra and X-ray diffraction (XRD) were also performed to investigate the characteristics of the post-hydrolysis starch samples. The autoclaved starch HSS-A3, which was subjected to 121 °C/1.08 bar for 10 min, showed the highest in vitro digestibility values (80.08 %). Both starch samples showed increase of particle size and enzymatic digestibility after HPT. FTIR spectra of the starch samples showed that there was no appearance of new functional groups. However, XRD evidenced that HPT changed the intensity of the peaks and the type of crystallinity was changed for autoclaved starch (A3) from type A to Vh, with crystallinity ranging from 21.71 % to 26.42 %. The semi-simultaneous approach showed more advantages due to the highest in vitro digestibility as well as reducing the processing time and use of reagents.


Subject(s)
Oryza , Starch , Starch/chemistry , Oryza/chemistry , Hydrolysis , Cooking , alpha-Amylases , Digestion
2.
Prep Biochem Biotechnol ; 51(7): 714-722, 2021.
Article in English | MEDLINE | ID: mdl-33287624

ABSTRACT

The present study aimed to evaluate the lactose hydrolysis conditions from "coalho" cheese whey using ß-galactosidase (ß-gal) produced by Kluyveromyces lactis immobilized with sodium alginate. Three sodium alginate-based immobilization systems were evaluated (0.5, 0.7, and 1% w/v) for maximizing the immobilization yield (Y), efficiency (EM), and recovered activity (ar). The lactose hydrolysis capacity of the immobilized form of ß-gal was determined, and simulated environments were used to assess the preservation of the immobilized enzyme in the gastrointestinal tract. The results showed that ß-gal immobilization with 1% (w/v) sodium alginate presented the best results (EM of 66%, Y of 41%, and ar of 65%). The immobilization system maintained the highest pH stability in the range between 5.0 and 7.0, with the highest relative activity obtained under pH 5 conditions. The temperature stability was also favored by immobilization at 50 °C for 30 min was obtained a relative activity of 180.0 ± 1.37%. In 6 h, the immobilized ß-gal was able to hydrolyze 46% of the initial lactose content. For the gastrointestinal simulations, around 40% of the activity was preserved after 2 h. Overall, the results described here are promising for the industrial applications of ß-galactosidase from K. lactis.


Subject(s)
Alginates/chemistry , Enzymes, Immobilized/chemistry , Fungal Proteins/chemistry , Kluyveromyces/enzymology , Lactose/chemistry , beta-Galactosidase/chemistry , Enzyme Stability , Hot Temperature , Hydrogen-Ion Concentration , Hydrolysis
3.
Food Chem ; 337: 127771, 2021 Feb 01.
Article in English | MEDLINE | ID: mdl-32777564

ABSTRACT

Faveleira (Cnidoscolus quercifolius) is an emerging Brazilian plant, with seeds rich in edible oil. This study investigates physicochemical properties, chemical composition, thermal and oxidative stability, in vitro and in vivo toxicity, antioxidant, antinociceptive and anti-inflammatory activities of faveleira seed oil. It was observed that the oil has low acidity, value of peroxide, chlorophyll, carotenoids, ß-carotene and high concentrations of unsaturated fatty acids. In addition to presenting thermal and oxidative stability and high total phenolic content, with vanillin, eugenol and quercetin were predominating. The oil showed no toxicity in vitro and in vivo, and presented antioxidant, anti-inflammatory and antinociceptive activities. These findings provide relevant and appropriate conditions for processing of faveleira seed oil as functional food.


