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1.
J Dairy Sci ; 100(9): 6997-7006, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28734600

ABSTRACT

Marajó cheese made with raw buffalo milk in the Amazon region of Brazil can be considered a good source of wild lactic acid bacteria strains with unexplored and promising characteristics. The aim of this study was to develop a potential probiotic starter culture for industrial applications using freeze drying and spray drying. A decrease in the survival rates of freeze-dried samples compared with spray-dried samples was noted. The spray-dried cultures remained approximately 109 cfu·g-1, whereas the freeze-dried samples showed 107 cfu·g-1 after 60 d of storage at 4°C. All of the spray-dried samples showed a greater ability to decrease the pH in 10% skim milk over 24 h compared with the freeze-dried samples. The spray-dried samples showed a greater resistance to acidic conditions and to the presence of bile salts. In addition, under heat stress conditions, reduction was under 2 log cycles in all samples. Although the survival rate was similar among the evaluated samples after drying, the technological performance for skim milk showed some differences. This study may direct further investigations into how to preserve lactic acid bacteria probiotics to produce spray-dried starters that have a high number of viable cells that can then be used for industrial applications in a cost-effective way.


Subject(s)
Cheese/microbiology , Dairying/methods , Freeze Drying/methods , Probiotics , Aerosols , Animals , Brazil , Buffaloes , Milk
2.
Immunol Lett ; 262: 7-17, 2023 10.
Article in English | MEDLINE | ID: mdl-37634711

ABSTRACT

This study was designed to characterize mice bone marrow (BM) and bone marrow-derived dendritic cells (BMDC) and to compare the surface markers expression and inflammatory cytokine liberation in response to LPS and Bothrops jararacussu venom (BjV) stimulation. Typical morphology was observed in BM and BMDCs from the 4th up to the 8th day of culture using recombinant mouse GM-CSF and IL-4. A high basal level of MHC-II, CD1d, CD83, CD11c, CD80, and low CD86 was expressed by BM cells. After stimulation with GM-CSF/IL-4 for BMDCs differentiation, the BM cells differentiated into BMDCs presented MHC-II, CD1d, CD83, CD11c, CD86, and CD80 expression on the 4th - 8th day accompanied with high levels of TNF-α liberated. The difference between the surface markers' expression was observed in this time course in which CD1d, CD11c, and CD80 remained in high levels of expression, while MHC-II and CD83 showed moderate expression during the differentiation period. Also, cytokines liberation was monitored over the period of the BMDCs culture, and on the 6th day, low levels of IL-6 and IL-1ß were found, while high levels of TNF-α on the 4th and 8th days, both of which contributed to the maturity of the BMDCs. Maturation of DCs with LPS showed significant upregulation of surface markers (MHC-II, CD1d, CD83, CD86, CD80) and pro-inflammatory cytokines (IL-1ß, IL-6, TNF-α) liberation. On the other hand, BjV induced a decrease in CD1d, CD11c, CD83, and CD86 expression in mature BMDCs which was not observed when LPS was used to stimulate BMDCs which probably induces impairment in T-cell activation.


Subject(s)
Granulocyte-Macrophage Colony-Stimulating Factor , Tumor Necrosis Factor-alpha , Animals , Mice , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Bone Marrow , Interleukin-4 , Interleukin-6 , Lipopolysaccharides , Snake Venoms , Cytokines , Dendritic Cells
3.
Int J Immunogenet ; 38(3): 225-31, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21324097

ABSTRACT

FcγRIIA binding to IgG subclasses with different levels of affinity is influenced by the polymorphism in the gene that encodes this receptor. The substitution of arginine (R) for histidine (H) in the 131 position defines three allelic patterns, H/H, R/R, and H/R, resulting in FcγRIIA-H/H131 affinity for IgG2 and higher affinity for IgG3 subclasses. Studies have shown the importance of genetic host factors in leishmaniasis and participation of FcγRs on the macrophage infection by amastigote forms and in the immune response to Leishmania sp. We analysed the influence of allelic diversity patterns of the receptor FcγRIIA on American tegumentary leishmaniasis (ATL). FcγRIIA-H/R131 polymorphism was determined by PCR followed by an allele-specific enzymatic digestion in 88 individuals with ATL and 98 healthy volunteer blood donors (control group). The genotypic and allelic distributions of FcγRIIA-H/R131 were similar among the studied groups as well in mild and severe clinical forms of ATL. Our results suggest no association between this allelic polymorphism and susceptibility or resistance to ATL, neither influencing the development of different clinical forms of this illness.


