Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 199
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Graefes Arch Clin Exp Ophthalmol ; 262(6): 1883-1897, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38189974

RESUMO

PURPOSE: Retinitis pigmentosa (RP) comprises a genetically and clinically heterogeneous group of inherited retinal degenerations, where 20-30% of patients exhibit extra-ocular manifestations (syndromic RP). Understanding the genetic profile of RP has important implications for disease prognosis and genetic counseling. This study aimed to characterize the genetic profile of syndromic RP in Portugal. METHODS: Multicenter, retrospective cohort study. Six Portuguese healthcare providers identified patients with a clinical diagnosis of syndromic RP and available genetic testing results. All patients had been previously subjected to a detailed ophthalmologic examination and clinically oriented genetic testing. Genetic variants were classified according to the American College of Medical Genetics and Genomics; only likely pathogenic or pathogenic variants were considered relevant for disease etiology. RESULTS: One hundred and twenty-two patients (53.3% males) from 100 families were included. Usher syndrome was the most frequent diagnosis (62.0%), followed by Bardet-Biedl (19.0%) and Senior-Løken syndromes (7.0%). Deleterious variants were identified in 86/100 families for a diagnostic yield of 86.0% (87.1% for Usher and 94.7% for Bardet-Biedl). A total of 81 genetic variants were identified in 25 different genes, 22 of which are novel. USH2A and MYO7A were responsible for most type II and type I Usher syndrome cases, respectively. BBS1 variants were the cause of Bardet-Biedl syndrome in 52.6% of families. Best-corrected visual acuity (BCVA) records were available at baseline and last visit for 99 patients (198 eyes), with a median follow-up of 62.0 months. The mean BCVA was 56.5 ETDRS letters at baseline (Snellen equivalent ~ 20/80), declining to 44.9 ETDRS letters (Snellen equivalent ~ 20/125) at the last available follow-up (p < 0.001). CONCLUSION: This is the first multicenter study depicting the genetic profile of syndromic RP in Portugal, thus contributing toward a better understanding of this heterogeneous disease group. Usher and Bardet-Biedl syndromes were found to be the most common types of syndromic RP in this large Portuguese cohort. A high diagnostic yield was obtained, highlighting current genetic testing capabilities in providing a molecular diagnosis to most affected individuals. This has major implications in determining disease-related prognosis and providing targeted genetic counseling for syndromic RP patients in Portugal.


Assuntos
Testes Genéticos , Mutação , Retinose Pigmentar , Humanos , Retinose Pigmentar/genética , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/epidemiologia , Portugal/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Adolescente , Adulto Jovem , Criança , Idoso , Linhagem , Síndromes de Usher/genética , Síndromes de Usher/diagnóstico , Síndromes de Usher/epidemiologia , Pré-Escolar , Análise Mutacional de DNA , Seguimentos , DNA/genética , Proteínas do Olho/genética
2.
Molecules ; 29(10)2024 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-38792132

RESUMO

In this study, different extraction methods and conditions were used for the extraction of antioxidants from brown macroalgae Fucus spiralis. The extraction methodologies used were ultrasound-assisted extraction (ultrasonic bath and ultrasonic probe), extraction with a vortex, extraction with an Ultra-Turrax® homogenizer, and high-pressure-assisted extraction. The extracts were analyzed for their total phenolic content (TPC) and their antioxidant activity, and evaluated through the 2,2-difenil-1-picrilhidrazil (DPPH) free radical scavenging method and ferric reducing antioxidant power (FRAP) assay. Ultrasonic probe-assisted extraction yielded the highest values of TPC (94.78-474.16 mg gallic acid equivalents/g extract). Regarding the antioxidant activity, vortex-assisted extraction gave the best DPPH results (IC50 1.89-16 µg/mL), while the highest FRAP results were obtained using the Ultra-Turrax® homogenizer (502.16-1188.81 µmol ascorbic acid equivalents/g extract). For each extraction method, response surface methodology was used to analyze the influence of the experimental conditions "extraction time" (t), "biomass/solvent ratio" (R), "solvent" (S, water % in water/ethanol mixture), and "pressure" (P) on TPC, DPPH, and FRAP of the F. spiralis extracts. In general, higher TPC content and higher antioxidant capacity (lower IC50 and higher FRAP) were obtained with higher R, t, and P, and lower S (higher ethanol %). The model regarding the combined effects of independent variables t, R, and S on the FRAP response values for vortex-assisted extractions best fitted the experimental data (R2 0.957), with optimal extraction conditions of t = 300 s, R = 50 g, and S = 25%.


