RESUMO
The aim of this study was to obtain drinking yogurts enriched with ACTICOA cocoa powder (ACTICOA), its extract (EACTICOA) and pure phenolics, as well as their inclusion complexes with cyclodextrins and alginate-chitosan (A-Ch) capsules, and to evaluate the effects of these additives on the viability of lactic acid bacteria (LAB) and antioxidant properties of fresh yogurts and yogurts stored for 14 days at 4 °C. The application of cocoa phenolic compounds in free form and in the form of EACTICOA to yogurts resulted in the greatest increase in the concentration of phenolic compounds and a significant improvement in the antioxidant properties of the fortified products. The highest TPC was found in yogurts enriched with free quercetin (107.98 mg CE/g). Yogurt fortified with free gallic acid showed the highest ability to neutralize free radicals (EC50 = 2.74 mg/mg DPPH, EC50 = 5.40 mg/mg ABTS) and reduce ferric ions (183.48 µM Trolox/g). The enrichment of yogurts with the tested phenolic compounds preparations, especially in the form of encapsulates, did not affect the viability of LAB during storage.
Assuntos
Antioxidantes , Cacau , Lactobacillales , Fenóis , Iogurte , Iogurte/microbiologia , Iogurte/análise , Antioxidantes/farmacologia , Antioxidantes/química , Fenóis/análise , Fenóis/farmacologia , Fenóis/química , Cacau/química , Lactobacillales/crescimento & desenvolvimento , Alimentos Fortificados/análise , Quitosana/química , Quitosana/farmacologia , Alginatos/química , Alginatos/farmacologia , Extratos Vegetais/farmacologia , Extratos Vegetais/química , CápsulasRESUMO
The encapsulation of insoluble compounds can help improve their solubility and activity. The effects of cyclodextrin encapsulation on hesperetin's derivatives (HHSB, HIN, and HTSC) and the physicochemical properties of the formed complexes were determined using various analytical techniques. The antioxidant (DPPHâ¢, ABTSâ¢+ scavenging, and Fe2+-chelating ability), cytotoxic, and antibacterial activities were also investigated. The inclusion systems were prepared using mechanical and co-evaporation methods using a molar ratio compound: HP-ß-CD = 1:1. The identification of solid systems confirmed the formation of two inclusion complexes at hesperetin (CV) and HHSB (mech). The identification of systems of hesperetin and its derivatives with HP-ß-CD in solutions at pHs 3.6, 6.5, and 8.5 and at various temperatures (25, 37 and 60 °C) confirmed the effect of cyclodextrin on their solubility. In the DPPH⢠and ABTSâ¢+ assay, pure compounds were characterized by higher antioxidant activity than the complexes. In the FRAP study, all hesperetin and HHSB complexes and HTSC-HP-ß-CD (mech) were characterized by higher values of antioxidant activity than pure compounds. The results obtained from cytotoxic activity tests show that for most of the systems tested, cytotoxicity increased with the concentration of the chemical, with the exception of HP-ß-CD. All systems inhibited Escherichia coli and Staphylococcus aureus.
Assuntos
Antioxidantes , Ciclodextrinas , 2-Hidroxipropil-beta-Ciclodextrina/química , Antioxidantes/farmacologia , Antioxidantes/química , Ciclodextrinas/farmacologia , Ciclodextrinas/química , SolubilidadeRESUMO
The aim of the study was to determine the effect of osmoconcentration in a sucrose and sodium chloride solution on the efficiency of lactic fermentation and the content of polyphenols and oligosaccharides in yellow and red onion varieties: Alonso, Hysky, Hystore, and Red Lady. In most cases, no negative effect of onion dehydration was noted on the growth or number of the bacteria tested. Osmotic dehydration of onions prior to lactic fermentation may positively modify the profile of lactic acid isomers by increasing the proportion of the L (+) isomer. The use of osmotic dehydration before fermentation did not adversely affect the content of polyphenols in the onions. Simultaneously, the loss of fructo-oligosaccharides was limited: 60 % of the initial fructo-oligosaccharide content was obtained using the Alonso cultivar and Levilactobacillus brevis 0944 for onion fermentation.
