Potential for bifenthrin removal using microalgae from a natural source.

The accumulation of environmental pesticides can cause problems in aquatic ecosystems and adverse effects in humans. These compounds can be found in water due to runoff from agricultural, industrial and domestic applications. In Southern Brazil, tobacco cultivation is one of the most important economic agricultural activities. The bifenthrin pesticide, classified as having moderate toxicity (class II), is commonly used as an insecticide in this culture. In this context, the present research aimed to study the performance of microalgae-induced bioremediation processes. Microalgae were isolated from a natural water source in the city of Santa Cruz do Sul, RS, Brazil, which is an artificial reservoir used for public water supply. For this purpose, biodegradation, biosorption, influence of pH, percentage of inoculum and photoperiod were evaluated in batch experiments for 20 cultivation days. After the phycoremediation process, the bifenthrin pesticide (m/z = 181) was quantified by gas chromatography with mass spectrometry (GC-MS). The results indicated that microalgae isolated from the water of the lake were able to contribute to the removal of approximately 99% of bifenthrin through biodegradation and biosorption processes. Photodegradation was identified (>77%) and the best condition for the phycoremediation was 20% inoculum with a photoperiod of 18:6 h.

Bioproducts characterization of residual periphytic biomass produced in an algal turf scrubber (ATS) bioremediation system.

The transformation of residual biomass from bioremediation processes into new products is a worldwide trend driven by economic, environmental and social gain. The present study aimed to evaluate the potential for obtaining bioproducts of technological interest from the remaining periphytic biomass formed during a bioremediation process with an algal turf scrubber (ATS) system installed in a lake catchment. Different methodologies were used according to the target bioproduct. Analyses were performed by high performance liquid chromatography with diode array detector (HPLC/DAD), gas chromatography mass spectrometry (GC-MS), ultraviolet-visible spectroscopy (UV-VIS) and inductively coupled plasma optical emission spectrometry (ICP-OES). The results demonstrated that the periphytic biomass presented potential since protein (17.7%), carbohydrates (22.4%), total lipids (3.3%) with 3.6 mg mL-1 of fatty acids, antioxidants (144.5 µmol Trolox eq. g-1) and chlorophyll a, chlorophyll b and carotenoids (1,719.7 µg mL-1, 541.2 µg mL-1 and 317.7 µg mL-1, respectively) were obtained. Inorganic analysis presented a value of 42.3 ± 2.58% of total ash and metal presence was detected, indicating bioaccumulation. The properties found in periphyton strengthen the possibility of its application in different areas, ensuring bioremediation efficiency.

Current approaches and trends in the production of microbial cellulases using residual lignocellulosic biomass: a bibliometric analysis of the last 10 years.

Considering the potential use of lignocellulosic biomass residues in microbial cultures to produce cellulases, the objective of this research was to investigate trends and discussions regarding scientific research conducted in this field through a bibliometric and scientometric analysis. Using the Elsevier Scopus database and VOSviewer software, scientific papers published between 2007 and 2018 were investigated. The results showed that the production of cellulases is related to obtaining xylanases and glucose. Obtaining of bioethanol and determining cellulolytic and xylanase activities were the relevant indicators for the use of these enzymes. China, India and Brazil are countries with a high number of publications in this field, most likely due to investments made between 2015 and 2017. This analysis showed that research on the use of lignocellulosic residues is focused on obtaining biofuels through enzymatic hydrolysis.

Tobacco waste hydrolysate of stem and root of the tobacco plant for biostimulation in rice and corn seed germination / Hidrolisado de resíduo de caule e raiz da planta tabaco para bioestimulação na germinação de sementes de arroz e milho

ABSTRACT: Stimulation of seed germination may be due to acceleration of germination as well as due to seedling growth-promotion during early development. Plant hydrolysate can be applied as a stimulant. Thus, we aimed to verify the influence of the hydrolysates, obtained by alkaline or acid treatment, from tobacco (Nicotiana tabacum L.) crop residues (root and stem) on the seed germination process. Seed germination was studied with Oryza sativa (rice) and Zea mays (corn). Sixteen germination experiments of 50 seeds each were undertaken, with 4 replicates, soaked with hydrolysates diluted at 20 and 80%, in 2 and 3 mL of hydration volumes for 48 h. Germinated seeds were counted, at which point radicular protrusions were observed. Rootlets and aerial parts were collected, dried and weighed. The hydrolysates presented seedling nutrition potential to the corn, with ~50% more mass compared to the results with water at the same conditions, and the germination acceleration was not significant. For the tested rice seeds, the results were reversed, and the germination acceleration was significant with rates up to 94% after 48 h of incubation. Better results of germination were obtained with hydrolysate from acid treatment, and root or stem tobacco can be used for this purpose.

