Fermented, ultrasonicated, and dehydrated bovine colostrum: Changes in antimicrobial properties and immunoglobulin content.

This study evaluated the influence of fermentation with Lactobacillus plantarum LUHS135 and Lactobacillus paracasei LUHS244, ultrasonication, and different methods of dehydration on the content of IgG, IgA, and IgM in bovine colostrum (BC), as well as the antimicrobial activity of the treated and fresh BC samples [fresh = BC; freeze dried = BClyoph; vacuum dried (+45°C) = BCvacdried; BC fermented with LUHS135 = BCLUHS135; BC fermented with LUHS244 = BCLUHS244; BC fermented with LUHS135 and freeze dried = BCLUHS135lyoph; BC fermented with LUHS244 and freeze dried = BCLUHS244 lyoph; BC fermented with LUHS135 and vacuum dried = BCLUHS135 vacdried; BC fermented with LUHS244 and vacuum dried = BCLUHS244 vacdried; BC ultrasonicated and freeze dried = BCultr lyoph; BC ultrasonicated and vacuum dried = BCultr vacdried]. The antimicrobial activity was assessed against Klebsiella pneumoniae, Salmonella enterica, Pseudomonas aeruginosa, Acinetobacter baumanni, Proteus mirabilis, methicillin-resistant Staphylococcus aureus, Enterococcus faecalis, Enterococcus faecium, Bacillus cereus, Streptococcus mutans, Enterobacter cloacae, Citrobacter freundii, Staphylococcus epidermis, Staphylococcus haemolyticus, and Pasteurella multocida using the agar well diffusion method, as well as in liquid medium. In liquid medium analysis showed that the fermented BC samples had the broadest antimicrobial spectrum (of 15 tested pathogenic strains, BCLUHS135 vacdried and BCLUHS135lyoph inhibited 13; BCLUHS244 vacdried inhibited 12; and BCLUHS135, BCLUHS244, and BCLUHS244 lyoph inhibited 11). Based on the inhibition zones, BCLUHS135lyoph samples exhibited the broadest inhibition spectrum, inhibiting the growth of 12 of the 15 tested pathogenic strains). According to the lactic acid bacteria strain selected for BC fermentation, different properties of the BC will be obtained. To ensure a broad antimicrobial spectrum and high IgG content, fermentation with LUHS135 can be recommended (IgG concentration in BCLUHS135 was retained), whereas fermentation with LUHS244 will provide a high IgM concentration (IgM concentration increased by 48.8 and 21.6% in BCLUHS244 and BCLUHS244lyoph samples, respectively). However, IgA is very sensitive for fermentation, and further studies are needed to increase IgA stability in BC. Finally, fermented BC can be recommended as a food/beverage ingredient, providing safety, as well as improved functionality through displaying a broad spectrum of antimicrobial activities.

Improvement of the antimicrobial activity of lactic acid bacteria in combination with berries/fruits and dairy industry by-products.

BACKGROUND: By-products from berries/fruits (B/F) and the dairy industry (DI) are an important environmental issue in many countries. In the present study, the concept of an improvement of the antimicrobial activity of lactic acid bacteria (LAB) in combination with B/F (raspberries, blackcurrants, apples, rowanberries) and DI by-products was analysed. Antimicrobial activities of the B/F by-products and LAB (13 LAB strains were estimated against 15 pathogenic strains) were evaluated, with whey substrate being used for the selected and the highest antimicrobial activities showing LAB cultivation. RESULTS: The broadest spectrum of pathogenic bacteria inhibition was shown by lyophilised blackcurrant and apple by-products, which inhibited 13 and 12 pathogenic strains of the 15 strains analysed, respectively. The strongest inhibition of the tested pathogens were shown by the Lactobacillus uvarum LUHS245 and Lactobacillus casei LUHS210 and, for the abovementioned LAB biomass preparation, whey enriched with 2.5 g 100 g-1 glucose, 2.0 g 100 g-1 yeast extract and 0.5 g 100 g-1 saccharose is a suitable and sustainable substrate. The B/F by-product's antimicrobial activity can be enhanced in combination with the LUHS245 and LUHS210 strains. CONCLUSION: LAB, B/F and DI by-products can be used for preparation of antimicrobial products because the combination of compounds from different origins showed higher antimicrobial properties. © 2019 Society of Chemical Industry.

Plant-based proteinaceous snacks: Effect of fermentation and ultrasonication on end-product characteristics.

The study aimed at the development of a sufficient technology to improve sensory, textural, physical, and microbiological properties of peas snacks (Ps) using solid-state fermentation (SSF) and submerged fermentation (SMF) with two different lactic acid bacteria (LAB) strains (Lactobacillus casei LUHS210 and Lactobacillus uvarum LUHS245) for 24 hr and ultrasonication (10, 20, and 30 min). To ensure safety of the used technologies, microbiological characteristics and biogenic amines (BAs) content in treated Ps were analyzed. Additionally, a different salt content (3.6 and 1.0 g/100 g) was used for snacks preparation. The obtained results revealed that used treatments reduced enterobacteria in Ps, while in fermented Ps, yeast/moulds were not found. Ps with the lower salt content were more acidic and harder (0.90 mJ), and there was a significant effect (p < .05) due to the fermentation method, LAB strains, and ultrasonication on the texture of final product. Different salt content significantly affected the color coordinates of the Ps tested (p < .05). The predominant biogenic amines in Ps were phenylethylamine and spermidine. However, the reduction of some BAs after samples fermentation was observed. To conclude, acceptable formulations of Ps can be obtained with 1.0 g/100 g salt, and by using fermentation, as the end-product is more attractive to consumers than those prepared with 3.6 g/100 g salt and using ultrasonication.

