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STUDY QUESTION: What is the vaginal polymorphonuclear (PMN) spermicidal mechanism to reduce the excess of sperm? SUMMARY ANSWER: We show that PMNs are very efficient at killing sperm by a trogocytosis-dependent spermicidal activity independent of neutrophil extracellular traps (NETs). WHAT IS KNOWN ALREADY: Trogocytosis has been described as an active membrane exchange between immune cells with a regulatory purpose. Recently, trogocytosis has been reported as a mechanism which PMNs use to kill tumour cells or Trichomonas vaginalis. STUDY DESIGN, SIZE, DURATION: We used in vivo murine models and human ex vivo sperm and PMNs to investigate the early PMN-sperm response. PARTICIPANTS/MATERIALS, SETTING, METHODS: We set up a live/dead sperm detection system in the presence of PMNs to investigate in vivo and ex vivo PMN-spermicidal activity by confocal microscopy, flow cytometry and computer-assisted sperm analysis (SCA). MAIN RESULTS AND THE ROLE OF CHANCE: We revealed that PMNs are highly efficient at killing sperm by way of a NETs-independent, contact-dependent and serine proteases-dependent engulfment mechanism. PMNs 'bite' sperm and quickly reduce sperm motility (within 5 min) and viability (within 20 min) after contact. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: This study was conducted using murine models and healthy human blood PMNs; whether it is relevant to human vaginal PMNs or to cases of infertility is unknown. WIDER IMPLICATIONS OF THE FINDINGS: Vaginal PMNs attack and immobilize excess sperm in the vagina by trogocytosis because sperm are exogenous and may carry pathogens. Furthermore, this mechanism of sperm regulation has low mucosal impact and avoids an exacerbated inflammatory response that could lead to mucosal damage or infertility. STUDY FUNDING/COMPETING INTEREST(S): This work was partially supported by Ministry of Economy and Competitiveness ISCIII-FIS grants, PI16/00050, and PI19/00078, co-financed by ERDF (FEDER) Funds from the European Commission, 'A way of making Europe' and IiSGM intramural grant II-PI-MRC-2017. M.R. holds a Miguel Servet II contract (CPII14/00009). M.C.L. holds IiSGM intramural contract. There are no competing interests.
Assuntos
Neutrófilos , Motilidade dos Espermatozoides , Animais , Europa (Continente) , Feminino , Humanos , Masculino , Camundongos , Espermatozoides , VaginaRESUMO
SATB2-associated syndrome (SAS) is a multisystemic disorder caused by alterations of the SATB2 gene. We describe the phenotype and genotype of 12 individuals with 10 unique (de novo in 11 of 11 tested) pathogenic variants (1 splice site, 5 frameshift, 3 nonsense, and 2 missense) in SATB2 and review all cases reported in the published literature caused by point alterations thus far. In the cohort here described, developmental delay (DD) with severe speech compromise, facial dysmorphism, and dental anomalies were present in all cases. We also present the third case of tibial bowing in an individual who, just as in the previous 2 individuals in the literature, also had a truncating pathogenic variant of SATB2. We explore early genotype-phenotype correlations and reaffirm the main clinical features of this recognizable syndrome: universal DD with severe speech impediment, mild facial dysmorphism, and high frequency of craniofacial anomalies, behavioral issues, and brain neuroradiographic changes. As the recently proposed surveillance guidelines for individuals with SAS are adopted by providers, further delineation of the frequency and impact of other phenotypic traits will become available. Similarly, as new cases of SAS are identified, further exploration of genotype-phenotype correlations will be possible.
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Anormalidades Craniofaciais/genética , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Proteínas de Ligação à Região de Interação com a Matriz/genética , Fatores de Transcrição/genética , Adolescente , Criança , Pré-Escolar , Anormalidades Craniofaciais/fisiopatologia , Deficiências do Desenvolvimento/fisiopatologia , Exoma/genética , Feminino , Mutação da Fase de Leitura , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Deficiência Intelectual/fisiopatologia , Masculino , FenótipoRESUMO
Intellectual disability (ID) affects about 3% of the population and has a male gender bias. Of at least 700 genes currently linked to ID, more than 100 have been identified on the X chromosome, including KIAA2022. KIAA2022 is located on Xq13.3 and is expressed in the developing brain. The protein product of KIAA2022, Xlinked Intellectual Disability Protein Related to Neurite Extension (XPN), is developmentally regulated and is involved in neuronal migration and cell adhesion. The clinical manifestations of lossoffunction KIAA2022 mutations have been described previously in 15 males, born from unaffected carrier mothers, but few females. Using wholeexome sequencing, we identified a cohort of five unrelated female patients with de novo probably gene damaging variants in KIAA2022 and core phenotypic features of ID, developmental delay, epilepsy refractory to treatment, and impaired language, of similar severity as reported for male counterparts. This study supports KIAA2022 as a novel cause of Xlinked dominant ID, and broadens the phenotype for KIAA2022 mutations.
