Effect of selected agents for ochratoxin A biocontrol on the colour, texture and volatile profile of dry-cured fermented sausages

BACKGROUND

Traditional dry-cured fermented sausages favour the growth of an autochthonous microbial population, which plays an important role in their sensory aspects. However, some moulds can produce mycotoxins such as ochratoxin A (OTA). The biocontrol agents (BCAs) Debaryomyces hansenii FHSCC 253H and Staphylococcus xylosus FHSCC Sx8 have been demonstrated to reduce OTA production in dry-cured meat products, but their influence in the sensory characteristics of sausages has to be tested. The aim of this study was to evaluate the effect of these BCAs on the colour, texture and volatile profile of dry-cured fermented sausages.

RESULTS

D. hansenii caused few differences in the tested parameters with respect to the control batch. S. xylosus modified the texture and colour, although the values found were within the range expected for dry-cured fermented sausages 'salchichón'. Additionally, the volatile profile revealed the potential antioxidant effect of both BCAs and their ability to produce compounds associated with the ripened aroma that could increase product acceptability.

CONCLUSION

The results indicate that there were no inconveniences in implementing both BCAs during the processing of dry-cured fermented sausages 'salchichón'. Moreover, D. hansenii FHSCC 253H could improve the volatile profile of this product. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Deciphering Staphylococcus xylosus and Staphylococcus equorum mode of action against Penicillium nordicum in a dry-cured ham model system

Penicillium nordicum is one of the major producers of ochratoxin A (OTA) in dry-cured ham. Staphylococcus xylosus Sx8 and Staphylococcus equorum Se31 have been previously proposed as biocontrol agents (BCAs) to prevent the OTA contamination, although their antifungal mode of action has not been established yet. Thus, the aim of this work was to elucidate their mode of action against P. nordicum in a dry-cured ham model system. For this, the effect of live cells, dead cells, and cell-free broth; the nutritional utilisation pattern, niche overlap index (NOI), interactions by dual-culture assays, antifungal effect of volatile compounds, OTA detoxification, and effect on fungal proteome were determined. No fungal growth was observed after 14 days of co-culture with live cells of each staphylococcus at 15 or 20 °C. However, such inhibition was not observed with either dead cells or extracellular extracts. The number of carbon sources utilised by P. nordicum was higher than those used by both cocci at 20 °C, whilst the opposite occurred at 15 °C. According to NOI, nutritional dominance depends on temperature, at 20 °C P. nordicum dominated the niche, but at 15 °C the mould is dominated by the BCAs. The volatile pattern generated by each coccus did not show antifungal effect, and both staphylococci failed to degrade or adsorb OTA. However, in the interaction assay, S. xylosus and S. equorum were able to decrease the fungal growth and its OTA production. In addition, proteomic analyses showed changes in the abundance of proteins related to the cell wall integrity (CWI), carbohydrate metabolism and the biosynthesis of secondary metabolites such as OTA. In conclusion, overall, the antagonistic effects of the two studied cocci against P. nordicum are greater at 15 °C than at 20 °C, being linked to competition for space and nutrients, triggering alterations in CWI pathway, OTA biosynthesis, and carbohydrate metabolism.

Perspectives on the Probiotic Potential of Indigenous Moulds and Yeasts in Dry-Fermented Sausages

The role of indigenous fungi in the appropriate development of sensory properties and the safety of dry-fermented sausages has been widely established. Nonetheless, their applications as probiotic agents have not been elucidated in such products yet, despite their promising functional features. Thus, it should be interesting to evaluate the probiotic potential of native Debaryomyces hansenii isolates from dry-fermented sausages and their application in the meat industry, because it is the most frequently isolated yeast species from these foodstuffs and its probiotic effects for animals as well as its possible probiotic activity for human beings have been demonstrated. Within the functional ability of foodborne yeasts, anti-inflammatory, antioxidant, antimicrobial, antigenotoxic, and immunomodulatory properties have been reported. Similarly, the use of dry-fermented sausages as vehicles for probiotic moulds remains a challenge because the survival and development of moulds in the gastrointestinal tract are still unknown. Nevertheless, some moulds have been isolated from faeces possibly from their spores as a form of resistance. Additionally, their beneficial effects on animals and humans, such as the decrease in lipid content and the anti-inflammatory activity, have been reported, although they seem to be more related to their postbiotic capacity due to the generated bioactive compounds with profunctional attributes than to their role as probiotics. Therefore, further studies providing knowledge useful for generating dry-fermented sausages with improved functionality are fully necessary.