Subject(s)
Euphorbiaceae/metabolism , Plant Oils/chemistry , Analgesics/chemistry , Analgesics/pharmacology , Analgesics/therapeutic use , Animals , Antioxidants/chemistry , Brazil , Carotenoids/analysis , Cell Survival/drug effects , Chlorophyll/analysis , Euphorbiaceae/chemistry , Fatty Acids/analysis , Male , Mice , Pain/chemically induced , Pain/prevention & control , Phenols/analysis , Plant Oils/pharmacology , Plant Oils/therapeutic use , RAW 264.7 Cells , Seeds/chemistry , Seeds/metabolism
4.
Prep Biochem Biotechnol ; 51(3): 300-308, 2021.
Article in English | MEDLINE | ID: mdl-32914662

ABSTRACT

The present study evaluated the surfactin production by Bacillus subtilis UFPEDA 438 using sugarcane molasses as a substrate. The effects of the cultivation conditions (temperature, agitation and aeration ratio) on the biosurfactant production and kinetic parameters were investigated. Characteristics of the biosurfactant were obtained after analyses of the emulsification index (EI) and critical micellar concentration (CMC) of the fermentation broth. The results showed that in relation to the product its formation kinetics is strongly affected by operational conditions. It was also observed that surfactin production can be partially dependent or fully independent on microbial growth. The maximum values of surfactin concentration (199.45 ± 0.13 mg/L) and productivity (8,187 mg/L.h) were obtained in the culture under cultivation time of 24 h, temperature of 36 °C, agitation of 100 rpm and aeration ratio of 0.4. Under optimal conditions, the fermentation broth achieved good emulsification capacity (EI >40%) and CMC value of 20.73 mg/L. The results revealed that Bacillus subtilis UFPEDA 438 is a good producer of biosurfactant and that sugarcane molasses is a viable substrate for the production of surfactin.


Subject(s)
Bacillus subtilis/metabolism , Biotechnology/methods , Carbon/chemistry , Molasses , Surface-Active Agents/chemistry , Bacillus/metabolism , Biomass , Culture Media/pharmacology , Fermentation , Hydrogen-Ion Concentration , Kinetics , Micelles , Saccharum , Temperature
5.
BMC Biotechnol ; 20(1): 55, 2020 10 16.
Article in English | MEDLINE | ID: mdl-33066751

ABSTRACT

BACKGROUND: Buriti oil presents numerous health benefits, but due to its lipophilic nature and high oxidation, it is impossible to incorporate it into aqueous food matrices. Thus, the present study evaluated whether powder nanoparticles based on porcine gelatin (OPG) and in combination with sodium alginate (OAG) containing buriti oil obtained by O/W emulsification followed by freeze-drying enabled water dispersibility and preserved or increased the antimicrobial activity of the oil. RESULTS: OPG presented spherical shape, smooth surface, smaller particle size and polydispersity index [51.0 (6.07) nm and 0.40 (0.05)], and better chemical interaction between the nonpolar amino acids and the hydrophobic oil chain. OPG also presented a higher dispersibility percentage [85.62% (7.82)] than OAG [50.19% (7.24)] (p < 0.05), and significantly increased the antimicrobial activity of the oil by 59, 62, and 43% for Pseudomonas aeruginosa, Klebsiella pneumonia, and Staphylococcus aureus, respectively. CONCLUSIONS: Thus, nanoencapsulation in gelatin is a promising strategy to increase the potential to use buriti oil in foods.


Subject(s)
Anti-Infective Agents/pharmacology , Arecaceae/chemistry , Gelatin/chemistry , Gelatin/pharmacology , Nanoparticles/chemistry , Water/chemistry , Amino Acids , Animals , Anti-Infective Agents/chemistry , Carotenoids , Fatty Acids , Hydrophobic and Hydrophilic Interactions , Hydroxybenzoates/analysis , Microbial Sensitivity Tests , Particle Size , Plant Extracts/pharmacology , Plant Oils , Swine
6.
J Environ Manage ; 234: 44-51, 2019 Mar 15.
Article in English | MEDLINE | ID: mdl-30599329

