Antifungal activity and inhibition of aflatoxins production by Zingiber officinale Roscoe essential oil against Aspergillus flavus in stored maize grains / Atividade antifúngica e inibição da produção de aflatoxinas pelo óleo essencial de Zingiber officinale Roscoe contra Aspergillus flavus em grãos de milho armazenados

Essential oils are possible alternatives to the use of synthetic pesticides for control of fungal contamination. Ginger (Zingiber officinale) essential oil (GEO) is known for having antifungal and antiaflatoxigenic properties, but its use as a fumigant in situ has not been studied yet. The aim of this study was to evaluate GEOs effects upon Aspergillus flavus as a fumigant agent in stored maize grains. The main compounds reported in GEO were -zingiberene (23.85%) and geranial (14.16%), characterized by gas chromatography-mass spectrometry and nuclear magnetic resonance. The GEO was used as a fumigant in irradiated maize grains in concentrations ranging from 5 to 50 µg/g and the resulting effects were compared to a synthetic antifungal agent (carbendazim and thiram), an antifungal traditionally used for seed treatment. The antifungal efficacy of GEO against A. flavus has been proven in a dose-dependent manner through in situ (maize grains) test. The GEO inhibited aflatoxin production at concentrations 25 and 50 µg/g and controlled fungal growth. Therefore, GEO can be used as an effective and non-toxic alternative to conventional treatments in stored maize grains for the natural control of A. flavus.(AU)

Os óleos essenciais são possíveis alternativas ao uso de praguicidas sintéticos no controle da contaminação por fungos. O óleo essencial de gengibre (Zingiber officinale - OEG) é conhecido por possuir propriedades antifúngicas e antiaflatoxigênicas, mas seu uso como fumigante in situ ainda não foi estudado. O objetivo deste estudo foi avaliar os efeitos do OEG sobre Aspergillus flavus como agente fumigante em grãos de milho armazenados. Os principais compostos encontrados no OEG foram -zingibereno (23,85%) e geranial (14,16%), caracterizados por cromatografia gasosa acoplada a espectrometria de massas e ressonância magnética nuclear. O OEG foi utilizado como fumigante em grãos de milho irradiados em concentrações variando de 5 a 50 µg/g e os efeitos resultantes foram comparados a um agente antifúngico sintético (carbendazim e tiram), antifúngico tradicionalmente usado para o tratamento de sementes. A eficácia antifúngica do OEG contra A. flavus foi comprovada de maneira dependente da dose através do teste in situ (grãos de milho). O OEG inibiu a produção de aflatoxina nas concentrações 25 e 50 µg/g e controlou o crescimento de fungos. Portanto, o OEG pode ser usado como uma alternativa eficaz e não tóxica aos tratamentos convencionais em grãos de milho armazenados para o controle natural de A. flavus.(AU)

Benefits of superfine grinding method on antioxidant and antifungal characteristic of Brazilian green propolis extract

Green propolis is found only in Brazil and due to its important biological characteristics, the food industry views it as a rich source of bioactive compounds. However, an extract must be produced for its application, which is difficult considering the rigid characteristics of raw propolis. Superfine grinding, a process capable of reducing particle size, enables the extraction of most bioactive compounds in propolis. This study evaluated the influence of grinding on size characteristics, antioxidant and antifungal properties of Brazilian green propolis for food preservation. The propolis powder was produced through six different types of grinding (different sieves and rpm), and its quality was evaluated by scanning electron microscopy-energy dispersive X-ray spectroscopy. After grinding, extracts and bioactive assays were produced and the total phenolic content, antioxidant and antifungal capacity were determined. The data showed that the grinding process affected all the results of bioactive assays used. Treatment B (sieve 0.08 mm, 12,000 rpm) presented statistically significant values for the bioactivity assays and thus antifungal activity against Rhizopus stolonifer (doses 0-5 %) was tested only for the control (standardized size without superfine grinding) and treatment B. Both treatments showed antifungal activity, but the control provided more effective mycelial growth inhibition (lower dose 1 %). Superfine grinding increased the antioxidant activity, although this behavior was not observed in the antifungal assay. Despite these results, green propolis extracts present important biological effects that indicate their use as food preservatives to extend shelf life of food products.

Benefits of superfine grinding method on antioxidant and antifungal characteristic of Brazilian green propolis extract

Green propolis is found only in Brazil and due to its important biological characteristics, the food industry views it as a rich source of bioactive compounds. However, an extract must be produced for its application, which is difficult considering the rigid characteristics of raw propolis. Superfine grinding, a process capable of reducing particle size, enables the extraction of most bioactive compounds in propolis. This study evaluated the influence of grinding on size characteristics, antioxidant and antifungal properties of Brazilian green propolis for food preservation. The propolis powder was produced through six different types of grinding (different sieves and rpm), and its quality was evaluated by scanning electron microscopy-energy dispersive X-ray spectroscopy. After grinding, extracts and bioactive assays were produced and the total phenolic content, antioxidant and antifungal capacity were determined. The data showed that the grinding process affected all the results of bioactive assays used. Treatment B (sieve 0.08 mm, 12,000 rpm) presented statistically significant values for the bioactivity assays and thus antifungal activity against Rhizopus stolonifer (doses 0-5 %) was tested only for the control (standardized size without superfine grinding) and treatment B. Both treatments showed antifungal activity, but the control provided more effective mycelial growth inhibition (lower dose 1 %). Superfine grinding increased the antioxidant activity, although this behavior was not observed in the antifungal assay. Despite these results, green propolis extracts present important biological effects that indicate their use as food preservatives to extend shelf life of food products.(AU)