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Epilepsia , Deficiência Intelectual , Mutação com Perda de Função , Proteínas do Tecido Nervoso , Epilepsia/genética , Exoma , Feminino , Genes Ligados ao Cromossomo X , Humanos , Deficiência Intelectual/genética , Mutação , Proteínas do Tecido Nervoso/genética , Malformações do Sistema Nervoso/genética , FenótipoRESUMO
PURPOSE: To investigate neonatal malformation, prematurity, and stillbirth in singleton and multiple pregnancies derived from different Assisted Reproductive Techniques (ART). METHODS: In this prospective cohort study data were collected, from private and public Spanish IVF units, during the years 2008 and 2009. During this period, 8,682 pregnancies were analysed from the initial 14,119 pregnancies reported. Pregnancies included in the study derived from IUI (n = 1,065), IVF (n = 838), ICSI (n = 5,080), FET (n = 1,404) and PGD (n = 295). This first analysis focuses primarily on neonatal malformation, prematurity, and stillbirth both in singleton and multiple pregnancies derived from different ART. Malformations were classified according to the WHO ICD 10 code. RESULTS: Malformations were found in 0.83 % of our newborns. No differences in malformations were observed between singletons or multiples independently of the ART used. There was a significant difference in prematurity rate among singletons depending on treatment but this association was not observed in multiple pregnancies. Stillbirth was significantly lower in singleton (0.72 %) than in multiple pregnancies (1.82 %). CONCLUSIONS: The percentage of malformations observed in ART newborns was similar to the rate observed in the normally-conceived Spanish population. Multiplicity seems to be the most important factor associated with an increased incidence of newborn complications such as prematurity or stillbirth.
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Anormalidades Congênitas/epidemiologia , Recém-Nascido Prematuro , Técnicas de Reprodução Assistida/estatística & dados numéricos , Natimorto/epidemiologia , Estudos de Coortes , Feminino , Humanos , Mortalidade Infantil , Recém-Nascido , Idade Materna , Gravidez , Técnicas de Reprodução Assistida/efeitos adversos , Espanha , Inquéritos e QuestionáriosRESUMO
The appearance of multiple satellite lesions is a rare complication of the treatment of a primary pyogenic granuloma lesion. We report 5 cases of recurrent pyogenic granuloma in patients aged between 4 and 31 years. The lesions resolved spontaneously after 1 to 9 months. Although the diagnosis and treatment of recurrent pyogenic granuloma can be problematic, this condition is benign and frequently self-limiting.
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Granuloma Piogênico , Adolescente , Adulto , Criança , Pré-Escolar , Diagnóstico Diferencial , Eletrocoagulação , Feminino , Granuloma Piogênico/diagnóstico , Granuloma Piogênico/patologia , Granuloma Piogênico/cirurgia , Humanos , Masculino , Recidiva , Remissão Espontânea , Estudos Retrospectivos , Neoplasias Cutâneas/diagnósticoRESUMO
As the worldwide population continues to rise, so does global demand for agricultural production. This scenario of uncertain food supply is exacerbated by the high salinization of soils worldwide, a serious constraint to crop productivity. In this context, there is an increasing need for alternative sustainable crops. Halophytes are thought to be a promising alternative food source due to their natural ability to grow in saline soils and their multiple potential uses in the food industry. In this study, the protein and fatty acid content of the halophyte Halimione (Atriplex) portulacoides (L.) was studied in different saline conditions. Although more studies are needed to explore the nutritional properties of H. portulacoides, the data presented here suggest that this halophyte should be considered as a promising food crop for saline agriculture.