Assuntos
Ácido Láctico , Cebolas , Fermentação , Humanos , Oligossacarídeos , PolifenóisRESUMO
Microorganisms are able to give rise to biofilm formation on food matrixes and along food industry infrastructures or medical equipment. This growth may be reduced by the application of molecules preventing bacterial adhesion on these surfaces. A new Schiff base ligand, derivative of hesperetin, HABH (2-amino-N'-(2,3-dihydro-5,7-dihydroxy-2-(3-hydroxy-4-methoxyphenyl)chromen-4-ylidene)benzohydrazide), and its copper complex, CuHABH [CuLH2(OAc)], were designed, synthesized and analyzed in terms of their structure and physicochemical properties, and tested as antibacterial agents. Their structures both in a solid state and in solution were established using several methods: FT-IR, 1H NMR, 13C NMR, UV-Vis, FAB MS, EPR, ESI-MS and potentiometry. Coordination binding of the copper(II) complex dominating at the physiological pH region in the solution was found to be the same as that detected in the solid state. Furthermore, the interaction between the HABH and CuHABH with calf-thymus DNA (CT-DNA) were investigated. These interactions were tracked by UV-Vis, CD (circular dichroism) and spectrofluorimetry. The results indicate a stronger interaction of the CuHABH with the CT-DNA than the HABH. It can be assumed that the nature of the interactions is of the intercalating type, but in the high concentration range, the complex can bind to the DNA externally to phosphate residues or to a minor/major groove. The prepared compounds possess antibacterial and antibiofilm activities against Gram-positive and Gram-negative bacteria. Their antagonistic activity depends on the factor-strain test system. The glass was selected as a model surface for the experiments on antibiofilm activity. The adhesion of bacterial cells to the glass surface in the presence of the compounds was traced by luminometry and the best antiadhesive action against both bacterial strains was detected for the CuHABH complex. This molecule may play a crucial role in disrupting exopolymers (DNA/proteins) in biofilm formation and can be used to prevent bacterial adhesion especially on glass equipment.
Assuntos
Antibacterianos , Complexos de Coordenação , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Positivas/crescimento & desenvolvimento , Hesperidina , Hidrazonas , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , Cobre/farmacologia , Hesperidina/química , Hesperidina/farmacologia , Hidrazonas/química , Hidrazonas/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
In this study, the blueberries (BLUB), raspberries (RASB), blackberries (BLCB), pomegranates pomace (POME) and beetroots (BEET) freeze-dried powders were used as the sources of phenolic compounds to enrich different types of chocolates, substituting a part of the sweetener. It was found that 1% addition of fruit or vegetable powders to chocolates increased the content of total phenolic compounds (flavan-3-ols, phenolic acids and anthocyanins) of enriched dark and milk chocolates compared to the control ones dependent on the powder used. Among the enriched chocolates, the chocolates with the addition of BLUB powder were characterized by the highest total polyphenol content. The highest percentage increase (approximately 80%) in the total polyphenol content was observed in MCH chocolate enriched with BLUB powder. Chocolates incorporated with BLUB, RASB, BLCB and POME powders presented a richer phenolic compound profile than control counterparts. The highest DPPH radical-scavenging capacity was exhibited by the DCH98S chocolate enriched with BEET powder. However, the DCH98ESt chocolates enriched with POME and BEET powders demonstrated the highest FRAP values. An electronic nose analysis confirmed the existence of differences between the profiles of volatile compounds of various types of chocolates enriched with fruit or vegetable powders. Thus, the enrichment of dark and milk chocolates with BLUB, RASB, BLCB, POME and BEET powders seemed to be an interesting approach to enhance bioactivity and to enrich the sensory features of various chocolate types.