Biocontrol of Pathogen Microorganisms in Ripened Foods of Animal Origin

Ripened foods of animal origin comprise meat products and dairy products, being transformed by the wild microbiota which populates the raw materials, generating highly appreciated products over the world. Together with this beneficial microbiota, both pathogenic and toxigenic microorganisms such as Listeria monocytogenes, Salmonella enterica, Staphylococcus aureus, Clostridium botulinum, Escherichia coli, Candida spp., Penicillium spp. and Aspergillus spp., can contaminate these products and pose a risk for the consumers. Thus, effective strategies to hamper these hazards are required. Additionally, consumer demand for clean label products is increasing. Therefore, the manufacturing sector is seeking new efficient, natural, low-environmental impact and easy to apply strategies to counteract these microorganisms. This review gathers different approaches to maximize food safety and discusses the possibility of their being applied or the necessity of new evidence, mainly for validation in the manufacturing product and its sensory impact, before being implemented as preventative measures in the Hazard Analysis and Critical Control Point programs.

Potential of Near Infrared Spectroscopy as a Rapid Method to Discriminate OTA and Non-OTA-Producing Mould Species in a Dry-Cured Ham Model System

The ripening process of dry-cured meat products is characterised by the development of fungi on the product's surface. This population plays a beneficial role, but, uncontrolled moulds represent a health risk, since some of them may produce mycotoxins, such as ochratoxin A (OTA). The aim of the present work is to assess the potential of near-infrared spectroscopy (NIRS) for the detection of OTA-producing mould species on dry-cured ham-based agar. The collected spectra were used to develop Support Vector Machines-Discriminant Analysis (SVM-DA) models by a hierarchical approach. Firstly, an SVM-DA model was tested to discriminate OTA and non-OTA producers; then, two models were tested to discriminate species among the OTA producers and the non-OTA producers. OTA and non-OTA-producing moulds were discriminated with 85% sensitivity and 86% specificity in the prediction. Furthermore, the SVM-DA model could differentiate non-OTA-producing species with a 95% sensitivity and specificity. Promising results were obtained for the prediction of the four OTA-producing species tested, with a 69% and 90% sensitivity and specificity, respectively. The preliminary approach demonstrated the high potential of NIR spectroscopy, coupled with Chemometrics, to be used as a real-time automated routine monitorization of dry-cured ham surfaces.

Selection and Evaluation of Staphylococcus xylosus as a Biocontrol Agent against Toxigenic Moulds in a Dry-Cured Ham Model System

Toxigenic moulds can develop on the surface of dry-cured meat products during ripening due to their ecological conditions, which constitutes a risk for consumers. A promising strategy to control this hazard is the use of antifungal microorganisms usually found in these foods. However, to date, the effectiveness of gram-positive catalase-positive cocci (GCC+) has not been explored. The aim of this work was to select GCC+ isolates with antifungal activity to study its effectiveness in a dry-cured ham model system at the environmental conditions reached during the ripening. Forty-five strains of GCC+ were evaluated and the isolate Staphylococcus xylosus Sx8 was selected to assess its efficacy at two different concentrations (106 and 104 cfu/mL) against Penicillium nordicum, Aspergillus flavus, Aspergillus parasiticus, and Penicillium griseofulvum at 15, 20, and 25 °C. The results showed that the inoculation of 106 cfu/mL of S. xylosus completely inhibited the growth of most fungi. In addition, in the presence of this strain at 104 cfu/mL, a significant reduction in fungal growth and mycotoxins production was observed at the three temperatures studied. In conclusion, S. xylosus Sx8 possesses great potential as a biological agent to control toxigenic moulds in dry-cured meat products.

Randomised, double-blind, placebo-controlled clinical trial for evaluating the efficacy of intracoronary injection of autologous bone marrow mononuclear cells in the improvement of the ventricular function in patients with idiopathic dilated myocardiopathy: a study protocol

Background

Cellular therapies have been increasingly applied to diverse human diseases. Intracoronary infusion of bone marrow-derived mononuclear cells (BMMNC) has demonstrated to improve ventricular function after acute myocardial infarction. However, less information is available about the role of BMMNC therapy for the treatment of dilated myocardiopathies (DCs) of non-ischemic origin. This article presents the methodological description of a study aimed at investigating the efficacy of intracoronary injection of autologous BMMNCs in the improvement of the ventricular function of patients with DC.