ABSTRACT

Ethanol production by simultaneous saccharification and fermentation (SSF) using sugarcane bagasse as substrate was developed using batch and fed-batch mode. Acid, alkali, hydrothermal and hydrogen peroxide pretreatments to the sugarcane bagasse were tested. Experiments were carried out to optimize the enzyme load of cellulases and ß-glucosidase. Four strains, two of Saccharomyces cerevisiae and two of Kluyveromyces marxianus yeast species were evaluate using SSF to produce ethanol. A kinetic study in bioreactor was carried out to optimize the SSF. The batch process was optimized using 1.0 g/L of inoculum, 15.0 FPU/g cellulose of cellulases and 6.0% of initial cellulose reaching 92.0% of theoretical ethanol yield after 18 h using the bagasse pretreate by acid-alkali and S. cerevisiae PE-2. The fed-batch process with enzyme load three times lower than that was used in batch process, obtained 88% of theoretical ethanol yield in 40 h. Therefore, the use of the lignocellulosic biomass (sugarcane bagasse) for producing a biofuel (ethanol) reduces the need for oil and is an environmental-friendly process.


Subject(s)
Saccharum , Cellulose , Ethanol , Fermentation , Hydrolysis , Saccharomyces cerevisiae
7.
Rev Inst Med Trop Sao Paulo ; 60: e75, 2018 Nov 14.
Article in English | MEDLINE | ID: mdl-30462798

ABSTRACT

Coccidioidomycosis is a fungal infection caused by Coccidioides immitis or Coccidioides posadasii. These fungi are known to thrive in desert climate. Fungi produce infectious arthroconidia in soil, they are aerosolized in the air and when inhaled by humans, usually cause infections such as pneumonia. The first cases of coccidioidomycosis in Brazil were reported in 1978. Since then, there have been other reports mainly from desert regions of Northeastern Brazil. The present report describes three cases of coccidioidomycosis on male farmers from Serra Talhada county, Pernambuco State, who developed pneumonia and were subsequently diagnosed with pulmonary coccidioidomycosis. These three farmers were successfully treated with oral fluconazole. They reported having hunted armadillos in a rural and arid area of Pernambuco State. Armadillos are known to be carriers of Coccidioides. This is the first report of infection caused by Coccidioides in Pernambuco State, Brazil.


Subject(s)
Coccidioidomycosis/diagnosis , Lung Diseases, Fungal/diagnosis , Adult , Aged , Animals , Antifungal Agents/therapeutic use , Armadillos/microbiology , Coccidioidomycosis/drug therapy , Coccidioidomycosis/transmission , Fluconazole/therapeutic use , Humans , Lung Diseases, Fungal/drug therapy , Lung Diseases, Fungal/transmission , Male
8.
Medicina (Ribeiräo Preto) ; 50(5): 317-321, set.-out. 2017. ilus
Article in English | LILACS | ID: biblio-910559

ABSTRACT

Study design: case report. Case report: Man, 42 years old, diagnosed with aids two years ago, had developed enlarging in abdominal volume six months from admission. Computed tomography imaging showed free liquid in peritoneal cavity and increased retroperitoneal and mesenteric lymph nodes, besides splenomegaly. Ascitic fluid had milky appearance and high triglycerides levels. Hodgkin's lymphoma (mixed cellularity) was confirmed by histopathological analysis of a video-laparoscopic lymph node biopsy, Ann Arbor IIIS staging. Chemotherapy and continuation of highly active antiretroviral therapy resulted in weight gain and reduction of abdominal volume. Chylous ascites is a rare condition, which has a vast differential diagnosis. Discussion: In our review, the majority (15/18, 83%) of chylous ascites in HIV/aids-patients are due to infectious causes (mainly Mycobacterium avium complex and tuberculosis infection), in highly immunocompromised patients (mean TCD4=87cell/mL). To the best of our knowledge, this is the first case of chylous ascites secondary to Hodgkin's lymphoma in a patient with aids. (AU)