Assuntos
Antioxidantes/química , Chocolate , Antioxidantes/análise , Cacau/química , Liofilização , Frutas/química , PósRESUMO
Due to their richness of bioactive substances, rose hips are a valuable raw material for obtaining extracts with potential antimicrobial activity. The aim of the study was to determine the antagonistic potential of whole pseudo-fruit and flesh extracts of three Rosa sp. varieties against Staphylococcus spp. bacteria isolated as food contaminants. The biological material in this study consisted of seven strains of bacteria from the genus Staphylococcus. Two strains-Staphylococcus aureus ATCC 25923 and Staphylococcus epidermidis DSMZ 3270-were used as reference strains. The other five strains were food-derived isolates-S. epidermidis A5, S. xylosus M5, S. haemolyticus M6, S. capitis KR6, and S. warneri KR2A. The material was the pseudo-fruits of Rosa canina, Rosa pomifera Karpatia, and Rosa rugosa. The polyphenols were extracted from the fleshy part and the whole pseudo-fruit for all rose varieties. The tested preparations differed significantly in their polyphenol composition. The sum of polyphenols ranged from 28â 862 to 35â 358 mg/100 g of lyophilisate. The main groups of polyphenols found in the preparations were flavanols and ellagitannins. All of the tested extracts inhibited the growth of staphylococci at a concentration of 500 mg/mL. Rosa rugosa fruit extract showed the strongest antimicrobial properties among the studied extracts. For all the strains, the growth inhibition had a diameter of 20.3-29.0 mm. Moreover, six out of the seven tested strains showed the highest inhibition with the use of this extract. The MIC of rose extracts was in the range of 3.125-500 mg/mL and was strictly dependent on the bacterial species, the species of the rose, and the part of the fruit from which the extract was obtained. Correlations were assessed between the main groups of polyphenols in the extracts and their inhibition of bacterial growth. In the case of pseudo-fruit extracts, the inhibitory effect on bacterial growth positively correlated with the content of ellagitannins, and this effect was observed for almost all the tested strains. The results presented herein follow the current trend of minimising the use of chemical preservatives in food; from this point of view, rose extracts are very promising.
Assuntos
Antibacterianos/química , Flavonoides/química , Taninos Hidrolisáveis/química , Polifenóis/química , Rosa/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Contaminação de Alimentos/prevenção & controle , Microbiologia de Alimentos/métodos , Frutas/química , Humanos , Taninos Hidrolisáveis/isolamento & purificação , Taninos Hidrolisáveis/farmacologia , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Polifenóis/isolamento & purificação , Polifenóis/farmacologia , Staphylococcus/efeitos dos fármacos , Staphylococcus/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus capitis/efeitos dos fármacos , Staphylococcus capitis/crescimento & desenvolvimento , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Staphylococcus haemolyticus/efeitos dos fármacos , Staphylococcus haemolyticus/crescimento & desenvolvimentoRESUMO
Yeasts have a substantial impact on the contamination and loss of food. In this study, we applied bacteria of the genus Lactobacillus as natural biopreservatives. Anticandidal strains of bacteria were selected from among 60 strains of bacteria grown which were each with nine polyols or galactosyl polyols. Polyols and galactosyl polyols can act as prebiotics for lactic acid bacteria and can enhance the antifungal properties of bacteria by affecting their metabolism. The galactosyl polyols significantly improved the anticandidal activity of most of the bacteria we tested. Based on the screening, the most promising strains of bacteria were selected, and their metabolites (both primary and secondary) and enzymatic activity were characterized in the presence of polyols and galactosyl polyols. The qualitative and quantitative content of bacterial metabolites depended both on the bacterial strain and the type of culture medium. A wide variety of antifungals produced by bacteria, such as fatty acids, hydroxy fatty acids, and other acidic products with potential antagonistic activity (phenyllactic acid or hydroxyphenyllactic acid) were detected. The bacteria produced a high concentration of phenyllactic acid in the presence of galactosyl polyols (up to 84.3 mg/L). This finding could suggest that this metabolite may have a significant impact on the antifungal properties of lactobacilli against yeast. Galactosyl polyols influenced the enzymes involved in the synthesis of fatty acids and hydroxylated fatty acids (esterase lipase, acid phosphatase, and α-glucosidase). The mechanism of the antifungal effect of lactobacilli may be based on the synergistic effect of their primary and secondary metabolites, in particular phenyllactic acid.