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Chenopodiaceae/química , Ácidos Graxos/análise , Proteínas de Plantas/análise , Salinidade , Plantas Tolerantes a Sal/química , Solo/químicaRESUMO
Demographic aging is one of the most serious challenges facing our society. Although we live longer, we do not live better because it is considered that approximately 16-20% of our life is spent in late-life morbidity. Older people have the greatest risk of developing frailty increasing the risk of presenting various adverse health events such as low quality of life, disability, hospitalization and even death. Frail men and women over 65 years old have lower muscle quality and muscle mass and higher percentage of body fat than non-frail people of the same age. In this review we will address the main physiological changes in the muscular and nervous system associated to aging. More specifically we will review the changes in muscle mass, quality, and strength relating them with the decrease in capillarization and muscular oxidative capacity as well as with the alterations in protein synthesis in the muscle with aging. The last section of the manuscript will be devoted to the animal models of frailty and the indexes developed to measure frailty in these models. We will finally address the importance of exercise training as an intervention to delay or even reverse frailty.
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INTRODUCTION: There are currently 3holmium laser, YAG (Ho:YAG) endolithotripsy procedures that are considered basic (fragmentation, pulverisation, "pop-corn" technique). We present the technique of fragmentation targeted at preferred discontinuities (FTPD), a new concept of endolithotripsy by Ho:YAG laser. MATERIAL AND METHODS: The FTPD technique is based on the selective application of energy (targeting a specific preselected point) to an area that is visually prone to the formation of a fracture line or preferred discontinuity (conditioned by the anisotropy of the urolithiasis). The ideal energy regimen (setting) is a high range of working energy (2-3J) with a very low frequency range (5-8Hz) and short pulse width. Between January 2015 to February 2017, the FTPD technique was used in 37 procedures (7 NLP, 16 RIRS, 12 URS, 2 cystolithotomies), with a Ho:YAG laser (Lumenis Pulse 120H®, Tel-Aviv, Israel). Maximum power used: 24W (3J/8Hz) with fibres of 365µ and 273µ (URS, RIRS), and 32W (4J/8Hz) with fibres of 550µ (NLP, cystolithotomy). RESULTS: Strategic improvement was achieved in all cases using the TFPD technique to continue the endolithotripsy or remove fragments. No complications were recorded after the use of this method. CONCLUSIONS: FTPD can be considered a complementary option in combination with the basic methods of fragmentation and pulverisation. In our experience, it constitutes significant progress in optimising the performance of Ho:YAG laser endolithotripsy.
Assuntos
Lasers de Estado Sólido/uso terapêutico , Litotripsia a Laser/métodos , Urolitíase/terapia , Endoscopia , HumanosRESUMO
OBJECTIVE: To report 10 instances of decompression retinopathy (DCR) developing after intraocular surgery. METHODS: This was a case series of 9 patients (10 eyes). Decompression retinopathy occurred after trabeculectomy (4 eyes), phacomulsification (3 eyes), Ahmed valve placement (1 eye), silicone oil removal (1 eye) and vitrectomy (1 eye). Fundus evaluation and fluorescein angiography were performed in all instances. RESULTS: Superficial, subhyaloidal, and deep retinal hemorrhages were noted in the posterior pole and peripheral retina; some of these had a white center. Nine (90%) of 10 eyes had a previous diagnosis of glaucoma, 6 having primary open-angle glaucoma, 2 neovascular glaucoma and 1 secondary glaucoma associated with intravitreal silicone oil. The patient without glaucoma had a history of cataract surgery and a vitrectomy to close a macular hole. The mean preoperative intraocular pressure (IOP) was 36.6 mm Hg (range: 15 to 58 mm Hg) despite maximal medical therapy in those patients with glaucoma. Fluorescein angiography demonstrated hypofluorescence throughout the study associated with superficial, and deep retinal hemorrhages. On the first post-operative day, visual acuity (VA) decreased more than 2 ETDRS lines in all cases. A pars plana vitrectomy (PPV) was performed in 5 eyes. All patients improved more than 2 ETDRS lines at a mean of 9 months after DCR. CONCLUSIONS: A gradual decrease of IOP pre-operatively and intra-operatively is recommended in order to avoid this complication. Early vitrectomy represents a useful treatment in many cases. A previous history of glaucoma seems to be an important risk factor for the development of DCR.