Tipo de estudo: relato de caso. Relato de caso: Homem, 42 anos, diagnosticado com aids há dois anos, desenvolveu aumento de volume abdominal há seis meses da admissão. Tomografia computadorizada mostrou líquido livre na cavidade peritoneal, além de linfonodos mesentéricos e esplenomegalia. O líquido ascítico tinha aspecto leitoso e alto nível de triglicerídeos. Após amplo diagnóstico diferencial, diagnosticamos linfoma de Hodgkin tipo celularidade mista por biópsia linfonodal via videolaparoscópica, Ann Arbor IIIS. Quimioterapia e continuação da terapia antirretroviral de alta potência resultaram em ganho de peso e redução do volume abdominal. Ascite quilosa é uma entidade rara, que possui vários diagnósticos diferenciais. Discussão: Em nossa revisão, a maioria (15/18, 83%) dos casos de ascite quilosa em paciente com HIV/aids deveu-se a causa infecciosa (especialmente pelo Mycobacterium avium complex e tuberculose), em pacientes gravemente imunocomprometidos (linfócitos T-CD4 médio=84células/mm3). Até onde sabemos, este é o primeiro caso de ascite quilosa secundária a linfoma de Hodgkin em paciente com aids. (AU)


Subject(s)
Humans , Male , Adult , Acquired Immunodeficiency Syndrome , Chylous Ascites , Hodgkin Disease , Lymphoma , Lymphoma, AIDS-Related , Venous Thrombosis
10.
Bioresour Technol ; 237: 20-26, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28411051

ABSTRACT

This work investigated the influence of chemical (Triton X-100) and biological surfactant preparation (rhamnolipids) in coconut husk hydrolysis that was subjected to pretreatment with acid-alkali or alkaline hydrogen peroxide. The natural and pretreated biomass was characterized using the National Renewable Energy Laboratory protocol analysis as well as X-ray diffraction and scanning electron microscopy. The results demonstrated that in terms of the total reducing sugars, there was no significant difference between the hydrolysis using Triton X-100 and rhamnolipids, regardless of the pretreatment. A cellulosic conversion value as high as 33.0% was obtained in experiments with rhamnolipids. The coconut husk was observed to be a potential biomass that could produce second generation ethanol, and the rhamnolipid preparation can be used to support for the enzymatic hydrolysis, enhancing the advantage of cellulose conversion into glucose over chemical surfactants because it is an environmentally friendly approach.


Subject(s)
Cocos , Glycolipids , Hydrolysis , Pseudomonas aeruginosa , Biomass , Cellulose
11.
Article in English | MEDLINE | ID: mdl-27839666

ABSTRACT

In this study, a general rate model was applied to the entire process of expanded bed adsorption chromatography (EBAC) for the chitosanases purification protocol from unclarified fermentation broth produced by Paenibacillus ehimensis using the anionic adsorbent Streamline® DEAE. For the experiments performed using the expanded bed, a homemade column (2.6cm×30.0cm) was specially designed. The proposed model predicted the entire EBA process adequately, giving R2 values higher than 0.85 and χ2 as low as 0.351 for the elution step. Using the validated model, a 33 factorial design was used to investigate other non-tested conditions as input. It was observed that the superficial velocity during loading and washing steps, as well as the settled bed height, has a strong positive effect on the F objective function used to evaluate the production of the purified chitosanases.


Subject(s)
Chromatography, Ion Exchange/methods , Glycoside Hydrolases/isolation & purification , Models, Chemical , Paenibacillus/enzymology , Adsorption , Fermentation , Glycoside Hydrolases/analysis
12.
Int J Biol Macromol ; 82: 291-8, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26433174