RESUMO: A estimulação da germinação das sementes pode ser devida à aceleração da germinação, bem como à melhoria do crescimento das mudas durante o desenvolvimento inicial. O hidrolisado de plantas pode ser aplicado como estimulante. Assim, objetivou-se verificar a influência dos hidrolisados, obtidos por tratamento alcalino ou ácido, dos resíduos da cultura do tabaco (Nicotiana tabacum L.) (raiz e caule) no processo de germinação das sementes. A germinação das sementes foi estudada com Oryza sativa (arroz) e Zea mays (milho). Foram realizados dezesseis experimentos de germinação de 50 sementes cada, com 4 repetições, hidratadas em hidrolisados diluídos a 20 e 80%, em 2 e 3 mL de volumes de hidratação por 48 h. As sementes germinadas foram contadas, momento em que foram observadas protrusões radiculares. Radículas e partes aéreas foram coletadas, secas e pesadas. Os hidrolisados apresentaram potencial nutricional de plântulas para o milho, com ~ 50% a mais de massa quando comparados aos resultados com água nas mesmas condições, e a aceleração da germinação não foi significativa. Para as sementes de arroz testadas, os resultados foram contrários e a aceleração da germinação foi significativa com taxas de até 94% após 48 h de incubação. Melhores resultados de germinação foram obtidos com hidrolisado a partir do tratamento ácido, e a raiz ou caule de tabaco pode ser utilizado para esse fim.

Microalgae: cultivation techniques and wastewater phycoremediation.

Generation of liquid and gaseous effluents is associated with almost all anthropogenic activities. The discharge of these effluents into the environment without treatment has reduced the availability and quality of natural resources, representing a serious threat to the balance of different ecosystems and human health. Universal access to water and global warming are topics of intense concern and are listed as priorities in the vast majority of global scientific, social and political guidelines. Conventional techniques to treat liquid and gaseous effluents pose economic and/or environmental limitations that prevent their use in certain applications. The technique of phycoremediation, which uses microalgae, macroalgae, and cyanobacteria for the removal or biotransformation of pollutants, is an emerging technology that has been highlighted due to its economic viability and environmental sustainability. This literature review discusses different techniques of microalgae cultivation and their use in the phycoremediation of contaminants in wastewater.

The occurrence of aflatoxin B1 contamination in peanuts and peanut products marketed in southern Brazil

This study investigated the occurrence of aflatoxin B1 in peanuts and peanut products marketed in the State of Rio Grande do Sul, Brazil. One hundred one samples of peanuts and peanut products were collected and analyzed by thin-layer chromatography with a charge-coupled device system. Aflatoxin B1 was present in 14% of the samples analyzed, in concentrations ranging from 24.0 to 87.5 µg/kg in the peanut samples and from 22.0 to 84.6 µg/kg in the peanut-product samples. These values exceeded the Brazilian regulatory limit (20.0 µg/Kg for aflatoxins B1+G1+B2+G2 ). These results suggest that although aflatoxin contamination in peanuts marketed in southern Brazil is lower than in other Brazilian regions, it is still a serious problem for human health and the economy.

Patulin accumulation in apples during storage by Penicillium expansum and Penicillium griseofulvum strains

A part of apples destined to juice production is generally of poor quality. Apples from cold storage or recently harvest (ground harvested or low quality apples) are stored under ambient conditions until they are processed. Since Penicillium expansum and P. griseofulvum are the principal fungal species isolated from stored apples in Brazil, the objective of this study was to investigate the ability of these strains to produce patulin in apples and report the consequences of this type of storage in loss of quality. The toxin was quantified using thin layer chromatography and charge-coupled device camera (TLC-CCD). The rate and quantities that P. expansum and P. griseofulvum can grow and produce patulin are highly dependent on the fungal strain and time. Lesion diameter resulted to be independent of the strain considered. The maximum period of time which apples were kept at cold storage (4 ºC) without patulin accumulation was 27 days. When these apples were kept at 25 ºC during 3 days, both factors lesion diameter and patulin production increased significantly. These results confirm that time in which apples are taken out from cold storage room before juice production is critical in order to prevent patulin accumulation.