Effect of essential oils on the physiological and sanitary quality of maize seed (Zea mays) / Efeito do tratamento com óleos essenciais sobre a qualidade fisiológica e sanitária das sementes de milho (Zea mays)

The development of pesticides is a constant in the agricultural sector in order to offer products less aggressive to the environment and new active ingredients, preventing the emergence of resistance. The alternative study to fungicides used for seed treatment has the essential oils field for prospecting. This research aimed to evaluate the effects of essential oils from leaves of C. citriodora and E. camaldulensis in maize seed variety AL Bandeirante, from different locations. The physiological and sanitary quality of the seeds were evaluated when treated samples using the oils individually, equal mixture of these oils and treatment with a commercial antifungal. It was observed that the treatment with the oils C. citriodora, E. camaldulensis and the mixture of oils did not affect the immediate germination of seeds Avare. In the batch Bernardino de Campos, treatment with C. citriodora was harmful and E. camualdulensis, although not statistically differ from the others, decreased germination which would prevent its use as seed, according to the standard regulated by the Ministry of Agriculture, Livestock and Supply  (MAPA), 85%. The E.  camaldulensis oil showed phytotoxic effect decreasing the length of seedlings, acetone used as a solvent had no effect on germination but showed phytotoxic effect after accelerated aging. The application of oils alone was able to reduce the incidence of fungi of the genus Penicillium and Fusarium, Aspergillus but the behavior was similar to commercial antifungal, showing no effect when compared to the control treatment.

O desenvolvimento de pesticidas é uma constante no setor agropecuário, visando oferecer produtos menos agressivos ao meio ambiente e novos princípios ativos, evitando o aparecimento de resistência. O estudo de alternativas aos fungicidas utilizados no tratamento de sementes tem nos óleos essenciais um campo para prospecção. Esta pesquisa teve como objetivo avaliar os efeitos dos óleos essenciais provenientes de folhas de C. citriodora e E. camaldulensis, em sementes de milho da variedade AL Bandeirante, de diferentes localidades. A qualidade fisiológica e sanitária das sementes foi avaliada quando se trataram as amostras utilizando os óleos individualmente, a mistura equitativa desses óleos e o tratamento com um antifúngico comercial. Foi observado que o tratamento com os óleos C. citriodora e E. camaldulensis e a mistura dos óleos não afetou a germinação imediata das sementes de Avaré. No lote de Bernardino de Campos, o tratamento com C. citriodora foi prejudicial; com o E. camualdulensis, apesar de não diferenciar estatisticamente dos demais, diminuiu a germinação, o que impediria sua utilização como semente, segundo o padrão normatizado (de 85%) pelo Ministério da Agricultura, Pecuária e Abastecimento (MAPA). O óleo de E. camaldulensis apresentou efeito fitotóxico, diminuindo o comprimento das plântulas; a acetona utilizada como solvente não influenciou sobre a germinação, mas apresentou efeito fitotóxico após o envelhecimento acelerado. A aplicação dos óleos isoladamente foi capaz de diminuir a incidência dos fungos dos gêneros Penicillium e Fusarium, mas para Aspergillus o comportamento foi semelhante ao antifúngico comercial, não apresentando efeito quando comparado ao tratamento testemunha.

Efeito do tratamento com óleos essenciais sobre a qualidade fisiológica e sanitária das sementes de milho (Zea mays) / Effect of essential oils on the physiological and sanitary quality of maize seed (Zea mays)

O desenvolvimento de pesticidas é uma constante no setor agropecuário, visando oferecer produtos menos agressivos ao meio ambiente e novos princípios ativos, evitando o aparecimento de resistência. O estudo de alternativas aos fungicidas utilizados no tratamento de sementes tem nos óleos essenciais um campo para prospecção. Esta pesquisa teve como objetivo avaliar os efeitos dos óleos essenciais provenientes de folhas de C. citriodora e E. camaldulensis , em sementes de milho da variedade AL Bandeirante, de diferentes localidades. A qualidade fisiológica e sanitária das sementes foi avaliada quando se trataram as amostras utilizando os óleos individualmente, a mistura equitativa desses óleos e o tratamento com um antifúngico comercial. Foi observado que o tratamento com os óleos C. citriodora e E. camaldulensis e a mistura dos óleos não afetou a germinação imediata das sementes de Avaré. No lote de Bernardino de Campos, o tratamento com C. citriodora foi prejudicial; com o E. camualdulensis , apesar de não diferenciar estatisticamente dos demais, diminuiu a germinação, o que impediria sua utilização como semente, segundo o padrão normatizado (de 85%) pelo Ministério da Agricultura, Pecuária e Abastecimento (MAPA). O óleo de E. camaldulensis apresentou efeito fitotóxico, diminuindo o comprimento das plântulas; a acetona utilizada como solvente não influenciou sobre a germinação, mas apresentou efeito fitotóxico após o envelhecimento acelerado. A aplicação dos óleos isoladamente foi capaz de diminuir a incidência dos fungos dos gêneros Penicillium e Fusarium , mas para Aspergillus o comportamento foi semelhante ao antifúngico comercial, não apresentando efeito quando comparado ao tratamento testemunha.(AU)

