Safety demonstration of microbial species Risk assessment of specific microbial strains for use in the food chain

Gli alimenti fermentati sono stati consumati per più di 10 000 anni. La fermentazione degli alimenti è probabilmente una delle più antiche tecnologie alimentari implementate dall'uomo, sebbene le conoscenze scientifiche alla base del suo ruolo e dei meccanismi di azione siano state studiate solo negli ultimi 150 anni. Attualmente, si stima che i prodotti alimentari fermentati rappresentino un terzo della nostra assunzione di cibo. La microbiologia alimentare ha fornito molte risposte dietro i ruoli, le modalità di azione, la nutrizione e gli effetti sulla salute degli alimenti fermentati. Tuttavia, uno dei principali temi di preoccupazione rimane la dimostrazione di sicurezza delle colture alimentari microbiche. Più di recente, alla fine del 2017, la Cina ha bloccato l'importazione di formaggi dall'Europa, a causa della presenza di colture alimentari microbiche non presenti nell'elenco cinese positivo 2010. Anche l'Europa (Biohazard Panel – Qualified Presumption of Safety) e gli Stati Uniti (GRAS – Generalmente riconosciuto come sicuro) dispongono rispettivamente di una procedura per la valutazione del rischio microbico delle specie microbiche aggiunte volontariamente alla catena alimentare. L'International Dairy Federation (IDF), in collaborazione con l'associazione europea Food and Feed Cultures, ha lavorato negli ultimi 20 anni su un inventario delle specie microbiche con proprietà tecnologiche negli alimenti fermentati. Durante il ciclo di 3 anni, abbiamo proseguito il lavoro dell'IDF, aggiornando due volte l'inventario, nel 2018 con l'introduzione di specie alimentari microbiche da prodotti alimentari indigeni asiatici, e nel 2021 considerando le varie matrici alimentari e l'utilizzo alimentare riconducibili a un singole specie microbiche. Pertanto, abbiamo concentrato il lavoro sul ruolo delle colture alimentari e sulla bioconservazione degli alimenti, come inizialmente suggerito dalla logica iniziale della dimostrazione delle colture alimentari dell'IDF. A dimostrazione del concetto dell'approccio della dimostrazione di sicurezza di una coltura alimentare, il lavoro analitico è stato svolto su una raccolta di alimenti e isolati clinici della specie microbica Weissella confusa, che possono essere sia isolati in prodotti da forno (Europa), piante a base di prodotti derivati ​​(Asia) e con studi preliminari per il suo utilizzo nei prodotti lattiero-caseari. Il presente studio proporrà una dimostrazione di sicurezza delle specie microbiche per il loro uso attraverso l'inoculazione in una matrice alimentare per l'uso nella catena alimentare. Ha lo scopo di evitare scambi commerciali tra paesi in cui non è possibile stabilire una storia di utilizzo sicuro per un prodotto alimentare fermentato autoctono sul mercato internazionale, oltre a evitare le insidie ​​dell'incrocio di fermentazione, modificando al contempo la matrice alimentare in cui viene effettuata la fermentazione alimentare , e possibilmente omettendo le attività dannose dei metaboliti.Fermented foods have been consumed for more than 10 000 years. Food fermentation is probably one of the oldest food technologies implemented by man, although the scientific knowledge behind its role and mechanisms of actions have only been studied in the past 150 years. Presently, fermented food products are estimated to represent a third of our food intake. Food Microbiology has provided many answers behind the roles, modes of action, nutrition and health effects of fermented foods. One of the major topics of concern nevertheless remains the safety demonstration of the microbial food cultures. Most recently, in late 2017, China blocked the importation of cheeses from Europe, due to the presence of microbial food cultures not present in the Chinese 2010 positive list. Europe (Biohazard Panel – Qualified Presumption of Safety) and United States (GRAS – Generally Recognized as Safe) also have a procedure in place respectively for the microbial risk assessment of microbial species voluntarily added to the food chain. The International Dairy Federation (IDF), in collaboration with the European Food and Feed Cultures association, has been working for the past 20 years on an inventory of microbial species with technological properties in fermented foods. During the 3 years cycle, we have continued the work of the IDF, updating twice the inventory, in 2018 with the introduction of microbial food species from indigenous Asian food products, and in 2021 while considering the various food matrices and food usage attributable to a single microbial species. As such, we have focused the work on the role of food cultures and food bio-preservation, as initially suggested by the initial rationale of demonstration of food cultures of the IDF. As a proof of concept of the approach of safety demonstration of a food culture, the analytical work has been done of a collection of food and clinical isolates of the microbial species Weissella confusa, which can be both isolated in bakery products (Europe), plant-based products (Asia) and with preliminary studies for its used in dairy food products. The present study will propose a safety demonstration of microbial species for its use through inoculation in a food matrix for use in the food chain. It is aimed to avoid barrier trades between countries where a history of safe use cannot be established for an indigenous fermented food products on international market, as well as avoiding the pitfalls of cross over fermentation, while changing the food matrix where the food fermentation is done, and possibly omitting deleterious metabolites activities

