Tomasz Tarko

Interaction of dietary compounds, especially polyphenols, with the intestinal microbiota: a review

The intestinal microbiome plays an important role in the metabolism of chemical compounds found within food. Bacterial metabolites are different from those that can be generated by human enzymes because bacterial processes occur under anaerobic conditions and are based mainly on reactions of reduction and/or hydrolysis. In most cases, bacterial metabolism reduces the activity of dietary compounds; however, sometimes a specific product of bacterial transformation exhibits enhanced properties. Studies on the metabolism of polyphenols by the intestinal microbiota are crucial for understanding the role of these compounds and their impact on our health. This review article presents possible pathways of polyphenol metabolism by intestinal bacteria and describes the diet-derived bioactive metabolites produced by gut microbiota, with a particular emphasis on polyphenols and their potential impact on human health. Because the etiology of many diseases is largely correlated with the intestinal microbiome, a balance between the host immune system and the commensal gut microbiota is crucial for maintaining health. Diet-related and age-related changes in the human intestinal microbiome and their consequences are summarized in the paper.

The profile of volatile compounds and polyphenols in wines produced from dessert varieties of apples.

The aim of this study was to determine the influence of apple variety (Šampion, Idared and Gloster) on the polyphenol profile, volatile composition and sensory characteristics of apple wines. Apples were harvested from the orchard in Garlica Murowana (Poland) and the experiments were conducted on a laboratory scale. Statistically significant differences were detected in the chemical composition of the analyzed wines. The highest antioxidant activity was found in Šampion wines, which was associated with a relatively high concentration of chlorogenic acid and procyanidins. These samples also contained high amounts of acetaldehyde, ethyl acetate and methanol. Idared wines showed a similar polyphenol profile, but they had lower antioxidant capacity and were characterized by a high level of butanol and acetic acid. Gloster wines were distinguished from other samples by a lower concentration of polyphenols and higher concentration of fusel alcohols. During sensory evaluation, wines produced from Idared apples scored the highest value for overall quality.

Influence of prefermentative treatments and fermentation on the antioxidant and volatile profiles of apple wines.

The aim of this study was to determine the influence of different factors such as fruit processing, pectinolytic enzyme application, strain of yeast (Johannisberg-Riesling, Steinberg), cell immobilization on the alginate, and type of fermentation on the antioxidant profile and volatile composition of apple wines. Champion and Idared apples were used during experiments. The factors used influenced significantly (p < 0.05) antioxidant capacity, polyphenol profile, and volatile composition of apple wines. Pulp fermentation caused formation of higher amounts of ethanol and favorably influenced the antioxidant activity of wines. Procyanidins B2 and C1 as well as epicatechin and catechin prevailed among polyphenols in these samples. Cell immobilization positively affected the ethanol content, but decreased the antioxidant activity, of wines. Volatile composition of wines was mainly influenced by strain of yeast and type of fermentation. Apple wines fermented spontaneously were characterized by more esters and methanol and fewer higher alcohols compared to inoculated samples.

Chaenomeles japonica, Cornus mas, Morus nigra fruits characteristics and their processing potential.

The aim of this study was to determine the suitability of Japanese quince (Chaenomeles japonica), cornelian cherry (Cornus mas) and black mulberry (Morus nigra) fruits as raw materials for processing. All analyzed fruits were characterized by high antioxidant activity and total phenolic content. Fruits of Japanese quince and cornelian cherry had also high acidity. Products such as fruit wines and liquors were prepared from the tested fruits. In respect of soluble solid content and reducing sugars content the obtained wine should be classified as dry wines. All analyzed liquors were characterized by similar alcohol content and the soluble solid content. Moreover, liquors made from Japanese quince and cornelian cherry were characterized by high total acidity and antioxidant capacity. The results of sensory analysis showed high commercial potential of the examined fruits.

The immobilization of Arthrospira platensis biomass in different matrices—A practical application for lead biosorption

The biosorption of lead by cyanobacteria (Arthrospira platensis) immobilized in different matrices was studied. This was the first time that sodium alginate, silica gel and agarose beads have been used for the removal of lead from solutions of the metal in concentrations ranging from 50 to 500 mg/L. The effect of pH in the range 4.0 to 5.5 on lead removal was also investigated. For the best biosorbent chosen from those mentioned above, lead biosorption in samples of real wastewater was examined. The maximum biosorption capacities (q) for cells immobilized in alginate, agarose and silica gel were 424.99 ± 16.73, 272.66 ± 7.54 and 2.68 ± 0.25 mg Pb/g dry matter of biosorbent, respectively. The initial pH of the solution as well as initial Pb(II) concentration had an influence on metal uptake. The highest lead sorption by alginate and agarose immobilized cells was reported at pH 5 and at initial lead concentration of 500 mg/L, while sorption by silica immobilized cells was the most effective at pH 4 and initial concentration of 100 mg Pb(II)/L. The reported lead uptake (about 165 mg/g dry weight) by cyanobacterial cells entrapped in sodium alginate was higher in real wastewater than in simulated wastewater of the same initial lead concentration. The results revealed that this new biosorbent system can be a promising candidate for eliminating Pb(II) from wastewater, and more detailed research should be carried out.

