Antimicrobial and antioxidant activities of secondary metabolites from endophytic fungus Botryosphaeria fabicerciana (MGN23-3) associated to Morus nigra L.

This study was to evaluate the biological activity of the extract of Botryosphaeria fabicerciana isolated from leaves of Morus nigra. The volatile compounds from the crude extract were analysed by GC-MS which demonstrate that mellein and ß-orcinaldehyde were are the major compounds. The best minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract was observed against Gram-positive bacteria, with a MIC of 15.6 µg/mL towards B. cereus and MIC of 62.5 µg/mL towards S. aureus and B. subtilis. MBC values of 31.25 µg/mL, 62.5 µg/mL, and 250 µg/mL were observed towards B. cereus, B. subtilis, and S. aureus, respectively. The cytotoxicity analyses showed CC50 of 115 µg/mL. The crude extract showed antioxidant activity by the DPPH, ABTS, and FRAP assays. Therefore, the extract of the endophytic fungus presented biotechnological potential as an antibacterial and antioxidant agent.

Metabolic extract of the endophytic fungus Flavodon flavus isolated from Justicia brandegeana in the control of Alicyclobacillus acidoterrestris in commercial orange juice.

In this work, the antibacterial activity of a crude extract of the endophytic fungus Flavodon flavus (JB257), isolated from leaves of Justicia brandegeana, was evaluated against both the vegetative and sporulated forms of Alicyclobacillus acidoterrestris. The microdilution technique was performed in order to determine the antibacterial activity of the crude extract alone as well as in combination with the bacteriocin, nisin. The minimum inhibitory concentration (MIC) of the crude extract and nisin alone against A. acidoterrestris vegetative forms were 250 µg/mL and 31.5 µg/mL, respectively, while the minimum bactericidal concentrations (MBC) were 1000 µg/mL and 62.5 µg/mL,respectively. For A. acidoterrestris spores, treatment with the crude extract at a concentration of 500 µg/mL caused a 47% reduction in growth, while nisin at 62.5 µg/mL could reduce 100% of the growth. The in vitro evaluation of the crude extract combined with nisin against A. acidoterrestris by the Checkerboard method showed a synergistic interaction between the two compounds. In addition, greater selectivity towards bacterial cells over host cells, a human hepatocyte cell line, was achieved when the crude extract was combined with nisin, Using scanning electron microscopy, interferences in the cell membrane of A. acidoterrestris could be observed after treatment with the crude extract. The results presented in this study indicate that the crude extract of the endophyte F. flavus has biotechnological potential in the food industry, especially for the treatment of orange juices through the control of A. acidoterrestris.

Evaluation of cytotoxicity and mutagenicity of the benzodiazepine flunitrazepam in vitro and in vivo

Flunitrazepam (FNZ) is a sedative benzodiazepine prescribed for the short-term treatment of insomnia. However, there are concerns regarding possible carcinogenic or genotoxic effects of this medicine. Thus, the aim of this study was to evaluate the cytotoxic, clastogenic and aneugenic effects of FNZ in hepatoma cells from Rattus norvegicus (HTC) in vitro and in bone marrow cells of Wistar rats in vivo. These effects were examined in vitro following treatment with 0.2, 1.0, 5.0 or 10 μg/mL FNZ using a micronucleus test with a cytokinesis block or in vivo using a chromosomal aberration test following treatment with 7, 15 or 30 μg/mL/kg body weight. The results showed that the benzodiazepine concentrations tested were not cytotoxic, aneugenic or clastogenic. However, considering the adverse effects of using this benzodiazepine, more studies are required.

Flunitrazepam (FNZ) é um sedativo benzodiazepínico prescrito para o tratamento da insônia em curto prazo. Entretanto, existe a preocupação com relação aos possíveis efeitos carcinogênicos ou genotóxicos causados por este fármaco. Então, o objetivo deste estudo foi avaliar os efeitos citotóxicos, clastogênicos e aneugênicos do FNZ em células de hepatoma de Rattus norvegicus (HTC) in vitro e em células de medula óssea de ratos Wistar in vivo. Foram testadas as concentrações de 0,2, 1,0 e 10 μg/mL de FNZ pelo teste do micronúcleo com bloqueio de citocinese in vitro e 7, 15 e 30 μg/mL/kg de peso corpóreo para o teste de aberração cromossômica in vivo. Os resultados mostraram que as concentrações do benzodiazepínico testadas não foram citotóxicas, aneugênicas ou clastogênicas. Entretanto, considerando os efeitos adversos do uso deste benzodiazepínico, mais estudos são necessários.

Cytotoxicity and mutagenicity of cola and grape flavored soft drinks in bone marrow cells of rodents / Citotoxicidade e mutagenicidade de refrigerantes sabor cola e uva, em células de medula óssea de roedor

Due to the large consumption of soft drinks in Brazil and worldwide in recent years and considering that some of the components presentin their composition pose potential risks to human health, the aim of this study was to evaluate the cytotoxic and mutagenic potential ofspecific cola and grape-flavored soft drink brands. Bone marrow cells of Wistar rats were initially treated by gavage with one single dose of Cola or Grape soft drink, which was next offered ad libitum (instead of water) for 24 hours. A negative control treatment was performed by administering one single dose of water and a positive control administering cyclophosphamide intraperitoneally. Statistical analysis showedthat the Cola and Grape soft drinks studied were not cytotoxic. However, the Cola soft drink proved mutagenic in this experiment treatmenttime. Therefore, this study serves as a warning about the consumption of Cola-flavored soft drink and for the need for further subchronicand chronic studies on soft drinks in order to evaluate the long term mutagenic and cytotoxic effects of these substances.

Devido ao grande consumo de refrigerantes no Brasil e no mundo nos últimos anos, e tendo em vista que alguns dos componentes presentes na composição destes possuem potenciais danosos para os organismos, em especial o humano, o objetivo deste trabalho foi avaliar o potencial citotóxico e mutagênico de uma marca de refrigerante sabor Cola e uma de sabor Uva. Foram utilizadas como sistema-teste as células demedula óssea de ratos Wistar, tratados via gavagem com dose única do refrigerante sabor Cola ou Uva e, em seguida, fornecidos ad libitum(no lugar da água), por 24 horas. Foi feito um controle negativo, administrando água, em dose única, e um controle positivo administrando ciclofosfamida, via intraperitoneal. A análise estatística mostrou que os refrigerantes sabor Cola e Uva não foram citotóxicos. Entretanto, o refrigerante sabor Cola foi mutagênico neste sistema-teste e tempo de tratamento. Desta forma, este estudo serve de alerta para o consumo de refrigerantes sabor Cola e indica que estudos subcrônicos e crônicos com os refrigerantes devem ser realizados, a fim avaliar os efeitos mutagênicos e citotóxicos dessas substâncias a longo prazo.