Abstract Microorganisms are the primary responsible for food poisoning and food spoilage. The purpose of this study was to evaluate different fruit washing methods with tap water, electrolyzed water and rhamnolipids solution produced by Pseudomonas aeruginosa LBI, in order to inhibit microbial growth. The tested organism was Eugenia uniflora. The fruits were washed and periodically inoculated into culture media to evaluate and count the colonies on the fruit surface. It was also observed the deterioration level of the fruits after each treatment. The results showed that treatment with rhamnolipids were the most efficient, inhibiting the growth of fungi and bacteria. The electrolyzed water proved to be very efficient in bacterial inhibition at the initial time, but in the final time it did not present any inhibitory effect. The electrolyzed water was also not effective in eliminating fungus. Washing with tap water was the less efficient treatment of all. The only treatment that showed an increased durability has been with rhamnolipids, increasing shelf life by up to two days. Thus rhamnolipids are the most recommended method for fruits sanitation.

O presente trabalho utilizou formas paramorfogênicas de Neurospora crassa 74A linhagens, na remoção do corante "Erythrosin B". O fungo, induzido química e fisicamente em forma de "pellets", foi usado no estudo da biodegradação deste corante. A cultura fúngica foi crescida em meio contendo o corante, como única fonte de carbono por 2 e 90h de interação. As paredes celulares foram isoladas por um processo de lavagem em água destilada e o micélio fresco foi secado por 12 h a 105ºC, e transformado num pó fino, e analisado em FTIR. O sobrenadante foi analisado através de espectrofotômetro UV-VIS e FTIR. Diferenças significativas no espectro UV-VIS e no FTIR foram observadas entre o controle e o sobrenadante e entre o controle e as paredes coloridas de vermelho e em FTIR no tempo de 2 e 90 h. Algumas bandas foram modificadas sugerindo a possibilidade de uma biodegradação enzimática em função do tempo de contato entre o corante e a biomassa fúngica.

The present work used paramorphic forms of Neurospora crassa 74A to remove erythrosine. The fungus culture was grown in medium containing the dye, as only carbon source for 2 and 90 h of interaction. A washing process using distilled water isolated the cellular mass mycelia was dried for 12 h at 105ºC and transformed in fine powder and analyzed in FTIR. The supernatant was analyzed through spectrophotometer UV-Vis and FTIR. Significant differences in the spectrum of UV-VIS and FTIR were observed between the control and the supernatant and between wall control and the walls colored by red, in FTIR for 2 and 90 h. Some significant bands were modified, suggesting the possibility of enzymatic biodegradation in proportion to the time of contact between the dye and fungal biomass.

O solo do pólo cerâmico no município de Santa Gertrudes, SP, tem sido poluído há décadas por diversos elementos químicos, principalmente chumbo e zinco. Foram realizadas quatro coletas de amostras de solo, duas durante a época chuvosa e duas na seca, em cinco locais, de novembro de 2002 a junho de 2003, determinando-se temperatura, pH, teores de chumbo e zinco e a umidade do solo. Os fungos foram isolados pelo método de Warcup, modificado pelo preparo de suspensões aquosas de solo (1:10) e aplicação de 1 cm³ das suspensões sobre malte agar (2%), adicionado de Zn(NO3)2 e Pb(NO3)2 em concentrações crescentes: 0, 100, 200, 500 e 1.000 mg dm-3. Após cinco dias de incubação a 25 ºC, as colônias foram purificadas e identificadas. Foram obtidos 70 táxons de fungos anamorfos, com 70% de similaridade entre as micotas obtidas nos meios com os dois metais. Foram isolados 43 táxons nos meios de cultura com Pb(NO3)2, com predominância deles nas concentrações mais elevadas (500 a 1.000 mg dm-3). Foram obtidos 63 táxons nos meios com Zn(NO3)2, principalmente nas concentrações moderada e elevada (200 e 500 mg dm-3). Prevaleceram espécies de Trichoderma, de Penicillium e diversos fungos que são encontrados associados a substratos vegetais em decomposição. A tendência de se obter número elevado de táxons em meios de cultura com concentrações moderadas a elevadas de Zn e Pb pode ser justificada pela existência de bem adaptada e competitiva micota do solo, caracterizada por elevada capacidade de tolerância aos metais e eficiente habilidade sapróbia competitiva.

The soil of the ceramic pole in the Santa Gertrudes town, São Paulo State, Brazil, has been polluted since decades with several chemical elements, mainly lead and zinc. Four soil samples were collected, two during rainy and two during dry seasons, at five sites during November 2002 to June 2003, and measures of temperature, pH, lead, zinc and moisture soil contents were made. Fungi were obtained by Warcup's soil-plate method, modified by application of 1 cm³ of aqueous soil suspensions (1:10) over malt agar (2%), added with Zn(NO3)2 or Pb(NO3)2 in increasing concentrations: 0, 100, 200, 500 or 1,000 mg dm-3. After five days of incubation at 25 ºC, the colonies were purified and identified. Seventy anamorphic fungi were obtained, with 70% of similarity between mycotas isolated from the media added with metals. Forty-three taxa were isolated from culture media with Pb(NO3)2, with predominance of isolations in higher concentrations (500 and 1,000 mg dm-3). Sixty-three taxa were obtained in the media with Zn(NO3)2, mainly in moderate and high concentrations (200 and 500 mg dm-3). Trichoderma spp., Penicillium spp. and several fungi species usually found in decomposing plant debris prevailed. The tendency to obtain higher numbers of fungal taxa in culture media with moderate to high concentrations of Zn and Pb may be justified by the existence of well adapted and competitive soil mycota, characterized by a high tolerance to metals and an efficient saprobic competitive ability.