The use of fruit extracts for production of beverages with high antioxidative activity

Free radicals and reactive oxygen species can cause many diseases of the circulatory and nervous system as well as tumors. There are many ways of preventing and treating these diseases including the consumption of products that contain significant amounts of antioxidant compounds, such as polyphenols and antioxidative vitamins. However, currently food stores offer mainly convenient food, ready-to-eat foodstuffs or highly processed products. During numerous technological treatments they have been deprived of many valuable compounds occurring in fresh products. Therefore, an important element of the food production technology is to ensure a proper composition of valuable human health-promoting compounds, mostly vitamins, minerals and polyphenols in final food product. Consumers often and willingly drink beverages. They are also a good starting base for supplementation. Drinks can be enriched with polyphenols, which may reduce the risk of lifestyle diseases, owing to their antiradical potential. The aim of this study was to use the fruit extracts for beverages enrichment in order to increase their antioxidative potential and polyphenol content. For the experiment the fruits of Cornelian cherry, lingonberry, elderberry, hawthorn and Japanese quince were used. Fruit was extracted with 80% ethanol, and then thickened by distillation under reduced pressure. Extracts were used to enrich the apple, orange and grapefruit beverages. Antioxidative activity and total polyphenols content in final beverages were determined. Also, sensory analysis was carried out. The fortification of tested beverages resulted in an increased antioxidative activity and total polyphenol content in case of all applied fruit extracts. Among the beverages composed, the best antioxidative properties were found in a beverage of red grapefruit, whereas the best organoleptically evaluated was the orange beverage. The scores of on the sensory evaluation revealed that the addition of extracts from Japanese quince fruit (in the case of apple and orange beverages) and lingonberry extract (grapefruit beverage) were preferred than the other samples.

Characterisation of Antimicrobial Properties of Extracts of Selected Medicinal Plants

The scope of the experiments included analysis of the antimicrobial activity of ethanolic, methanolic and aqueous extracts against bacterial and fungal cultures and determination of the minimum inhibitory concentration of plant extracts tested microbial growth. Analysis of the antifungal and antibacterial activity was carried out by the disc diffusion method using paper discs. In the experiment 11 species of microorganisms - 8 bacterial and 3 fungal strains were used. The highest antimicrobial activity against the tested strains was demonstrated by black elder (Sambucus nigra L.), black locust (Robinia pseudoacacia L.) and lingonberry (Vaccinium vitis-idaea L.) extracts. The study showed the diverse morphological activity of specific parts of elderberry and quince, which is the effect of different polyphenolic profile of these plants. The yeast Saccharomyces cerevisiae, Escherichia coli, Pseudomonas putida and Bacillus subtilis showed the highest sensitivity to the effect of extracts of the analysed plants. As a positive control three antibiotics - amphotericin B, vancomycin and amoxicillin with clavulanic acid were used.

Influence of Selected Saccharomyces and Schizosaccharomyces Strains and Their Mixed Cultures on Chemical Composition of Apple Wines: Yeast strain influence on apple wine quality…

Currently in apple winemaking, pure cultures of Saccharomyces cerevisiae and S. bayanus strains are mainly used. The aim of this study was to determine the influence of Saccharomyces cerevisiae (Johannisberg Riesling - LOCK 105), S. bayanus (DSMZ 3774), S. paradoxus (CBS 7302), and Schizosaccharomyces pombe (DSMZ 70576) applied in pure and mixed cultures on the chemical composition and sensory profile of apple wines. Pasteurized Gloster apple musts with addition of sucrose (up to 22°Blg) were inoculated with specific volume (0.6 g dry weight per liter) of yeast pure or mixed cultures (in a ratio of 1:1, 1:1:1, or 1:1:1:1) and fermented for 28 d at 22 °C. The influence of pure/mixed culture on the chemical composition, volatile profile, and sensory properties of apple wines was determined using high-performance liquid chromatography (HPLC) and gas chromatography (GC) methods. All pure culture of yeasts used for the apple wines production are characterized by good enological profiles. S. bayanus and Sch. pombe are the most distinct to S. cerevisiae. S. bayanus strain increases the level of malic acid and carbonyl compounds in apple wines, whereas Sch. pombe highly deacidifies it and produces the most of glycerol, esters, and acetic acid. The wines obtained with these 2 species gained also, respectively, the best and the worse notes during sensory analysis. Mixed cultures (in most cases) produce greater amounts of ethanol, methanol, and volatile esters compared to pure cultures. The presence of S. bayanus in the mixed culture is beneficial for the quality of apple wines. PRACTICAL APPLICATION Good understanding of the properties of yeasts and the procedures for their selection will make it easier to find strains that could improve the quality of wine. Since wine is formed by the action of a number of species and strains of yeasts, many authors have studied the effect of mixed cultures on the final quality of the product. Most of this research was focused on the effect of the inoculation of Saccharomyces yeast with other species on the aroma of wine. However, there is a little data on the fermentation using simultaneous inoculation of different strains of S. cerevisiae.

The effect of apple cultivars and yeast strains on selected quality parameters and antioxidant activity of fermented apple beverages

ABSTRACT The aim of the study was to evaluate the impact of selected apple cultivars (Rubin, Topaz, Elise) and selected strains of wine, cider, distiller yeast, and wild-type yeast on the dynamics of the fermentation process as well as on the chemical composition and antioxidant properties (AOX) of fermented apple beverages. The quality parameters of the fermented beverages depend mainly on the apple cultivar used. The beverages from the Rubin cultivar met all the requirements for fruit wines, but in the beverages from the Topaz cultivar, the limit values for total acidity were exceeded (> 7g/L). The beverages from the Elise cultivar were characterized by low ethanol content and degree of fermentation. The process of fermentation resulted in a reduction of the total polyphenol content (TPC) in the beverages of the Rubin and Topaz cultivars, while in beverages from the Elise cultivar, in an increase of both TPC and AOX. Abbreviations: AOX - antioxidant activity; TPC - total polyphenol content; FAN - free amino nitrogen; ABTS - diammonium salt of the 2,2ʹ-azino-bis(3-ethylbenzothiazoline-6-sulfonic) acid.