scholarly journals Probiotic Potential and Technological Properties of Bacteriocinogenic Lactococcus lactis Subsp. Lactis UTNGt28 from a Native Amazonian Fruit as a Yogurt Starter Culture

2020 ◽  
Vol 8 (5) ◽  
pp. 733 ◽  
Author(s):  
Gabriela N. Tenea ◽  
Jimena Suárez
Keyword(s):  
Cell Viability ◽  
Lactococcus Lactis ◽  
Starter Culture ◽  
Principal Component ◽  
Titratable Acidity ◽  
Technological Properties ◽  
Positive Direction ◽  
Lactococcus Lactis Subsp ◽  
Whole Milk ◽  
Significant Difference

A native Lactococcus lactis subsp. lactis UTNGt28 (GenBank accession no: MG675576.1) isolated from Amazonian fruit of the tropical Caimitillo (Chrysophyllum oliviforme) tree and the commercial strain Lactococcus lactis subsp lactis ATCC11454 (LacAT) were targeted ex vitro in whole milk in combination with Streptococcus thermophilus ATCC19258 to obtain a fermented probiotic beverage. Concomitant with cell viability determination during storage (28 days), the pH, titratable acidity, syneresis, protein and fat were evaluated. The results indicated that neither UTNGt28 nor LacAT displayed a high capacity to ferment whole milk and survive during storage; a statistically significant difference (p < 0.05) in cell viability was registered for UTNGt28 compared with LacAT when inoculated alone or in combination with S. thermophilus. A principal component analysis showed a clear difference between the yogurt formulations at day 1 and 28 of storage. The PC 1 explained 46.8% of the total variance (day 28), was loaded in the negative (−) direction with titratable acidity (% lactic acid), while the PC 2 explained 22.5% (day 1) with pH. PC 1 was loaded in the positive (+) direction with pH, cell viability, syneresis, fat and protein. Overall results indicated that UTNGt28 has the technological properties for further development of a new probiotic product.

Growth, nisA Gene Expression, and In Situ Activity of Novel Lactococcus lactis subsp. cremoris Costarter Culture in Commercial Hard Cheese Production

2017 ◽  
Vol 80 (12) ◽  
pp. 2137-2146 ◽  
Author(s):  
Dimitrios Noutsopoulos ◽  
Athanasia Kakouri ◽  
Eleftheria Kartezini ◽  
Dimitrios Pappas ◽  
Efstathios Hatziloukas ◽  
...  
Keyword(s):  
Gene Expression ◽  
Lactococcus Lactis ◽  
Starter Culture ◽  
Fold Increase ◽  
Raw Milk ◽  
Good Growth ◽  
Lactococcus Lactis Subsp ◽  
Quantitative Expression ◽  
Hard Cheese

ABSTRACT This study evaluated in situ expression of the nisA gene by an indigenous, nisin A–producing (NisA+) Lactococcus lactis subsp. cremoris raw milk genotype, represented by strain M78, in traditional Greek Graviera cheeses under real factory-scale manufacturing and ripening conditions. Cheeses were produced with added a mixed thermophilic and mesophilic commercial starter culture (CSC) or with the CSC plus strain M78 (CSC+M78). Cheeses were sampled after curd cooking (day 0), fermentation of the unsalted molds for 24 h (day 1), brining (day 7), and ripening of the brined molds (14 to 15 kg each) for 30 days in a fully controlled industrial room (16.5°C; 91% relative humidity; day 37). Total RNA was directly extracted from the cheese samples, and the expression of nisA gene was evaluated by real-time reverse transcription PCR (qRT-PCR). Agar overlay and well diffusion bioassays were correspondingly used for in situ detection of the M78 NisA+ colonies in the cheese agar plates and antilisterial activity in whole-cheese slurry samples, respectively. Agar overlay assays showed good growth (&gt;8 log CFU/g of cheese) of the NisA+ strain M78 in coculture with the CSC and vice versa. The nisA expression was detected in CSC+M78 cheese samples only, with its expression levels being the highest (16-fold increase compared with those of the control gene) on day 1, followed by significant reduction on day 7 and almost negligible expression on day 37. Based on the results, certain intrinsic and mainly implicit hurdle factors appeared to reduce growth prevalence rates and decrease nisA gene expression, as well as the nisin A–mediated antilisterial activities of the NisA+ strain M78 postfermentation. To our knowledge, this is the first report on quantitative expression of the nisA gene in a Greek cooked hard cheese during commercial manufacturing and ripening conditions by using a novel, rarely isolated, indigenous NisA+ L. lactis subsp. cremoris genotype as costarter culture.