Assuntos
Antifúngicos/metabolismo , Antifúngicos/farmacologia , Lactobacillus/metabolismo , Polímeros/metabolismo , Polímeros/farmacologia , Meios de Cultura , Ácidos Graxos , Fermentação , Microbiologia de Alimentos , Lactatos/metabolismo , Ácido Láctico/metabolismo , Lactobacillales , Polímeros/química , Metabolismo SecundárioRESUMO
The aim of this study was to evaluate the effect of the algae Chlorella vulgaris on the growth, acidifying activity, proportion of lactic acid isomers, and enzymatic profile of Lactobacillus brevis (LOCK 0944, LOCK 0980, LOCK 0992, and MG451814) isolated from vegetable silages. The results indicated that adding algae at concentrations of 0.1% (w/v) and 1.5% (w/v) to the Lactobacillus spp. growth medium accelerated the growth of bacteria and thus shortened their phase of logarithmic growth. The acidifying activity of the tested Lactobacillus brevis increased with an increased concentration of algae. Lactobacillus spp. cultured in the presence of Chlorella vulgaris showed higher production of l-lactic acid and lower d-lactic acid production. Moreover, the addition of algae changed the enzymatic activity of lactic acid bacteria; for instance, Lactobacillus brevis LOCK 0980 demonstrated more enzymatic activity of valine arylamidase, α-galactosidase, and α-glucosidase. Combining Lactobacillus brevis with the algae Chlorella vulgaris allows for the creation of innovative, functional products which confer favorable properties to the final product and open new horizons for the food industry.
RESUMO
Growth media composition is a critical factor influencing the yield of bacterial exopolysaccharides (EPSs), which have attracted the interest of researchers around the world due to their diverse physicochemical and biological properties. This work presents the optimization of media for EPS synthesis by three Lactobacillus rhamnosus strains, namely LOCK 0943, LOCK 0935, and OM-1. The optimized media led to a more than 13-fold increase in EPS yield for L. rhamnosus LOCK 0943 (from 85 to 1138.2 mg/L), an almost 9-fold increase for L. rhamnosus LOCK 0935 (from 103.67 to 900 mg/L), and a more than 7-fold increase for L. rhamnosus OM-1 (from 133.67 to 987.84 mg/L) as compared to cultures in standard MRS medium (de Man, Rogosa, and Sharpe). It has been found that the main medium-related determinant of EPS synthesis by the studied L. rhamnosus strains are the carbon source-in this case, it was fructose and sucrose.
Assuntos
Meios de Cultura/química , Lacticaseibacillus rhamnosus , Polissacarídeos Bacterianos/biossíntese , Carbono/metabolismo , Lacticaseibacillus rhamnosus/crescimento & desenvolvimento , Lacticaseibacillus rhamnosus/metabolismoRESUMO
Legume seeds and sprouts are a rich source of phytoestrogens in the form of isoflavonoids. For the first time, lactic acid fermentation of four types of legume sprouts was used to increase the content of isoflavonoids and microbiological safety. After germination, the highest content of isoflavonoids was observed in the clover and chickpea sprouts, which amounted to 1.1â¯g/100â¯g dw., whereas the lactic acid fermentation allowed the increase to as much as 5.5â¯g/100â¯g dw. The most beneficial properties were shown by fermented chickpea sprouts germinated in blue light. During fermentation the number of lactic acid bacteria increased by 2 Log10 CFU/mL (LU), whereas mold decreased by 1 LU, E. coli and Klebsiella sp. by 2 LU, Salmonella sp. and Shigella sp. did not occur after fermentation, similar to Staphylococcus epidermidis, while S. aureus and S. saprophyticus decreased by 3 LU and in some trials were not detected.