Assuntos
Antioxidantes , Fucus , Fucus/química , Antioxidantes/química , Antioxidantes/farmacologia , Antioxidantes/isolamento & purificação , Fenóis/química , Fenóis/isolamento & purificação , Fenóis/análise , Alga Marinha/química , Compostos de Bifenilo/química , Compostos de Bifenilo/antagonistas & inibidores , Picratos/química , Picratos/antagonistas & inibidores , Solventes/química
3.
Crit Rev Food Sci Nutr ; 63(26): 8357-8374, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35357258

RESUMO

Meat constitutes one the main protein sources worldwide. However, ethical and health concerns have limited its consumption over the last years. To overcome this negative impact, new ingredients from natural sources are being applied to meat products to obtain healthier proteinaceous meat products. Algae is a good source of unsaturated fatty acids, proteins, essential amino acids, and vitamins, which can nutritionally enrich several foods. On this basis, algae have been applied to meat products as a functional ingredient to obtain healthier meat-based products. This paper mainly reviews the bioactive compounds in algae and their application in meat products. The bioactive ingredients present in algae can give meat products functional properties such as antioxidant, neuroprotective, antigenotoxic, resulting in healthier foods. At the same time, algae addition to foods can also contribute to delay microbial spoilage extending shelf-life. Additionally, other algae-based applications such as for packaging materials for meat products are being explored. However, consumers' acceptance for new products (particularly in Western countries), namely those containing algae, not only depends on their knowledge, but also on their eating habits. Therefore, it is necessary to further explore the nutritional properties of algae-containing meat products to overcome the gap between new meat products and traditional products, so that healthier algae-containing meat can occupy a significant place in the market.


Assuntos
Produtos da Carne , Produtos da Carne/análise , Carne/análise , Antioxidantes , Vitaminas , Nível de Saúde
4.
Appl Microbiol Biotechnol ; 107(16): 5063-5077, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37382612

RESUMO

Nannochloropsis oculata is naturally rich in eicosapentaenoic acid (EPA). To turn this microalga into an economically viable source for commercial applications, extraction efficiency must be achieved. Pursuing this goal, emerging technologies such as high hydrostatic pressure (HHP) and moderate electric fields (MEF) were tested, aiming to increase EPA accessibility and subsequent extraction yields. The innovative approach used in this study combined these technologies and associated tailored, less hazardous different solvent mixtures (SM) with distinct polarity indexes. Although the classical Folch SM with chloroform: methanol (PI 4.4) provided the highest yield concerning total lipids (166.4 mglipid/gbiomass), diethyl ether: ethanol (PI 3.6) presented statistically higher values in terms of EPA per biomass, corresponding to 1.3-fold increase. When SM were used in HHP and MEF, neither technology independently improved EPA extraction yields, although the sequential combination of technologies did result in 62% increment in EPA extraction. Overall, the SM and extraction methodologies tested (HHP-200 MPa, 21 °C, 15 min, followed by MEF processing at 40 °C, 15 min) enabled increased EPA extraction yields from wet N. oculata biomass. These findings are of high relevance for the food and pharmaceutical industries, providing viable alternatives to the "classical" extraction methodologies and solvents, with increased yields and lower environmental impact. KEY POINTS: • Et2O: EtOH is a less toxic and more efficient alternative to Folch solvent mixture • HHP or MEF per se was not able to significantly increase EPA extraction yield • Combinations of HHP and MEF technologies increased both lipids and EPA yields.


Assuntos
Microalgas , Estramenópilas , Ácido Eicosapentaenoico , Solventes , Metanol , Etanol , Biomassa
5.
Graefes Arch Clin Exp Ophthalmol ; 261(3): 867-878, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36050475

