Diversity of Endophytic and Epiphytic Bacteria From Sugarcane in Khuzestan, Iran

Abstract Diverse microorganisms are living as endophytes in plant tissues and as epiphytes on plant surfaces in nature. Commercial formulations of bacteria antagonist to plant pathogenic microbes and ice nucleation active bacteria have been utilized as an environmentally safe method to manage plant disease and to prevent frost damage respectively. Bacteria were isolated from the leaf and sheath of sugarcane (CP69-1026 CP57-614, CP48-103, CP73-21, and CP70-1143 cultivars) verities grown in the field in Khuzestan province, Iran. Bacteria were found in both sheaths and leaves of sugarcane plants which they were significantly higher in density in leaves and which most were endophytic. The bacterial strains were 10 groups on the basis of the biochemical characteristic, which their 16S rRNA encoding gene from representatives were amplified and subjected to sequencing. Results of sequences analyze using blast software from the NCBI website and phylogenetic analysis showed that the representative strains belonged to a wide variety of phylogenetic groups. These results indicated that they were closely related to Burkholderia and Ralstonia from β-Proteobacteria, Mesorhizobium, Ochrobactrum, Sphingomonas from α-Proteobacteria, Microbacterium, Curtobacterium and Leifsonia from Actinobacteria and Xanthomonas from γ-Proteobacteria. This is the first report of the presence of endophytic and epiphytic bacteria from sugarcane in Khuzestan, Iran.

Carotenoid production in sugarcane juice and synthetic media supplemented with nutrients by Rhodotorula rubra l02

ABSTRACT In order for the use of biological carotenoids to become feasible, it is necessary to have adequate low cost sources and improved methods of cultivation. The aim of this study was to evaluate the effect of supplementation with nitrogen, phosphorus, zinc, and magnesium, on the biomass and carotenoid volumetric production by yeast Rhodotorula rubra L02 using a complex medium (sugarcane juice) and synthetic media (sucrose and maltose) as substrates. The experimental design used for each substrate was randomized in blocks with 16 treatments and 3 repetitions. The treatments were compound for 15 different combinations of nutrients (N; Mg; Zn; P, N + Mg; N + Zn; N + P; Mg + Zn; Mg + P; Zn + P; N + P + Zn; N + P + Mg; N + Zn + Mg; P + Zn + Mg; N + Zn + Mg + P) alone and combined, and a control. The results were submitted to analysis of variance and Tukey test at 5% significance level. Among the treatments evaluated, the highest production of dry biomass, with both maltose and sucrose, was observed for Mg (1.60 g/L and 1.94 g/L, respectively). Additionally, another treatment that stood out in terms of biomass production was the control treatment with maltose (1.54 g/L). After the incubation time, killer activity was not observed since there was no formation of inhibition halo around the L02 yeast.

Draft genome sequence of Paraburkholderia tropica Ppe8 strain, a sugarcane endophytic diazotrophic bacterium

Abstract Paraburkholderia tropica (syn Burkholderia tropica) are nitrogen-fixing bacteria commonly found in sugarcane. The Paraburkholderia tropica strain Ppe8 is part of the sugarcane inoculant consortium that has a beneficial effect on yield. Here, we report a draft genome sequence of this strain elucidating the mechanisms involved in its interaction mainly with Poaceae. A genome size of approximately 8.75 Mb containing 7844 protein coding genes distributed in 526 subsystems was de novo assembled with ABySS and annotated by RAST. Genes related to the nitrogen fixation process, the secretion systems (I, II, III, IV, and VI), and related to a variety of metabolic traits, such as metabolism of carbohydrates, amino acids, vitamins, and proteins, were detected, suggesting a broad metabolic capacity and possible adaptation to plant association.

Avaliação microbiológica do caldo de cana comercializado por ambulantes e estabelecimentos formais em Salvador, BA / Microbiological evaluation of cane juice marketed by street vendors and formal establishments in Salvador, BA

[{"text": "O objetivo desse estudo foi avaliar a qualidade microbiológica do caldo\r\nde cana comercializado por ambulantes e estabelecimentos formais em\r\nSalvador-Bahia e comparar com padrões sanitários vigentes na legislação.\r\nTrata-se de um estudo transversal, onde foram realizadas análises microbiológicas\r\npara determinação de coliformes totais, termotolerantes, Salmonella\r\nspp, e bolores e leveduras, e das condições higienicossanitárias dos locais de\r\ncomercialização do produto por meio da aplicação de uma lista de checagem.\r\nOs resultados obtidos foram comparados com os padrões sanitários determinados\r\npela legislação brasileira onde, tanto os estabelecimentos formais\r\nquanto os informais, apresentaram um nível considerável de contaminação,\r\ncom apenas uma amostra satisfatória. Pode-se verificar que o caldo de cana\r\nofertado, tanto pelo setor formal quanto pelo informal, estava impróprio para\r\nconsumo, pois a análise microbiológica mostrou que a maioria das amostras\r\napresentavam contaminação acima do limite aceitável da legislação, além da\r\npresença de micro-organismos indicadores de qualidade higienicassanitária\r\ninsatisfatória.(AU)", "_i": "pt"}]