Assuntos
Pressão Intraocular , Procedimentos Cirúrgicos Oftalmológicos/efeitos adversos , Doenças Retinianas/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , MasculinoRESUMO
The effect of ascorbic acid depletion on the 1-methyl-4-phenylpyridinium ion (MPP+)-induced neurotoxicity in the dopaminergic system has been tested in guinea-pig striatal slices. Guinea-pigs were divided into three groups and fed on a control diet, ascorbic acid-free diet and ascorbic acid-supplemented diet, respectively. Diets were maintained during 30 days. Striatal slices from ascorbic acid-deficient animals showed the highest levels of dopamine following 25 microM MPP+ treatment; the results from animals under this treatment condition were statistically different from both control and ascorbic acid-supplemented animals under identical experimental conditions. In addition, neurochemical analysis demonstrated that the levels of ascorbic acid and dehydroascorbic acid were highly reduced in striatal tissue from ascorbic acid-deficient animals, thus proving scorbutic conditions in our experimental animals. In view of the higher resistance of the ascorbic acid-deficient animals to the neurotoxicity elicited by MPP+, additional dopaminergic parameters were also measured in striatal tissue from ascorbic acid-deficient animals in the absence of MPP+, including levels of dopamine and its metabolites, tyrosine hydroxylase activity and dopamine uptake, with the aim of finding an explanation for this unexpected result. While dopamine levels and tyrosine hydroxylase activity remained close to control levels, dopamine uptake was significantly reduced in striatal synaptosomes from ascorbic acid-deficient animals as compared with control animals. Since MPP+ is actively accumulated into dopaminergic nerve terminals via the high-affinity dopamine uptake system, this finding could explain the higher resistance of ascorbic acid-deficient animals to the dopamine-depleting effect induced by MPP+ toxicity assayed in striatal slices.
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1-Metil-4-fenilpiridínio/toxicidade , Deficiência de Ácido Ascórbico/metabolismo , Doenças do Sistema Nervoso Central/induzido quimicamente , Dopaminérgicos/toxicidade , Neostriado/enzimologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Aminoácidos/metabolismo , Animais , Peso Corporal , Doenças do Sistema Nervoso Central/metabolismo , Ácido Desidroascórbico/metabolismo , Dopamina/metabolismo , Feminino , Cobaias , Ácido Homovanílico/metabolismo , Técnicas de Cultura de Órgãos , Tirosina 3-Mono-Oxigenase/metabolismo , Ácido Úrico/metabolismoRESUMO
Prenatal exclusion of Huntington disease (HD) may be carried out by analysis of cosegregating DNA markers on a first-trimester chorionic villus sample. The conventional Southern blot method is time-consuming and requires microgram quantities of DNA and milligram quantities of villus tissue. The use of the polymerase chain reaction (PCR) to amplify genomic DNA by a factor of 10(7) or more makes it possible to do analyses on very small samples in a few hours and without recourse to Southern blotting or hybridization with radioactive probes. We report on a fetus at risk of HD; prenatal testing was carried out by using the PCR to amplify a polymorphic DNA sequence adjacent to the HD locus. The risk of the fetus inheriting the HD gene could not be excluded and the pregnancy was terminated. This represents an example of gene tracking by using amplification of a restriction fragment length polymorphism at some distance from the relevant mutation.
Assuntos
DNA Polimerase Dirigida por DNA , DNA/genética , Amplificação de Genes , Marcadores Genéticos , Doença de Huntington/genética , Diagnóstico Pré-Natal , Adulto , Amostra da Vilosidade Coriônica , Feminino , Humanos , Linhagem , Polimorfismo de Fragmento de Restrição , GravidezRESUMO
We have recently developed cell line models that express the endogenous rat preprotachykinin-A (rPPT) gene and support reporter gene expression directed by the rPPT promoter. These are the neuronal derived cell line NF2C and the pancreatic cell lines RINm5F and a derivative RIN-1027-B2. Reporter gene activity in these cell lines is similar to that observed in primary cultures of rat dorsal root ganglion neurons. Analysis of reporter gene expression supported by various fragments of the rPPT promoter demonstrated that although -865 to +92 supported expression, addition of fragments between +92 and +500 led to repression of expression. Two previously defined octamer binding motifs, present both 5' and 3' of the major transcriptional start site, have been postulated to be potential enhancers of rPPT activity and we have now used these cell lines to determine the role of these regions in the rPPT promoter. Site specific mutagenesis of these elements has shown not only that both sites are potential enhancers of gene expression but also that the 3' element binds multiple factors, of which at least one has repressor function. Binding of this repressor protein over or adjacent to the 3' octamer binding protein site leads to the observed repression of promoter activity in the -865 to +500 construct relative to the to -865 to +92 the fragment.