RESUMO

PURPOSE: Phenotypic heterogeneity with variable severity has been reported in female carriers of retinitis pigmentosa GTPase regulator (RPGR) mutations, including a male-type phenotype. A phenomenon not fully understood is peripapillary retinal nerve fiber layer (pRNFL) thickening in male patients with RPGR-associated X-linked retinitis pigmentosa, especially in the temporal sector. We aim to describe the genetic spectrum, retinal phenotypes, and pRNFL thickness in a cohort of Caucasian RPGR-mutation heterozygotes. METHODS: A cross-sectional study was conducted at an inherited retinal degeneration (IRD) reference center in Portugal. Female patients heterozygous for clinically significant RPGR variants were identified using the IRD-PT registry. A complete ophthalmologic examination was performed, complemented by macular and peripapillary spectral domain optical coherence tomography (SD-OCT), ultra-widefield color fundus photography (UW-CFP), and ultra-widefield fundus autofluorescence (UW-FAF). The retinal phenotypes were graded according to previously described classifications. The pRNFL thickness across the superior, inferior, nasal, and temporal quadrants was compared to the Spectralis® RNFL age-adjusted reference database. RESULTS: Forty-eight eyes from 24 females (10 families) were included in the study. Genetic analysis yielded 8 distinct clinically significant frameshift variants in RPGR gene, 3 of which herein reported for the first time. No association was found between mutation location and best-corrected visual acuity (BCVA) or retinal phenotype. Age was associated with worse BCVA and more advanced phenotypes on SD-OCT, UW-CFP, and UW-FAF. Seven women (29.17%) presented a male-type phenotype on UW-FAF in at least one eye. An association was found between UW-FAF and pRNFL thickness in the temporal sector (p = 0.003), with the most advanced fundus autofluorescence phenotypes showing increased pRNFL thickness in this sector. CONCLUSION: This study expands the genetic landscape of RPGR-associated disease by reporting 3 novel clinically significant variants. We have shown that clinically severe phenotypes are not uncommon among female carriers. Furthermore, we provide novel insights into pRNFL changes observed in RPGR heterozygotes that mimic what has been reported in male patients.


Assuntos
Degeneração Retiniana , Retinose Pigmentar , Feminino , Humanos , Masculino , Estudos Transversais , Proteínas do Olho/genética , Heterozigoto , Fenótipo , Retina , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética , Tomografia de Coerência Óptica/métodos , Fibras Nervosas , Neurônios Retinianos
6.
Molecules ; 28(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37241913

RESUMO

The interest in high hydrostatic pressure (HHP) is mostly focused on the inactivation of deleterious enzymes, considering the quality-related issues associated with enzymes in foods. However, more recently, HHP has been increasingly studied for several biotechnological applications, including the possibility of carrying out enzyme-catalyzed reactions under high pressure. This review aims to comprehensively present and discuss the effects of HHP on the kinetic catalytic action of enzymes and the equilibrium of the reaction when enzymatic reactions take place under pressure. Each enzyme can respond differently to high pressure, mainly depending on the pressure range and temperature applied. In some cases, the enzymatic reaction remains significantly active at high pressure and temperature, while at ambient pressure it is already inactivated or possesses minor activity. Furthermore, the effect of temperature and pressure on the enzymatic activity indicated a faster decrease in activity when elevated pressure is applied. For most cases, the product concentration at equilibrium under pressure increased; however, in some cases, hydrolysis was preferred over synthesis when pressure increased. The compiled evidence of the effect of high pressure on enzymatic activity indicates that pressure is an effective reaction parameter and that its application for enzyme catalysis is promising.


Assuntos
Pressão Hidrostática , Temperatura , Hidrólise , Catálise , Cinética
7.
Molecules ; 28(2)2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36677758

RESUMO

The quality standards for the export of chestnuts generate large quantities of rejected fruits, which require novel processing technologies for their safe industrial utilization. This study aimed to investigate the impact of high-pressure processing (HPP) and hydrothermal treatments (HT) on the physicochemical properties of rejected chestnut starch. Chestnuts were treated by HPP at 400, 500, and 600 MPa for 5 min and HT at 50 °C for 45 min. In general, all HPP treatments did not induce starch gelatinization, and their granules preserved the integrity and Maltese-cross. Moreover, starch granules' size and resistant starch content increased with the intensity of pressure. Native and HT chestnut starches were the most susceptible to digestion. HPP treatments did not affect the C-type crystalline pattern of native starch, but the crystalline region was gradually modified to become amorphous. HPP-600 MPa treated starch showed modified pasting properties and exhibited the highest values of peak viscosity. This study demonstrates for the first time that after HPP-600 MPa treatment, a novel chestnut starch gel structure is obtained. Moreover, HPP treatments could increase the slow-digesting starch, which benefits the development of healthier products. HPP can be considered an interesting technology to obtain added-value starch from rejected chestnut fruits.