Assuntos
Fabaceae/microbiologia , Microbiologia de Alimentos/métodos , Isoflavonas/metabolismo , Lactobacillales/metabolismo , Sementes/microbiologia , Escherichia coli/patogenicidade , Fabaceae/metabolismo , Fermentação , Germinação , Fitoestrógenos/metabolismo , Salmonella/patogenicidade , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Staphylococcus aureus/patogenicidadeRESUMO
Algae are common all over the Earth. Due to their rich chemical composition and content of bioactive substances they have been used in many fields of industry. Their gelling, thickening and stabilizing properties have led to the development of such products as agar, alginate and carrageenan. Moreover, algae are used in the food industry as food supplements and an addition to functional food. Algae are also added to meat products, such as pasty, steaks, frankfurters and sausages, as well as to fish, fish products, and oils, to improve their quality. Cereal-based products, such as pasta, flour and bread, are another group of products enriched with algae. Due to their properties algae may also be used for construction of fermented functional food. Fermented products containing algae are, most of all, dairy products, such as cheese, cream, milk deserts, yoghurt, cottage cheese, and processed cheese. Combination of fermented products offering a high content of lactic acid bacteria with algae possessing biologically active metabolites of natural origin allows not only to compose products with a high content of nutrients, but also to create a brand new segment of fermented food.
Assuntos
Alimentos , Alga Marinha , Ágar , Alginatos , Animais , Carragenina , Queijo , Lactobacillales , Produtos da Carne , Leite , IogurteRESUMO
Lactobacillus sp. synthesize exopolysaccharides (EPS), including both homo- and heteropolysaccharides, which play an important role in the production of fermented foods, and especially in the dairy industry, improving the gustatory and rheological properties of the finished products. These polymers are generated by starter cultures in situ in fermented foods, and so they are treated as natural thickening agents. As some Lactobacillus strains are generally recognized as safe and have been shown to exhibit probiotic activity, EPS from those bacteria can be used as functional food ingredients, conferring both health and economic benefits to the consumers. However, their industrial applications are hindered by the low yield of EPS from Lactobacillus and high costs of their purification. This review focuses on the latest reports concerning the biosynthesis and properties of Lactobacillus EPS.
Assuntos
Lactobacillus/metabolismo , Polissacarídeos Bacterianos/biossíntese , Configuração de Carboidratos , Tecnologia de Alimentos , Humanos , Polissacarídeos Bacterianos/química , ProbióticosRESUMO
Fisetin (3,3',4',7-tetrahydroxyflavone) metal chelates are of interest as this plant polyphenol has revealed broad prospects for its use as natural medicine in the treatment of various diseases. Metal interactions may change or enhance fisetin biological properties so understanding fisetin metal chelation is important for its application not only in medicine but also as a food additive in nutritional supplements. This work was aimed to determine and characterize copper complexes formed in different pH range at applying various metal/ligand ratios. Fisetin and Cu(II)-fisetin complexes were characterized by potentiometric titrations, UV-Vis (Ultraviolet-visible spectroscopy), EPR, ESI-MS, FTIR and cyclic voltammetry. Their effects on DNA were investigated by using circular dichroism, spectrofluorimetry and gel electrophoresis methods. The copper complex with the ratio of Cu(II)/fisetin 1/2 exhibited significant DNA cleavage activity, followed by complete degradation of DNA. The influence of copper(II) ions on antioxidant activity of fisetin in vitro has been studied using DPPH, ABTS and mitochondrial assays. The results have pointed out that fisetin or copper complexes can behave both as antioxidants or pro-oxidants. Antimicrobial activity of the compounds has been investigated towards several bacteria and fungi. The copper complex of Cu(II)/fisetin 1/2 ratio showed higher antagonistic activity against bacteria comparing to the ligand and it revealed a promising antifungal activity.
Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/química , Quelantes/química , Cobre/química , DNA/química , Flavonoides/química , Anti-Infecciosos/química , Antioxidantes/farmacologia , Quelantes/farmacologia , Cobre/farmacologia , Eletroforese em Gel de Poliacrilamida , Flavonoides/farmacologia , Flavonóis , Concentração de Íons de Hidrogênio , Análise Espectral/métodosRESUMO
The antifungal activity of Lactobacillus pentosus LOCK 0979 depends both on the culture medium and on the fungal species. In the control medium, the strain exhibited limited antagonistic activity against indicator food-borne molds and yeasts. However, the supplementation of the bacterial culture medium with polyols (erythritol, lactitol, maltitol, mannitol, sorbitol, xylitol) or their galactosyl derivatives (gal-erythritol, gal-sorbitol, gal-xylitol) enhanced the antifungal properties of Lactobacillus pentosus LOCK 0979. Its metabolites were identified and quantified by enzymatic methods, HPLC, UHPLC-MS coupled with QuEChERS, and GC-MS. The presence of polyols and gal-polyols significantly affected the acid metabolite profile of the bacterial culture supernatant. In addition, lactitol and mannitol were used by bacteria as alternative carbon sources. A number of compounds with potential antifungal properties were identified, such as phenyllactic acid, hydroxyphenyllactic acid, and benzoic acid. Lactobacillus bacteria cultivated with mannitol synthesized hydroxy-fatty acids, including 2-hydroxy-4-methylpentanoic acid, a well-described antifungal agent. Scanning electron microscopy (SEM) and light microscopy confirmed a strong antifungal effect of L. pentosus LOCK 0979.
Assuntos
Antifúngicos/metabolismo , Lactobacillus pentosus/química , Lactobacillus pentosus/metabolismo , Polímeros/metabolismo , Antifúngicos/química , Meios de Cultura/química , Meios de Cultura/metabolismo , Fermentação , Lactobacillus pentosus/crescimento & desenvolvimento , Manitol/análise , Manitol/metabolismo , Espectrometria de Massas , Polímeros/química , Álcoois Açúcares/análise , Álcoois Açúcares/metabolismoRESUMO
Bionic acids are bioactive compounds demonstrating numerous interesting properties. They are widely produced by chemical or enzymatic oxidation of disaccharides. This paper focuses on the galactosyl derivative of gluconic acid as a result of a new method of bionic acid synthesis which utilises the transglycosylation properties of ß-galactosidase and introduces lactose as a substrate. Products obtained in such a process are characterised by different structures (and, potentially, properties) than those resulting from traditional oxidation of disaccharides. The aim of this study is to determine the effect of selected parameters (concentration and ratio of substrates, dose of the enzyme, time, pH, presence of salts) on the course of the reaction carried out with the enzymatic preparation Lactozym, containing ß-galactosidase from Kluyveromyces lactis. Research has shown that increased dry matter content in the baseline solution (up to 50%, by mass per volume) and an addition of NaCl contribute to higher yield. On the other hand, reduced content of the derivative is a result of increased pH from 7.0 to 9.0 and an addition of magnesium and manganese salts. Moreover, exceeding the ß-galactosidase dose over approx. 35 000 U per 100 g of lactose also leads to reduced yield of the process. The most favourable molar ratio of sodium gluconate to lactose is 2.225:0.675. Depending on the conditions of the synthesis, the product concentration ranged between 17.3 and 118.3 g/L of the reaction mixture, which corresponded to the mass fraction of 6.64-23.7% of dry matter. The data obtained as a result of the present study may be useful for designing an industrial process.