Estudo in vitro e in vivo da eficácia anti leishmaniótica de terapêutica combinada de Diminazene e Artesunate contra Leishmania donovani em camundongos Balb/c

The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be 2.28 ± 0.24 µg/mL while those of Dim and Art were 9.16 ± 0.3 µg/mL and 4.64 ± 0.48 µg/mL respectively. The IC50 for Amphot B was 0.16 ± 0.32 µg/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly (p < 0.001) reduced parasite burden in the spleen as compared to the single drug treatments given at the same dosages. Although parasite burden was slightly lower (p < 0.05) in the Amphot B group than in the Dim-Art treatment group, the present study demonstrates the positive advantage and the potential use of the combined therapy of Dim-Art over the constituent drugs, Dim or Art when used alone. Further evaluation is recommended to determine the most efficacious combination ratio of the two compounds.A atividade in vitro e in vivo de Diminazene (Dim), Artezunate (Art) e a combinação Dim e Art (Dim-Art) contra Leishmania donovani foi comparada com a droga de referência Anfotericina B. IC50 da Dim-Art foi 2,28 ± 0,24 µg/mL enquanto aquelas de Dim e Art foram 9,16 ± 0,3 µg/mL e 4,64 ± 0,48 µg/mL respectivamente. O IC50 da Anfotericina B foi 0,16 ± 0,32 µg/mL contra a fase estacionária de promastigotas. A avaliação in vivo do modelo de L. donovani em camundongos Balb/c indicou que os tratamentos com a terapêutica de drogas combinadas em doses de 12,5 mg/kg por 28 dias consecutivos significantemente (p < 0,001) reduziu a carga parasitária no baço quando comparada a tratamentos com uma única droga dada nas mesmas dosagens. Embora a carga parasitária tenha sido levemente mais baixa (p < 0.05) no grupo Anfotericina B quando comparada com o grupo tratado Dim-Art, o estudo presente demonstra a vantagem positiva do uso potencial da terapêutica combinada Dim-Art sobre drogas como Dim ou Art quando usadas isoladamente. Posterior avaliação é recomendada para determinar a média de combinação mais eficaz dos dois compostos

La morfología y la realidad profesional

Abordamos el concepto de forma, no sólo en su versión geométrica, sino también como entidad significativa, concebida como un producto cultural, histórico e inserto en un ámbito social que posibilita su existencia. Al considerar al objeto de diseño industrial como signo, reconocemos en él la posibilidad de sustentar un significado compartido y a partir de allí transformarse además, en vehículo para la proyección de un mensaje

In vitro and in vivo antileishmanial efficacy of a combination therapy of diminazene and artesunate against Leishmania donovani in BALB /c mice

The in vitro and in vivo activity of diminazene (Dim), artesunate (Art) and combination of Dim and Art (Dim-Art) against Leishmania donovani was compared to reference drug; amphotericin B. IC50 of Dim-Art was found to be $2.28 \pm 0.24 \mu$ g/mL while those of Dim and Art were $9.16 \pm 0.3 \mu$ g/mL and $4.64 \pm 0.48 \mu$ g/mL respectively. The IC50 for Amphot B was $0.16 \pm 0.32 \mu$ g/mL against stationary-phase promastigotes. In vivo evaluation in the L. donovani BALB/c mice model indicated that treatments with the combined drug therapy at doses of 12.5 mg/kg for 28 consecutive days significantly ($p < 0.001$) reduced parasite burden in the spleen as compared to the single drug treatments given at the same dosages. Although parasite burden was slightly lower ($p < 0.05$) in the Amphot B group than in the Dim-Art treatment group, the present study demonstrates the positive advantage and the potential use of the combined therapy of Dim-Art over the constituent drugs, Dim or Art when used alone. Further evaluation is recommended to determine the most efficacious combination ratio of the two compounds.Comment: 4 Pages, 3 Figure