Assuntos
Amilose , Amido , Amido/química , Amilose/química , Viscosidade , Nozes/química , Amido Resistente/análise
8.
Am J Hum Genet ; 105(4): 836-843, 2019 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-31564437

RESUMO

Osteogenesis imperfecta (OI) comprises a genetically heterogeneous group of skeletal fragility diseases. Here, we report on five independent families with a progressively deforming type of OI, in whom we identified four homozygous truncation or frameshift mutations in MESD. Affected individuals had recurrent fractures and at least one had oligodontia. MESD encodes an endoplasmic reticulum (ER) chaperone protein for the canonical Wingless-related integration site (WNT) signaling receptors LRP5 and LRP6. Because complete absence of MESD causes embryonic lethality in mice, we hypothesized that the OI-associated mutations are hypomorphic alleles since these mutations occur downstream of the chaperone activity domain but upstream of ER-retention domain. This would be consistent with the clinical phenotypes of skeletal fragility and oligodontia in persons deficient for LRP5 and LRP6, respectively. When we expressed wild-type (WT) and mutant MESD in HEK293T cells, we detected WT MESD in cell lysate but not in conditioned medium, whereas the converse was true for mutant MESD. We observed that both WT and mutant MESD retained the ability to chaperone LRP5. Thus, OI-associated MESD mutations produce hypomorphic alleles whose failure to remain within the ER significantly reduces but does not completely eliminate LRP5 and LRP6 trafficking. Since these individuals have no eye abnormalities (which occur in individuals completely lacking LRP5) and have neither limb nor brain patterning defects (both of which occur in mice completely lacking LRP6), we infer that bone mass accrual and dental patterning are more sensitive to reduced canonical WNT signaling than are other developmental processes. Biologic agents that can increase LRP5 and LRP6-mediated WNT signaling could benefit individuals with MESD-associated OI.


Assuntos
Chaperonas Moleculares/genética , Mutação , Osteogênese Imperfeita/genética , Animais , Feminino , Genes Recessivos , Células HEK293 , Humanos , Proteína-5 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Masculino , Camundongos , Linhagem , Fenótipo , Via de Sinalização Wnt
9.
Eur J Pediatr ; 181(7): 2809-2819, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35522316

RESUMO

Trisomy 18 is an autosomal chromosomal disorder characterized by the presence of an extra 18 chromosome. In the last decades, and as novel therapeutic options emerged, a paradigm shift on the treatments available to these children occurred, establishing the need to deepen the knowledge regarding the management/treatment of children diagnosed with trisomy 18. This retrospective cohort study sought to characterize the clinical path and survival of the children with the diagnosis of trisomy 18 followed in a tertiary pediatric hospital between 1995 and 2020. Medical records were reviewed, and epidemiological and clinical features and follow-up data were collected. Six patients were identified, two with mosaicism (33.3%) and four were female (66.7%). All had cardiovascular, cognitive, and physical development anomalies or minor congenital anomalies. Most presented neurological anomalies (n = 4, 66.7%) and feeding difficulties (n = 4, 66.7%). Four children (66.7%) required medical devices or equipment and all required chronic medication. Two children (33.3%) underwent surgical interventions. Four children (66.7%) were hospitalized in the last year of life. Three patients had a do not resuscitate order (50%) but only one child was referred to a pediatric palliative care team (16.7%). One-month, 1-year, and 10-year survival were 66.7% (n = 4), 33.3% (n = 2, both with mosaicism), and 16.7% (n = 1, with mosaicism) respectively. CONCLUSIONS: Knowledge of the multiple comorbidities and complex care needs of children with this syndrome is crucial. Every-day care and decisions about invasive treatments may raise ethical issues. Early referral to pediatric palliative care teams is essential to promote a holistic advanced care plan for both the patient and his family. WHAT IS KNOWN: • The increase in survival and the high morbimortality that trisomy 18 still entails demands a careful deliberation on the use of invasive treatment. WHAT IS NEW: • Recent studies show that the labels of "incompatible with life"/"lethal" are not adequate, establishing a need to change this mindset. • The development of pediatric palliative care teams in the last decade and early referral allow for an optimal individualized advanced care plan. Under-referral to pediatric palliative care teams persists and efforts must be made to increase awareness of their existence and role in patient care.