The development of pesticides is a constant in the agricultural sector in order to offer products less aggressive to the environment and new active ingredients, preventing the emergence of resistance. The alternative study to fungicides used for seed treatment has the essential oils field for prospecting. This research aimed to evaluate the effects of essential oils from leaves of C. citriodora and E. camaldulensis in maize seed variety AL Bandeirante, from different locations. The physiological and sanitary quality of the seeds were evaluated when treated samples using the oils individually, equal mixture of these oils and treatment with a commercial antifungal. It was observed that the treatment with the oils C. citriodora , E. camaldulensis and the mixture of oils did not affect the immediate germination of seeds Avare. In the batch Bernardino de Campos, treatment with C. citriodora was harmful and E. camualdulensis , although not statistically differ from the others, decreased germination which would prevent its use as seed, according to the standard regulated by the Ministry of Agriculture, Livestock and Supply (MAPA), 85%. The E. camaldulensis oil showed phytotoxic effect decreasing the length of seedlings, acetone used as a solvent had no effect on germination but showed phytotoxic effect after accelerated aging. The application of oils alone was able to reduce the incidence of fungi of the genus Penicillium and Fusarium, Aspergillus but the behavior was similar to commercial antifungal, showing no effect when compared to the control treatment.(AU)

Effect of essential oils on the physiological and sanitary quality of maize seed (Zea mays) / Efeito do tratamento com óleos essenciais sobre a qualidade fisiológica e sanitária das sementes de milho (Zea mays)

The development of pesticides is a constant in the agricultural sector in order to offer products less aggressive to the environment and new active ingredients, preventing the emergence of resistance. The alternative study to fungicides used for seed treatment has the essential oils field for prospecting. This research aimed to evaluate the effects of essential oils from leaves of C. citriodora and E. camaldulensis in maize seed variety AL Bandeirante, from different locations. The physiological and sanitary quality of the seeds were evaluated when treated samples using the oils individually, equal mixture of these oils and treatment with a commercial antifungal. It was observed that the treatment with the oils C. citriodora, E. camaldulensis and the mixture of oils did not affect the immediate germination of seeds Avare. In the batch Bernardino de Campos, treatment with C. citriodora was harmful and E. camualdulensis, although not statistically differ from the others, decreased germination which would prevent its use as seed, according to the standard regulated by the Ministry of Agriculture, Livestock and Supply  (MAPA), 85%. The E.  camaldulensis oil showed phytotoxic effect decreasing the length of seedlings, acetone used as a solvent had no effect on germination but showed phytotoxic effect after accelerated aging. The application of oils alone was able to reduce the incidence of fungi of the genus Penicillium and Fusarium, Aspergillus but the behavior was similar to commercial antifungal, showing no effect when compared to the control treatment.(AU)

O desenvolvimento de pesticidas é uma constante no setor agropecuário, visando oferecer produtos menos agressivos ao meio ambiente e novos princípios ativos, evitando o aparecimento de resistência. O estudo de alternativas aos fungicidas utilizados no tratamento de sementes tem nos óleos essenciais um campo para prospecção. Esta pesquisa teve como objetivo avaliar os efeitos dos óleos essenciais provenientes de folhas de C. citriodora e E. camaldulensis, em sementes de milho da variedade AL Bandeirante, de diferentes localidades. A qualidade fisiológica e sanitária das sementes foi avaliada quando se trataram as amostras utilizando os óleos individualmente, a mistura equitativa desses óleos e o tratamento com um antifúngico comercial. Foi observado que o tratamento com os óleos C. citriodora e E. camaldulensis e a mistura dos óleos não afetou a germinação imediata das sementes de Avaré. No lote de Bernardino de Campos, o tratamento com C. citriodora foi prejudicial; com o E. camualdulensis, apesar de não diferenciar estatisticamente dos demais, diminuiu a germinação, o que impediria sua utilização como semente, segundo o padrão normatizado (de 85%) pelo Ministério da Agricultura, Pecuária e Abastecimento (MAPA). O óleo de E. camaldulensis apresentou efeito fitotóxico, diminuindo o comprimento das plântulas; a acetona utilizada como solvente não influenciou sobre a germinação, mas apresentou efeito fitotóxico após o envelhecimento acelerado. A aplicação dos óleos isoladamente foi capaz de diminuir a incidência dos fungos dos gêneros Penicillium e Fusarium, mas para Aspergillus o comportamento foi semelhante ao antifúngico comercial, não apresentando efeito quando comparado ao tratamento testemunha.(AU)