Fluorescence in situ hybridization method using a peptide nucleic acid probe for identification of Lactobacillus spp. in milk samples

Lactobacillus species constitute one of the dominant and beneficial bacteria in our body and are used in developed countries as a microbial adjuvant. Identification of these probiotic bacteria is traditionally performed by culture-based techniques. However, such methods are very time-consuming and can give inaccurate results, especially when Lactobacillus is present in mixed bacterial complex communities. Our study aimed to accurately identify Lactobacillus spp. using a novel Peptide Nucleic Acid (PNA) Fluorescence In Situ Hibridization (FISH) probe. The probe (Lac663) was tested on 36 strains belonging to different Lactobacillus species and on 20 strains of other bacterial species. The sensitivity and specificity of the method were 100% (95% confidence interval (CI), 88.0 to 100.0%) and 95.0% (95% CI, 73.1 to 99.7%), respectively. Additionally, we tested the applicability of the method on milk samples added with Lactobacillus strains at probiotic range concentrations and others taxonomically related bacteria, as well as pathogenic bacteria. The Lac663 probe bound exclusively to Lactobacillus strains and the described PNA-FISH method was capable of directly quantifying Lactobacillus spp. in concentrations at which these potential probiotic bacteria are considered to have an effective benefit on human health.This work was supported by European Union funds (FEDER/COMPETE) and by national funds (FCT) under the project with reference FCOMP-01-0124-FEDER-008991 (PTDC/BIA-MIC/098228/2008. Antonio Machado acknowledges the FCT individual fellowship-SFRH/BD/62375/2009. However, it is important to refer that FCT did not have any role in the design of the experiments or manuscript writing

Diet rapidly and reproducibly alters the human gut microbiome

Long-term diet influences the structure and activity of the trillions of microorganisms residing in the human gut1–5, but it remains unclear how rapidly and reproducibly the human gut microbiome responds to short-term macronutrient change. Here, we show that the short-term consumption of diets composed entirely of animal or plant products alters microbial community structure and overwhelms inter-individual differences in microbial gene expression. The animal-based diet increased the abundance of bile-tolerant microorganisms (Alistipes, Bilophila, and Bacteroides) and decreased the levels of Firmicutes that metabolize dietary plant polysaccharides (Roseburia, Eubacterium rectale, and Ruminococcus bromii). Microbial activity mirrored differences between herbivorous and carnivorous mammals2, reflecting trade-offs between carbohydrate and protein fermentation. Foodborne microbes from both diets transiently colonized the gut, including bacteria, fungi, and even viruses. Finally, increases in the abundance and activity of Bilophila wadsworthia on the animal-based diet support a link between dietary fat, bile acids, and the outgrowth of microorganisms capable of triggering inflammatory bowel disease6. In concert, these results demonstrate that the gut microbiome can rapidly respond to altered diet, potentially facilitating the diversity of human dietary lifestyles

The forgotten role of food cultures

Fermentation is one of if not the oldest food processing technique, yet it is still an emerging field when it comes to its numerous mechanisms of action and potential applications. The effect of microbial activity on the taste, bioavailability and preservation of the nutrients and the different food matrices has been deciphered by the insights of molecular microbiology. Among those roles of fermentation in the food chain, biopreservation remains the one most debated. Presumably because it has been underestimated for quite a while, and only considered - based on a food safety and technological approach - from the toxicological and chemical perspective. Biopreservation is not considered as a traditional use, where it has been by design - but forgotten - as the initial goal of fermentation. The 'modern' use of biopreservation is also slightly different from the traditional use, due mainly to changes in cooling of food and other ways of preservation, Extending shelf life is considered to be one of the properties of food additives, classifying - from our perspective - biopreservation wrongly and forgetting the role of fermentation and food cultures. The present review will summarize the current approaches of fermentation as a way to preserve and protect the food, considering the different way in which food cultures and this application could help tackle food waste as an additional control measure to ensure the safety of the food