Abstract A fibrinolytic enzyme from the microalga Dunaliella tertiolecta was produced under mixotrophic conditions using different corn steep liquor (CSL) concentrations ( 0 ≤ CLS ≤ 0.75%), purified using a combination of salting out and ion-exchange chromatography, and then biochemical characterized. Cultivation of this microalga using 0.5% CSL led to the highest maximum cell concentration (1.960±0.010 mg L-1) and cell productivity (0.140g L-1 day-1), besides a high fibrinolytic activity of the extract obtained by the homogenization method (102 ±1 U mL-1). The enzyme extracted from the microalgal biomass was 5-fold purified with a 20% yield and was found to have a specific activity of 670 U mg-1. The enzyme, whose molecular weight determined by fibrin zymography was 10 kDa, was shown to be stable at pH 3.0–9.0 and up to 70°C with optimal pH and temperature values of 8.0 and 50°C, respectively. When compared to other fibrinolytic enzymes, this protease stood out for its high fibrinolytic activity, which was enhanced by Fe2+, inhibited by Zn2+, Cu2+, Mg2+, and Ca2+, and strongly inhibited by phenylmethylsulfonyl fluoride, suggesting that it belongs to the serine metalloprotease family. Moreover, thanks to its thermal stability, the enzyme may be easily preserved and activated under high-temperature conditions.

Abstract Hypertension is a factor that contributes to the risk of chronic diseases. The inhibition of angiotensin-I converting enzyme (ACE) is a useful therapeutic approach to the hypertension treatment. The algae have been an alternative for the production of ACE inhibitory (ACEi) peptides from enzymatic hydrolysis due to their protein-rich biomass. The aim of this study was to systematically review the literature regarding the production, composition and activity of ACEi peptides derived from algae proteins. Systematic database searches identified 648 related articles. Among these, only 14 were selected according to the eligibility criteria to this review. Macroalgae are more studied than microalgae as sources of ACEi peptides. Furthermore, hydrolysates by thermolysin or bromelain exhibited the highest ACEi activity compared to other enzymes. The main features of the peptides with high ACE inhibition are low molecular weight, short amino acids sequence and non-competitive inhibition pattern. In vivo studies using hydrolysates and peptides derived from algae proteins showed antihypertensive activity in spontaneously hypertensive rats (SHR). Thus, it is suggested that ACEi peptides derived from algae can be considered as potential antihypertensive.

RESUMO: O Câncer de cólon é um dos tipos mais comuns de câncer no mundo e a segunda principal causa de morte relacionada a esta doença em países desenvolvidos. Até 75% dos casos estão associados com a alimentação, indicando que uma pessoa pode reduzir o seu risco simplesmente através de modificação na dieta. Estudos em animais demonstram que várias cepas de bactérias ácido lácticas protegem contra o câncer de cólon em roedores, embora os dados em humanos sejam limitados e conflitantes. O objetivo deste estudo foi investigar a eficácia das bactérias ácido lácticas no tratamento e redução do câncer de cólon em modelo animal. Foram realizadas buscas sistemáticas em bases de dados eletrônicas alcançando 1079 artigos relacionados, entretanto apenas 6 artigos foram eleitos de acordo com os critérios de elegibilidade para análise. Todos os artigos avaliados apresentaram resultados satisfatórios quanto à inibição do câncer de cólon em ratos e camundongos ao utilizarem cepas predominantemente do gênero Lactobacillus. Este estudo pode responder a hipótese de que as bactérias ácido lácticas apresentam efeito preventivo e antitumoral contra o câncer de cólon.

ABSTRACT: Colon cancer is one of the most common types of cancer in the world and the second leading cause of death related to the disease in developed countries. Up to 75% of cases are associated with eating, indicating that a person can reduce their risk simply through dietary modification. Studies in animals show that various strains of lactic acid bacteria protect against colon cancer in rodents although data in humans are limited and conflicting. The aim of this study was to investigate the efficacy of acid lactic bacteria in the treatment and reduction of colon cancer in animal models. Systematic searches were conducted in electronic databases reaching 1079 related articles, only six articles were elected according instead of to the eligibility criteria for analysis. All reviewed articles showed satisfactory results on the inhibition of colon cancer in rats and mice when using predominantly Lactobacillus strains. This study can answer hypothesis that acid lactic bacteria has antitumor effect against colon cancer.

Background Streptomyces sp. DPUA 1576 from Amazon lichens was studied to protease and fibrinolytic production. A 2² factorial experimental design was applied to optimize its protease enzyme production using two independent variables, namely soybean flour and glucose concentrations. Results The optimal conditions to obtain high protease production (83.42 U/mL) were 1.26% soybean flour and 1.23% glucose concentration. A polynomial model was fitted to correlate the relationship between the two variables and protease activity. In relation to fibrinolytic activity, the highest activity of 706.5 mm² was obtained at 1.7% soybean flour and 1.0% glucose concentration, which was 33% higher than plasmin. Fibrinolytic production was not optimized in the studied conditions. Conclusions These results show that the optimization of the culture medium can enhance protease production, thus becoming a good process for further research. In addition, Streptomyces sp. DPUA 1576, isolated from Amazon lichens, might be a potential strain for fibrinolytic protease production.