Assuntos
Cuidados Paliativos , Encaminhamento e Consulta , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos , Trissomia/diagnóstico , Síndrome da Trissomía do Cromossomo 18
10.
Graefes Arch Clin Exp Ophthalmol ; 260(9): 2859-2866, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35389060

RESUMO

PURPOSE: Retinitis pigmentosa (RP) corresponds to a group of inherited retinal disorders where progressive rod-cone degeneration is observed. Cystoid macular edema (CME) and vitreomacular interface disorders (VMID) are known to complicate the RP phenotype, challenging an age-old concept of retained central visual acuity. The reported prevalence of these changes varies greatly among different studies. We aim to describe the frequency of CME and VMID and identify predictors of these changes in a cohort of Caucasian patients with genetically solved syndromic (sRP) and non-syndromic RP (nsRP). METHODS: Cross-sectional study of patients with genetically solved sRP or nsRP. Genetic testing was clinically oriented in all probands and coordinated by a medical geneticist. The presence/absence of CME and VMIDs such as epiretinal membrane (ERM), vitreomacular traction (VMT), lamellar hole (LH), macular hole (MH), and macular pseudohole (MPH), and the integrity of the neurosensory retina and retinal pigment epithelium were evaluated in individual macular SD-OCT b-scans. Mixed-effects regression analysis models were used to identify significant predictors of BCVA, CME, and VMID. Significance was considered at α < 0.05. RESULTS: We included 250 eyes from 125 patients. Mean age was 44.9 ± 15.7 years and 55.2% were male. Eighty-eight patients had nsRP and 37 had sRP. Median BCVA was 0.5 (0.2-1.3) logMAR. CME was found in 17.1% of eyes, while ERM was found in 54.3% of eyes. The frequency of CME (p = 0.45) and ERM (p = 0.07) did not differ between sRP and nsRP patients, nor across different inheritance patterns. Mixed-effects univariate linear regression identified age (p = 0.04), cataract surgery (p < 0.01), and loss of integrity of outer retinal layers (p < 0.01) as significant predictors of lower visual acuity, while increased foveal thickness (p < 0.01) and the presence of CME (p = 0.04) were predictors of higher visual acuity. On mixed-effects multivariable analysis, only increased foveal thickness was significantly associated with better visual acuity (p < 0.01). CONCLUSION: We found that the burden of ERM and CME in RP patients is high, highlighting the importance of screening for these potentially treatable conditions to improve the quality of life of RP patients.


Assuntos
Membrana Epirretiniana , Edema Macular , Retinose Pigmentar , Estudos Transversais , Feminino , Humanos , Masculino , Qualidade de Vida , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual
11.
Graefes Arch Clin Exp Ophthalmol ; 260(4): 1405-1413, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34568954

RESUMO

PURPOSE: Sector retinitis pigmentosa (RP) is a rare form of rod-cone degeneration typically associated with mutations in the RHO gene. We describe six unrelated patients presenting with this atypical phenotype in association with biallelic mutations in EYS gene. METHODS: Multinational, multicentre cross-sectional case series. Patients with biallelic disease-causing variants in EYS and a clinical diagnosis of sector RP were recruited from specialized centres in Portugal and Brazil. All patients underwent a comprehensive ophthalmologic examination complemented by deep phenotyping. Peripheral blood samples were collected from all probands and available relatives for genetic analysis. Genetic counselling was provided to all subjects. RESULTS: Seven disease-causing variants (4 pathogenic; 3 likely pathogenic) were identified in 6 unrelated female patients. Best-corrected visual acuity ranged from 75 to 85 ETDRS letters. All eyes showed bilateral and symmetrical areas of outer retinal atrophy distributed along the inferior vascular arcades and extending temporally and/or nasally in a crescent-shaped pattern. On fundus autofluorescence (AF), a foveal-sparing curvilinear band of hyperAF encroaching the optic nerve head and extending temporally was seen in 4 patients. The remaining 2 presented bilateral and symmetrical patches of hypoAF inside crescent-shaped areas of hyperAF along the inferior temporal vascular arcade. Visual field testing revealed superior visual field defects of varying extents, always in close association with the fundus AF findings. CONCLUSIONS: Even though EYS has only recently been listed as a cause of the sector RP phenotype, we believe that this presentation is not infrequent and should be considered an important differential for sector RP.


Assuntos
Distrofias de Cones e Bastonetes , Retinose Pigmentar , Estudos Transversais , Análise Mutacional de DNA , Proteínas do Olho/genética , Feminino , Humanos , Mutação , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética
12.
Ophthalmologica ; 245(2): 134-143, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34695833