scholarly journals Comparison of apples from organic and integrated farming

2010 ◽  
Vol 16 (3) ◽  
Author(s):  
M. Tóth-Markus ◽  
N. Adányi ◽  
F. Boross ◽  
H. G. Daood ◽  
D. Bánáti ◽  
...  
Keyword(s):  
Radical Scavenging ◽  
Principal Component ◽  
Zinc Content ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Total Polyphenols ◽  
Integrated Farming ◽  
Copper And Zinc ◽  
Significant Difference ◽  
Trolox Equivalent

Prima’, ‘Gala’, ‘Remo’, ‘Topáz’, ‘Idared’, ‘Releika’, ‘Resi’, ‘Rubinola’, ‘Rajka’, ‘Rewena’ and ‘Florina’ apple cultivars, both from organic and integrated farming, from Pallag and Újfehértó, were compared. Average size, weight, soluble solids, titratable acidity, total polyphenols, free radical scavenging capacity expressed as Trolox equivalent (TEAC), copper and zinc were determined at harvest and after cool storage. Organic apples were more acidic, while integrated fruits had mostly higher copper and zinc content. Total polyphenols and TEAC values did not show a significant difference as a function of farming technology. A principal component analysis shows the separation of provenances as well as stored and fresh apples. Results are considered as preliminary.

scholarly journals Technological properties of Lactococcus lactis subsp. lactis bv. diacetylactis obtained from dairy and non-dairy niches

2019 ◽  
Vol 51 (1) ◽  
pp. 313-321 ◽  
Author(s):  
Andressa Fusieger ◽  
Mayra Carla Freitas Martins ◽  
Rosângela de Freitas ◽  
Luís Augusto Nero ◽  
Antônio Fernandes de Carvalho
Keyword(s):  
Lactococcus Lactis ◽  
Technological Properties ◽  
Lactococcus Lactis Subsp

Development of human lactic acid (LAB) gastrointestinal microbiota in a Greek rural population

2008 ◽  
Vol 3 (1) ◽  
pp. 55-60 ◽  
Author(s):  
Dimitrios Vassos ◽  
Vassiliki Maipa ◽  
Chrysa Voidarou ◽  
Athanasios Alexopoulos ◽  
Eugenia Bezirtzoglou
Keyword(s):  
Lactic Acid ◽  
Lactococcus Lactis ◽  
Age Groups ◽  
Morphological Characteristics ◽  
Lactobacillus Brevis ◽  
Growth Patterns ◽  
Gastrointestinal Microbiota ◽  
Daily Consumption ◽  
Lactococcus Lactis Subsp ◽  
Significant Difference

AbstractIn order to investigate the Lactic Acid Bacteria (LAB) of the gut, fecal samples were collected and analyzed from 120 healthy Greek volunteers ranging from age 1 to age 85, all of whom declared daily consumption of local fermented dairy products. LAB strains were isolated using selective media under aerobic or anaerobic conditions. Identification of the isolates was based on their growth patterns, morphological characteristics, and carbohydrate fermentation profiles. There was no significant difference in the abundance of Lactobacillus brevis, Lactococcus lactis subsp. cremoris, Lactococcus lactis, Lactobacilus paracasei and Bifidobacterium sp., in all samples. Lactobacillus fermentum, Lactobacillus plantarum, Lactococcus casei, Lactococcus pentosus, Lactococcus lactis subsp. lactis, Lactococcus delbrueckii subsp. lactis, Enterococcus casseliflavus, Enterococcus faecalis, Enterococcus faecium, Enterococcus avium and Leuconostoc sp. were also recovered, mainly from the adults and elders rather than the children’s group. Despite the above differences in LAB species observed mostly between the younger and the other two age groups, differences were also observed within all groups, indicating that healthy subjects of all ages are colonized by a diverse lactoflora in terms of total or dominant species.

Use of a Nisin-Producing Starter Culture of Lactococcus lactis subsp. lactis To Improve Traditional Fish Fermentation in Senegal

2009 ◽  
Vol 72 (9) ◽  
pp. 1930-1934 ◽  
Author(s):  
MICHEL BAKAR DIOP ◽  
ROBIN DUBOIS-DAUPHIN ◽  
JACQUELINE DESTAIN ◽  
EMMANUEL TINE ◽  
PHILIPPE THONART
Keyword(s):  
Lactococcus Lactis ◽  
Pathogenic Bacteria ◽  
Starter Culture ◽  
Enteric Bacteria ◽  
Local Market ◽  
Spontaneous Fermentation ◽  
Ambient Temperatures ◽  
Lactococcus Lactis Subsp ◽  
Lean Fish ◽  
Fermentation Strategy

