Biological activity of bacteria isolated from wetland sediments collected from a conservation unit in the southern region of Brazil

Wetlands are ecosystems rich in biodiversity and their ecological importance is recognized worldwide. Sediment samples were subjected to physical-chemical analysis and organic carbon content varied from 3.0% to 4.8%, the clay between 32 and 40%, silt with 41% and 43%, sand coarse varied between 6 and 11% and fi ne sand between 7 and 16%. The nitrogen values varied from 0.25% to 0.48%, the pH from 5.4 to 7.5 and the humidity varied from 44 to 56%. The selected isolates were evaluated for enzymatic properties and 64% showed positive results for amylase, 16% for gelatinase, 37% for lipase, 91% for protease and 2.7% for inulinase. Six bacterial isolates were selected for the overlapping assay and Bacillus sp. sed 2.2 showed inhibitory activity against Corynebacterium fi mi NCTC 7547, and the antimicrobial substance was partially purifi ed. The characterization of the substance was carried and the substance was stable at 100° C for up to 10 minutes and sensitive to the enzymes papain and trypsin. This substance was active against some species of Listeria, including Listeria monocytogenes ATCC 7644. The microorganims obtained from sediment samples were important sources of bioactive compounds, including enzymes and peptides, being a source of bioactive compounds to be studied

Morangos silvestres (Rubus rosifolius Sm.) do sul do Brasil : composição centesimal e mineral, polifenóis, atividades antioxidante, antibacteriana e anti-hipertensiva

The objective of the present work was to evaluate polyphenols, trace elements and compounds with antioxidant, antimicrobial and anti-hypertensive activity in wild strawberries cultivated in Southern Brazil. Fruits present high fiber, iron, potassium and sodium concentrations. Polyphenolic content was 242.12 mg of gallic acid equivalent per 100g and monomeric anthocyanin concentration was 100.50 mg of cyanidin 3-glucoside per 100g. Wild strawberries presented the capacity of scavenging 89% of ABTS•+ radical and 61% of DPPH• radicals and chelating power of 3.1, meanwhile the inhibition of the angiotensin-converting enzyme I activity was 12.5%. Fruits presented compounds with capacity to inhibit Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes and Aeromonas hydrophyla. Thus, wild strawberries are important source of functional compounds and their consumption is a way to promote the Brazilian biodiversity and improve human diet.O objetivo do presente trabalho foi avaliar polifenóis, oligoelementos e compostos com atividade antioxidante, antibacteriana e anti-hipertensiva de morangos silvestres cultivados no sul do Brasil. Os frutos apresentam alta concentração de fibras, ferro, potássio e sódio. O conteúdo polifenólico foi de 242,12 mg de equivalente de ácido gálico por 100 g e a concentração de antocianinas monomérica foi de 100,50 mg de cianidina 3-glucosideo por 100 g. Os morangos silvestres apresentaram capacidade de eliminar 89% dos radicais ABTS•+ e 61% dos radicais DPPH• e poder quelante de 3,1, enquanto a inibição da atividade da enzima conversora de angiotensina I foi de 12,5%. Os frutos apresentaram compostos com capacidade de inibir Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes e Aeromonas hydrophyla. Assim, os morangos silvestres são importantes fontes de compostos funcionais e seu consumo pode ser importante para valorizar a biodiversidade brasileira e promover a variação da dieta humana

Characterization of the antimicrobial activity produced by Bacillus sp. isolated from wetland sediment

Bacteria of the genus Bacillus sp. present the potential for inhibiting various pathogens, making them a promising starting point in the search for new antimicrobial substances. In this study, bacteria were isolated from sediment samples from humid areas of a Natural Conservation Unit in the state of Rio Grande do Sul, Brazil. The isolate Bacillus sp. sed 1.4 was selected for production of antimicrobial activity, and was characterized by MALDI-TOF and 16S rDNA sequencing. Phylogenetic analysis showed that Bacillus sed 1.4 was closely related to Bacillus altitudinis and Bacillus pumilus. The cell-free supernatant was partially purifi ed using ammonium sulfate precipitation, gel fi ltration chromatography (Sephadex G-200) and an ultrafi ltration membrane. Partial purifi cation resulted in specifi c activity of 769.23 AU/mg, with a molecular mass of approximately 148 kDa. This antimicrobial substance showed stability at 100°C for 5 min, and was inactivated by proteolytic enzymes. An antimicrobial effect against Listeria species was observed. Considering the importance of the Listeria genus in the area of food safety, this antimicrobial activity should be further explored, specifi cally in the fi eld of dairy products and with a focus on food biopreservation studies