ABSTRACT

A chitosanase-producing strain was isolated and identified as Bacillus cereus C-01. The purification and characterization of two chitosanases were studied. The purification assay was accomplished by ion exchange expanded-bed chromatography. Experiments were carried out in the presence and in the absence of cells through different expansion degree to evaluate the process performance. The adsorption experiments demonstrated that the biomass does not affect substantially the adsorption capacity of the matrix. The enzyme bound to the resin with the same extent using clarified and unclarified broth (0.32 and 0.30 U/g adsorbent, respectively). The fraction recovered exhibited 31% of the yield with a 1.26-fold increase on the specific activity concerned to the initial broth. Two chitosanases from different elution steps were recovery. Chit A and Chit B were stable at 30-60°C, pH 5.5-8.0 and 5.5-7.5, respectively. The highest activity was found at 55°C, pH 5.5 to Chit A and 50°C, pH 6.5 to Chit B. The ions Cu(2+), Fe(2+) and Zn(2+) indicated inhibitory effect on chitosanases activities that were significantly activated by Mn(2+). The methodology applied in this study enables the partial purification of a stable chitosanase using a feedstock without any pre-treatment using a single-step purification.


Subject(s)
Bacillus cereus/enzymology , Chromatography/methods , Glycoside Hydrolases/chemistry , Glycoside Hydrolases/isolation & purification , Enzyme Activation , Hydrogen-Ion Concentration , Ions/chemistry , Temperature
13.
J Sep Sci ; 39(4): 709-16, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26638991

ABSTRACT

This study presents a system for expanded bed adsorption for the purification of chitosanase from broth extract in a single step. A chitosanase-producing strain was isolated and identified as Bacillus cereus C-01 and used to produce chitosanases. The expanded bed adsorption conditions for chitosanase purification were optimized statistically using STREAMLINE(TM) DEAE and a homemade column (2.6 × 30.0 cm). Dependent variables were defined by the quality criteria purification factor (P) and enzyme yield to optimize the chromatographic process. Statistical analyses showed that the optimum conditions for the maximum P were 150 cm/h load flow velocity, 6.0 cm settled bed height, and 7.36 cm distributor height. Distributor height had a strong influence on the process, considerably affecting both the P and enzyme yield. Optimizing the purification variables resulted in an approximately 3.66-fold increase in the P compared with the value under nonoptimized conditions. This system is promising for the recovery of chitosanase from B. cereus C-01 and is economically viable because it promotes the reduction steps.


Subject(s)
Bacillus cereus/enzymology , Glycoside Hydrolases/isolation & purification , Adsorption , Buffers , Chitosan/chemistry , Chromatography/methods , Ethanolamines , Glycoside Hydrolases/chemistry , Hydrodynamics , Hydrogen-Ion Concentration , Industrial Microbiology/methods , Ligands , Molecular Weight , Regression Analysis
14.
Article in English | MEDLINE | ID: mdl-25703945

ABSTRACT

Visceral leishmaniasis, a disease caused by Leishmania infantum chagasi, represents a major public health problem in many areas of the world. However, there is currently no vaccine for human use. The aim of this work was to purify the 503 antigen of Leishmania i. chagasi directly from unclarified Escherichia coli feedstock through expanded bed adsorption (EBA) chromatography. Batch experiments were performed to optimize the adsorption and elution conditions of the antigen onto a STREAMLINE Chelating resin using two central composite rotatable designs (CCRD). The results showed that the optimal binding conditions of the 503 antigen were pH 8.0 in the presence of 2.4 M NaCl. For the elution of the target protein, the optimized conditions included the presence of 600.0 mM imidazole. The adsorption isothermal data of the 503 antigen were fitted to the Langmuir adsorption isotherm. The EBA experiment successfully recovered 59.2% of the 503 antigen from the unclarified E. coli homogenate with a purification factor of 6.0.