Lactococcus lactis subsp. lactis strain CWBI B1410, which produces various antibacterial compounds including organic acids and nisin, was used as a starter culture to improve the traditional Senegalese fish fermentation in which fish are mostly transformed to guedj by spontaneous fermentation for 24 to 48 h at ambient temperatures near 30°C followed by salting (with NaCl) and sun drying. Assays were performed on lean fish (Podamasys jubelini) and fat fish (Arius heudelotii) purchased at a local market. The total viable microbial counts in raw fillets of P. jubelini and A. heudelotii were 5.78 and 5.39 log CFU/g, respectively. Populations of enteric bacteria (which can include pathogenic bacteria) in P. jubelini and A. heudelotii were 4.08 and 4.12 log CFU/g, respectively. Spontaneous fermentation of raw fillets at 30°C led to the proliferation of enteric bacteria to 9 log CFU/g after 24 h in fermented P. jubelini and A. heudelotii fillets with pH values of 6.83 and 7.50, respectively. When raw fish fillets were supplemented with glucose (1%, wt/wt) and inoculated with Lactococcus lactis (107 CFU/g), the pH decreased to about 4.60 after 10 h at 30°C, and nisin activity was detected in juice from the fillets. Traditionally fermented fillets of P. jubelini and A. heudelotii contained enteric bacteria at higher levels of 4 and 2 log CFU/g, respectively, than did fillets of the same fish supplemented with glucose and fermented with the starter culture. These data suggest that this new fish fermentation strategy combined with salting and drying can be used to enhance the safety of guedj.

Behavior of Staphylococcus aureus in Culture Broth, in Raw and Thermized Milk, and during Processing and Storage of Traditional Greek Graviera Cheese in the Presence or Absence of Lactococcus lactis subsp. cremoris M104, a Wild, Novel Nisin A–Producing Raw Milk Isolate

2014 ◽  
Vol 77 (10) ◽  
pp. 1703-1714 ◽  
Author(s):  
JOHN SAMELIS ◽  
ALEXANDRA LIANOU ◽  
ELENI C. PAPPA ◽  
BOJANA BOGOVIČ-MATIJAŠIĆ ◽  
MARIA PARAPOULI ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Lactococcus Lactis ◽  
Starter Culture ◽  
Raw Milk ◽  
Culture Broth ◽  
Microbial Consortia ◽  
Aureus Strain ◽  
Lactococcus Lactis Subsp ◽  
Log Reduction ◽  
And Storage

This study was conducted to evaluate the behavior of Staphylococcus aureus during processing, ripening, and storage of traditional Greek Graviera cheese in accordance with European Union Regulation 1441/2007 for coagulase-positive staphylococci in thermized milk cheeses. Lactococcus lactis subsp. cremoris M104, a wild, novel nisin A–producing (NisA+) strain, also was evaluated as an antistaphylococcal adjunct. A three-strain cocktail of enterotoxigenic (Ent+) S. aureus increased by approximately 2 log CFU/ml when coinoculated (at approximately 3 log CFU/ml) in thermized Graviera cheese milk (TGCM; 63°C for 30 s) with commercial starter culture (CSC) and/or strain M104 at approximately 6 log CFU/ml and then incubated at 37°C for 3 h. However, after 6 h at 37°C, significant retarding effects on S. aureus growth were noted in the order TGCM+M104 &gt; TGCM+CSC = TGCM+CSC+M104 &gt; TGCM. Additional incubation of TGCM cultures at 18°C for 66 h resulted in a 1.2-log reduction (P &lt; 0.05) of S. aureus populations in TGCM+M104. The Ent+ S. aureus cocktail did not grow but survived during ripening and storage when inoculated (at approximately 3 log CFU/g) postcooking into Graviera mini cheeses prepared from TGCM+CSC or TGCM+CSC+M104, ripened at 18°C and 90% relative humidity for 20 days, and stored at 4°C in vacuum packages for 2 months. A rapid 10-fold decrease (P &lt; 0.05) in S. aureus populations occurred within the first 24 h of cheese fermentation. Reductions of S. aureus were greater by approximately 0.4 log CFU/g in CSC+M104 than in CSC only cheeses, concomitantly with the presence of NisA+ M104 colonies and nisin-encoding genes in the CSC plus M104 cheeses and their corresponding microbial consortia only. A high level of selective survival of a naturally nisin-resistant EntC+ S. aureus strain from the cocktail was noted in CSC+M104 cheeses and in coculture with the NisA+ M104 strain in M-17 broth. In conclusion, although S. aureus growth inhibition is assured during Graviera cheese ripening, early growth of the pathogen during milk curdling and curd cooking operations may occur. Nisin-resistant S. aureus strains that may contaminate Graviera cheese milks postthermally may be difficult to control even by the application of the NisA+ L. lactis subsp. cremoris strain M104 as a bioprotective adjunct culture.

Sign in / Sign up

Export Citation Format

Share Document