Comparison studies of the chemical, physical, technological, and microbiological characteristics of the European roe deer, boar, red deer, and beaver hunted wild game meat.

The aim of this research was to perform comparison studies of the chemical, physical, technological, and microbiological characteristics, including biogenic amines (BAs) and volatile compounds (VC), of the European roe deer (RDM), boar (BoM), red deer (ReDM), and beaver (BM) hunted wild game meat (HWGM). The outcome of this study showed a significant effect (p < .05) of animal species on protein content, pH, drip loss, shear force, cooking loss, color coordinates, total count of enterobacteria, and most of the VC. ReDM had the highest protein content (23.15%), cooking loss, L* and b* values. The lowest protein and cholesterol content and L* value and the highest pH, shear force, drip loss, and fat content were established in BM having the highest content of unsaturated fatty acids (UFA) (64.12% from total FA). The total UFA content in ReDM and BM was almost twofold higher, compared with saturated FA. Small amounts of main BAs (<7.8 mg/kg) were found in ReDM and BM, while a higher content of putrescine in RDM and BoM was established. The main VCs in HWGM were acetoin, pelargonic, and acetic acid. These findings provide a valuable data about the HWGM quality characteristics and might aid food manufacturers to improve and enhance the processing of the HWGM.

The Essential Oil and Hydrolats from Myristica fragrans Seeds with Magnesium Aluminometasilicate as Excipient: Antioxidant, Antibacterial, and Anti-inflammatory Activity.

Nutmeg (Myristica fragrans) essential oil has antimicrobial, antiseptic, antiparasitic, anti-inflammatory, and antioxidant properties. We have recently demonstrated that hydrodistillation of nutmeg essential oil by applying magnesium aluminometasilicate as an excipient significantly increases both the content and amount of bioactive substances in the oil and hydrolats. In this study, we aimed to compare the antioxidant, antimicrobial, and anti-inflammatory activity of hydrolats and essential oil obtained by hydrodistillation in the presence and absence of magnesium aluminometasilicate as an excipient. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging method revealed that magnesium aluminometasilicate did not significantly improved antioxidant activity of both essential oil and hydrolat. Antibacterial efficiency was evaluated by monitoring growth of 15 bacterial strains treated by a range of dilutions of the essential oil and the hydrolats. Essential oil with an excipient completely inhibited the growth of E. faecalis, S. mutans (referent), and P. multocida, whereas the pure oil was only efficient against the latter strain. Finally, the anti-inflammatory properties of the substances were assessed in a fibroblast cell culture treated with viral dsRNR mimetic Poly I:C. The essential oil with an excipient protected cells against Poly I:C-induced necrosis more efficiently compared to pure essential oil. Also, both the oil and the hydrolats with aluminometasilicate were more efficient in preventing IL-6 release in the presence of Poly I:C. Our results show that the use of magnesium aluminometasilicate as an excipient might change and in some cases improve the biological activities of nutmeg essential oil and hydrolats.

Challenges Associated with Byproducts Valorization-Comparison Study of Safety Parameters of Ultrasonicated and Fermented Plant-Based Byproducts.

In order to promote the efficient use of byproducts from the production of plant-based beverages, which still contain a large amount of nutritional and functional compounds, microbiological and chemical safety characteristics should be evaluated and, if needed, improved. Many challenges are associated with byproducts valorization, and the most important ones, which should be taken into account at the further steps of valorization, are biological and chemical safety. For safety improving, several technological treatments (biological, physical etc.) can be used. In this study, the influence of low-frequency ultrasonication (US) and fermentation with Lactobacillus casei LUHS210 strain, as physical and biotechnological treatments, on the safety characteristics of the byproducts (BYs) from the processing of rice, soy, almond, coconut, and oat drinks was compared. Ultrasonication, as well as fermentation, effectively improved the microbiological safety of BYs. Ultrasonication and fermentation reduced the concentration of deoxynivalenol, on average, by 24% only in soy BYs. After fermentation, 15-acetyldeoxynivalenol was formed in all samples (<12 µg kg-1), except for soy BYs. The lowest total biogenic amines content was found in fermented rice BYs and ultrasonicated coconut BYs. When comparing untreated and fermented BYs, significant changes in macro- and micro-elements content were found. Ultrasonication at 37 kHz did not significantly influence the concentrations of macro- and micro-elements, while fermentation affected most of the essential micro-elements. Consequently, while ultrasonication and fermentation can enhance the safety of BYs, the specific effects must be taken into account on biogenic amines, mycotoxins, and micro and macro elements.