RESUMO
Lactobacillus strains can synthesize capsular polysaccharides (CPS), which are important substances in the dairy industry-they exhibit many important technological as well as health-promoting properties. Technological advancements have made it possible to detect bacterial capsules using costly and labor-intensive methods, such as serological reactions, molecular genetic techniques, and electron microscopy. Light microscopy, which is the method of interest in this paper, is one of the most widely accessible and cheapest techniques. CPS may be observed under a light microscope after staining bacterial cells and the background with a basic die and an acidic die, respectively (negative-positive staining), with the capsules remaining transparent. The literature offers many polysaccharide staining methods, but due to the considerable structural diversity of CPS and possible dye-capsule interactions, a suitable staining technique should be carefully selected for each strain. The current study showed that not all methods adequately reveal Lactobacillus CPS, with the most effective ones being those proposed by Hiss and Maneval.
Assuntos
Cápsulas Bacterianas/química , Lactobacillus/química , Polissacarídeos Bacterianos/biossíntese , Laticínios/microbiologia , Microbiologia de AlimentosRESUMO
Ellagitannins possess several biological activities, including anticancer properties. The goal of the present study was to investigate the cyto- and genotoxic activities of a red raspberry ellagitannin preparation (REP) in the concentration range of 2.5-160 µg/mL, as well as that of the main individual raspberry ellagitannins, sanguiin H-6 (SH-6, 12.8-256 µM) and lambertianin C (LC, 9.3-378 µM), against human colon adenocarcinoma cell line Caco-2. The ellagitannin concentrations used in the study correspond to those found in foodstuffs containing raspberry fruit. REP, SH-6, and LC exhibited strong concentration-dependent genotoxic properties, inducing DNA damage ranging from 7.3 ± 1.3 to 56.8 ± 4.3%, causing double-strand breaks and oxidation of DNA bases. At IC50 (124 µg/mL) the REP affected the nuclear morphology and induced the apoptosis of Caco-2 cells. Because the REP has been found to possess chemopreventive activity, it can be used as a natural food additive to enhance the health benefits of foodstuffs.
Assuntos
Antibacterianos , Antifúngicos , Bactérias/crescimento & desenvolvimento , Complexos de Coordenação , Cobre , Flavanonas , Fungos/crescimento & desenvolvimento , Tiossemicarbazonas , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Linhagem Celular Tumoral , Complexos de Coordenação/sangue , Complexos de Coordenação/farmacologia , Cobre/química , Cobre/farmacologia , DNA/química , Flavanonas/química , Flavanonas/farmacologia , Células HEK293 , Humanos , Albumina Sérica Humana/química , Tiossemicarbazonas/química , Tiossemicarbazonas/farmacologiaRESUMO
The paper presents the chemical characteristics of ellagitannins isolated from raspberry (Rubus idaeus L.) fruit and their in vitro and in situ antifungal activity against Geotrichum candidum LOCK 0511. The study investigated a complex preparation containing various raspberry ellagitannins at a concentration of 86% w/w, as well as pure lambertianin C and sanguiin H-6. The ellagitannin preparation was obtained by extracting raspberry press cake and purifying the extract using Amberlite XAD resin, while individual compounds were isolated by means of preparative HPLC. The complex preparation was analyzed for the content of ellagitannins, anthocyanins, and flavan-3-ols using HPLC and LC-MS. The antifungal activity of the complex ellagitannin preparation and the isolated ellagitannins was determined for the strain Geotrichum candidum. The MIC and MFC values (10.0 mg/mL and 30.0 mg/mL, respectively) were found to be the same for lambertianin C, sanguiin H-6, and the complex ellagitannin preparation. The fungistatic activity of the studied ellagitannin preparation at a concentration of 10 mg/mL, as determined by the poisoned medium method, was 65.2% following 6 day incubation of Geotrichum candidum, with the linear growth rate of only 16.2 mm/day. The corresponding parameters for the control sample were 0% and 56 mm/day, respectively. The study demonstrated both in vitro and in situ antifungal activity of raspberry ellagitannins against Geotrichum candidum.