From Traditional Bulgarian Dairy Products to Functional Foods

Production of the traditional yoghurt, white-brined cheese, and yellow cheese, named “kashkaval”, in the Bulgarian region determines everyday consumption and health benefits for the local population. Аrtisanal dairy products and their autochthonous microbiota are a promising source for the research and creation of new minimally treated, but safe, functional and delicious food. The species from Lactobacillaceae are used in different fermentation technologies, improving the structure, taste, and aroma of the final products. These products possess a prolonged shelf life due to the biopreservative capabilities of the lactic acid bacteria (LAB) strains, their positive health impact, and many physiological functions in the body. This chapter examines the traditional and modern technologies for the production of typical Bulgarian dairy products. Based on the studies of artisanal products, different LAB species from non-starter microbiota are presented, which contribute to the organoleptic qualities of the products and their beneficial properties. The research focus is aimed at the evaluation of various functional characteristics of non-starter strains, such as metabolic activity and food biopreservation. The long-term goal is to study the tradition to create new functional formulas that are the desired and effective factors for health and longevity

Aloe-emodin triggers ROS and Ca 2+ production and decreases the levels of mitochondrial membrane potential of human brain capillary endothelial cells

The aim of this work was to investigate the mechanisms of cytotoxicity of phyto-hydroxyanthraquinone aloe-emodin (AE) on human brain microvascular endothelial cell line hCMEC/D3 and to assess the cellular response in the early stage of treatment in order to extend the knowledge of AE’s anti-angiogenic properties. The immortalized human brain capillary endothelial cells hCMEC/D3 were treated with a series of AE concentrations (5 - 200 μM) for a period of 24 hours. The cell viability was determined by MTS assay. The cellular adenosine triphosphate (ATP) levels were evaluated by CellTiter-Glo® luminescent assay. The intracellular reactive oxygen species (ROS) were determined by 2’,7’-dichlorofluorescein (CM- H2DCFDA) fluorescence assay. The mitochondrial membrane potential (MMP) was assessed using tetramethylrhodamine methyl ester (TMRM) staining, while Fluo-4 was used to measure 2 the intracellular free Ca 2+ concentrations inside living cells analysed by High Content Analysis using the Arrayscan VTI 740. Twenty-four- hour treatment of hCMEC/D3 cells with AE, in concentrations between 50 and 200 µM, decreased the cell viability as well as the intracellular ATP levels in a dose- dependent manner. Increased ROS production and disruption of the mitochondrial membrane potential have also been detected. Notably, AE at a concentration greater than 5 µM dramatically increased intracellular calcium levels. Our results collectively indicate that AE inhibits proliferation of human brain microvascular cells via a mechanism involving ROS generation, disruption of Ca 2+ homeostasis and mitochondrial damage

Lactic Acid Production by <i>Lactiplantibacillus plantarum</i> AC 11S—Kinetics and Modeling

Lactic acid is a versatile chemical with wide application in many industries. It can be produced by the fermentation of different sugars by various lactobacilli and investigations on lactic acid production from different substrates and by different strains are still in progress. The present study aimed to study lactic acid production from lactose by Lactiplantibacillus plantarum AC 11S and to choose a mathematical model describing in the best way the experimental data obtained. The influence of initial substrate concentration was investigated, and optimal pH and temperature were determined. An unstructured mathematical model was developed comprising equations for bacterial growth, substrate consumption, and product formation. The model was solved with different terms for specific growth rates considering substrate and/or product inhibition. The best bacterial growth and lactic acid production were achieved at pH = 6.5 and 30 °C. Production of lactic acid was mainly growth-associated, and at initial substrate concentration over 15 g/L, a considerable product inhibition was observed. The parameters of different models were determined and compared. The modified Gompertz equation gave the best fit when solving only the equation for biomass growth at different initial substrate concentrations. Solving the entire set of differential equations for bacterial growth, substrate consumption, and product formation, the best results were obtained when using a variant of the logistic equation for biomass growth. This variant included a term for product inhibition and described in the best way all experimental data. Solving the model for different biomass concentrations showed that an increase in biomass led to a shorter lag phase and the stationary phase was reached faster. The results obtained, optimum conditions and the kinetic model, are good bases for studying pH-controlled fermentation, as well as a continuous process

Enrofloxacin and Probiotic Lactobacilli Influence PepT1 and LEAP-2 mRNA Expression in Poultry

Expression of peptide transporter 1 (PepT1) and liver-expressed antimicrobial peptide 2 (LEAP-2) in chickens can be influenced by food deprivation, pathological conditions and drug administration. Effect of three putative probiotic Lactobacillus strains and enrofloxacin on the expression of PepT1 and LEAP-2 mRNA was investigated in Ross 308 chickens. One-day-old chicks (n = 24) were allocated to following groups: control (without treatment); group treated with probiotics via feed; group treated with a combination of probiotics and enrofloxacin; and a group given enrofloxacin only. The drug was administered at a dose of 10 mg kg(-1), via drinking water for 5 days. Samples from liver, duodenum and jejunum were collected 126 h after the start of the treatment. Expression levels of PepT1 and LEAP-2 were determined by real-time polymerase chain reaction and were statistically evaluated by Mann-Whitney test. Enrofloxacin administered alone or in combination with probiotics provoked a statistically significant up-regulation of PepT1 mRNA levels in the measured organ sites. These changes can be attributed to a tendency of improvement in utilization of dietary peptide and in body weight gain. LEAP-2 mRNA expression levels did not change significantly in enrofloxacin-treated chickens in comparison with control group

Antimicrobial geopolymer paints based on modified natural zeolite

Many antimicrobial coatings deliver a peak release of antimicrobial agent at an early age, after which they lost antimicrobial activity over time. In the present study a novel geopolymer paints with long term antimicrobial activity were developed based on natural zeolite modified with silver and copper ions. The obtained geopolymer paints were applied by brushing on concrete, ceramic, gypsum paperboard and steel. The coating was characterized by excellent adhesive strength and hiding properties. The long-term antimicrobial effect was evaluated by accelerated aging in carbonation chamber. Microstructural changes were analyzed by powder X-ray diffraction and Fourier transformed infrared spectroscopy. Cytotoxicity, antibacterial, antifungal and virucidal properties were investigated on raw and carbonated geopolymer paints. Geopolymer paints based on modified natural zeolite seems promising antimicrobial coating material that can be implemented in the global fight against the spread of diseases and pathogens