Methods

This randomised, placebo-controlled, double-blinded phase IIb clinical trial compares the improvement on ventricular function (measured by the changes on the ejection fraction) of patients receiving the conventional treatment for DC in combination with a single dose of an intracoronary infusion of BMMNCs, with the functional recovery of patients receiving placebo plus conventional treatment. Patients assigned to both treatment groups are monitored for 24 months. This clinical trial is powered enough to detect a change in Left Ventricular Ejection Fraction (LVEF) equal to or greater than 9%, although an interim analysis is planned to re-calculate sample size.

Discussion

The study protocol was approved by the Andalusian Coordinating Ethics Committee for Biomedical Research (Comité Coordinador de Ética en Investigación Biomédica de Andalucia), the Spanish Medicines and Medical Devices Agency (Agencia Española de Medicamentos y Productos Sanitarios), and is registered at the EU Clinical Trials Register (EudraCT: 2013–002015-98). The publication of the trial results in scientific journals will be performed in accordance with the applicable regulations and guidelines to clinical trials.

Trial registration

ClinicalTrials.gov Identifier NCT02033278 (First Posted January 10, 2014): https://clinicaltrials.gov/ct2/show/NCT02033278; EudraCT number: 2013–002015-98, EU CT Register: https://www.clinicaltrialsregister.eu/ctr-search/search?query=2013-002015-98. Trial results will also be published according to the CONSORT statement at conferences and reported peer-reviewed journals.

Persistent natural acidification drives major distribution shifts in marine benthic ecosystems

Ocean acidification is receiving increasing attention because of its potential to affect marine ecosystems. Rare CO2 vents offer a unique opportunity to investigate the response of benthic ecosystems to acidification. However, the benthic habitats investigated so far are mainly found at very shallow water (less than or equal to 5 m depth) and therefore are not representative of the broad range of continental shelf habitats. Here, we show that a decrease from pH 8.1 to 7.9 observed in a CO2 vent system at 40 m depth leads to a dramatic shift in highly diverse and structurally complex habitats. Forests of the kelp Laminaria rodriguezii usually found at larger depths (greater than 65 m) replace the otherwise dominant habitats (i.e. coralligenous outcrops and rhodolith beds), which are mainly characterized by calcifying organisms. Only the aragonite-calcifying algae are able to survive in acidified waters, while high-magnesium-calcite organisms are almost completely absent. Although a long-term survey of the venting area would be necessary to fully understand the effects of the variability of pH and other carbonate parameters over the structure and functioning of the investigated mesophotic habitats, our results suggest that in addition of significant changes at species level, moderate ocean acidification may entail major shifts in the distribution and dominance of key benthic ecosystems at regional scale, which could have broad ecological and socio-economic implications.

[Cognitive and neuropsychiatric disorders in Parkinson's disease]

INTRODUCTION

In Parkinson's disease there are patients with isolated and multiple cognitive impairment, and their cognitive performance ranges from normal to an advanced degree of dementia. Most patients present an executive deficit, either in isolation or combined with other cognitive disorders, which is considered to be the most characteristic aspect of the disease, and 30-40% of those affected will end up with a clinically-defined dementia.

DEVELOPMENT

The presence of a mild cognitive disorder in patients with Parkinson means that the risk of dementia appearing at some time during the development of the disease is high. The dementia associated with Parkinson's disease is specifically related with neuropsychiatric signs and symptoms, which may have three possible explanations: disorders affecting the mesolimbic pathways, diffuse limbic and cortical compromise, or associated Alzheimer-type phenomenology. Psychotic episodes tend to present more often in patients with dopaminergic treatment and the clinical spectrum of Parkinson-related psychosis covers visual illusions, visual-audio-olfactory hallucinations, delirium and severe paranoid hallucinatory psychosis. All the antiparkinsonian drugs can give rise to hallucinations and psychosis, but the dopamine agonists are the ones with the greatest capacity to do so.

CONCLUSIONS

In managing these problems, it is crucial for prevention as well as diagnosis and treatment to be carried out as soon as they are detected. Doses of antiparkinsonian drugs must be reduced, although this is not usually enough, and so it will be necessary to associate atypical antipsychotics, which act mainly on 5-HT receptors and, in most cases, do not produce D2 blockage.

[Sleep and women]

INTRODUCTION

There is a strong link between female sex hormones and sleep. This implies the existence of sex differences both in the structure of sleep as in the incidence of various sleep disorders.

AIM

To review the changes in the pattern of sleep experienced by women along different stages of their life cycle (fertile period, menstruation, pregnancy, menopause and postmenopause), as well as the most frequent sleeping pathologies in which there exist more gender differences (insomnia, obstructive sleep apnea syndrome, restless legs syndrome and narcolepsy).