Subject(s)
Antigens, Protozoan/isolation & purification , Chromatography, Affinity/methods , Leishmania infantum , Recombinant Proteins/isolation & purification , Adsorption , Antigens, Protozoan/chemistry , Escherichia coli/metabolism , Linear Models , Recombinant Proteins/chemistry
15.
Rev. Inst. Med. Trop. Säo Paulo ; 55(6): 425-428, Nov-Dec/2013. tab
Article in English | LILACS | ID: lil-690343

ABSTRACT

SUMMARY Report of a 45-year-old male farmer, a resident in the forest zone of Pernambuco, who was diagnosed with human immunodeficiency virus (HIV) in 1999 and treated using antiretroviral (ARV) drugs. In 2005, the first episode of visceral leishmaniasis (VL), as assessed by parasitological diagnosis of bone marrow aspirate, was recorded. When admitted to the hospital, the patient presented fever, hepatosplenomegaly, weight loss, and diarrhea. Since then, six additional episodes of VL occurred, with a frequency rate of one per year (2005-2012, except in 2008). In 2011, the patient presented a disseminated skin lesion caused by the amastigotes of Leishmania, as identified by histopathological assessment of skin biopsy samples. In 2005, he was treated with N-methyl-glucamine-antimony and amphotericin B deoxycholate. However, since 2006 because of a reported toxicity, the drug of choice was liposomal amphotericin B. As recommended by the Ministry of Health, this report emphasizes the need for HIV patients living in VL endemic areas to include this parasitosis in their follow-up protocol, particularly after the first infection of VL. .


RESUMO Relato de caso de paciente masculino de 45 anos, agricultor, residente na zona da mata do Estado de Pernambuco, diagnosticado com HIV em 1999 e em uso de ARV. Em 2005 foi registrada a primeira ocorrência de LV através do diagnóstico parasitológico a partir do aspirado da medula óssea. À admissão no hospital apresentava-se com febre, hepatoesplenomegalia, perda de peso e diarréia. Desde então houve a ocorrência de mais sete episódios de LV, tendo ocorrido em media, um evento a cada ano (2005-2012 exceto em 2008). O paciente apresentou, em 2011, um quadro cutâneo disseminado, sendo realizada biopsia de pele que evidenciou formas amastigotas de Leishmania no exame histopatológico. Em 2005, o tratamento foi realizado com antimoniato de N-metil-glucamina e anfotericina B desoxicolato, mas desde 2006, devido à toxicidade, o medicamento de escolha foi a anfotericina B lipossomal. Como recomendado pelo Ministério da Saúde, esse relato reforça a necessidade de que os casos de HIV residentes em área endêmica de LV deverão ter inserido em seu protocolo de acompanhamento essa parasitose, principalmente após o primeiro episódio. .


Subject(s)
Humans , Male , Middle Aged , AIDS-Related Opportunistic Infections/diagnosis , Leishmaniasis, Visceral/diagnosis , AIDS-Related Opportunistic Infections/parasitology , Recurrence
16.
Rev Inst Med Trop Sao Paulo ; 55(6): 425-8, 2013.
Article in English | MEDLINE | ID: mdl-24213197

ABSTRACT

Report of a 45-year-old male farmer, a resident in the forest zone of Pernambuco, who was diagnosed with human immunodeficiency virus (HIV) in 1999 and treated using antiretroviral (ARV) drugs. In 2005, the first episode of visceral leishmaniasis (VL), as assessed by parasitological diagnosis of bone marrow aspirate, was recorded. When admitted to the hospital, the patient presented fever, hepatosplenomegaly, weight loss, and diarrhea. Since then, six additional episodes of VL occurred, with a frequency rate of one per year (2005-2012, except in 2008). In 2011, the patient presented a disseminated skin lesion caused by the amastigotes of Leishmania, as identified by histopathological assessment of skin biopsy samples. In 2005, he was treated with N-methyl-glucamine-antimony and amphotericin B deoxycholate. However, since 2006 because of a reported toxicity, the drug of choice was liposomal amphotericin B. As recommended by the Ministry of Health, this report emphasizes the need for HIV patients living in VL endemic areas to include this parasitosis in their follow-up protocol, particularly after the first infection of VL.


Subject(s)
AIDS-Related Opportunistic Infections/diagnosis , Leishmaniasis, Visceral/diagnosis , AIDS-Related Opportunistic Infections/parasitology , Humans , Male , Middle Aged , Recurrence
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