RESUMO

INTRODUCTION: The purpose of this study was to compare clinical/demographic functional testing and multimodal imaging features between genetically solved and genetically unsolved nonsyndromic retinitis pigmentosa (nsRP) patients. METHODS: A cross-sectional study was conducted at an inherited retinal dystrophies reference center. Consecutive patients with nsRP and available genetic testing results performed between 2018 and 2020 were included. Genetic testing was clinically oriented, and variants were classified according to the American College of Medical Genetics and Genomics. Only class IV or V variants were considered disease-causing. Clinical/demographic, functional, and imaging features were compared between genetically unsolved (G1) and genetically solved (G2) patients. RESULTS: A total of 175 patients (146 families) were included: 68 patients (59 families) in G1 and 107 patients (87 families) in G2. First symptoms <25 years, consanguinity, evidence for a particular inheritance pattern, and the absence of indicators for phenocopies were significantly more prevalent in G2. No significant differences were observed on best-corrected visual acuity. The visual field index and mean central retinal layer thickness were significantly higher in G1. The frequency of atypical features on multimodal imaging did not differ between groups. CONCLUSION: Individual clinical/demographic functional testing and multimodal imaging features should be considered when counseling patients about the probability of identifying disease-causing variants.


Assuntos
Retinose Pigmentar , Estudos Transversais , Demografia , Humanos , Imagem Multimodal , Mutação , Fenótipo , Retinose Pigmentar/diagnóstico , Retinose Pigmentar/genética
13.
Food Microbiol ; 105: 104031, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35473969

RESUMO

A new nonthermal food pasteurization approach is here presented for the first time, proposed to be called low-pressure long-time (LPLT) pasteurization or moderate pressure pasteurization (MPP) by hyperbaric inactivation (HI). To test this novel pasteurization process on raw milk, MPP by HI was carried out at three different pressure levels (150, 200 and 250 MPa), over 24 h, at naturally variable uncontrolled room temperature (≈20 °C) and compared with high pressure processing (HPP) at 600 MPa (one cycle for 90 s and a second cycle of 120 s) followed by storage under refrigeration for 21 days. Based on the results obtained, MPP at 250 MPa over 24 h caused higher microbial inactivation on total aerobic mesophiles (TAM), lactic acid bacteria (LAB) and Enterobacteriaceae (ENT) (of at least 2.2, 1.7 and 1.3 log CFU/mL, respectively) than HPP (1.1, 1.0 and 1.2 log CFU/mL, for the same microorganisms). Moreover, MPP showed a clear reduction of inoculated microorganisms to below the detection limit, in only 16 h for all pressures with reductions of at least 5.7, 5.4 and 5.5 for Listeria innocua, Salmonella senftenberg, and Escherichia coli, respectively. Additionally, during preservation under refrigeration, MPP samples (200 MPa and 250 MPa), maintained lower TAM/LAB/ENT compared to HPP, being the counts below the quantification/detection limit for at least 21 days for MPP by HI. MPP (200 MPa and 250 MPa) resulted also in counts below the detection limit for the inoculated microorganisms up to at least 21 days under refrigeration. The results of MPP by HI are very promising as a new nonthermal food pasteurization, since over 5 log reduction of vegetative bacteria were achieved, with counts maintained below the quantification/detection limit for at least 21 days under refrigeration.


Assuntos
Lactobacillales , Pasteurização , Animais , Microbiologia de Alimentos , Leite/microbiologia , Refrigeração , Temperatura
14.
Molecules ; 27(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36144653

RESUMO

Honey is a value-added product rich in several types of phenolic compounds, enzymes, and sugars recently explored in biomedical and food applications. Nevertheless, even though it has a low water activity (aW ≈ 0.65) that hinders the development of pathogenic and spoilage microorganisms, it is still prone to contamination by pathogenic microorganisms (vegetative and spores) and may constitute harm to special groups, particularly by immunosuppressed people and pregnant women. Thus, an efficient processing methodology needs to be followed to ensure microbial safety while avoiding 5-hydroxymethylfurfural (HMF) formation and browning reactions, with a consequent loss of biological value. In this paper, both thermal (pressure-assisted thermal processing, PATP) and nonthermal high-pressure processing (HPP), and another pressure-based methodology (hyperbaric storage, HS) were used to ascertain their potential to inactivate Bacillus subtilis endospores in honey and to study the influence of aW on the inactivation on this endospore. The results showed that PATP at 600 MPa/15 min/75 °C of diluted honey (52.9 °Brix) with increased aW (0.85 compared to ≈0.55, the usual honey aW) allowed for inactivating of at least 4.0 log units of B. subtilis spores (to below detection limits), while HS and HPP caused neither the germination nor inactivated spores (i.e., there was neither a loss of endospore resistance after heat shock nor endospore inactivation as a consequence of the storage methodology). PATP of undiluted honey even at harsh processing conditions (600 MPa/15 min/85 °C) did not impact the spore load. The results for diluted honey open the possibility of its decontamination by spores' inactivation for medical and pharmaceutical applications.