Condições microbiológicas e higienicossanitárias do caldo de cana comercializado no município de Curitiba- PR / Microbiological and hygienic sanitary conditions of saccharum juice marketed in the city of Curitiba, PR

O caldo de cana é uma bebida popular e amplamente comercializada por ambulantes em diversas cidades brasileiras. Esse tipo de comércio deve cumprir as boas práticas determinadas pela legislação, uma vez que pode propiciar as Doenças Transmitidas por Alimentos (DTA) pela venda de bebidas contaminadas. O objetivo deste trabalho foi avaliar as condições higienicossanitárias e microbiológicas da produção de caldo de cana no município de Curitiba em 10 pontos de venda. O estudo foi dividido em duas etapas: avaliação de cinco parâmetros relativos às condições estruturais e dos manipuladores, por meio de um roteiro de inspeção; e avaliação da qualidade microbiológica do caldo de cana, por meio da coleta de duas amostras em cada ponto de venda. Foi observado que 60% dos comerciantes manipulavam dinheiro simultaneamente ao preparo do caldo e não utilizavam luvas. Além disso, em 40% havia a presença de insetos, 30% apresentavam estrutura precária e 10% dos manipuladores não usavam cabelos presos. Dos locais avaliados, 60% tiveram amostras classificadas como impróprias para o consumo, sendo observados valores superiores a 2 Log.NMP/mL de coliformes termotolerantes, em que todas estavam contaminadas por E. coli. Por fim, a melhoria no cumprimento das boas práticas relaciona-se com a qualidade microbiológica. De acordo com os resultados obtidos no presente estudo, foi visto que se faz necessária a implementação de medidas para a capacitação deste grupo de comerciantes sobre as boas práticas e constante atuação de vigilância de seu cumprimento, preservando a saúde da população no sentido de prevenir as DTA.(AU)

Sugarcane trash levels in soil affects the fungi but not bacteria in a short-term field experiment

Abstract The sugarcane in Brazil is passing through a management transition that is leading to the abolition of pre-harvest burning. Without burning, large amounts of sugarcane trash is generated, and there is a discussion regarding the utilization of this biomass in the industry versus keeping it in the field to improve soil quality. To study the effects of the trash removal on soil quality, we established an experimental sugarcane plantation with different levels of trash over the soil (0%, 50% and 100% of the original trash deposition) and analyzed the structure of the bacterial and fungal community as the bioindicators of impacts. The soil DNA was extracted, and the microbial community was screened by denaturing gradient gel electrophoresis in two different seasons. Our results suggest that there are no effects from the different levels of trash on the soil chemistry and soil bacterial community. However, the fungal community was significantly impacted, and after twelve months, the community presented different structures among the treatments.

Sugarcane straw as a feedstock for xylitol production by Candida guilliermondii FTI 20037

Abstract Sugarcane straw has become an available lignocellulosic biomass since the progressive introduction of the non-burning harvest in Brazil. Besides keeping this biomass in the field, it can be used as a feedstock in thermochemical or biochemical conversion processes. This makes feasible its incorporation in a biorefinery, whose economic profitability could be supported by integrated production of low-value biofuels and high-value chemicals, e.g., xylitol, which has important industrial and clinical applications. Herein, biotechnological production of xylitol is presented as a possible route for the valorization of sugarcane straw and its incorporation in a biorefinery. Nutritional supplementation of the sugarcane straw hemicellulosic hydrolyzate as a function of initial oxygen availability was studied in batch fermentation of Candida guilliermondii FTI 20037. The nutritional supplementation conditions evaluated were: no supplementation; supplementation with (NH4)2SO4, and full supplementation with (NH4)2SO4, rice bran extract and CaCl2·2H2O. Experiments were performed at pH 5.5, 30 °C, 200 rpm, for 48 h in 125 mL Erlenmeyer flasks containing either 25 or 50 mL of medium in order to vary initial oxygen availability. Without supplementation, complete consumption of glucose and partial consumption of xylose were observed. In this condition the maximum xylitol yield (0.67 g g-1) was obtained under reduced initial oxygen availability. Nutritional supplementation increased xylose consumption and xylitol production by up to 200% and 240%, respectively. The maximum xylitol volumetric productivity (0.34 g L-1 h-1) was reached at full supplementation and increased initial oxygen availability. The results demonstrated a combined effect of nutritional supplementation and initial oxygen availability on xylitol production from sugarcane straw hemicellulosic hydrolyzate.