Subject(s)
Leishmaniasis, Cutaneous/genetics , Polymorphism, Genetic , Receptors, IgG/genetics , Adolescent , Adult , Aged , Alleles , Case-Control Studies , Child , Female , Gene Frequency/genetics , Genotype , Humans , Male , Middle Aged , Young Adult
4.
Am J Med Genet B Neuropsychiatr Genet ; 147B(1): 114-6, 2008 Jan 05.
Article in English | MEDLINE | ID: mdl-17579356

ABSTRACT

The serotonin transporter gene has a 44 bp insertion/deletion polymorphism within the promoter region (5-HTTLPR) with two allelic forms, the long (L) and the short (S) variants. Association between the low-activity S variant and bipolar disorder (BPD) has been shown but its replication has not been consistent. It has also been described as an association between the S allele and suicidal behavior. Since suicidal behavior is a rather frequent event in BPD, an important question is whether suicidality, instead of bipolarity itself, could be related to S allele. We assessed 351 subjects (167 bipolar inpatients and 184 healthy controls). Diagnosis was conducted by a psychiatrist using a structured interview (MINI-PLUS), according to DSM-IV criteria. Suicidal behavior was assessed using a semi-structured instrument and a review of medical records. Genotyping of the 5-HTTLPR was performed using PCR. There were 77 patients with a history of previous suicide attempts. Bipolar patients and healthy controls showed comparable genotypic and allelic frequencies. Patients carrying the S allele made violent suicide attempts more frequently (chi(2) = 20.2; P = 0.0001) and made more suicide attempts (t = 2.6; P = 0.01). We were able to show an association between the S allele and suicidal behavior but not with BPD. Our data suggest that a phenotypic stratification, taking into account the suicidal behavior history, is of pivotal importance when performing association studies between BPD and 5-HTTLPR genotypes, which could explain previous contradictory results.


Subject(s)
Bipolar Disorder/genetics , Genetic Predisposition to Disease , Polymorphism, Genetic , Serotonin Plasma Membrane Transport Proteins/genetics , Suicide, Attempted , Adult , Alleles , Bipolar Disorder/diagnosis , Female , Genetic Linkage , Genotype , Humans , Male , Promoter Regions, Genetic
5.
Int J Dev Neurosci ; 25(2): 87-94, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17287103

ABSTRACT

Thyroid hormone (T3) deficiency impairs the development of the CNS, particularly myelination. We have previously described an increase in the frequency of morphological abnormalities in the central myelin sheath in a hypothyroidism model, which reinforced the hypothesis of a role for T3 in myelin compaction. However, there are no data concerning the cellular distribution of myelin proteins in hypothyroid animals. In the present work, we describe the distribution of 2',3'-cyclic nucleotide 3'-phosphodiesterase (CNPase), myelin basic protein (MBP) and proteolipid protein (PLP) throughout the central myelin sheath of a hypothyroidism model. We used euthyroid and hypothyroid adult rats at 90 days of age. In order to induce hypothyroid status, animals received 0.02% methimazol from the 19th gestation day onwards. After perfusion with a fixative mixture, small pieces of corpus callosum were obtained, dehydrated and embedded in LR White resin. Ultrathin sections were immunoreacted, using specific antibodies revealed by a secondary antibody coupled to colloidal gold particles of 10nm. Gold particle density per region of myelin sheath for each one of these proteins was obtained. In normal animals, CNPase, PLP and MBP were identified in sites that had already been described in previous studies. In hypothyroid animals, CNPase was identified in the region corresponding to compact lamellae, which normally does not contain this protein, while, in this same region, PLP and MBP immunolabeling were decreased. These results suggest that thyroid hormone deficiency impairs the distribution of the major oligodendrocyte/myelin markers. This effect may justify the reduction in myelin sheath compaction previously demonstrated in a similar model of hypothyroidism.