Assuntos
Bacillus subtilis , Mel , Feminino , Temperatura Alta , Humanos , Preparações Farmacêuticas , Gravidez , Esporos Bacterianos , Açúcares , Água
15.
Crit Rev Food Sci Nutr ; 61(12): 2078-2089, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32496815

RESUMO

From 2012, the preservation of food products under pressure has been increasingly studied and the knowledge acquired has enlarged since several food products have been studied at different storage conditions. This new food preservation methodology concept called Hyperbaric Storage (HS) has gain relevance due to its potential as a replacement or an improvement to the conventional cold storage processes, such as the traditional refrigeration (RF), or even frosting, from the energetic savings to the reduction of the carbon foot-print. Briefly, HS is capable to inhibit the microbial proliferation or its inactivation which results in the extension of the shelf-life of several food products when compared to RF. Moreover, the overall quality parameters seem not to be affected by HS, being the differences detected on samples over storage similar to lower when compared to the ones stored at RF. This review paper aims to gather data from all studies carried out so far regarding HS performance, mainly at room temperature on fruit juices, meat and fisheries, as well on dairy products and ready-to-eat meals. The HS advantages as a new food preservation methodology are presented and explained, being also discussed the industrial viability and environmental impact of this methodology, as well its limitations.


Assuntos
Armazenamento de Alimentos , Refrigeração , Microbiologia de Alimentos , Conservação de Alimentos , Carne/análise , Temperatura
16.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072026

RESUMO

Pineapple is consumed on a large scale around the world due to its appreciated sensorial characteristics. The industry of minimally processed pineapple produces enormous quantities of by-products (30-50%) which are generally undervalued. The end-of-life of pineapple by-products (PBP) can be replaced by reuse and renewal flows in an integrated process to promote economic growth by reducing consumption of natural resources and diminishing food waste. In our study, pineapple shell (PS) and pineapple core (PC), vacuum-packed separately, were subjected to moderate hydrostatic pressure (225 MPa, 8.5 min) (MHP) as abiotic stress to increase bromelain activity and antioxidant capacity. Pressurized and raw PBP were lyophilized to produce a stable powder. The dehydrated samples were characterized by the following methodologies: chemical and physical characterization, total phenolic compounds (TPC), antioxidant capacity, bromelain activity, microbiology, and mycotoxins. Results demonstrated that PBP are naturally rich in carbohydrates (66-88%), insoluble (16-28%) and soluble (2-4%) fiber, and minerals (4-5%). MHP was demonstrated to be beneficial in improving TPC (2-4%), antioxidant activity (2-6%), and bromelain activity (6-32%) without affecting the nutritional value. Furthermore, microbial and mycotoxical analysis demonstrated that powdered PC is a safe by-product. PS application is possible but requires previous decontamination to reduce the microbiological load.


Assuntos
Ananas/química , Ananas/fisiologia , Antioxidantes/química , Alimento Funcional/análise , Benzotiazóis/química , Compostos de Bifenilo/química , Bromelaínas/análise , Carboidratos/química , Técnicas de Química Analítica , Cor , Fibras na Dieta , Embalagem de Alimentos , Conservação de Alimentos , Liofilização , Frutas/química , Micotoxinas/química , Valor Nutritivo , Fenol/química , Picratos/química , Pós , Pressão , Ácidos Sulfônicos/química , Água/química
17.
Molecules ; 26(16)2021 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-34443372

RESUMO

Honey is a natural product rich in several phenolic compounds, enzymes, and sugars with antioxidant, anticarcinogenic, anti-inflammatory, and antimicrobial potential. Indeed, the development of honey-based adhesives for wound care and other biomedical applications are topics being widely investigated over the years. Some of the advantages of the use of honey for wound-healing solutions are the acceleration of dermal repair and epithelialization, angiogenesis promotion, immune response promotion and the reduction in healing-related infections with pathogenic microorganisms. This paper reviews the main role of honey on the development of wound-healing-based applications, the main compounds responsible for the healing capacity, how the honey origin can influence the healing properties, also highlighting promising results in in vitro and in vivo trials. The challenges in the use of honey for wound healing are also covered and discussed. The delivery methodology (direct application, incorporated in fibrous membranes and hydrogels) is also presented and discussed.