Avaliação higienicossanitária do caldo de cana comercializado em lanchonetes na cidade de Sobral: CE

O caldo de cana ou garapa é muito apreciado por ser refrescante e de alto valor energético. O objetivo deste trabalho foi quantificar, pelo método do número mais provável (NMP) e contagem padrão em placas, os coliformes totais e termotolerantes do caldo de cana comercializado em lanchonetes no município de Sobral-CE e, utilizando um roteiro de observação, avaliar as condições sanitárias dos estabelecimentos. Foram analisadas 9 amostras de caldo de cana, nos meses de julho e agosto de 2012, adquiridas em lanchonetes na cidade de Sobral-CE. Das 9 amostras estudadas, em 3 (33,33%) constatou-se a presença de coliformes termotolerantes acima do número permitido pela RDC nº 12. Verificou-se que várias recomendações da RDC (Resolução da Diretoria Colegiada) na 218 não eram obedecidas: em 100% (n=3) das lanchonetes a cana-de-açúcar era armazenada sem nenhuma proteção; 78% (n=7) dos manipuladores apresentavam vestimentas sujas e mal conservadas; 55% (n=S) dos manipuladores manuseavam concomitantemente alimento e dinheiro sem nenhuma assepsia. Observa-se que um dos principais fatores de contaminação refere-se à conduta dos manipuladores.

The juice or syrup is very refreshing and appreciated for being high energy. The aim of this study was to quantify the method most probable number (MPN) and standard plate count, total coliforms and thermotolerant sugarcane juice sold in cafeterias in Sobral-CE and using an observation guide to assess the health conditions of the establishments. We analyzed nine samples of sugarcane juice, in July and August 2012, acquired in cafeterias in the city of Sobral-CE. Of the nine samples studied, 3 (33.33%) showed the presence of fecal coliform above the number allowed by RDC No. 12. It was found that several recommendations of the DRC (Board Resolution) No. 218 were not met: 100% (n = 3) snack sugar cane was stored without protection, 78% (n = 7) of the handlers had clothes dirty and poorly maintained, 55% (n = 5) of food handlers manuseavam concurrently and money without any aseptic. It is observed that one of the main factors of contamination refers to the conduct of handlers.

Thermotolerant and mesophylic fungi from sugarcane bagasse and their prospection for biomass-degrading enzyme production

Nineteen fungi and seven yeast strains were isolated from sugarcane bagasse piles from an alcohol plant located at Brazilian Cerrado and identified up to species level on the basis of the gene sequencing of 5.8S-ITS and 26S ribosomal DNA regions. Four species were identified: Kluyveromyces marxianus, Aspergillus niger, Aspergillus sydowii and Aspergillus fumigatus, and the isolates were screened for the production of key enzymes in the saccharification of lignocellulosic material. Among them, three strains were selected as good producers of hemicellulolitic enzymes: A. niger (SBCM3), A. sydowii (SBCM7) and A. fumigatus (SBC4). The best β-xylosidase producer was A. niger SBCM3 strain. This crude enzyme presented optimal activity at pH 3.5 and 55 °C (141 U/g). For β-glucosidase and xylanase the best producer was A. fumigatus SBC4 strain, whose enzymes presented maximum activity at 60 °C and pH 3.5 (54 U/g) and 4.0 (573 U/g), respectively. All these crude enzymes presented stability around pH 3.0–8.0 and up to 60 °C, which can be very useful in industrial processes that work at high temperatures and low pHs. These enzymes also exhibited moderate tolerance to ethanol and the sugars glucose and xylose. These similar characteristics among these fungal crude enzymes suggest that they can be used synergistically in cocktails in future studies of biomass conversion with potential application in several biotechnological sectors.

Caracterización morfológica y molecular de aislados de Macrophomina phaseolina asociados a caña de azúcar en México / Morphological and molecular characterization of isolates of Macrophomina phaseolina associated with sugarcane in Mexico

La pudrición carbonosa, causada por Macrophomina phaseolina, es una enfermedad importante de la caña de azúcar en México. Este estudio se realizó con el objetivo de caracterizar aislados de M. phaseolina obtenidos de caña de azúcar mediante análisis morfológicos y moleculares. La caracterización morfológica de 10 aislados se llevó a cabo con el uso de microscopia electrónica de barrido y microscopia de luz. Para confirmar la identificación, se extrajo el ADNr de 2 aislados representativos, y la región del espaciador interno transcrito (ITS) se amplificó mediante la reacción en cadena de la polimerasa y se secuenció usando los iniciadores específicos MpKF1 y MpKR1. Los aislados se identificaron como M. phaseolina con base en la morfología. El análisis de secuencias ITS mostró 100% de similitud con las secuencias de M. phaseolina depositadas en el GenBank. Para nuestro conocimiento, este es el primer estudio del mundo enfocado a caracterizar aislados de M. phaseolina obtenidos de caña de azúcar

Charcoal rot caused by Macrophomina phaseolina is an important disease of sugarcane in Mexico. This study was carried out to characterize isolates of M. phaseolina obtained from sugarcane by the combination of morphological and molecular analyses. The morphological characterization of 10 isolates was performed using scanning electron microscopy and light microscopy. To confirm the morphological identification, rDNA from two representative isolates was extracted, and the internal transcribed spacer (ITS) region was amplified by polymerase chain reaction and sequenced using specific primers MpKF1 and MpKR1. Based on their morphological characteristics, all isolates were identified as M. phaseolina. Moreover, the analysis of two ITS sequences showed 100% similarity with the M. phaseolina sequences deposited in the GenBank. To our knowledge, this is the first study in the world aimed at characterizing isolates of M. phaseolina obtained from sugarcane

Early changes in arbuscular mycorrhiza development in sugarcane under two harvest management systems

Sugarcane (Saccharum spp.) is grown on over 8 million ha in Brazil and is used to produce ethanol and sugar. Some sugarcane fields are burned to facilitate harvesting, which can affect the soil microbial community. However, whether sugarcane pre-harvest burning affects the community of arbuscular mycorrhizal fungi (AMF) and symbioses development is not known. In this study, we investigated the early impacts of harvest management on AMF spore communities and root colonization in three sugarcane varieties, under two harvest management systems (no-burning and pre-harvest burning). Soil and root samples were collected in the field after the first harvest of sugarcane varieties SP813250, SP801842, and RB72454, and AMF species were identified based on spore morphology. Diversity indices were determined based on spore populations and root colonization determined as an indicator of symbioses development. Based on the diversity indices, spore number and species occurrence in soil, no significant differences were observed among the AMF communities, regardless of harvest management type, sugarcane variety or interactions between harvest management type and sugarcane variety. However, mycorrhiza development was stimulated in sugarcane under the no-burning management system. Our data suggest that the sugarcane harvest management system may cause early changes in arbuscular mycorrhiza development.

Diversity of 16S rRNA genes from bacteria of sugarcane rhizosphere soil

Sugarcane is an important agricultural product of Brazil, with a total production of more than 500 million tons. Knowledge of the bacterial community associated with agricultural crops and the soil status is a decisive step towards understanding how microorganisms influence crop productivity. However, most studies aim to isolate endophytic or rhizosphere bacteria associated with the plant by culture-dependent approaches. Culture-independent approaches allow a more comprehensive view of entire bacterial communities in the environment. In the present study, we have used this approach to assess the bacterial community in the rhizosphere soil of sugarcane at different times and under different nitrogen fertilization conditions. At the high taxonomic level, few differences between samples were observed, with the phylum Proteobacteria (29.6 percent) predominating, followed by Acidobacteria (23.4 percent), Bacteroidetes (12.1 percent), Firmicutes (10.2 percent), and Actinobacteria (5.6 percent). The exception was the Verrucomicrobia phylum whose prevalence in N-fertilized soils was approximately 0.7 percent and increased to 5.2 percent in the non-fertilized soil, suggesting that this group may be an indicator of nitrogen availability in soils. However, at low taxonomic levels a higher diversity was found associated with plants receiving nitrogen fertilizer. Bacillus was the most predominant genus, accounting for 19.7 percent of all genera observed. Classically reported nitrogen-fixing and/or plant growth-promoting bacterial genera, such as Azospirillum, Rhizobium, Mesorhizobium, Bradyrhizobium, and Burkholderia were also found although at a lower prevalence.

Condições higiênico-sanitárias do caldo de cana comercializado em Teixeira de Freitas, BA / Hygienic-sanitary condition of sugar cane juice sold in Teixeira de Freitas, BA

Este trabalho teve como objetivo geral avaliar a qualidade microbiológica do caldo de cana e as condições higiênico-sanitárias dos manipuladores e equipamentos utilizados para a extração do caldo da cana-de-açúcar comercializado no município de Teixeira de Freitas-BA...