Subject(s)
Corpus Callosum/metabolism , Demyelinating Diseases/metabolism , Myelin Proteins/metabolism , Myelin Sheath/metabolism , Oligodendroglia/metabolism , 2',3'-Cyclic-Nucleotide Phosphodiesterases/metabolism , Animals , Antithyroid Agents , Biomarkers/metabolism , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Corpus Callosum/pathology , Demyelinating Diseases/etiology , Demyelinating Diseases/physiopathology , Hypothyroidism/chemically induced , Hypothyroidism/complications , Hypothyroidism/physiopathology , Methimazole , Microscopy, Immunoelectron , Myelin Basic Protein/metabolism , Myelin Proteins/ultrastructure , Myelin Proteolipid Protein/metabolism , Myelin Sheath/ultrastructure , Oligodendroglia/ultrastructure , Rats , Rats, Wistar
6.
Inflammation ; 30(6): 198-204, 2007 Dec.
Article in English | MEDLINE | ID: mdl-17665293

ABSTRACT

UNLABELLED: The present study investigated the acute inflammatory response (increase in vascular permeability and leukocytes migration) in the pleura of spontaneously hypertensive rats (SHR) and normotensive rats (NTR), using two different stimulus: carrageenan and active anaphylaxis. In addition, the role of endogenous nitric oxide in these responses was investigated. RESULTS: The inflammatory response induced by intrapleural carrageenan injection in SHR developed similarly to that in NTR. Treatment with L-NAME, reduced the intensity of this response in both groups of rats. The inflammatory response induced by active anaphylaxis in SHR and NTR was different. The increase in vascular permeability occurred later in the SHR compared to NTR. The number of leukocyte present in inflammatory exudates was increased at 4 h in both groups of rats. L-NAME treatment did not inhibit exudation at the intervals under analysis, however, reduced the number of mononuclear cells in the inflammatory exudate of SHR. CONCLUSION: The development of the inflammatory response in SHR differs from that in NTR, depending on the nature of the inflammatory stimulus. Endogenous NO plays a clear role in carrageenan-induced inflamma-tion, but not in immunologically mediated inflammation in the analyzed period.


Subject(s)
Anaphylaxis/complications , Chemotaxis, Leukocyte , Hypertension/metabolism , Leukocytes/immunology , Nitric Oxide/metabolism , Pleurisy/metabolism , Anaphylaxis/chemically induced , Anaphylaxis/immunology , Anaphylaxis/metabolism , Animals , Capillary Permeability , Carrageenan , Cell Migration Assays, Leukocyte , Chemotaxis, Leukocyte/drug effects , Disease Models, Animal , Enzyme Inhibitors/pharmacology , Exudates and Transudates/cytology , Exudates and Transudates/metabolism , Hypertension/immunology , Leukocytes/drug effects , Male , NG-Nitroarginine Methyl Ester/pharmacology , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/metabolism , Ovalbumin , Pleurisy/chemically induced , Pleurisy/etiology , Pleurisy/immunology , Rats , Rats, Inbred SHR , Rats, Wistar
7.
J Ethnopharmacol ; 105(1-2): 148-53, 2006 Apr 21.
Article in English | MEDLINE | ID: mdl-16307856

ABSTRACT

Ipomoea cairica L. Sweet (Convolvulaceae) is used in Brazilian folk medicine for the treatment of rheumatism and inflammations. Ipomoea cairica ethanolic extract (100, 300, 1000 and 3000 mg/kg; per os) induced dose-dependent reduction of response in the formalin test inflammatory phase in mice. The same dose range did not modify neurogenic pain in formalin test, tail-flick reflex latency, carrageenan-induced paw edema, and Rota-Rod test motor performance. From the bio-active fraction 3,5-di-O-caffeoylquinic acid and 4,5-di-O-caffeoylquinic acid were obtained. These compounds have been previously reported to have analgesic and antioxidative effects. A possible explanation for the antinociception is that somehow the compounds present in the extract reduced the release of pro-nociceptive mediators unrelated to carrageenan-induced edema, such as histamine. Interestingly, caffeoylquinic acid derivatives have been reported to inhibit histamine release on in vitro models. The isolated caffeoylquinic acids could explain, at least in part, the antinociceptive effect of Ipomoea cairica polar extract.


Subject(s)
Analgesics/pharmacology , Ipomoea/chemistry , Plant Extracts/pharmacology , Animals , Chromatography, High Pressure Liquid , Dose-Response Relationship, Drug , Magnetic Resonance Spectroscopy , Male , Mice , Spectrophotometry, Ultraviolet
8.
J Control Release ; 103(2): 419-34, 2005 Mar 21.
Article in English | MEDLINE | ID: mdl-15763624

ABSTRACT

The aim of this study was firstly to refine a rat model of arthritis, the adjuvant arthritis (AA) model, by studying the time course of the disease, introducing new evaluation methods such as haematological and biochemical parameters in order to identify the main stages of the disease. An optimisation of treatment schedule and evaluation criteria was developed. This refinement provided novel non-invasive anti-inflammatory treatment of the AA with SOD by using mixed lipid vesicles specially developed for transdermal delivery, Transfersomes (Tfs), this being the second major aim. The time course of AA includes a first stage: 1 day after the disease induction, the induced paw volume more than doubled and the paw circumference increased by approx. 50%. Two weeks later, another stage occurred where the disease shifted from the local arthritis form towards polyarthritis: an additional increase of volume and circumference of the induced and non-induced paws, occurred. The animals also started to loose weight around day 14 after the disease induction. Radiographic observable lesions increased correspondingly. Treatment of animals, started at day 1 after induction, by epicutaneous application of SOD-Tfs showed that 1 mg SOD/kg body weight is more efficient than 0.66 mg SOD /kg body weight. As a positive control, SOD liposomes intravenously injected were used for comparison and confirmed the biological efficiency of epicutaneously applied SOD in Tfs. SOD solution and empty Tfs epicutaneously applied exerted no effect. In addition, epicutaneous application of SOD-Tfs used prophylactically was able to suppress the induced rat paw oedema. Radiographic images showed less joint lesions in SOD-Tfs treated animals in comparison with control and placebo treated rats. It was shown for the first time that SOD incorporated into Tfs and applied onto a skin area not necessarily close to the inflamed tissue is able to promote non-invasive treatment of induced arthritis.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Arthritis, Experimental/drug therapy , Drug Carriers/administration & dosage , Superoxide Dismutase/therapeutic use , Animals , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Arthritis, Experimental/blood , Arthritis, Experimental/diagnostic imaging , Ascorbic Acid/blood , Drug Carriers/chemistry , Extremities/diagnostic imaging , Leukocyte Count , Liposomes , Male , Particle Size , Radiography , Rats , Rats, Wistar , Sulfhydryl Compounds/blood , Superoxide Dismutase/administration & dosage , Superoxide Dismutase/chemistry , Treatment Outcome
9.
Int J Dev Neurosci ; 18(8): 887-92, 2000 Dec.
Article in English | MEDLINE | ID: mdl-11154857

ABSTRACT

The effects of hypothyroidism on oligodendroglial differentiation and myelination are for the first time studied by immunohistochemical localization of an early oligodendroglial marker, the 2'3'cyclic nucleotide 3'phosphodiesterase (E.C. 3.1.4.37-CNPase), in developing rats. Two groups received methimazol; one during gestation (H) and another postnatally (PN). One H sub-group received thyroxine after birth (T). We observed a delay in CNPase expression followed by a decrease in the number of CNPase immunoreactive fibers in both H and PN groups. The T sub-group was not different from controls. Furthermore, the immunoreactive fibers, in mature hypothyroid animals, showed a continuous pattern of staining in contrast with a discontinuous one in controls. Myelinogenesis is a highly regulated timed event. CNPase links myelin related proteins to the cytoskeleton also interacting with membrane lipids during extension and wrapping of the oligodendroglial process around the axon (ensheathment phase). In mature myelinated fiber the CNPase is absent from compact myelin sheath, being located only in the inner and outer loops and in paranodal loops. Thus, our data suggest a disorder in myelin compaction and point once more to the post-natal period as critical for the mechanisms that are thyroid hormone regulated in myelinogenesis.


Subject(s)
2',3'-Cyclic-Nucleotide Phosphodiesterases/analysis , Brain/abnormalities , Brain/enzymology , Congenital Hypothyroidism , Hypothyroidism/metabolism , Myelin Sheath/enzymology , Animals , Antithyroid Agents , Brain/pathology , Female , Hypothyroidism/chemically induced , Hypothyroidism/pathology , Immunohistochemistry , Methimazole , Myelin Sheath/pathology , Oligodendroglia/enzymology , Oligodendroglia/pathology , Pregnancy , Prenatal Exposure Delayed Effects , Rats , Rats, Wistar , Thyroxine/pharmacology
10.
J Agric Food Chem ; 50(13): 3647-53, 2002 Jun 19.
Article in English | MEDLINE | ID: mdl-12059138

ABSTRACT

Diacetyl can be determined by adsorptive stripping voltammetry after derivatization with o-phenylenediamine. The method may be applicable to the determination of diacetyl in different foods, being a good alternative to other analytical methods. In this work an on-line automated analytical system for diacetyl determination in beer is described. A hanging mercury drop electrode voltammetric flow detector was used, and the analyte was determined without the traditional deoxygenation procedure. The method was successfully applied to the determination of diacetyl during beer fermentation and in the final product. The automation strategy used was based on a flow network similar to those used in multicommutated flow systems, with a pervaporation unit used for diacetyl separation. The developed system was tested in real conditions in the monitoring of brewing processes. The results obtained were similar to those obtained with the usual GC-ECD methodology in the 5-600 ppb range. The analytical rate of the developed method is about 12 determinations/h.


Subject(s)
Autoanalysis/methods , Beer/analysis , Diacetyl/analysis , Autoanalysis/instrumentation , Chromatography, Gas , Electrodes , Fermentation , Mercury
11.
J Ethnopharmacol ; 70(2): 151-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10771205

ABSTRACT

This work studied the antinociceptive, antiinflammatory and bronchodilator activities of hydroalcoholic extracts (HAEs) from Torresea cearensis, Justicia pectoralis, Eclipta alba, Pterodon polygaliflorus and Hybanthus ipecacuanha. These plants are largely used in north-eastern Brazil for respiratory tract diseases, and have in common coumarin, one of their active principles. The antinociceptive effects of all HAEs in mice were similar, and the inhibition of the acetic acid-induced writhing was 35-55% with 200 mg/kg, p.o. At this dose, the effect ranged from 41-77% with the formalin test in mice, and all the HAEs inhibited preferentially the 2nd phase of the response. In one case (P. polygaliflorus), the effect was partially reversed by naloxone. Except for the HAE from T. cearensis (200 mg/kg, p.o.) which inhibited carrageenan-induced edema by 47%, the others presented no effect orally but showed a significant activity intraperitoneally. On the other hand, T. cearensis was not active in the dextran model, while inhibitions with the other ones were lower than 30%. The bronchodilator activities of J. pectoralis and P. polygaliflorus HAEs as determined in isolated guinea-pig trachea were the most active.


Subject(s)
Analgesics, Non-Narcotic/pharmacology , Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Bronchodilator Agents/pharmacology , Coumarins/pharmacology , Plants, Medicinal , Animals , Brazil , Female , Guinea Pigs , In Vitro Techniques , Male , Mice , Rats , Rats, Wistar
12.
Rev Bras Enferm ; 49(3): 343-62, 1996.
Article in Portuguese | MEDLINE | ID: mdl-9295741

ABSTRACT

This study refers to a survey on Nursing labor force without specific qualification, in the city of Belo Horizonte, aiming at offering help to Nursing Organizations (ABEn, COREn, Syndicates), Minas Gerais State Health Secretary Office and MG District Health Secretary Office, for the elaboration and release of professional purposes programs for this Nursing team. The research has been accomplished in 82 hospitals, having 2,662 respondents as sample, which corresponds to 74.6% of the studied population.


Subject(s)
Hospitals, Urban , Nursing Staff, Hospital/supply & distribution , Personnel Staffing and Scheduling/statistics & numerical data , Adult , Brazil , Female , Humans , Male , Nursing Staff, Hospital/education , Surveys and Questionnaires , Workforce
13.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 425-429, mar.-abr. 2019. ilus
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1011278

ABSTRACT

O stent endovascular autoexpansível pode ser utilizado como forma de tratamento para estenose uretral em cães. O stent de nitinol é composto por uma liga de níquel e titânio que permite mudanças em suas estruturas sob a influência da temperatura corporal e tem excelente biocompatibilidade na uretra canina. Este estudo relata o caso de um cão, sem raça definida, 14 anos de idade, com histórico de disúria há duas semanas, diagnosticado com grande quantidade de cálculos e microcálculos na bexiga, no colo vesical e na uretra prostática, também cistite e hiperplasia prostática. Depois de tratamento para cistite, orquiectomia e cistotomia para retirada dos cálculos, porém sem melhora clínica após 30 dias de acompanhamento, com o paciente apresentando disúria, foi realizada uretrocistografia retrógrada, que evidenciou estenose da uretra prostática. Esse paciente foi encaminhado para procedimento de implantação de um stent de nitinol na uretra prostática. Imediatamente após o procedimento e até o presente momento, o paciente apresenta micção espontânea, sem qualquer sinal de disúria, sendo este o primeiro relato no Brasil do uso dessa técnica.(AU)


The endovascular stent is used for treatment of urethral stricture in dogs. The nitinol stent is composed by nickel and titanium alloy that allows changes in its structures under the influence of body temperature and has excellent biocompatibility in the canine urethra. This study aims to report a case of a 14 - year - old male dog without defined breed with dysuria for two weeks. Ultrasonographic evaluation revealed microcalculi and calculi in bladder, prostatic urethral obstruction and prostatic hyperplasia. Cystotomy was performed to remove uroliths, but after 30 days of hospitalization there was no clinical improvement. A double-contrast retrograde urethrocystography was performed and showed persistence of prostatic urethral obstruction. The pacient was submitted to a new surgery to place a self-expanding nitinol stent and presented spontaneous urination after the procedure. This is the first report of this technique in Brazil.(AU)


Subject(s)
Animals , Male , Dogs , Urethral Stricture/veterinary , Dysuria/veterinary , Self Expandable Metallic Stents/veterinary
14.
Science ; 344(6191): 1500-3, 2014 Jun 27.
Article in English | MEDLINE | ID: mdl-24970083

ABSTRACT

Methane is an important greenhouse gas and energy resource generated dominantly by methanogens at low temperatures and through the breakdown of organic molecules at high temperatures. However, methane-formation temperatures in nature are often poorly constrained. We measured formation temperatures of thermogenic and biogenic methane using a "clumped isotope" technique. Thermogenic gases yield formation temperatures between 157° and 221°C, within the nominal gas window, and biogenic gases yield formation temperatures consistent with their comparatively lower-temperature formational environments (<50°C). In systems where gases have migrated and other proxies for gas-generation temperature yield ambiguous results, methane clumped-isotope temperatures distinguish among and allow for independent tests of possible gas-formation models.


Subject(s)
Euryarchaeota/metabolism , Methane/biosynthesis , Methane/chemistry , Oil and Gas Fields , Biodegradation, Environmental , Carbon Isotopes , Gases , Hot Temperature , Models, Theoretical , Oil and Gas Fields/microbiology , Petroleum/metabolism , Temperature
15.
Anal Chim Acta ; 674(2): 166-75, 2010 Aug 03.
Article in English | MEDLINE | ID: mdl-20678626

ABSTRACT

The organic acids present in beer provide important information on the product's quality and history, determining organoleptic properties and being useful indicators of fermentation performance. NMR spectroscopy may be used for rapid quantification of organic acids in beer and different NMR-based methodologies are hereby compared for the six main acids found in beer (acetic, citric, lactic, malic, pyruvic and succinic). The use of partial least squares (PLS) regression enables faster quantification, compared to traditional integration methods, and the performance of PLS models built using different reference methods (capillary electrophoresis (CE), both with direct and indirect UV detection, and enzymatic essays) was investigated. The best multivariate models were obtained using CE/indirect detection and enzymatic essays as reference and their response was compared with NMR integration, either using an internal reference or an electrical reference signal (Electronic REference To access In vivo Concentrations, ERETIC). NMR integration results generally agree with those obtained by PLS, with some overestimation for malic and pyruvic acids, probably due to peak overlap and subsequent integral errors, and an apparent relative underestimation for citric acid. Overall, these results make the PLS-NMR method an interesting choice for organic acid quantification in beer.

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