Maria Calasso | University of Bari Italy (original) (raw)

Papers by Maria Calasso

Research paper thumbnail of Causal relationship between microbial ecology dynamics and proteolysis during manufacture and ripening of protected designation of origin (PDO) cheese Canestrato Pugliese

Applied and environmental microbiology, 2014

Pyrosequencing of the 16S rRNA gene, community-level physiological profiles determined by the use... more Pyrosequencing of the 16S rRNA gene, community-level physiological profiles determined by the use of Biolog EcoPlates, and proteolysis analyses were used to characterize Canestrato Pugliese Protected Designation of Origin (PDO) cheese. The number of presumptive mesophilic lactococci in raw ewes' milk was higher than that of presumptive mesophilic lactobacilli. The numbers of these microbial groups increased during ripening, showing temporal and numerical differences. Urea-PAGE showed limited primary proteolysis, whereas the analysis of the pH 4.6-soluble fraction of the cheese revealed that secondary proteolysis increased mainly from 45 to 75 days of ripening. This agreed with the concentration of free amino acids. Raw ewes' milk was contaminated by several bacterial phyla: Proteobacteria (68%; mainly Pseudomonas), Firmicutes (30%; mainly Carnobacterium and Lactococcus), Bacteroidetes (0.05%), and Actinobacteria (0.02%). Almost the same microbial composition persisted in the...

Research paper thumbnail of Manufacture of Italian Caciotta-type cheeses with adjuncts and attenuated adjuncts of selected non-starter lactobacilli

Selected Lactobacillus paracasei FC2-5, Lactobacillus casei LC01 and Lactobacillus curvatus 2770 ... more Selected Lactobacillus paracasei FC2-5, Lactobacillus casei LC01 and Lactobacillus curvatus 2770 were used for cheese making as adjunct cultures (AC) or attenuated adjunct cultures (AAC). AAC were obtained by sonication treatment. Italian Caciotta-type cheeses were manufactured on an industrial plant scale, including control cheese (CC) without AC, and ripening was lasted 60 days at 10 °C. AAC did not increase the

Research paper thumbnail of The antimicrobial peptide pheromone Plantaricin A increases antioxidant defenses of human keratinocytes and modulates the expression of filaggrin, involucrin, β-defensin 2 and tumor necrosis factor-α genes

Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesiz... more Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesized chemically and used as a pure peptide or synthesized biologically using Lactobacillus plantarum DC400 co-cultured with Lactobacillus sanfranciscensis DPPMA174. Cell-free supernatant (CFS) was used as a crude PlnA preparation. As estimated using the 3-(4,5-dimethyl-2-yl)-2,5-diphenyltetrazolium bromide and the 2',7'-dichlorofluorescein diacetate assays, both PlnA preparations increased the antioxidant defenses of human NCTC 2544 keratinocytes. PlnA (10 μg/ml) had a higher activity than hyaluronic acid or 125 μg/ml α-tocopherol. Effects on the transcriptional regulation of filaggrin (FLG), involucrin (IVL), hyaluronan synthase (HAS2), human β-defensin-2 (HBD-2) and tumor necrosis factor-alpha (TNF-α) genes were assayed. Compared with the control, expression of the FLG gene in NCTC 2544 cells increased in cells treated with hyaluronic acid, 1 or 10 μg/ml PlnA. Compared with the control, the level of IVL gene expression increased in NCTC 2544 cells treated with 10 μg/ml PlnA. No significant difference was found between the level of the HAS2 gene expressed by control cells and cells treated with PlnA. Compared with chemically synthesized PlnA, the up-regulation of the HBD-2 gene by CFS was higher. Compared with the control, expression of TNF-α decreased in NCTC 2544 cells after treatment with 1 or 10 μg/ml of chemically synthesized PlnA. In contrast, the level of TNF-α was highest in the presence of 10 μg/ml CFS-PlnA. These findings suggest that the PlnA was positively sensed by human keratinocytes, promoting antioxidant defenses, barrier functions and antimicrobial activity of the skin.

Research paper thumbnail of Plantaricin A synthesized by Lactobacillus plantarum induces in vitro proliferation and migration of human keratinocytes and increases the expression of TGF-β1, FGF7, VEGF-A and IL-8 genes

