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Cookies Fortified with Clitoria ternatea Butterfly Pea Flower Petals: Antioxidant Capacity, Nutritional Composition, and Sensory Profile
This study aimed to fortify cookies to be functional food by adding Clitoria ternatea flower (CT) at concentrations ranging from 0 to 8%. Sensory profiling identified 6% CT as optimal for organoleptic attributes. The addition of CT did not significantly impact protein, lipid, and ash content but decreased energy value and increased insoluble and soluble fibre levels. The inclusion of 6% CT had a significant effect on the overall total phenolic content (TPC), which increased compared to the control sample. Antioxidative activity analyses showed enhanced antioxidative activity in ABTS, DPPH, ORACFL, and PCL assays. The addition of 6% CT inhibited hydroperoxide production in cookies. However, over a period of 6 weeks, a significant rise in peroxide value was observed during the 4th and 6th weeks of storing fortified cookies. All assessed products met the high microbiological quality standards. The sensory evaluation scores showed that CT can create cookies with health benefits and a good overall acceptance score. The texture of the cookies gradually became softer, but no significant changes in visual appearance were observed. CT can be extensively used in baked cookies as a rich source of polyphenols with strong antioxidant properties and high fibre content, as well as a fortification source for the development of functional foods.
Molekularna charakterystyka sposobu hamowania procesu quorum sensing przez wybrane olejki eteryczne u Pseudomonas spp. wyizolowanych z żywności
Potassium Chloride, Sodium Lactate and Sodium Citrate Impaired the Antimicrobial Resistance and Virulence of Pseudomonas aeruginosa NT06 Isolated from Fish
Sodium chloride (NaCl) is a commonly used additive in minimally processed fish-based products. The addition of NaCl to fish products and packaging in a modified atmosphere is usually efficient with regard to limiting the occurrence of the aquatic environmental pathogen Pseudomonas aeruginosa. Given the negative effects of excess NaCl in the diet, there is a growing demand to reduce NaCl in food products with safer substituents, but the knowledge of their impact on antibiotic resistant P. aeruginosa is limited. This study aimed to evaluate the physiological and transcriptome characteristics of P. aeruginosa NT06 isolated from fish and to determine the effect of selected concentrations of alternative NaCl compounds (KCl/NaL/NaC) on the P. aeruginosa NT06 virulence phenotype and genotype. In the study, among the isolated microorganisms, P. aeruginosa NT06 showed the highest antibiotic resistance (to ampicillin, ceftriaxone, nalidixic acid, and norfloxacin) and the ability to grow at 4 °C. The Comprehensive Antibiotic Resistance Database (CARD) and the Virulence Factor Database (VFDB) revealed the presence of 24 and 134 gene products assigned to AMR and VF in the P. aeruginosa NT06 transcriptome, respectively. KCl, KCl/NaL and KCl/NaL/NaC inhibited pyocyanin biosynthesis, elastase activity, and protease activity from 40 to 77%. The above virulence phenotypic observations were confirmed via RT–qPCR analyses, which showed that all tested AMR and VF genes were the most downregulated due to KCl/NaL/NaC treatment. In conclusion, this study provides insight into the potential AMR and VF among foodborne P. aeruginosa and the possible impairment of those features by KCl, NaL, and NaC, which exert synergistic effects and can be used in minimally processed fish-based products.
Fermenting of flaxseed cake with Lactiplantibacillus plantarum K06 to increase its application as food ingredient - The effect on changes in protein and phenolic profiles, cyanogenic glycoside degradation, and functional properties
High-Resolution Melting Analysis Potential for Saccharomyces cerevisiae var. boulardii Authentication in Probiotic-Enriched Food Matrices
To date, the only probiotic yeast with evidence of health-promoting effects is Saccharomyces cerevisiae var. boulardii. The expanded market including dietary supplements and functional foods supplemented with Saccharomyces cerevisiae var. boulardii creates an environment conductive to food adulterations, necessitating rapid testing to verify product probiotic status. Herein, qPCR-HRM analysis was tested for probiotic yeast identification. The effectiveness of the primer pairs’ set was examined, designed to amplify heterogeneous regions in (a) rDNA sequences previously designed to identify food-derived yeast and (b) genes associated with physiological and genotypic divergence of Saccharomyces cerevisiae var. boulardii. Preliminary tests of amplicons’ differentiation power enabled the selection of interspecies sequences for 18SrRNA and ITS and genus-specific sequences HO, RPB2, HXT9 and MAL11. The multi-fragment qPCR-HRM analysis was sufficient for culture-dependent Saccharomyces cerevisiae var. boulardii identification and proved effective in the authentication of dietary supplements’ probiotic composition. The identification of S. cerevisiae var. boulardii in complex microbial mixtures of kefir succeeded with more specific intragenus sequences HO and RPB2. The predominance of S. cerevisiae var. boulardii in the tested matrices, quantitatively corresponded to the probiotic-enriched food, was crucial for identification with qPCR–HRM analysis. Considering the reported assumptions, qPCR-HRM analysis is an appropriate tool for verifying probiotic-enriched food.