Patulin accumulation in apples during storage by penicillium expansum and penicillium griseofulvum strains.

A part of apples destined to juice production is generally of poor quality. Apples from cold storage or recently harvest (ground harvested or low quality apples) are stored under ambient conditions until they are processed. Since Penicillium expansum and P. griseofulvum are the principal fungal species isolated from stored apples in Brazil, the objective of this study was to investigate the ability of these strains to produce patulin in apples and report the consequences of this type of storage in loss of quality. The toxin was quantified using thin layer chromatography and charge-coupled device camera (TLC-CCD). The rate and quantities that P. expansum and P. griseofulvum can grow and produce patulin are highly dependent on the fungal strain and time. Lesion diameter resulted to be independent of the strain considered. The maximum period of time which apples were kept at cold storage (4 °C) without patulin accumulation was 27 days. When these apples were kept at 25 °C during 3 days, both factors lesion diameter and patulin production increased significantly. These results confirm that time in which apples are taken out from cold storage room before juice production is critical in order to prevent patulin accumulation.

Aspectos relacionados à presença de fungos toxigênicos em uvas e ocratoxina A em vinhos / Aspects related to the presence of toxigenic fungi in grapes and ochratoxin A in wines

A colonização dos Aspergillus da secção Nigri nas uvas durante o cultivo é a principal fonte de ocratoxina A (OTA) nos vinhos. A. carbonarius e A. niger são os principais produtores desta micotoxina em uvas e são fungos oportunistas que, se desenvolvem, principalmente, nas bagas danificadas durante seu amadurecimento. A produção de OTA em uvas é influenciada pelas condições climáticas e áreas geográficas, bem como pela variedade de uva, pelo sistema de cultivo e pelos danos causados nas uvas por insetos, infecção fúngica ou excesso de irrigação e chuva. As medidas para o controle de fungos toxigênicos devem considerar esses pontos críticos de controle. A OTA presente nas uvas é transferida para o vinho durante o processo de vinificação, sendo que um aumento na concentração de OTA ocorre após a maceração das uvas. Durante o envelhecimento do vinho, observa-se que a toxina permanece estável, pois a mesma concentração de OTA é encontrada no vinho após um ano de armazenamento. Boas práticas de produção, como, por exemplo, a seleção e separação dos cachos de uva com desenvolvimento fúngico visível auxilia, consideravelmente, na redução dos níveis de contaminação por fungos produtores de OTA, bem como dos níveis dessa micotoxina nos vinhos.

The infection of grapes by 'black aspergilli' in the field is the main source of ochratoxin A (OTA) in the wine. Aspergillus carbonarius and A. niger fungi are the main producers of this mycotoxin in grapes. They are opportunistic fungi that develop mainly on damaged berries at ripening. The production of OTA in grapes is influenced by climatic conditions, geographical location, grape varieties, crop system, berries damage caused by insets, fungal infection or excessive irrigation and rainfall. Control measures for toxigenic mycoflora in the vineyards must consider these critical control points. OTA in grapes is transferred to wine during vinification and an increase of OTA concentration in must was observed during maceration. The toxin remains stable during wine aging because the same OTA concentration is found in wine after 1 year. Good Agriculture Practices including balanced soil tillage, irrigation, nitrogen fertilization and pruning associated with Good Manufacturing Practices, such as separation of rot bunches helps considerably to reduce OTA-producing fungi and levels of mycotoxin in wine.

Quantitative analysis of patulin in apple juice by thin-layer chromatography using a charge coupled device detector.

A method was developed and validated in-house for the detection and quantification of patulin in apple juice concentrate using a charge coupled device (CCD) on thin-layer chromatography (TLC) plates. Samples were extracted with ethyl acetate and then cleaned-up by extraction with a sodium carbonate solution. The method showed a mean recovery of 95%. The quantification and detection limit were 14 microg l(-1) and 0.005 microg per spot, respectively. The CCD camera is sufficiently sensitive to detect changes in spot fluorescence intensity caused by small differences in mycotoxin concentration under homogeneous illumination from a UV light source. The results of validation confirmed the efficiency of the method, which is sensitive enough to be used to quantify patulin in apple juice by producers or for government monitoring/survey programs. The method was applied to the analysis of 16 apple juice concentrate samples and patulin levels ranged from 15 to 46 microg l(-1). This study demonstrated the applicability of the TLC-CCD technique as a tool for monitoring patulin in apple juice.

Micobiota e micotoxinas em amostras de arroz coletadas durante o sistema estacionário de secagem e armazenamento / Mycobiota and mycotoxins in rice samples collected during the stationary drying and storage system

Considerando as perdas qualitativas e quantitativas no período pós-colheita de grãos, neste trabalho foram avaliadas a contaminação fúngica e as micotoxinas em arroz com casca, durante o sistema estacionário de secagem e armazenamento. As amostras foram coletadas em intervalos de 60 dias durante o armazenamento, em duas alturas do silo-secador. A amostra inicial apresentou 5,4x10(4)UFC g-1, sendo que a contagem aumentou significativamente durante a secagem e o armazenamento, chegando a 10(5)UFC g-1. A contaminação fúngica diferiu no interior do silo-secador, com maior contaminação na porção superior do silo. Os gêneros predominantes foram Aspergillus e Penicillium, com maior ocorrência de A. flavus (26,3 por cento) e P. commune (19,1 por cento). Quatro isolados de A. flavus produziram aflatoxina B1, mas não foram detectadas micotoxinas nas amostras.

Considering the qualitative and quantitative losses in post-harvest of grain, in this research was evaluated fungi and mycotoxins contamination in whole rice (Oryza sativa L.) during the stationary drying and storage system. Samples were collected in a period of sixty days in two heights of the warehouse during storage. The initial sample presented 5.4x10(4)CFU g-1; the contamination increased significantly during drying and storage, up to 10(5)CFU g-1. Fungi contamination was different inside the warehouse with higher contamination in the upper portion. The more abundant fungi genera were Aspergillus and Penicillium, A. flavus (26.3 percent) and P. commune (19.1 percent) which presented higher incidence. Aflatoxin B1 was produced by four A. flavus isolates, but mycotoxins were not detected in the samples.

Ocorrência, aspectos toxicológicos, métodos analíticos e controle da patulina em alimentos: [revisão] / Occurrence, toxicological aspects, analytical methods and control of patulin in food: [review]

A patulina é uma micotoxina produzida por várias espécies de Penicillium, Aspergillus e Byssochlamys. Em experimentos com animais, ela demonstrou ter atividade mutagênica, carcinogênica e teratogênica. Tem sido freqüentemente encontrada em maçãs e derivados. A patulina é facilmente transferida da maçã para o suco durante o processamento devido a sua alta solubilidade em água. Essa micotoxina é muito estável ao aquecimento em meio ácido, como no suco de maçã. Assim, a presença de patulina em suco de maçã é um indicador da qualidade das maçãs utilizadas no processamento. Muitos métodos têm sido desenvolvidos para a determinação da patulina, principalmente baseados na extração líquido-líquido com acetato de etila e determinação por CLAE. É importante evidenciar a necessidade de legislação que regulamente limites dessa micotoxina em alimentos no Brasil. Esta revisão bibliográfica tem como objetivos descrever as principais características da patulina, a ocorrência, os aspectos toxicológicose os métodos desenvolvidos para sua detecção e controle durante os estágios da produção da maçã e suco.

Patulin is a mycotoxin produced by several Penicillium, Aspergillus and Byssochlamys species. Patulin is a highly toxic compound which has shown to be mutagenic, carcinogenic and teratogenic in experiments with animals. It has often been found in apples and apple products. Patulin is easily transfered into apple juice during processing due to its high solubility in water. This mycotoxin is very stable to heat in acidic medium as in apple juice. Thus, patulin content of apple juice is an indicator of the quality of the apples used to juice production. Many methods have been developed for the patulin determination mainly based on liquid-liquid extraction with ethyl acetate and use of HPLC for detection. It is important to show the need of legislation that imposes patulin limits in foods in Brazil. The objectives of this review are to describe the main patulin characteristics, occurrence, toxicological aspects, methods developed for patulin detection and control during the stages of apple and juice production.