Peptides, 2011

This work showed the effect of pheromone plantaricin A (PlnA) on the proliferation and migration ... more This work showed the effect of pheromone plantaricin A (PlnA) on the proliferation and migration of the human keratinocytes NCTC 2544. PlnA was chemically synthesized and used as pure peptide or biologically synthesized during co-cultivation of Lactobacillus plantarum DC400 and Lactobacillus sanfranciscensis DPPMA174. The cell-free supernatant (CFS) was used as the crude preparation containing PlnA. The inductive effect of PlnA on the proliferation of NCTC 2544 cells was higher than that found for hyaluronic acid, a well known skin protective compound. As shown by scratch assay and image analyses, PlnA enhanced the migration of NCTC 2544 cells. Compared to the basal serum free medium (control), the highest inductive effect was found using 10μg/ml of chemically synthesized PlnA. Similar results (P>0.05) were found for CFS. In agreement, the percentage of the starting scratch area was decreased after treatment (24h) with PlnA. The expression of transforming growth factor-β1 (TGF-β1), keratinocyte growth factor 7 (FGF7), vascular endothelial growth factor (VEGF-A), and interleukin-8 (IL-8) genes was affected by PlnA. Compared to control, TGF-β1 gene was under expressed in the first 4h of treatments and up-regulated after 8-24h. On the contrary, FGF7 gene was strongly up-regulated in the first 4h of treatments. Compared to control, VEGF-A and IL-8 genes were always up-regulated during the 4-24h from scratching. Since capable of promoting the proliferation and migration of the human keratinocytes and of stimulating IL-8 cytokine, the use of PlnA for dermatological purposes should be considered.

Research paper thumbnail of Effect of lactose on gut microbiota and metabolome of infants with cow’s milk allergy

Pediatric Allergy and Immunology, 2012

Research paper thumbnail of Proteomics of the bacterial cross-talk by quorum sensing

Journal of Proteomics, 2011

Words such as language and behavior are frequently used to depict "quorum sensing" (QS) in the li... more Words such as language and behavior are frequently used to depict "quorum sensing" (QS) in the literature. Simplifying the concept, language and cross-talk between bacteria, and between bacteria and animal or plants hosts determine the behavior (e.g., beneficial or pathogenic effects). Genomics and transcriptomics were the principal approaches used to study the multiple mechanisms of QS. Nevertheless, sequencing of genomes paved the way for another approach which consists on comparative and functional proteomics. This review aims at describing how the proteomic dictionary translates: (i) the languages (N-acyl-L-homoserine lactones, AHL; autoinducing peptide, AIP; autoinducer-2, AI-2) used by bacteria to communicate; (ii) signals of QS which induce various phenotypes (e.g., virulence, biofilm maturation); (iii) cross-talk between lactic acid bacteria within various food ecosystems (e.g. sourdough and fermented milk); (iv) probiotic messages at intra-and inter-species and interkingdom levels; and (v) words for quorum quenching (QQ).

Research paper thumbnail of Fermentation and proteome profiles of Lactobacillus plantarum strains during growth under food-like conditions

Journal of Proteomics, 2014

and sharing with colleagues.

Research paper thumbnail of NADP-glutamate dehydrogenase activity in nonstarter lactic acid bacteria: effects of temperature, pH and NaCl on enzyme activity and expression

Journal of Applied Microbiology, 2010

Research paper thumbnail of Proteomic Analysis by Two-Dimensional Gel Electrophoresis and Starch Characterization of Triticum turgidum L. var. durum Cultivars for Pasta Making

Journal of Agricultural and Food Chemistry, 2008

Criteria for durum wheat quality are continuously evolving in response to market pressure and con... more Criteria for durum wheat quality are continuously evolving in response to market pressure and consumer's preference. Specific attributes of durum wheat for different end products require more rapid and objective means to grade and classify wheat parcels based on processing potential. A total of 10 durum wheat cultivars were compared for compositional, protein, and starch characteristics. Mean values for the gross composition differed for total protein, gluten, and starch. Two-dimensional electrophoresis (2DE) analysis showed the proteome diversity among the cultivars. As shown by the principal component analysis (PCA) applied to 2DE data of gliadin and glutenin fractions, cultivars differed mainly from the number of proteins and levels of protein expression. As determined by the rapid viscoanalyzer (RVA), swelling power, starch damage, amylose content, and starch pasting properties of 10 cultivars differed significantly. 2DE fingerprinting and amylose content seemed to distinguish specific cultivars being useful tools for selecting suitable durum wheat cultivars for pasta making.

Research paper thumbnail of Use of sourdough fermentation and mixture of wheat, chickpea, lentil and bean flours for enhancing the nutritional, texture and sensory characteristics of white bread

International Journal of Food Microbiology, 2014

This study aimed at investigating the addition of legume (chickpea, lentil and bean) flours to wh... more This study aimed at investigating the addition of legume (chickpea, lentil and bean) flours to wheat flour bread. Type I sourdough containing legumes or wheat-legume flours were prepared and propagated (back slopped) in laboratory, according to traditional protocols that are routinely used for making typical Italian breads. Based on kinetic of acidification and culture-dependent data, the wheat-legume sourdough was further characterized and selected for bread making. As determined by RAPD-PCR and partial sequencing of 16S rDNA gene analyses, lactic acid bacteria in wheat-legume sourdough included Lactobacillus plantarum, Lactobacillus sanfranciscensis, Leuconostoc mesenteroides, Lactobacillus fermentum, Weissella cibaria, Lactobacillus pentosus, Lactobacillus coryneformis, Lactobacillus rossiae, Lactobacillus brevis, Lactobacillus parabuchneri and Lactobacillus paraplantarum. Two breads containing 15% (w/w) of legume (chickpea, lentil and bean) flours were produced using selected wheat-legume sourdough (WLSB) and traditional wheat sourdough (WSB). Compared to wheat yeasted bread (WYB), the level of total free amino acids (FAA) was higher in WSB and WLSB. Phytase and antioxidant activities were the highest in WLSB. Compared to bread WYB, the addition of legume flours decreased the in vitro protein digestibility (IVPD) (WYB versus WSB). However, the dough fermentation with WSLB favored an increase of IVPD. According to the levels of carbohydrates, dietary fibers and resistant starch, WSB and WLSB showed lower values of hydrolysis index (HI) compared to WYB. As showed by texture and image analyses and sensory evaluation of breads, a good acceptability was found for WSB and, especially, WLSB breads.

Research paper thumbnail of Selection and use of autochthonous multiple strain cultures for the manufacture of high-moisture traditional Mozzarella cheese

International Journal of Food Microbiology, 2008

Lactobacillus plantarum 18A, Lactobacillus helveticus 2B, Lactobacillus delbrueckii subsp. lactis... more Lactobacillus plantarum 18A, Lactobacillus helveticus 2B, Lactobacillus delbrueckii subsp. lactis 20F, Streptococcus thermophilus 22C, Enterococcus faecalis 32C and Enterococcus durans 16E were the most acidifying strains within 146 isolates for natural whey starters. The effect of media and temperature on 2 autochthonous multiple strain cultures (AMSI: 18A, 2B, 20F and 22C, 32C and 16E and AMSII: 18A, 2B, 20F and 22C) was studied. Genomic analysis showed a constant cell numbers for AMSII during 16 days of propagation in whey milk. Mozzarella cheese was made by using AMSII, commercial starter (CS) or citric acid (DA). Compared to other cheeses, the DA had a lower level of protein, ash, Ca, free amino acids and a higher level of moisture. Based on confocal laser scanning microscopy analysis, AMSII cheese showed the lowest microstructural variations during the period of storage compared to other cheeses. All the sensory attributes were scored highest for AMSII cheese. ASMII extend the shelf-life to ca. 12−15 days instead of the 5−7 days of traditional high-moisture Mozzarella cheese.

Research paper thumbnail of The antimicrobial peptide pheromone Plantaricin A increases antioxidant defenses of human keratinocytes and modulates the expression of filaggrin, involucrin, β-defensin 2 and tumor necrosis factor-α genes

Experimental Dermatology, 2012

Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesiz... more Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesized chemically and used as a pure peptide or synthesized biologically using Lactobacillus plantarum DC400 co-cultured with Lactobacillus sanfranciscensis DPPMA174. Cell-free supernatant (CFS) was used as a crude PlnA preparation. As estimated using the 3-(4,5-dimethyl-2-yl)-2,5-diphenyltetrazolium bromide and the 2',7'-dichlorofluorescein diacetate assays, both PlnA preparations increased the antioxidant defenses of human NCTC 2544 keratinocytes. PlnA (10 μg/ml) had a higher activity than hyaluronic acid or 125 μg/ml α-tocopherol. Effects on the transcriptional regulation of filaggrin (FLG), involucrin (IVL), hyaluronan synthase (HAS2), human β-defensin-2 (HBD-2) and tumor necrosis factor-alpha (TNF-α) genes were assayed. Compared with the control, expression of the FLG gene in NCTC 2544 cells increased in cells treated with hyaluronic acid, 1 or 10 μg/ml PlnA. Compared with the control, the level of IVL gene expression increased in NCTC 2544 cells treated with 10 μg/ml PlnA. No significant difference was found between the level of the HAS2 gene expressed by control cells and cells treated with PlnA. Compared with chemically synthesized PlnA, the up-regulation of the HBD-2 gene by CFS was higher. Compared with the control, expression of TNF-α decreased in NCTC 2544 cells after treatment with 1 or 10 μg/ml of chemically synthesized PlnA. In contrast, the level of TNF-α was highest in the presence of 10 μg/ml CFS-PlnA. These findings suggest that the PlnA was positively sensed by human keratinocytes, promoting antioxidant defenses, barrier functions and antimicrobial activity of the skin.

Research paper thumbnail of The sourdough fermentation may enhance the recovery from intestinal inflammation of coeliac patients at the early stage of the gluten-free diet

European Journal of Nutrition, 2012

Purpose This study aimed at investigating the effect of corn, rice and amaranth gluten-free (GF) ... more Purpose This study aimed at investigating the effect of corn, rice and amaranth gluten-free (GF) sourdoughs on the release of nitric oxide (NO) and synthesis of pro-inflammatory cytokines by duodenal mucosa biopsies of eight coeliac disease (CD) patients. Methods Selected lactic acid bacteria were used as starters for the manufacture of corn, rice or amaranth sourdoughs. Chemically acidified doughs, without bacterial starters, and doughs started with baker's yeast alone were also manufactured from the same GF matrices. Pepsintrypsin (PT) digests were produced from all sourdoughs and doughs, and used to assay the rate of recovery of biopsy specimens from eight CD patients at diagnosis. The release of NO and the synthesis of pro-inflammatory cytokines interferon-c (IFN-c) were assayed. Results During fermentation, lactic acid bacteria acidified and grew well (ca. log 9.0 CFU/g) on all GF matrices, showing intense proteolysis. Duodenal biopsy specimens still released NO and IFN-c when subjected to treatments with basal medium (control), PT-digest from chemically acidified doughs and PT-digest from doughs fermented with baker's yeast alone. On the contrary, the treatment of all the biopsy specimens with PT-digests from all GF matrices subjected to sourdough fermentation significantly decreased the release of NO and the synthesis of IFN-c. Conclusions During manufacture of GF baked goods, the use of sourdough fermentation could be considered as an adjuvant to enhance the recovery from intestinal inflammation of coeliac patients at the early stage of the glutenfree diet.

Research paper thumbnail of Diversity of the lactic acid bacteria and yeast microbiota switching from firm to liquid sourdough fermentation

Applied and Environmental Microbiology, 2014

Research paper thumbnail of Effects of the Peptide Pheromone Plantaricin A and Cocultivation with Lactobacillus sanfranciscensis DPPMA174 on the Exoproteome and the Adhesion Capacity of Lactobacillus plantarum DC400

Applied and Environmental Microbiology, 2013

This study aimed at investigating the extracellular and cell wall-associated proteins (exoproteom... more This study aimed at investigating the extracellular and cell wall-associated proteins (exoproteome) of Lactobacillus plantarum DC400 when cultivated on modified chemically defined medium (CDM) supplemented with the chemically synthesized pheromone plantaricin A (PlnA) or cocultured with L. plantarum DPPMA20 or Lactobacillus sanfranciscensis DPPMA174. Compared to monoculture, two-dimensional gel electrophoresis (2-DE) analysis showed that the exoproteome of L. plantarum DC400 was affected by PlnA and cocultivation with strains DPPMA20 and, especially, DPPMA174. The highest similarity of the 2-DE maps was found between DC400 cells cultivated in monoculture and in coculture with strain DPPMA20. Almost all extracellular proteins (22 spots) and cell wall-associated proteins (40 spots) which showed decreased or increased levels of synthesis during growth in CDM supplemented with PlnA and/or in coculture with strain DPPMA20 or DPPMA174 were identified. On the basis of the sequences in the Kyoto Encyclopedia of Genes and Genomes database, changes to the exoproteome concerned proteins involved in quorum sensing (QS), the transport system, stress response, carbohydrate metabolism and glycolysis, oxidation/ reduction processes, the proteolytic system, amino acid metabolism, cell wall and catabolic processes, and cell shape, growth, and division. Cultivation with PlnA and cocultivation with strains DPPMA20 and, especially, DPMMA174 markedly increased the capacity of L. plantarum DC400 to form biofilms, to adhere to human Caco-2 cells, and to prevent the adhesion of potential intestinal pathogens. These phenotypic traits were in part related to oversynthesized moonlighting proteins (e.g., DnaK and GroEL, pyruvate kinase, enolase, and glyceraldehyde-3-phosphate dehydrogenase) in response to QS mechanisms and interaction with L. plantarum DPPMA20 and, especially, L. sanfranciscensis DPPMA174. genomic and proteomic studies to elucidate the molecular mechanisms underlying microbial environmental adaptation . Some of the key elements which are responsible for the adaptation of L. plantarum are ascribed to its high metabolic plasticity and multiple regulatory networks (22). Notwithstanding other regulatory factors, QS-mediated mechanisms, such as the luxS gene (23) and peptide pheromone plantaricin A (PlnA) (24), could play a pivotal role in the regulation of the microbial interactions in food (e.g., sourdoughs) and human (intestine) ecosystems.

Research paper thumbnail of Quorum-Sensing Regulation of Constitutive Plantaricin by Lactobacillus plantarum Strains under a Model System for Vegetables and Fruits

Applied and Environmental Microbiology, 2014

Research paper thumbnail of Lactobacillus rossiae, a vitamin B12 producer, represents a metabolically versatile species within the Genus Lactobacillus

PloS one, 2014

Lactobacillus rossiae is an obligately hetero-fermentative lactic acid bacterium, which can be is... more Lactobacillus rossiae is an obligately hetero-fermentative lactic acid bacterium, which can be isolated from a broad range of environments including sourdoughs, vegetables, fermented meat and flour, as well as the gastrointestinal tract of both humans and animals. In order to unravel distinctive genomic features of this particular species and investigate the phylogenetic positioning within the genus Lactobacillus, comparative genomics and phylogenomic approaches, followed by functional analyses were performed on L. rossiae DSM 15814T, showing how this type strain not only occupies an independent phylogenetic branch, but also possesses genomic features underscoring its biotechnological potential. This strain in fact represents one of a small number of bacteria known to encode a complete de novo biosynthetic pathway of vitamin B12 (in addition to other B vitamins such as folate and riboflavin). In addition, it possesses the capacity to utilize an extensive set of carbon sources, a cha...

Research paper thumbnail of Causal relationship between microbial ecology dynamics and proteolysis during manufacture and ripening of protected designation of origin (PDO) cheese Canestrato Pugliese

Applied and environmental microbiology, 2014

Pyrosequencing of the 16S rRNA gene, community-level physiological profiles determined by the use... more Pyrosequencing of the 16S rRNA gene, community-level physiological profiles determined by the use of Biolog EcoPlates, and proteolysis analyses were used to characterize Canestrato Pugliese Protected Designation of Origin (PDO) cheese. The number of presumptive mesophilic lactococci in raw ewes' milk was higher than that of presumptive mesophilic lactobacilli. The numbers of these microbial groups increased during ripening, showing temporal and numerical differences. Urea-PAGE showed limited primary proteolysis, whereas the analysis of the pH 4.6-soluble fraction of the cheese revealed that secondary proteolysis increased mainly from 45 to 75 days of ripening. This agreed with the concentration of free amino acids. Raw ewes' milk was contaminated by several bacterial phyla: Proteobacteria (68%; mainly Pseudomonas), Firmicutes (30%; mainly Carnobacterium and Lactococcus), Bacteroidetes (0.05%), and Actinobacteria (0.02%). Almost the same microbial composition persisted in the...

Research paper thumbnail of Manufacture of Italian Caciotta-type cheeses with adjuncts and attenuated adjuncts of selected non-starter lactobacilli

Selected Lactobacillus paracasei FC2-5, Lactobacillus casei LC01 and Lactobacillus curvatus 2770 ... more Selected Lactobacillus paracasei FC2-5, Lactobacillus casei LC01 and Lactobacillus curvatus 2770 were used for cheese making as adjunct cultures (AC) or attenuated adjunct cultures (AAC). AAC were obtained by sonication treatment. Italian Caciotta-type cheeses were manufactured on an industrial plant scale, including control cheese (CC) without AC, and ripening was lasted 60 days at 10 °C. AAC did not increase the

Research paper thumbnail of The antimicrobial peptide pheromone Plantaricin A increases antioxidant defenses of human keratinocytes and modulates the expression of filaggrin, involucrin, β-defensin 2 and tumor necrosis factor-α genes

Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesiz... more Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesized chemically and used as a pure peptide or synthesized biologically using Lactobacillus plantarum DC400 co-cultured with Lactobacillus sanfranciscensis DPPMA174. Cell-free supernatant (CFS) was used as a crude PlnA preparation. As estimated using the 3-(4,5-dimethyl-2-yl)-2,5-diphenyltetrazolium bromide and the 2',7'-dichlorofluorescein diacetate assays, both PlnA preparations increased the antioxidant defenses of human NCTC 2544 keratinocytes. PlnA (10 μg/ml) had a higher activity than hyaluronic acid or 125 μg/ml α-tocopherol. Effects on the transcriptional regulation of filaggrin (FLG), involucrin (IVL), hyaluronan synthase (HAS2), human β-defensin-2 (HBD-2) and tumor necrosis factor-alpha (TNF-α) genes were assayed. Compared with the control, expression of the FLG gene in NCTC 2544 cells increased in cells treated with hyaluronic acid, 1 or 10 μg/ml PlnA. Compared with the control, the level of IVL gene expression increased in NCTC 2544 cells treated with 10 μg/ml PlnA. No significant difference was found between the level of the HAS2 gene expressed by control cells and cells treated with PlnA. Compared with chemically synthesized PlnA, the up-regulation of the HBD-2 gene by CFS was higher. Compared with the control, expression of TNF-α decreased in NCTC 2544 cells after treatment with 1 or 10 μg/ml of chemically synthesized PlnA. In contrast, the level of TNF-α was highest in the presence of 10 μg/ml CFS-PlnA. These findings suggest that the PlnA was positively sensed by human keratinocytes, promoting antioxidant defenses, barrier functions and antimicrobial activity of the skin.

Research paper thumbnail of Plantaricin A synthesized by Lactobacillus plantarum induces in vitro proliferation and migration of human keratinocytes and increases the expression of TGF-β1, FGF7, VEGF-A and IL-8 genes

Peptides, 2011

This work showed the effect of pheromone plantaricin A (PlnA) on the proliferation and migration ... more This work showed the effect of pheromone plantaricin A (PlnA) on the proliferation and migration of the human keratinocytes NCTC 2544. PlnA was chemically synthesized and used as pure peptide or biologically synthesized during co-cultivation of Lactobacillus plantarum DC400 and Lactobacillus sanfranciscensis DPPMA174. The cell-free supernatant (CFS) was used as the crude preparation containing PlnA. The inductive effect of PlnA on the proliferation of NCTC 2544 cells was higher than that found for hyaluronic acid, a well known skin protective compound. As shown by scratch assay and image analyses, PlnA enhanced the migration of NCTC 2544 cells. Compared to the basal serum free medium (control), the highest inductive effect was found using 10μg/ml of chemically synthesized PlnA. Similar results (P>0.05) were found for CFS. In agreement, the percentage of the starting scratch area was decreased after treatment (24h) with PlnA. The expression of transforming growth factor-β1 (TGF-β1), keratinocyte growth factor 7 (FGF7), vascular endothelial growth factor (VEGF-A), and interleukin-8 (IL-8) genes was affected by PlnA. Compared to control, TGF-β1 gene was under expressed in the first 4h of treatments and up-regulated after 8-24h. On the contrary, FGF7 gene was strongly up-regulated in the first 4h of treatments. Compared to control, VEGF-A and IL-8 genes were always up-regulated during the 4-24h from scratching. Since capable of promoting the proliferation and migration of the human keratinocytes and of stimulating IL-8 cytokine, the use of PlnA for dermatological purposes should be considered.

Research paper thumbnail of Effect of lactose on gut microbiota and metabolome of infants with cow’s milk allergy

Pediatric Allergy and Immunology, 2012

Research paper thumbnail of Proteomics of the bacterial cross-talk by quorum sensing

Journal of Proteomics, 2011

Words such as language and behavior are frequently used to depict "quorum sensing" (QS) in the li... more Words such as language and behavior are frequently used to depict "quorum sensing" (QS) in the literature. Simplifying the concept, language and cross-talk between bacteria, and between bacteria and animal or plants hosts determine the behavior (e.g., beneficial or pathogenic effects). Genomics and transcriptomics were the principal approaches used to study the multiple mechanisms of QS. Nevertheless, sequencing of genomes paved the way for another approach which consists on comparative and functional proteomics. This review aims at describing how the proteomic dictionary translates: (i) the languages (N-acyl-L-homoserine lactones, AHL; autoinducing peptide, AIP; autoinducer-2, AI-2) used by bacteria to communicate; (ii) signals of QS which induce various phenotypes (e.g., virulence, biofilm maturation); (iii) cross-talk between lactic acid bacteria within various food ecosystems (e.g. sourdough and fermented milk); (iv) probiotic messages at intra-and inter-species and interkingdom levels; and (v) words for quorum quenching (QQ).

Research paper thumbnail of Fermentation and proteome profiles of Lactobacillus plantarum strains during growth under food-like conditions

Journal of Proteomics, 2014

and sharing with colleagues.

Research paper thumbnail of NADP-glutamate dehydrogenase activity in nonstarter lactic acid bacteria: effects of temperature, pH and NaCl on enzyme activity and expression

Journal of Applied Microbiology, 2010

Research paper thumbnail of Proteomic Analysis by Two-Dimensional Gel Electrophoresis and Starch Characterization of Triticum turgidum L. var. durum Cultivars for Pasta Making

Journal of Agricultural and Food Chemistry, 2008

Criteria for durum wheat quality are continuously evolving in response to market pressure and con... more Criteria for durum wheat quality are continuously evolving in response to market pressure and consumer's preference. Specific attributes of durum wheat for different end products require more rapid and objective means to grade and classify wheat parcels based on processing potential. A total of 10 durum wheat cultivars were compared for compositional, protein, and starch characteristics. Mean values for the gross composition differed for total protein, gluten, and starch. Two-dimensional electrophoresis (2DE) analysis showed the proteome diversity among the cultivars. As shown by the principal component analysis (PCA) applied to 2DE data of gliadin and glutenin fractions, cultivars differed mainly from the number of proteins and levels of protein expression. As determined by the rapid viscoanalyzer (RVA), swelling power, starch damage, amylose content, and starch pasting properties of 10 cultivars differed significantly. 2DE fingerprinting and amylose content seemed to distinguish specific cultivars being useful tools for selecting suitable durum wheat cultivars for pasta making.

Research paper thumbnail of Use of sourdough fermentation and mixture of wheat, chickpea, lentil and bean flours for enhancing the nutritional, texture and sensory characteristics of white bread

International Journal of Food Microbiology, 2014

This study aimed at investigating the addition of legume (chickpea, lentil and bean) flours to wh... more This study aimed at investigating the addition of legume (chickpea, lentil and bean) flours to wheat flour bread. Type I sourdough containing legumes or wheat-legume flours were prepared and propagated (back slopped) in laboratory, according to traditional protocols that are routinely used for making typical Italian breads. Based on kinetic of acidification and culture-dependent data, the wheat-legume sourdough was further characterized and selected for bread making. As determined by RAPD-PCR and partial sequencing of 16S rDNA gene analyses, lactic acid bacteria in wheat-legume sourdough included Lactobacillus plantarum, Lactobacillus sanfranciscensis, Leuconostoc mesenteroides, Lactobacillus fermentum, Weissella cibaria, Lactobacillus pentosus, Lactobacillus coryneformis, Lactobacillus rossiae, Lactobacillus brevis, Lactobacillus parabuchneri and Lactobacillus paraplantarum. Two breads containing 15% (w/w) of legume (chickpea, lentil and bean) flours were produced using selected wheat-legume sourdough (WLSB) and traditional wheat sourdough (WSB). Compared to wheat yeasted bread (WYB), the level of total free amino acids (FAA) was higher in WSB and WLSB. Phytase and antioxidant activities were the highest in WLSB. Compared to bread WYB, the addition of legume flours decreased the in vitro protein digestibility (IVPD) (WYB versus WSB). However, the dough fermentation with WSLB favored an increase of IVPD. According to the levels of carbohydrates, dietary fibers and resistant starch, WSB and WLSB showed lower values of hydrolysis index (HI) compared to WYB. As showed by texture and image analyses and sensory evaluation of breads, a good acceptability was found for WSB and, especially, WLSB breads.

Research paper thumbnail of Selection and use of autochthonous multiple strain cultures for the manufacture of high-moisture traditional Mozzarella cheese

International Journal of Food Microbiology, 2008

Lactobacillus plantarum 18A, Lactobacillus helveticus 2B, Lactobacillus delbrueckii subsp. lactis... more Lactobacillus plantarum 18A, Lactobacillus helveticus 2B, Lactobacillus delbrueckii subsp. lactis 20F, Streptococcus thermophilus 22C, Enterococcus faecalis 32C and Enterococcus durans 16E were the most acidifying strains within 146 isolates for natural whey starters. The effect of media and temperature on 2 autochthonous multiple strain cultures (AMSI: 18A, 2B, 20F and 22C, 32C and 16E and AMSII: 18A, 2B, 20F and 22C) was studied. Genomic analysis showed a constant cell numbers for AMSII during 16 days of propagation in whey milk. Mozzarella cheese was made by using AMSII, commercial starter (CS) or citric acid (DA). Compared to other cheeses, the DA had a lower level of protein, ash, Ca, free amino acids and a higher level of moisture. Based on confocal laser scanning microscopy analysis, AMSII cheese showed the lowest microstructural variations during the period of storage compared to other cheeses. All the sensory attributes were scored highest for AMSII cheese. ASMII extend the shelf-life to ca. 12−15 days instead of the 5−7 days of traditional high-moisture Mozzarella cheese.

Research paper thumbnail of The antimicrobial peptide pheromone Plantaricin A increases antioxidant defenses of human keratinocytes and modulates the expression of filaggrin, involucrin, β-defensin 2 and tumor necrosis factor-α genes

Experimental Dermatology, 2012

Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesiz... more Plantaricin A (PlnA) is a peptide with antimicrobial and pheromone activities. PlnA was synthesized chemically and used as a pure peptide or synthesized biologically using Lactobacillus plantarum DC400 co-cultured with Lactobacillus sanfranciscensis DPPMA174. Cell-free supernatant (CFS) was used as a crude PlnA preparation. As estimated using the 3-(4,5-dimethyl-2-yl)-2,5-diphenyltetrazolium bromide and the 2',7'-dichlorofluorescein diacetate assays, both PlnA preparations increased the antioxidant defenses of human NCTC 2544 keratinocytes. PlnA (10 μg/ml) had a higher activity than hyaluronic acid or 125 μg/ml α-tocopherol. Effects on the transcriptional regulation of filaggrin (FLG), involucrin (IVL), hyaluronan synthase (HAS2), human β-defensin-2 (HBD-2) and tumor necrosis factor-alpha (TNF-α) genes were assayed. Compared with the control, expression of the FLG gene in NCTC 2544 cells increased in cells treated with hyaluronic acid, 1 or 10 μg/ml PlnA. Compared with the control, the level of IVL gene expression increased in NCTC 2544 cells treated with 10 μg/ml PlnA. No significant difference was found between the level of the HAS2 gene expressed by control cells and cells treated with PlnA. Compared with chemically synthesized PlnA, the up-regulation of the HBD-2 gene by CFS was higher. Compared with the control, expression of TNF-α decreased in NCTC 2544 cells after treatment with 1 or 10 μg/ml of chemically synthesized PlnA. In contrast, the level of TNF-α was highest in the presence of 10 μg/ml CFS-PlnA. These findings suggest that the PlnA was positively sensed by human keratinocytes, promoting antioxidant defenses, barrier functions and antimicrobial activity of the skin.

Research paper thumbnail of The sourdough fermentation may enhance the recovery from intestinal inflammation of coeliac patients at the early stage of the gluten-free diet

European Journal of Nutrition, 2012

Purpose This study aimed at investigating the effect of corn, rice and amaranth gluten-free (GF) ... more Purpose This study aimed at investigating the effect of corn, rice and amaranth gluten-free (GF) sourdoughs on the release of nitric oxide (NO) and synthesis of pro-inflammatory cytokines by duodenal mucosa biopsies of eight coeliac disease (CD) patients. Methods Selected lactic acid bacteria were used as starters for the manufacture of corn, rice or amaranth sourdoughs. Chemically acidified doughs, without bacterial starters, and doughs started with baker's yeast alone were also manufactured from the same GF matrices. Pepsintrypsin (PT) digests were produced from all sourdoughs and doughs, and used to assay the rate of recovery of biopsy specimens from eight CD patients at diagnosis. The release of NO and the synthesis of pro-inflammatory cytokines interferon-c (IFN-c) were assayed. Results During fermentation, lactic acid bacteria acidified and grew well (ca. log 9.0 CFU/g) on all GF matrices, showing intense proteolysis. Duodenal biopsy specimens still released NO and IFN-c when subjected to treatments with basal medium (control), PT-digest from chemically acidified doughs and PT-digest from doughs fermented with baker's yeast alone. On the contrary, the treatment of all the biopsy specimens with PT-digests from all GF matrices subjected to sourdough fermentation significantly decreased the release of NO and the synthesis of IFN-c. Conclusions During manufacture of GF baked goods, the use of sourdough fermentation could be considered as an adjuvant to enhance the recovery from intestinal inflammation of coeliac patients at the early stage of the glutenfree diet.

Research paper thumbnail of Diversity of the lactic acid bacteria and yeast microbiota switching from firm to liquid sourdough fermentation

Applied and Environmental Microbiology, 2014

Research paper thumbnail of Effects of the Peptide Pheromone Plantaricin A and Cocultivation with Lactobacillus sanfranciscensis DPPMA174 on the Exoproteome and the Adhesion Capacity of Lactobacillus plantarum DC400

Applied and Environmental Microbiology, 2013

This study aimed at investigating the extracellular and cell wall-associated proteins (exoproteom... more This study aimed at investigating the extracellular and cell wall-associated proteins (exoproteome) of Lactobacillus plantarum DC400 when cultivated on modified chemically defined medium (CDM) supplemented with the chemically synthesized pheromone plantaricin A (PlnA) or cocultured with L. plantarum DPPMA20 or Lactobacillus sanfranciscensis DPPMA174. Compared to monoculture, two-dimensional gel electrophoresis (2-DE) analysis showed that the exoproteome of L. plantarum DC400 was affected by PlnA and cocultivation with strains DPPMA20 and, especially, DPPMA174. The highest similarity of the 2-DE maps was found between DC400 cells cultivated in monoculture and in coculture with strain DPPMA20. Almost all extracellular proteins (22 spots) and cell wall-associated proteins (40 spots) which showed decreased or increased levels of synthesis during growth in CDM supplemented with PlnA and/or in coculture with strain DPPMA20 or DPPMA174 were identified. On the basis of the sequences in the Kyoto Encyclopedia of Genes and Genomes database, changes to the exoproteome concerned proteins involved in quorum sensing (QS), the transport system, stress response, carbohydrate metabolism and glycolysis, oxidation/ reduction processes, the proteolytic system, amino acid metabolism, cell wall and catabolic processes, and cell shape, growth, and division. Cultivation with PlnA and cocultivation with strains DPPMA20 and, especially, DPMMA174 markedly increased the capacity of L. plantarum DC400 to form biofilms, to adhere to human Caco-2 cells, and to prevent the adhesion of potential intestinal pathogens. These phenotypic traits were in part related to oversynthesized moonlighting proteins (e.g., DnaK and GroEL, pyruvate kinase, enolase, and glyceraldehyde-3-phosphate dehydrogenase) in response to QS mechanisms and interaction with L. plantarum DPPMA20 and, especially, L. sanfranciscensis DPPMA174. genomic and proteomic studies to elucidate the molecular mechanisms underlying microbial environmental adaptation . Some of the key elements which are responsible for the adaptation of L. plantarum are ascribed to its high metabolic plasticity and multiple regulatory networks (22). Notwithstanding other regulatory factors, QS-mediated mechanisms, such as the luxS gene (23) and peptide pheromone plantaricin A (PlnA) (24), could play a pivotal role in the regulation of the microbial interactions in food (e.g., sourdoughs) and human (intestine) ecosystems.

Research paper thumbnail of Quorum-Sensing Regulation of Constitutive Plantaricin by Lactobacillus plantarum Strains under a Model System for Vegetables and Fruits

Applied and Environmental Microbiology, 2014

Research paper thumbnail of Lactobacillus rossiae, a vitamin B12 producer, represents a metabolically versatile species within the Genus Lactobacillus

PloS one, 2014

Lactobacillus rossiae is an obligately hetero-fermentative lactic acid bacterium, which can be is... more Lactobacillus rossiae is an obligately hetero-fermentative lactic acid bacterium, which can be isolated from a broad range of environments including sourdoughs, vegetables, fermented meat and flour, as well as the gastrointestinal tract of both humans and animals. In order to unravel distinctive genomic features of this particular species and investigate the phylogenetic positioning within the genus Lactobacillus, comparative genomics and phylogenomic approaches, followed by functional analyses were performed on L. rossiae DSM 15814T, showing how this type strain not only occupies an independent phylogenetic branch, but also possesses genomic features underscoring its biotechnological potential. This strain in fact represents one of a small number of bacteria known to encode a complete de novo biosynthetic pathway of vitamin B12 (in addition to other B vitamins such as folate and riboflavin). In addition, it possesses the capacity to utilize an extensive set of carbon sources, a cha...