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Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Regiões Promotoras Genéticas/genética , Precursores de Proteínas/genética , Sequências Reguladoras de Ácido Nucleico , Taquicininas/genética , Fatores de Transcrição/metabolismo , Motivos de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Cloranfenicol O-Acetiltransferase/biossíntese , Cloranfenicol O-Acetiltransferase/genética , Elementos Facilitadores Genéticos/genética , Genes Reporter , Células HeLa , Fator C1 de Célula Hospedeira , Humanos , Luciferases/biossíntese , Luciferases/genética , Mutagênese Sítio-Dirigida , Neurônios/citologia , Fator 1 de Transcrição de Octâmero , Pâncreas/citologia , Reação em Cadeia da Polimerase , Ratos , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/genética , Proteínas Repressoras/química , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , TransfecçãoRESUMO
We compared cerebrospinal fluid (CSF) and serum levels, and the CSF/serum ratio of alpha-tocopherol (vitamin E), measured by HPLC, in 36 patients with multiple sclerosis (MS) and 32 matched controls. The mean CSF vitamin E levels and the CSF/serum vitamin E ratio did not differ significantly between the two study groups. The serum levels of vitamin E and the serum vitamin E/cholesterol ratio were significantly lower in MS patients when compared with controls (P < 0.05 and P < 0.01, respectively). These values were not correlated with age, age at onset and duration of the disease in the patients group. These results suggest that CSF vitamin E concentrations are not a marker of activity of MS activity.
Assuntos
Esclerose Múltipla/líquido cefalorraquidiano , Vitamina E/líquido cefalorraquidiano , Adulto , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Masculino , Esclerose Múltipla/sangue , Vitamina E/sangueRESUMO
Chickpea protein isolate was used as starting material for the production of hypoallergenic protein hydrolysates. Western blotting of the protein isolate showed that IgE in sensitized patient sera strongly bound to the basic polypeptidic chains and recognized the acidic ones of 11S globulin. During the hydrolysis process by the individual and/or sequential action of endo- and exoproteases, a high reduction of antigenic activity was observed. Results suggest that the presence of intact or partially hydrolyzed basic polypeptide chains of 11S globulin are responsible for the formation of IgE complexes in protein hydrolysates obtained by exoprotease treatment; however, the digestion of these polypeptide chains by individual action of endoprotease caused a high loss of antigenic activity. The most effective reduction of antigenicity, >90%, was observed in extensive hydrolyzed chickpea proteins obtained by sequential treatment with endo- and exopeptidases. This chickpea protein hydrolysate could be useful for the elaboration of specialized hypoallergenic food products.
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Fabaceae , Hipersensibilidade Alimentar/imunologia , Proteínas de Plantas/imunologia , Plantas Medicinais , Hidrolisados de Proteína/imunologia , Western Blotting , Endopeptidases , Hipersensibilidade Alimentar/sangue , Humanos , Imunoglobulina ERESUMO
Chickpea legumin has been purified and incubated under oxidizing conditions with linoleic acid to investigate the influence of this acid on the structure and nutritional quality of the protein. At the end of the incubation time, >30% of the linoleic acid was oxidized. The oxidized linoleic acid was highly detrimental to legumin, and the electrophoretic pattern of the protein was completely changed after the incubation period. Nevertheless, neither polymerization nor cleavage of the protein was observed as deduced from gel filtration chromatography, suggesting that the changes observed in native electrophoresis were probably due to oxidation of legumin. The incubation of legumin with linoleic acid also produced a diminution of the contents of methionine and histidine, by 81.3 and 24.3%, respectively. Finally, in vitro protein digestibility of chickpea legumin was also seriously affected by the incubation with linoleic acid, decreasing from 84.1 to 69.2%.
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Fabaceae , Ácido Linoleico/química , Proteínas de Plantas/química , Plantas Medicinais , Aminoácidos/análise , Cromatografia em Gel , Oxirredução , Proteínas de Plantas/isolamento & purificação , Sementes/química , LeguminasRESUMO
A chickpea 2S albumin has been purified by solubilization in 60% methanol and ion-exchange chromatography. Under denaturing conditions it is composed of two peptides of 10 and 12 kDa. Native molecular mass determined by gel filtration chromatography is 20 kDa. Amino acid composition shows that it is rich in sulfur amino acids, mainly cysteine with 4.6% of the total. On the other hand, it has antinutritional characteristics of being allergenic for chickpea-sensitive individuals and inhibitory against porcine chymotrypsin with a lesser degree toward trypsin. The results of interest from a nutritional point of view are discussed.