Assuntos
Mel , Cicatrização , Administração Tópica , Animais , Tecnologia Biomédica , Queimaduras/patologia , Humanos , Nanofibras/química
18.
J Sci Food Agric ; 101(9): 3975-3980, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33336437

RESUMO

BACKGROUND: Raw ewe's milk, as used to manufacture Serra da Estrela Protected Designation of Origin cheese, was pre-treated by high pressure processing (HPP), using previously optimized conditions (121 MPa for 30 min), aiming to evaluate its effect on milk technological properties for subsequent cheese production, namely the impact on resulting curd, whey and cheese throughout ripening. RESULTS: The cheese yield increased 10.4% as a result of milk pre-treated by HPP, which also yielded inactivation of beneficial microbial groups. After 60 days of ripening, both treated and control cheeses showed no significant differences (P ≥ 0.05) with respect to quantified microbial load or basic physicochemical quality parameters. CONCLUSION: HPP appears to be a promising non-thermal treatment for ewes' milk to inactivate contaminant bacteria but with no negative effect on lactic acid bacteria, which is very important for the unique characteristics of Serra da Estrela cheese. © 2020 Society of Chemical Industry.


Assuntos
Queijo/análise , Manipulação de Alimentos/métodos , Leite/química , Animais , Feminino , Fermentação , Manipulação de Alimentos/instrumentação , Lactobacillales/crescimento & desenvolvimento , Lactobacillales/metabolismo , Leite/microbiologia , Pressão , Ovinos
19.
J Sci Food Agric ; 101(1): 74-81, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32609872

RESUMO

BACKGROUND: The consumption of vegetable juices has increased due to their characteristics such as freshness/naturalness, high nutritional value, low in calories, and for being a convenient way of consuming bioactive compounds. High hydrostatic pressure (HPP), which has been mainly used to replace thermal processing, is now also being successfully applied as extraction technology to recover bioactive compounds from herbs. The present work aimed to evaluate the effect of supplementation of carrot juice with winter savory leaf aqueous extract on the final juice characteristics. RESULTS: The extract was added to raw carrot juice (1.0 mg mL-1 ), which was then submitted to HPP and stored for 15 days under refrigeration. Microbial analyses were performed during storage time, as also were analyzed the physicochemical properties such as pH, colour, bioactive compound concentration and antioxidant activity. Supplemented juices presented lower microbial counts than the non-supplemented ones, and, generally, did not present significant changes (P > 0.05) in pH or colour. Concerning the total phenolics and total flavonoids, as well as antioxidant activity, the values were generally higher (P < 0.05) in supplemented juices, which was proven by the high correlation found between total phenolics and ABTS●+ and FRAP assays. CONCLUSIONS: These data suggest that the addition of winter savory leaf extract in carrot juice treated with HPP can effectively improve microbial safety throughout refrigerated storage as well as antioxidant activity, without risking other characteristics of the juice, such as the colour or the acidity. © 2020 Society of Chemical Industry.


Assuntos
Daucus carota/química , Aditivos Alimentares/análise , Conservação de Alimentos/métodos , Sucos de Frutas e Vegetais/análise , Extratos Vegetais/análise , Satureja/química , Antioxidantes/análise , Manipulação de Alimentos/instrumentação , Manipulação de Alimentos/métodos , Concentração de Íons de Hidrogênio , Pressão Hidrostática , Valor Nutritivo , Folhas de Planta/química
20.
Compr Rev Food Sci Food Saf ; 20(6): 5393-5420, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34626076

RESUMO

Honey is a natural food of worldwide economic importance. Over the last decades, its potential for food, medical, cosmetical, and biotechnological applications has been widely explored. One of the major safety issues regarding such applications is its susceptibility to being contaminated with bacterial and fungi spores, including pathogenic ones, which may impose a hurdle to its consumption in a raw state. Another factor that makes this product particularly challenging relies on its high sugar content, which will lead to the formation of hydroxymethylfurfural (HMF) when heated (due to Maillard reactions). Moreover, honey's bioactivity is known to be affected when it goes through thermal processing due to its unstable and thermolabile components. Therefore, proper food processing methodologies are of utmost importance not only to ensure honey safety but also to provide a high-quality product with low content of HMF and preserved biological properties. As so, emerging food processing technologies have been employed to improve the safety and quality of raw honey, allowing, for example, to reduce/avoid the exposure time to high processing temperatures, with consequent impact on the formation of HMF. This review aims to gather the literature available regarding the use of conventional and emergent food processing technologies (both thermal and nonthermal food processing technologies) for honey decontamination, preservation/enhancement of honey biological activity, as well as the sensorial attributes.


Assuntos
Mel , Bactérias , Manipulação de Alimentos , Mel/análise , Temperatura Alta
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA