Aldo Corsetti - Profile on Academia.edu (original) (raw)

Papers by Aldo Corsetti

Research paper thumbnail of In Lactobacillus pentosus, the olive brine adaptation genes are required for biofilm formation

In Lactobacillus pentosus, the olive brine adaptation genes are required for biofilm formation

International Journal of Food Microbiology, 2016

Lactobacillus pentosus is one of the few lactic acid bacteria (LAB) species capable of surviving ... more Lactobacillus pentosus is one of the few lactic acid bacteria (LAB) species capable of surviving in olive brine, and thus desirable during table olive fermentation. We have recently generated mutants of the efficient strain L. pentosus C11 by transposon mutagenesis and identified five mutants unable to survive and adapt to olive brine conditions. Since biofilm formation represents one of the main bacterial strategy to survive in stressful environments, in this study, the capacity of adhesion and formation of biofilm on olive skin was investigated for this strain and five derivative mutants which are interrupted in metabolic genes (enoA1 and gpi), and in genes of unknown function ("oba" genes). Confocal microscopy together with bacteria count revealed that the sessile state represented the prevailing L. pentosus C11 life-style during table olive fermentation. The characterization of cell surface properties showed that mutants present less hydrophobic and basic properties than the wild type (WT). In fact, their ability to adhere to both abiotic (polystyrene plates) and biotic (olive skin) surfaces was lower than that of the WT. Confocal microscopy revealed that mutants adhered sparsely to the olive skin instead of building a thin, multilayer biofilm. Moreover, RT-qPCR showed that the three genes enoA1, gpi and obaC were upregulated in the olive biofilm compared to the planktonic state. Thus enoA1, gpi and "oba" genes are necessary in L. pentosus to form an organized biofilm on the olive skin.

Research paper thumbnail of Liquid Sourdough Fermentation

Liquid Sourdough Fermentation

Handbook of Plant-Based Fermented Food and Beverage Technology, Second Edition, 2012

Research paper thumbnail of Citation

Citation

This article was submitted to Food

Research paper thumbnail of Aspetti microbiologici, chimico-fisici e contenuto di amine biogene in Pecorino di farindola prodotto con caglio suino, capretto e vitello

Aspetti microbiologici, chimico-fisici e contenuto di amine biogene in Pecorino di farindola prodotto con caglio suino, capretto e vitello

Research paper thumbnail of LACTOBACILLUSspp. | Lactobacillus plantarum

LACTOBACILLUSspp. | Lactobacillus plantarum

Research paper thumbnail of Lactic Acid Bacteria Exopolysaccharides Producers: A Sustainable Tool for Functional Foods

Foods, 2021

Lactic acid bacteria (LAB) used in the food industry, mainly for the production of dairy products... more Lactic acid bacteria (LAB) used in the food industry, mainly for the production of dairy products, are able to synthetize exopolysaccharides (EPS). EPS play a central role in the assessment of rheological and sensory characteristics of dairy products since they positively influence texture and organoleptic properties. Besides these, EPS have gained relevant interest for pharmacological and nutraceutical applications due to their biocompatibility, non-toxicity and biodegradability. These bioactive compounds may act as antioxidant, cholesterol-lowering, antimicrobial and prebiotic agents. This review provides an overview of exopolysaccharide-producing LAB, with an insight on the factors affecting EPS production, their dairy industrial applications and health benefits.

Research paper thumbnail of Food-borne Lactiplantibacillus plantarum protect normal intestinal cells against inflammation by modulating reactive oxygen species and IL-23/IL-17 axis

Scientific Reports, 2020

Food-associated Lactiplantibacillus plantarum (Lpb. plantarum) strains, previously classified as ... more Food-associated Lactiplantibacillus plantarum (Lpb. plantarum) strains, previously classified as Lactobacillus plantarum, are a promising strategy to face intestinal inflammatory diseases. Our study was aimed at clarifying the protective role of food-borne Lpb. plantarum against inflammatory damage by testing the scavenging microbial ability both in selected strains and in co-incubation with normal mucosa intestinal cells (NCM460). Here, we show that Lpb. plantarum endure high levels of induced oxidative stress through partially neutralizing reactive oxygen species (ROS), whereas they elicit their production when co-cultured with NCM460. Moreover, pre-treatment with food-borne Lpb. plantarum significantly reduce pro-inflammatory cytokines IL-17F and IL-23 levels in inflamed NCM460 cells. Our results suggest that food-vehicled Lpb. plantarum strains might reduce inflammatory response in intestinal cells by directly modulating local ROS production and by triggering the IL-23/IL-17 axi...

Research paper thumbnail of Health-Promoting Role of Lactiplantibacillus plantarum Isolated from Fermented Foods

Microorganisms, 2021

Fermentation processes have been used for centuries for food production and preservation. Besides... more Fermentation processes have been used for centuries for food production and preservation. Besides the contribution of fermentation to food quality, recently, scientific interest in the beneficial nature of fermented foods as a reservoir of probiotic candidates is increasing. Fermented food microbes are gaining attention for their health-promoting potential and for being genetically related to human probiotic bacteria. Among them, Lactiplantibacillus (Lpb.) plantarum strains, with a long history in the food industry as starter cultures in the production of a wide variety of fermented foods, are being investigated for their beneficial properties which are similar to those of probiotic strains, and they are also applied in clinical interventions. Food-associated Lpb. plantarum showed a good adaptation and adhesion ability in the gastro-intestinal tract and the potential to affect host health through various beneficial activities, e.g., antimicrobial, antioxidative, antigenotoxic, anti-...

Research paper thumbnail of Immunomodulation of J774A.1 Murine Macrophages by Lactiplantibacillus plantarum Strains Isolated From the Human Gastrointestinal Tract and Fermented Foods

Frontiers in Microbiology, 2021

Lactobacillus plantarum species (recently re-named Lactiplantibacillus (Lpb.) plantarum subsp. pl... more Lactobacillus plantarum species (recently re-named Lactiplantibacillus (Lpb.) plantarum subsp. plantarum) can be isolated from both either the mammalian gut or specific fermented foods where they may be present at high concentrations. Whilst Lpb. plantarum strains have been proposed as potential probiotic candidates, the ability of resident strains consumed in fermented foods to interact with the host is unclear. The main objective of this study was to investigate the cellular location and ability of three different food-borne Lpb. plantarum strains isolated from different sources (table olives and cheese) to modulate the immune response of a murine macrophage-like cell line (J774A.1). For that purpose, macrophages were exposed to the three different Lpb. plantarum strains for 24 h and the expression of a panel of genes involved in the immune response, including genes encoding pattern-recognition receptors (TLRs and NLRs) and cytokines was evaluated by qRT-PCR. We also utilized chem...

Research paper thumbnail of Table olives microbiota

Table olives fermentation is the result of a complex set of dynamics involving diverse microbial ... more Table olives fermentation is the result of a complex set of dynamics involving diverse microbial populations such as lactic acid bacteria, yeasts and moulds. Their metabolic activities determine the characteristics such as flavour, texture and safety of the final product. This chapter offers an overview on the main microbiota characterizing table olives and their role during fermentation.

Research paper thumbnail of The proteolytic system of Lactobacillus sanfrancisco CB1: purification and characterization of a proteinase, a dipeptidase, and an aminopeptidase

Applied and Environmental Microbiology, 1996

A cell envelope 57-kDa proteinase, a cytoplasmic 65-kDa dipeptidase, and a 75-kDa aminopeptidase ... more A cell envelope 57-kDa proteinase, a cytoplasmic 65-kDa dipeptidase, and a 75-kDa aminopeptidase were purified from Lactobacillus sanfrancisco CB1 sourdough lactic acid bacterium by sequential fast protein liquid chromatography steps. All of the enzymes are monomers. The proteinase was most active at pH 7.0 and 40 degrees C, while aminopeptidase and dipeptidase had optima at pH 7.5 and 30 to 35 degrees C. Relatively high activities were observed at the pH and temperature of the sourdough fermentation. The proteinase is a serine enzyme. Urea-polyacrylamide gel electrophoresis of digest of alpha s1- and beta-caseins showed differences in the pattern of peptides released by the purified proteinase and those produced by crude preparations of the cell envelope proteinases of Lactobacillus delbrueckii subsp. bulgaricus B397 and Lactococcus lactis subsp. lactis SK11. Reversed-phase fast protein liquid chromatography of gliadin digests showed a more-complex peptide pattern produced by the p...

Research paper thumbnail of Table Olives More than a Fermented Food

Foods, 2020

Table olives are one of the oldest vegetable fermented foods in the Mediterranean area. Beside th... more Table olives are one of the oldest vegetable fermented foods in the Mediterranean area. Beside their economic impact, fermented table olives represent also an important healthy food in the Mediterranean diet, because of their high content of bioactive and health-promoting compounds. However, olive fermentation is still craft-based following traditional processes, which can lead to a not fully predictable final product with the risk of spontaneous alterations. Nowadays, food industries have to face consumer demands for safe and healthy products. This review offers an overview about the main technologies used for olive fermentation and the role of lactic acid bacteria and yeasts characterizing this niche during the fermentation. Particular attention is offered to the selection and use of microorganisms as starter cultures to fasten and improve the safety of table olives. The development and implementation of multifunctional starter cultures in order to obtain heath-oriented table oliv...

Research paper thumbnail of Corrigendum: Changes in Polyphenolic Concentrations of Table Olives (cv. Itrana) Produced Under Different Irrigation Regimes During Spontaneous or Inoculated Fermentation

Frontiers in Microbiology, 2020

Research paper thumbnail of Changes in Polyphenolic Concentrations of Table Olives (cv. Itrana) Produced Under Different Irrigation Regimes During Spontaneous or Inoculated Fermentation

Frontiers in Microbiology, 2018

Irrigation is widely used for the production of table olives because it increases fruit size and ... more Irrigation is widely used for the production of table olives because it increases fruit size and yield. However, irrigation also determines less accumulation of total phenols, an increase in water content, a decrease of firmness, lower concentrations of soluble sugars in the mesocarp, thus positively or negatively affecting the fermentation process for the production of table olives. In this study we tested the hypothesis that green fruits of cultivar Itrana obtained by different irrigation regimes had different phenolic concentration that responded differentially to spontaneous or inoculated fermentation. Fruits were harvested from two orchards in the Latina province of Latium, Italy, which had been irrigated with different volumes of water during the growing season to compare the evolution of spontaneous and inoculated fermentation processes. We measured fruit characteristics at harvest, changes in the concentrations of secoiridoids and lignans, and main microbial groups abundance during fermentation. At harvest and during fermentation the concentration of phenolic compounds was higher in fruits sampled from trees that had received less water in the field. Differences were observed between spontaneous and inoculated fermentations, with a prevalence of lactic acid bacteria (LAB) in inoculated samples. In particular, oleuropein concentration completely disappeared only from samples inoculated with the two selected strains used as starters. The inoculum with selected LAB positively influenced the fermentation process of green olives, whereas the irrigation regime previously experienced by trees did not alter fermentation.

Research paper thumbnail of Adhesion Properties of Food-Associated Lactobacillus plantarum Strains on Human Intestinal Epithelial Cells and Modulation of IL-8 Release

Frontiers in Microbiology, 2018

Food-associated microbes can reach the gut as viable cells and interact with the human host provi... more Food-associated microbes can reach the gut as viable cells and interact with the human host providing potential health benefits. In this study, we evaluated the impact on cell viability and the adhesion ability of 22 Lactobacillus plantarum strains, mainly isolated from fermented foods, on a Normal-derived Colon Mucosa cell line. Furthermore, due to the presence of mucus layer on the gut epithelium, we also investigated whether the mucin could affect the microbial adhesion property. Our results demonstrated that all the strains displayed a strong ability to adhere to host cells, showing a straindependent behavior with preference for cell edges, that resulted not to be affected by the presence of mucin. Based on interleukin-8 release of intestinal cells induced by some Lb. plantarum strains, our data suggest a potential cross-talk with the host immune system as unconventional property of these food-associated microbes.

Research paper thumbnail of Inhibition of Proteolytic Enzymes from Pseudomonas fluorescens ATCC 948 and Angiotensin I-Converting Enzyme by Peptides from Zein, Hordein, and Gluten Hydrolysates

Journal of Food Protection, 1997

Peptides inhibitory to partially purified endopeptidase and crude proteinase from Pseudomonas flu... more Peptides inhibitory to partially purified endopeptidase and crude proteinase from Pseudomonas fluorescens ATCC 948 were isolated from tryptic hydrolysates of zein and hordein by reversed-phase fast protein liquid chromatography and identified by sequencing. The sequences are Ser-Ala-Tyr-Pro-Gly-Gln-Ile-Thr-Ser-Asn and Gln-Val-Ser-Leu-Asn-Ser-Gly-Tyr-Tyr for peptides from zein and hordein, respectively. Inhibitions of >85% and from >50 to >85% were determined on endopeptidase and proteinase by peptides from zein and hordein. Ki values ranged from 4 to 32 μM. The same peptides also showed inhibition of the angiotensin I-converting enzyme. The concentrations of peptides providing 50% inhibition of angiotensin I-converting enzyme were 7 and 23 μM for the decapeptide and nonapeptide, respectively. Other fractions containing peptides with less inhibitory activity were detected in the zein as well as in the gluten tryptic digests.

Research paper thumbnail of Editorial: Microbial Food Safety along the Dairy Chain

Frontiers in Microbiology, 2017

Research paper thumbnail of Adhesion properties and surface hydrophobicity of Pichia manshurica strains isolated from organic wines

LWT, 2017

This study focuses on the determination of microorganisms present in spoiled bottled wines of a M... more This study focuses on the determination of microorganisms present in spoiled bottled wines of a Montepulciano d'Abruzzo organic wine and establish the source of this contamination. The yeasts belonging to Pichia manshurica species were genetically characterized by PFGE, and tested for their resistance to potassium metabisulphite and some cleaning agents determining the minimum inhibitory concentrations (MIC) and biofilms formation in YPD and pasteurized must. PFGE analysis revealed the presence of 2 karyotypes with 3 or 4 bands. The most effective detergent was the alkaline powder one, while the less active was the peracetic acid based sanitizing agent. MIC values for potassium metabisulphite ranged from 100 to 200 ppm. Regarding adhesion properties all strains showed a certain degree of hydrophobicity, as revealed by the affinity for hexadecane and decane, and were able to form biofilm on polystyrene plates: sessile cells reached values of 7.85 log cfu/mL in YPD and 6.95 log cfu/mL in must. All strains formed MAT structures and an air-liquid biofilm. This paper shows that organic wine can be subjected to contamination driven by not very resistant strains. Moreover, membrane filters used for wine sterilization act as a vector of wine contamination.

Research paper thumbnail of La biodiversità microbica in relazione ad alcune produzioni della regione Umbria: formaggio pecorino e “mozzarella” fior di latte

La biodiversità microbica in relazione ad alcune produzioni della regione Umbria: formaggio pecorino e “mozzarella” fior di latte

Research paper thumbnail of Enzimi, esopolisaccaridi e batteriocine

Enzimi, esopolisaccaridi e batteriocine

Research paper thumbnail of In Lactobacillus pentosus, the olive brine adaptation genes are required for biofilm formation

In Lactobacillus pentosus, the olive brine adaptation genes are required for biofilm formation

International Journal of Food Microbiology, 2016

Lactobacillus pentosus is one of the few lactic acid bacteria (LAB) species capable of surviving ... more Lactobacillus pentosus is one of the few lactic acid bacteria (LAB) species capable of surviving in olive brine, and thus desirable during table olive fermentation. We have recently generated mutants of the efficient strain L. pentosus C11 by transposon mutagenesis and identified five mutants unable to survive and adapt to olive brine conditions. Since biofilm formation represents one of the main bacterial strategy to survive in stressful environments, in this study, the capacity of adhesion and formation of biofilm on olive skin was investigated for this strain and five derivative mutants which are interrupted in metabolic genes (enoA1 and gpi), and in genes of unknown function ("oba" genes). Confocal microscopy together with bacteria count revealed that the sessile state represented the prevailing L. pentosus C11 life-style during table olive fermentation. The characterization of cell surface properties showed that mutants present less hydrophobic and basic properties than the wild type (WT). In fact, their ability to adhere to both abiotic (polystyrene plates) and biotic (olive skin) surfaces was lower than that of the WT. Confocal microscopy revealed that mutants adhered sparsely to the olive skin instead of building a thin, multilayer biofilm. Moreover, RT-qPCR showed that the three genes enoA1, gpi and obaC were upregulated in the olive biofilm compared to the planktonic state. Thus enoA1, gpi and "oba" genes are necessary in L. pentosus to form an organized biofilm on the olive skin.

Research paper thumbnail of Liquid Sourdough Fermentation

Liquid Sourdough Fermentation

Handbook of Plant-Based Fermented Food and Beverage Technology, Second Edition, 2012

Research paper thumbnail of Citation

Citation

This article was submitted to Food

Research paper thumbnail of Aspetti microbiologici, chimico-fisici e contenuto di amine biogene in Pecorino di farindola prodotto con caglio suino, capretto e vitello

Aspetti microbiologici, chimico-fisici e contenuto di amine biogene in Pecorino di farindola prodotto con caglio suino, capretto e vitello

Research paper thumbnail of LACTOBACILLUSspp. | Lactobacillus plantarum

LACTOBACILLUSspp. | Lactobacillus plantarum

Research paper thumbnail of Lactic Acid Bacteria Exopolysaccharides Producers: A Sustainable Tool for Functional Foods

Foods, 2021

Lactic acid bacteria (LAB) used in the food industry, mainly for the production of dairy products... more Lactic acid bacteria (LAB) used in the food industry, mainly for the production of dairy products, are able to synthetize exopolysaccharides (EPS). EPS play a central role in the assessment of rheological and sensory characteristics of dairy products since they positively influence texture and organoleptic properties. Besides these, EPS have gained relevant interest for pharmacological and nutraceutical applications due to their biocompatibility, non-toxicity and biodegradability. These bioactive compounds may act as antioxidant, cholesterol-lowering, antimicrobial and prebiotic agents. This review provides an overview of exopolysaccharide-producing LAB, with an insight on the factors affecting EPS production, their dairy industrial applications and health benefits.

Research paper thumbnail of Food-borne Lactiplantibacillus plantarum protect normal intestinal cells against inflammation by modulating reactive oxygen species and IL-23/IL-17 axis

Scientific Reports, 2020

Food-associated Lactiplantibacillus plantarum (Lpb. plantarum) strains, previously classified as ... more Food-associated Lactiplantibacillus plantarum (Lpb. plantarum) strains, previously classified as Lactobacillus plantarum, are a promising strategy to face intestinal inflammatory diseases. Our study was aimed at clarifying the protective role of food-borne Lpb. plantarum against inflammatory damage by testing the scavenging microbial ability both in selected strains and in co-incubation with normal mucosa intestinal cells (NCM460). Here, we show that Lpb. plantarum endure high levels of induced oxidative stress through partially neutralizing reactive oxygen species (ROS), whereas they elicit their production when co-cultured with NCM460. Moreover, pre-treatment with food-borne Lpb. plantarum significantly reduce pro-inflammatory cytokines IL-17F and IL-23 levels in inflamed NCM460 cells. Our results suggest that food-vehicled Lpb. plantarum strains might reduce inflammatory response in intestinal cells by directly modulating local ROS production and by triggering the IL-23/IL-17 axi...

Research paper thumbnail of Health-Promoting Role of Lactiplantibacillus plantarum Isolated from Fermented Foods

Microorganisms, 2021

Fermentation processes have been used for centuries for food production and preservation. Besides... more Fermentation processes have been used for centuries for food production and preservation. Besides the contribution of fermentation to food quality, recently, scientific interest in the beneficial nature of fermented foods as a reservoir of probiotic candidates is increasing. Fermented food microbes are gaining attention for their health-promoting potential and for being genetically related to human probiotic bacteria. Among them, Lactiplantibacillus (Lpb.) plantarum strains, with a long history in the food industry as starter cultures in the production of a wide variety of fermented foods, are being investigated for their beneficial properties which are similar to those of probiotic strains, and they are also applied in clinical interventions. Food-associated Lpb. plantarum showed a good adaptation and adhesion ability in the gastro-intestinal tract and the potential to affect host health through various beneficial activities, e.g., antimicrobial, antioxidative, antigenotoxic, anti-...

Research paper thumbnail of Immunomodulation of J774A.1 Murine Macrophages by Lactiplantibacillus plantarum Strains Isolated From the Human Gastrointestinal Tract and Fermented Foods

Frontiers in Microbiology, 2021

Lactobacillus plantarum species (recently re-named Lactiplantibacillus (Lpb.) plantarum subsp. pl... more Lactobacillus plantarum species (recently re-named Lactiplantibacillus (Lpb.) plantarum subsp. plantarum) can be isolated from both either the mammalian gut or specific fermented foods where they may be present at high concentrations. Whilst Lpb. plantarum strains have been proposed as potential probiotic candidates, the ability of resident strains consumed in fermented foods to interact with the host is unclear. The main objective of this study was to investigate the cellular location and ability of three different food-borne Lpb. plantarum strains isolated from different sources (table olives and cheese) to modulate the immune response of a murine macrophage-like cell line (J774A.1). For that purpose, macrophages were exposed to the three different Lpb. plantarum strains for 24 h and the expression of a panel of genes involved in the immune response, including genes encoding pattern-recognition receptors (TLRs and NLRs) and cytokines was evaluated by qRT-PCR. We also utilized chem...

Research paper thumbnail of Table olives microbiota

Table olives fermentation is the result of a complex set of dynamics involving diverse microbial ... more Table olives fermentation is the result of a complex set of dynamics involving diverse microbial populations such as lactic acid bacteria, yeasts and moulds. Their metabolic activities determine the characteristics such as flavour, texture and safety of the final product. This chapter offers an overview on the main microbiota characterizing table olives and their role during fermentation.

Research paper thumbnail of The proteolytic system of Lactobacillus sanfrancisco CB1: purification and characterization of a proteinase, a dipeptidase, and an aminopeptidase

Applied and Environmental Microbiology, 1996

A cell envelope 57-kDa proteinase, a cytoplasmic 65-kDa dipeptidase, and a 75-kDa aminopeptidase ... more A cell envelope 57-kDa proteinase, a cytoplasmic 65-kDa dipeptidase, and a 75-kDa aminopeptidase were purified from Lactobacillus sanfrancisco CB1 sourdough lactic acid bacterium by sequential fast protein liquid chromatography steps. All of the enzymes are monomers. The proteinase was most active at pH 7.0 and 40 degrees C, while aminopeptidase and dipeptidase had optima at pH 7.5 and 30 to 35 degrees C. Relatively high activities were observed at the pH and temperature of the sourdough fermentation. The proteinase is a serine enzyme. Urea-polyacrylamide gel electrophoresis of digest of alpha s1- and beta-caseins showed differences in the pattern of peptides released by the purified proteinase and those produced by crude preparations of the cell envelope proteinases of Lactobacillus delbrueckii subsp. bulgaricus B397 and Lactococcus lactis subsp. lactis SK11. Reversed-phase fast protein liquid chromatography of gliadin digests showed a more-complex peptide pattern produced by the p...

Research paper thumbnail of Table Olives More than a Fermented Food

Foods, 2020

Table olives are one of the oldest vegetable fermented foods in the Mediterranean area. Beside th... more Table olives are one of the oldest vegetable fermented foods in the Mediterranean area. Beside their economic impact, fermented table olives represent also an important healthy food in the Mediterranean diet, because of their high content of bioactive and health-promoting compounds. However, olive fermentation is still craft-based following traditional processes, which can lead to a not fully predictable final product with the risk of spontaneous alterations. Nowadays, food industries have to face consumer demands for safe and healthy products. This review offers an overview about the main technologies used for olive fermentation and the role of lactic acid bacteria and yeasts characterizing this niche during the fermentation. Particular attention is offered to the selection and use of microorganisms as starter cultures to fasten and improve the safety of table olives. The development and implementation of multifunctional starter cultures in order to obtain heath-oriented table oliv...

Research paper thumbnail of Corrigendum: Changes in Polyphenolic Concentrations of Table Olives (cv. Itrana) Produced Under Different Irrigation Regimes During Spontaneous or Inoculated Fermentation

Frontiers in Microbiology, 2020

Research paper thumbnail of Changes in Polyphenolic Concentrations of Table Olives (cv. Itrana) Produced Under Different Irrigation Regimes During Spontaneous or Inoculated Fermentation

Frontiers in Microbiology, 2018

Irrigation is widely used for the production of table olives because it increases fruit size and ... more Irrigation is widely used for the production of table olives because it increases fruit size and yield. However, irrigation also determines less accumulation of total phenols, an increase in water content, a decrease of firmness, lower concentrations of soluble sugars in the mesocarp, thus positively or negatively affecting the fermentation process for the production of table olives. In this study we tested the hypothesis that green fruits of cultivar Itrana obtained by different irrigation regimes had different phenolic concentration that responded differentially to spontaneous or inoculated fermentation. Fruits were harvested from two orchards in the Latina province of Latium, Italy, which had been irrigated with different volumes of water during the growing season to compare the evolution of spontaneous and inoculated fermentation processes. We measured fruit characteristics at harvest, changes in the concentrations of secoiridoids and lignans, and main microbial groups abundance during fermentation. At harvest and during fermentation the concentration of phenolic compounds was higher in fruits sampled from trees that had received less water in the field. Differences were observed between spontaneous and inoculated fermentations, with a prevalence of lactic acid bacteria (LAB) in inoculated samples. In particular, oleuropein concentration completely disappeared only from samples inoculated with the two selected strains used as starters. The inoculum with selected LAB positively influenced the fermentation process of green olives, whereas the irrigation regime previously experienced by trees did not alter fermentation.

Research paper thumbnail of Adhesion Properties of Food-Associated Lactobacillus plantarum Strains on Human Intestinal Epithelial Cells and Modulation of IL-8 Release

Frontiers in Microbiology, 2018

Food-associated microbes can reach the gut as viable cells and interact with the human host provi... more Food-associated microbes can reach the gut as viable cells and interact with the human host providing potential health benefits. In this study, we evaluated the impact on cell viability and the adhesion ability of 22 Lactobacillus plantarum strains, mainly isolated from fermented foods, on a Normal-derived Colon Mucosa cell line. Furthermore, due to the presence of mucus layer on the gut epithelium, we also investigated whether the mucin could affect the microbial adhesion property. Our results demonstrated that all the strains displayed a strong ability to adhere to host cells, showing a straindependent behavior with preference for cell edges, that resulted not to be affected by the presence of mucin. Based on interleukin-8 release of intestinal cells induced by some Lb. plantarum strains, our data suggest a potential cross-talk with the host immune system as unconventional property of these food-associated microbes.

Research paper thumbnail of Inhibition of Proteolytic Enzymes from Pseudomonas fluorescens ATCC 948 and Angiotensin I-Converting Enzyme by Peptides from Zein, Hordein, and Gluten Hydrolysates

Journal of Food Protection, 1997

Peptides inhibitory to partially purified endopeptidase and crude proteinase from Pseudomonas flu... more Peptides inhibitory to partially purified endopeptidase and crude proteinase from Pseudomonas fluorescens ATCC 948 were isolated from tryptic hydrolysates of zein and hordein by reversed-phase fast protein liquid chromatography and identified by sequencing. The sequences are Ser-Ala-Tyr-Pro-Gly-Gln-Ile-Thr-Ser-Asn and Gln-Val-Ser-Leu-Asn-Ser-Gly-Tyr-Tyr for peptides from zein and hordein, respectively. Inhibitions of >85% and from >50 to >85% were determined on endopeptidase and proteinase by peptides from zein and hordein. Ki values ranged from 4 to 32 μM. The same peptides also showed inhibition of the angiotensin I-converting enzyme. The concentrations of peptides providing 50% inhibition of angiotensin I-converting enzyme were 7 and 23 μM for the decapeptide and nonapeptide, respectively. Other fractions containing peptides with less inhibitory activity were detected in the zein as well as in the gluten tryptic digests.

Research paper thumbnail of Editorial: Microbial Food Safety along the Dairy Chain

Frontiers in Microbiology, 2017

Research paper thumbnail of Adhesion properties and surface hydrophobicity of Pichia manshurica strains isolated from organic wines

LWT, 2017

This study focuses on the determination of microorganisms present in spoiled bottled wines of a M... more This study focuses on the determination of microorganisms present in spoiled bottled wines of a Montepulciano d'Abruzzo organic wine and establish the source of this contamination. The yeasts belonging to Pichia manshurica species were genetically characterized by PFGE, and tested for their resistance to potassium metabisulphite and some cleaning agents determining the minimum inhibitory concentrations (MIC) and biofilms formation in YPD and pasteurized must. PFGE analysis revealed the presence of 2 karyotypes with 3 or 4 bands. The most effective detergent was the alkaline powder one, while the less active was the peracetic acid based sanitizing agent. MIC values for potassium metabisulphite ranged from 100 to 200 ppm. Regarding adhesion properties all strains showed a certain degree of hydrophobicity, as revealed by the affinity for hexadecane and decane, and were able to form biofilm on polystyrene plates: sessile cells reached values of 7.85 log cfu/mL in YPD and 6.95 log cfu/mL in must. All strains formed MAT structures and an air-liquid biofilm. This paper shows that organic wine can be subjected to contamination driven by not very resistant strains. Moreover, membrane filters used for wine sterilization act as a vector of wine contamination.

Research paper thumbnail of La biodiversità microbica in relazione ad alcune produzioni della regione Umbria: formaggio pecorino e “mozzarella” fior di latte

La biodiversità microbica in relazione ad alcune produzioni della regione Umbria: formaggio pecorino e “mozzarella” fior di latte

Research paper thumbnail of Enzimi, esopolisaccaridi e batteriocine

Enzimi, esopolisaccaridi e batteriocine