DEVELOPMENT

About normal sleeping has been reported a higher quality of it, in women compared with men (increased sleeping time, reduced sleep onset latency, and a greater efficiency of sleeping), but they frequently complain of sleep problems. Moreover, different stages in the life of women are associated with significant physiological and hormonal changes that favour the disruption of normal sleep pattern and by this way, possibly, increase risk to suffer sleep disorders.

CONCLUSIONS

The reasons that underlie in gender differences in sleeping disorders are attributed to differences in normal sleep pattern, in the clinical manifestations and risk factors for sleep disorders, and in the results and optimal dose of treatments.

[A case-control study of the influence of the smoking behaviour in multiple sclerosis]

INTRODUCTION

Several epidemiological studies have demonstrated that there is a genetic factor of susceptibility in Multiple Sclerosis (MS) and that the environmental factors play an important important role in their development. Smoking is among the environment factors studied. In fact, several studies have established a relationship between smoking and multiple sclerosis, although most of them did not find significant results or found that these were contradictory.

OBJECTIVE

To evaluate the influence of the smoking habit on the risk of suffering MS.

METHODS

This was a case-control matched study with 138 patients diagnosed of MS according to the McDonald criteria who were paired with the same number of controls of the same gender, residents in the same city and having the same age +/-2 years. Demographic data, smoking status (never, always smokers, ex-smokers), Kurtzke disability status scale (EDSS) and type of MS were collected.

RESULTS

Out of a total of 138 MS patients (93 women, 43 men), 110 had relapsing-remitting MS, 20 secondary progressive MS and 7 primary progressive MS. Most of the patients were smokers and ex-smokers (63%). In the control group, only the 41,3% were smokers/ex-smokers. Moreover, the age of onset for smoking was earlier in the case group.

CONCLUSION

Being a smoker/ex-smoker implies a 27% greater risk of developing MS compared to those who have never smoked. This risk is statistically significant for women but not for men due to the low number of them in the sample.

[Morbidity in hospital admission for stroke]

INTRODUCTION

In spite of advances in the prevention and treatment of ischemic vascular disease, this continues to be one of the main causes of disablement and prolonged hospitalization in developed countries. Also, hospitalization itself leads to complications which have a negative effect on the morbi-mortality of these patients during the time spent in hospital.

OBJECTIVE

We decided to study the effect of systemic complications during the period of hospital stay, on the functional recovery of patients which ictusl.

MATERIAL AND METHODS

A prospective study was made of 47 patients admitted to our unit for neurological deficit of more than 24 hours evolution and of cerebrovascular aetiology. Functional recovery was evaluated by means of the index of Barthel on discharge and after a period of 3 months with respect to the degree of neurological involvement (Canadian scale on admission), glycemia on admission, time spent in hospital and the occurrence of systemic complications in hospital.

RESULTS

These were no differences between the groups of patients with and without systemic complications regarding age, glycemia and Canadian scale on admission. Nor wes there any difference between the groups regarding the number of patients with significant deterioration of their neurological condition (decrease > 20% in the EC). Functional recovery on hospital discharge was worse in the group with systemic complications (IB: 43.05 +/- 34.1: as compared with IB: 72.8 +/- 22.7 in the group without complications). This difference persisted after 3 months.

CONCLUSIONS

Systemic complications related to hospitalization have a negative effect on the functional recovery of patient with ictus and also prolong the time spent in hospital.

[Cytomorphological study of the cerebrospinal fluid. II. Leukemias and lymphomas (author's transl)]

A cytological study of the cerebrospinal fluid from 25 patients with acute leukemias and five patients with malignant lymphomas (Hodgkin's disease and non-Hodgkin's lymphoma) has been performed. All patients had clinical manifestations of central nervous system involvement at the time of lumbar puncture. Cytological abnormalities were observed in 13 out of the 30 samples examined (positivity: 44 percent). The group of 17 patients with lymphoblastic leukemia accounted for the highest cytological positivity (12 our of 17 cases --70.5 percent--). Cerebrospinal fluid from eight patients with acute myeloblastic leukemia and from four patients with Hodgkin's disease was normal. Numerous cell atypias were found in a case of lymphocytic lymphoma. The importance of systematic cytological study of the cerebrospinal fluid in patients with leukemia in order to prevent recurrences and to control intrathecal administration of cytostatics and/or radiotherapy is stressed.