Thermal resistance of proteolytic enzymes produced by psychrotrophic bacteria isolated from buffalo milk

Background and Objective: Psychrotrophic bacteria produce extracellular proteases, resulting in deterioration and reduced shelf life of dairy products. In this study, 21 species of psychotropic bacteria isolated from buffalo milk were selected and the thermal resistance of the proteases produced by these bacteria was evaluated. Materials and Methods: The isolates were tested to evaluate proteolytic activity of buffalo milk agar. The cell-free supernatants from the growing of isolates were obtained for the quantification of enzymatic activity under different pH values (5.5, 7.0 and 8.0). Thermal resistance and the clotting ability of proteolytic enzymes in buffalo and bovine milk substrates were also evaluated. One-way ANOVA test with a critical probability of p1 U mLG1 under at least one of the pH tested. Five isolates produced cell-free supernatants resistant to pasteurization (63.5EC/30 min), following which they were able to coagulate buffalo and bovine milk. The crude enzyme of P. fluorescens PL5.4 showed the greatest enzymatic activity within a wide pH range (4-10) and at an optimum temperature of 40EC. The cell-free supernatant of this isolate resisted to tests with detergents and organic solvents. However, it was not possible to identify the type of protease. Conclusion: The results of this study showed the negative impact of the presence of psychrotrophic bacteria producing proteolytic enzymes in buffalo milk. This is because the enzymes studied caused changes in milk samples, revealing a negative impact on the production of derived products. This is significant, since the buffalo milk produced in Brazil is directed to the production of dairy products

Determination of the nutritional value of diet containing bacillus subtilis hydrolyzed feather meal in adult dogs

Feathers are naturally made up of non-digestible proteins. Under thermal processing, total tract digestibility can be partially improved. Furthermore, Bacillus subtilis (Bs) has shown a hydrolytic effect In vitro. Then, a Bs FTC01 was selected to hydrolyze enough feathers to produce a meal, and then test the quality and inclusion in the dog’s diet to measure the apparent total tract digestibility coefficient (ATTDC) in vivo and the microorganism’s ability to survive in the gastrointestinal tract. A basal diet was added with 9.09% hydrolyzed Bs feather meal (HFMBs) or 9.09% thermally hydrolyzed feather meal (HFMT). Nine adult dogs were randomized into two 10-day blocks and fed different diets. Microbial counts were performed on feather meal, diets and feces. The Bs was less effective in digesting the feathers, which reduced the ATTDC of dry matter, crude protein, energy and increased the production of fecal DM, but the fecal score was maintained (p > 0.05). The digestible energy of HFMT and HFMBs was 18,590 J/kg and 9196 J/kg, respectively. Bacillus subtilis showed limitation to digest feather in large scale, but the resistance of Bs to digestion was observed since it grown on feces culture

Proteolytic potential of enzymes produced by candida parapsilosis and rhodotorula. Mucilaginosa isolated from liquid whey

The search for yeast with proteolytic activity that can be explored in technology and product innovation was the objective of this study to isolate and identify strains present in liquid whey and evaluate the proteolytic activity of isolates. From the isolated strains were selected for molecular identification, those with proteolytic activity. Verification of proteolytic activity was performed on milk agar and visualized by a translucent halo. Four strains belonging to two yeast species were identified as protease producers. Whey is promising in microbial sources of biotechnological interest and C. parapsilosis (ES01) and R. mucilaginosa (ES04) strains were good protease producers in commercial agar-like milk agar. These results indicate the proteolytic potentiality of strains isolated from whey.Fil: Monte, Aline Marques. Universidade Federal Do Piaui.; BrasilFil: Matos da Silva, Ana Karoline. Universidade Federal Do Piaui.; BrasilFil: Dourado Rodrigues, Aline Maria. Universidade Federal Do Piaui.; BrasilFil: Muratori Costa, Luciana. Universidade Federal Do Piaui.; BrasilFil: Sousa Santos, André Luis. Universidade Federal do Rio de Janeiro; BrasilFil: Gomes Abreu Bacelar, Rafael. Universidade Federal Do Piaui.; BrasilFil: de Sousa Ramos, Lívia. Universidade Federal do Rio de Janeiro; BrasilFil: Folmer Correa, Ana Paula. Universidade Federal de Roraima; BrasilFil: Brandelli, Adriano. Universidade Federal do Rio Grande do Sul; BrasilFil: Pereyra, Carina Maricel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; ArgentinaFil: Sanches Muratori, Maria C.. Universidade Federal Do Piaui.; Brasi

Effects of Achyrocline satureioides inflorescence extracts against pathogenic intestinal bacteria : chemical characterization, in vitro tests, and in vivo evaluation

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared fromthe aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol).The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of antimicrobial activity against intestinal pathogenic bacteria greater than those observed by the antibiotic, amoxicillin, when tested against Bacillus cereus and Staphylococcus aureus. Antioxidant and antimicrobial activities of AS extracts seemed to be positively correlated with the present amount of flavonoids. These findings suggest a potential use of AS as a coadjuvant agent for treating bacterial-induced intestinal diseases with high rates of antibiotic resistance

Effects of Achyrocline satureioides

Three Achyrocline satureioides (AS) inflorescences extracts were characterized: (i) a freeze-dried extract prepared from the aqueous extractive solution and (ii) a freeze-dried and (iii) a spray-dried extract prepared from hydroethanol extractive solution (80% ethanol). The chemical profile, antioxidant potential, and antimicrobial activity against intestinal pathogenic bacteria of AS extracts were evaluated. In vitro antioxidant activity was determined by the total reactive antioxidant potential (TRAP) assay. In vivo analysis and characterization of intestinal microbiota were performed in male Wistar rats (saline versus treated animals with AS dried extracts) by high-throughput sequencing analysis: metabarcoding. Antimicrobial activity was tested in vitro by the disc diffusion tests. Moisture content of the extracts ranged from 10 to 15% and 5.7 to 17 mg kg−1 of fluorine. AS exhibited antioxidant activity, especially in its freeze-dried form which also exhibited a wide spectrum of antimicrobial activity against intestinal pathogenic bacteria greater than those observed by the antibiotic, amoxicillin, when tested against Bacillus cereus and Staphylococcus aureus. Antioxidant and antimicrobial activities of AS extracts seemed to be positively correlated with the present amount of flavonoids. These findings suggest a potential use of AS as a coadjuvant agent for treating bacterial-induced intestinal diseases with high rates of antibiotic resistance

Obtaining bioactive peptides from enzymatic hydrolysis of caseinate and sheep cheese whey

Peptídeos bioativos são foco de pesquisas devido ao interesse relacionado a suas propriedades antioxidantes, anti-hipertensivas, entre outras. Enzimas proteolíticas microbianas aparecem como potentes biocatalisadores para a obtenção de hidrolisados protéicos e peptídeos bioativos em escala industrial/comercial. Neste estudo, hidrolisados de caseinato ovino e soro de queijo ovino foram produzidos utilizando enzimas proteolíticas de Bacillus sp. P7, e as atividades antioxidantes (sequestro de radicais, atividade quelante de ferro e poder redutor), antimicrobiana e anti-hipertensiva (inibição da enzima conversora de angiotensina-I (ECA)) dos hidrolisados foram avaliadas. A atividade antioxidante dos hidrolisados de caseinato ovino, quando avaliada pelo método da captura do radical ácido 2,2’-azinobis-(3-etil-benzotiasolina-6- ácido sulfônico) aumentou com o tempo de hidrólise em até 2 h, mantendo-se estável durante 4 h. Os hidrolisados mostraram baixa capacidade em capturar o radical 2,2-difenil-1-picrilidrazila (DPPH), apresentando maior atividade (31%) após 1 h de hidrólise. A capacidade de quelação de Fe2+ foi máxima em 0,5 h de hidrólise (83,3%), decrescendo em seguida, e o maior poder redutor foi observado após 1h de hidrólise. A inibição da atividade da ECA aumentou até 2h de hidrólise (94% de inibição), diminuindo após esse tempo. Hidrolisados após 3h mostraram inibir a multiplicação de Bacillus cereus, Corynebacterium fimi, Aspergillus fumigatus, e Penicillium expansum. Nos hidrolisados de soro de queijo ovino a proteína solúvel e aminoácidos livres tenderam a aumentar durante o tempo de hidrólise por até 4h. A atividade antioxidante dos hidrolisados avaliados pelo método da captura do radical ácido 2,2’-azinobis-(3- etil-benzotiasolina-6-ácido sulfônico), aumentou de 0h (15,9%) para 6h (51,3%). A máxima quelação de Fe2+ foi observada em hidrolisados após 3h, e o pico do poder redutor em 1h de hidrólise, representando aumentos de 6,2 e 2,1 vezes, respectivamente, quando comparado com o soro de queijo não hidrolisado. A inibição da ECA pelo soro de queijo ovino (12%) aumentou através da hidrólise, alcançando valor máximo (55% inibição) em 4h de hidrólise; no entanto, uma inibição de 42% foi observada após 1h de hidrólise.Bioactive peptides are a focus of research due to the interest related to their antioxidant and antihypertensive properties, among others. Microbial proteolytic enzymes appear as potent biocatalysts to obtain protein hydrolysates and bioactive peptides on an industrial/commercial scale. In this study, ovine cheese whey and ovine caseinate were produced using proteolytic enzymes from Bacillus sp. P7, and the antioxidant (scavenging of the radical, iron-chelating activity, and reducing power), antimicrobial, and antihypertensive (inhibition of the angiotensin-I converting enzyme(ACE)) activities of the hydrolysates were evaluated. Antioxidant activity measured by the 2,2_-azino-bis-(3- ethylbenzothiazoline)-6-sulfonic acid method increased with hydrolysis time up to 2 h, remaining stable for up to 4 h. Hydrolysates showed low 2,2-diphenyl-1- picrylhydrazyl radical scavenging abilities, with higher activity (31%) reached after 1 h of hydrolysis. Fe2+-chelating ability was maximum for 0.5 h hydrolysates (83.3%), decreasing thereafter; and the higher reducing powerwas observed after 1h of hydrolysis. ACE-inhibitory activity was observed to increase up to 2 h of hydrolysis (94% of inhibition), declining afterwards. 3 h hydrolysates were shown to inhibit the growth of Bacillus cereus, Corynebacterium fimi, Aspergillus fumigatus, and Penicillium expansum. Soluble protein and free amino acids tended to increase during hydrolysis of SCW for up to 4 h. Antioxidant activity of hydrolysates, evaluated by the 2,2’azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid radical scavenging method, increased 3.2-fold from 0 h (15.9%) to 6 h of hydrolysis (51.3%). Maximum Fe2+ chelation was reached in 3-h hydrolysates, and the reducing power peaked at 1 h of hydrolysis, representing 6.2- and 2.1-fold increments, respectively, when compared to that of non-hydrolyzed SCW. ACE inhibition by SCW (12%) was improved through hydrolysis, reaching maximal values (55% inhibition) in 4-h hydrolysates; however, a 42% inhibition was already observed after 1 h of hydrolysis

Obtaining bioactive peptides from enzymatic hydrolysis of caseinate and sheep cheese whey

Peptídeos bioativos são foco de pesquisas devido ao interesse relacionado a suas propriedades antioxidantes, anti-hipertensivas, entre outras. Enzimas proteolíticas microbianas aparecem como potentes biocatalisadores para a obtenção de hidrolisados protéicos e peptídeos bioativos em escala industrial/comercial. Neste estudo, hidrolisados de caseinato ovino e soro de queijo ovino foram produzidos utilizando enzimas proteolíticas de Bacillus sp. P7, e as atividades antioxidantes (sequestro de radicais, atividade quelante de ferro e poder redutor), antimicrobiana e anti-hipertensiva (inibição da enzima conversora de angiotensina-I (ECA)) dos hidrolisados foram avaliadas. A atividade antioxidante dos hidrolisados de caseinato ovino, quando avaliada pelo método da captura do radical ácido 2,2’-azinobis-(3-etil-benzotiasolina-6- ácido sulfônico) aumentou com o tempo de hidrólise em até 2 h, mantendo-se estável durante 4 h. Os hidrolisados mostraram baixa capacidade em capturar o radical 2,2-difenil-1-picrilidrazila (DPPH), apresentando maior atividade (31%) após 1 h de hidrólise. A capacidade de quelação de Fe2+ foi máxima em 0,5 h de hidrólise (83,3%), decrescendo em seguida, e o maior poder redutor foi observado após 1h de hidrólise. A inibição da atividade da ECA aumentou até 2h de hidrólise (94% de inibição), diminuindo após esse tempo. Hidrolisados após 3h mostraram inibir a multiplicação de Bacillus cereus, Corynebacterium fimi, Aspergillus fumigatus, e Penicillium expansum. Nos hidrolisados de soro de queijo ovino a proteína solúvel e aminoácidos livres tenderam a aumentar durante o tempo de hidrólise por até 4h. A atividade antioxidante dos hidrolisados avaliados pelo método da captura do radical ácido 2,2’-azinobis-(3- etil-benzotiasolina-6-ácido sulfônico), aumentou de 0h (15,9%) para 6h (51,3%). A máxima quelação de Fe2+ foi observada em hidrolisados após 3h, e o pico do poder redutor em 1h de hidrólise, representando aumentos de 6,2 e 2,1 vezes, respectivamente, quando comparado com o soro de queijo não hidrolisado. A inibição da ECA pelo soro de queijo ovino (12%) aumentou através da hidrólise, alcançando valor máximo (55% inibição) em 4h de hidrólise; no entanto, uma inibição de 42% foi observada após 1h de hidrólise.Bioactive peptides are a focus of research due to the interest related to their antioxidant and antihypertensive properties, among others. Microbial proteolytic enzymes appear as potent biocatalysts to obtain protein hydrolysates and bioactive peptides on an industrial/commercial scale. In this study, ovine cheese whey and ovine caseinate were produced using proteolytic enzymes from Bacillus sp. P7, and the antioxidant (scavenging of the radical, iron-chelating activity, and reducing power), antimicrobial, and antihypertensive (inhibition of the angiotensin-I converting enzyme(ACE)) activities of the hydrolysates were evaluated. Antioxidant activity measured by the 2,2_-azino-bis-(3- ethylbenzothiazoline)-6-sulfonic acid method increased with hydrolysis time up to 2 h, remaining stable for up to 4 h. Hydrolysates showed low 2,2-diphenyl-1- picrylhydrazyl radical scavenging abilities, with higher activity (31%) reached after 1 h of hydrolysis. Fe2+-chelating ability was maximum for 0.5 h hydrolysates (83.3%), decreasing thereafter; and the higher reducing powerwas observed after 1h of hydrolysis. ACE-inhibitory activity was observed to increase up to 2 h of hydrolysis (94% of inhibition), declining afterwards. 3 h hydrolysates were shown to inhibit the growth of Bacillus cereus, Corynebacterium fimi, Aspergillus fumigatus, and Penicillium expansum. Soluble protein and free amino acids tended to increase during hydrolysis of SCW for up to 4 h. Antioxidant activity of hydrolysates, evaluated by the 2,2’azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid radical scavenging method, increased 3.2-fold from 0 h (15.9%) to 6 h of hydrolysis (51.3%). Maximum Fe2+ chelation was reached in 3-h hydrolysates, and the reducing power peaked at 1 h of hydrolysis, representing 6.2- and 2.1-fold increments, respectively, when compared to that of non-hydrolyzed SCW. ACE inhibition by SCW (12%) was improved through hydrolysis, reaching maximal values (55% inhibition) in 4-h hydrolysates; however, a 42% inhibition was already observed after 1 h of hydrolysis