Global transcriptome analysis of Pseudomonas aeruginosa NT06 response to potassium chloride, sodium lactate, sodium citrate, and microaerophilic conditions in a fish ecosystem
Abstract Pseudomonas aeruginosa is an opportunistic pathogen that recently has been increasingly isolated from foods, especially from minimally processed fish-based products. Those are preserved by the addition of sodium chloride (NaCl) and packaging in a modified atmosphere. However, the current trends of minimizing NaCl content may result in an increased occurrence of P. aeruginosa. NaCl can be replaced with potassium chloride (KCl) or sodium salts of organic acids. Herein, we examined the antimicrobial effects of KCl, sodium lactate (NaL), sodium citrate (NaC), and sodium acetate (NaA) against P. aeruginosa NT06 isolated from fish. Transcriptome response of cells grown in medium imitating a fish product supplemented with KCl and KCl/NaL/NaC and maintained under microaerophilic conditions was analysed. Flow cytometry analysis showed that treatment with KCl and KCl/NaL/NaC resulted in changed metabolic activity of cells. In response to KCl and KCl/NaL/NaC treatment, genes related to cell maintenance, stress response, quorum sensing, virulence, efflux pump, and metabolism were differentially expressed. Collectively, our results provide an improved understanding of the response of P. aeruginosa to NaCl alternative compounds that can be implemented in fish-based products and encourage further exploration of the development of effective methods to protect foods against the P. aeruginosa, underestimate foodborne bacteria.
Gallic and ferulic acids suppress proteolytic activities and volatile trimethylamine production in the food‐borne spoiler Rahnella aquatilis KM05
AbstractBACKGROUNDRahnella aquatilis is a recognised microbial threat that alters the sensory properties of seafood. The high frequency with which R. aquatilis is isolated from fish has prompted a search for alternative preservatives. In the present study, in vitro and fish‐based ecosystem (raw salmon‐based medium) approaches were used to validate the antimicrobial effects of gallic (GA) and ferulic (FA) acids against R. aquatilis KM05. The results were compared with data describing the response of KM05 to sodium benzoate. Bioinformatics data of the whole genome were used to analyse the potential for fish spoilage by KM05 in detail, and the results revealed the main physiological characteristics that underlie reduced seafood quality.RESULTSIn the KM05 genome, the most abundantly enriched Gene Ontology terms were ‘metabolic process’, ‘organic substance metabolic process’ and ‘cellular process’. Through an evaluation of the Pfam annotations, 15 annotations were found to be directly involved in the proteolytic activity of KM05. Peptidase_M20 was the most abundantly represented (abundance value of 14060). Proteins representing the CutC family (abundance value of 427) indicated the potential for KM05 degradation of trimethyl‐amine‐N‐oxide. Subinhibitory concentrations of GA and FA suppressed the proteolytic activities of KM05 both in vitro and in RS medium by an average of 33–45%. These results were confirmed by quantitative real‐time PCR experiments, which also showed that the expression levels of genes involved in proteolytic activities and volatile trimethylamine production were also decreased.CONCLUSIONPhenolic compounds can be used as potential food additives for preventing quality deterioration of fish products. © 2023 Society of Chemical Industry.
Acetic and citric acids effect the type II secretion system and decrease the metabolic activities of salmon spoilage-related Rahnella aquatilis KM05
AbstractRahnella aquatilis causes seafoods to spoil by metabolizing sulfur-containing amino acids and/or proteins, producing H2S in products. The type II secretion system (T2SS) regulates the transport of proteases from the cytoplasm to the surrounding environment and promotes bacterial growth at low temperatures. To prevent premature fish spoilage, new solutions for inhibiting the T2SS of bacteria should be researched. In this study, global transcriptome sequencing was used to analyze the spoilage properties of R. aquatilis KM05. Two of the mapped genes/coding sequences (CDSs) were matched to the T2SS, namely, qspF and gspE, and four of the genes/CDSs, namely, ftsH, rseP, ptrA and pepN, were matched to metalloproteases or peptidases in R. aquatilis KM05. Subinhibitory concentrations of citric (18 µM) and acetic (41 µM) acids caused downregulation of T2SS-related genes (range from − 1.0 to -4.5) and genes involved in the proteolytic activities of bacteria (range from − 0.5 to -4.0). The proteolytic activities of R. aquatilis KM05 in vitro were reduced by an average of 40%. The in situ experiments showed the antimicrobial properties of citric and acetic acids against R. aquatilis KM05; the addition of an acidulant to salmon fillets limited microbial growth. Citric and acetic acids extend the shelf life of fish-based products and prevent food waste.
Effect of Flax Cake and Lupine Flour Addition on the Physicochemical, Sensory Properties, and Composition of Wheat Bread
Bread is consumed by people all over the world. Its quality may be modified by the application of other raw materials or changes in production technology. The addition of flax cake (FC) and lupine flour (LF) was proposed as a modification of the nutritional value of wheat bread. Bread with non-fermented and fermented FC and LF was prepared, and its physicochemical, sensory properties and composition were compared to wheat bread. A higher than 5% addition of these components reduced the bread volume and increased their hardness, gumminess, and chewiness. To reduce the negative impact of these additives on the physical and sensory properties of bread, these raw materials were fermented by selected starter cultures. The addition of FC and LF fermented by Lactobacillus plantarum lowered the undesirable changes in the physicochemical properties of the bread. It also slightly increased the overall acceptability of the products. Propionic fermentation lowered sensory assessment rates considerably. The following changes in the composition of bread prepared with the addition of fermented by L. plantarum FC and LF were noted: increase in protein (by ~30%), ash (by ~100%), both soluble and insoluble fiber (by ~500%) content. The starch content was reduced by about 18–20%. The modifications increased the nutritional value of the obtained bread, preserving its physicochemical properties and sensory acceptability.