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Fabaceae/química , Proteínas de Plantas/química , Plantas Medicinais , Precursores de Proteínas/química , Albuminas 2S de Plantas , Aminoácidos/análise , Antígenos de Plantas , Quimotripsina/antagonistas & inibidores , Peso Molecular , Proteínas de Plantas/isolamento & purificação , Inibidores de Proteases/farmacologia , Precursores de Proteínas/isolamento & purificação , Inibidores da Tripsina/farmacologiaRESUMO
Two new indolocarbazole alkaloids, 4'-N-methyl-5'-hydroxystaurosporine (2) and 5'-hydroxystaurosporine (3), were isolated together with the known staurosporine (1) from the culture broth of a marine Micromonospora sp. (strain L-31-CLCO-002). The fermentation, structural data and cytotoxic activities of these compounds against various tumor cell lines are given.
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Antineoplásicos/isolamento & purificação , Carbazóis/isolamento & purificação , Indóis/isolamento & purificação , Micromonospora/química , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Carbazóis/química , Carbazóis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HT29 , Humanos , Indóis/química , Indóis/farmacologia , Concentração Inibidora 50 , Espectroscopia de Ressonância Magnética , Camundongos , Micromonospora/crescimento & desenvolvimento , Micromonospora/metabolismo , Estaurosporina/análogos & derivados , Células Tumorais Cultivadas , Microbiologia da ÁguaRESUMO
A study of the anaerobic digestion of wastewater derived from the production of protein isolates from extracted sunflower flour was carried out in a laboratory-scale, mesophilic (35 degrees C) fluidized-bed reactor with saponite as bacterial support. Chemical oxygen demand (COD) removal efficiencies in the range of 98.3-80.0% were achieved in the reactor at organic loading rates (OLR) of between 0.6 and 9.3 g COD/I d, hydraulic retention times (HRT) of between 20.0 and 1.1 d and average feed COD concentration of 10.6 g/l. Eighty percent of feed COD could be removed up to OLR of 9.3 g COD/l d. The yield coefficient of methane production was 0.33 l of methane (at STP) per gram of COD removed and was virtually independent of the OLR applied. Because the buffering capacity of the experimental system was maintained at favorable levels with excess total alkalinity present at all loadings, the rate of methanogenesis was not affected by loading. The experimental data indicated that a total alkalinity in the range of 2,000-2,460 mg/l as CaCO3 was sufficient to prevent the pH from dropping to below 7.0 for OLR of up to 9.3 g COD/l d. The volatile fatty acid (VFA) levels and the VFA/alkalinity ratio were lower than the suggested limits for digester failure (0.3-0.4) for OLR and HRT up to 9.3 g COD/l d and 1.1 d, respectively. For a HRT of 0.87 d (OLR of 12.1 g COD/l d) the start of acidification was observed in the reactor.
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Helianthus/metabolismo , Resíduos Industriais , Oxigênio/metabolismo , Eliminação de Resíduos Líquidos/instrumentação , Eliminação de Resíduos Líquidos/métodos , Ácidos Graxos/metabolismo , Farinha , Concentração de Íons de Hidrogênio , Fatores de TempoRESUMO
In order to design a minimal process for cantaloupe, the water activity of the fruit was reduced until 0.976 through vacuum osmotic dehydration and the optimum combination of microbial preservatives (100 ppm sodium sulfite, 600 ppm potassium sorbate, 0.5% L-ascorbic acid and 1% citric acid), that contributed to minimize (p < 0.05), the content of aerobic mesophilic bacteria, molds and yeast, was determined through a 2k multifactorial design. In the second experimental stage, the conditions previously mentioned were tested together with the application of fruit's blanching (98 degrees C/3 min) with saturated steam and product storage in three different modified atmospheres (6% O2-6% CO2, 5% O2-10% CO2 and atmospheric air). In such sense, the application of microbial preservatives together with fruit's blanching and atmospheric air in high barrier packages (30 mu nylon) contributed to extent the shelf life of the cantaloupe minimally processed during 14 days on the basis of aerobic mesophilic bacteria, psychrotrophic bacteria, acid lactic bacteria, enterobacteria, molds, yeast and the sensory attributes color, odour, taste and texture.