Filter Paper Test Research Articles

Toxicity assessment of nano-hydroxyapatite, -zeolite, and -iron tetroxide to soil fauna: The earthworm (Eisenia fetida) as a model organism

The toxicity of nanoparticles has attracted much attention, but the toxicity of nanoparticle types to soil fauna remains unclear. In this study, the earthworm (Eisenia fetida) was selected as a representative soil fauna to evaluate the toxicity of nano-hydroxyapatite (n-HAP), -zeolite (n-zeolite), and -iron tetroxide (n-Fe3O4) to soil fauna. The results showed that the skin ultrastructure, mortality, growth, antioxidant systems, and genetic material of the earthworms were affected to varying degrees by different nanoparticles. A filter paper test indicated that dermal exposure to nanoparticles primarily caused lesions in the cuticle, microvilli, and nucleus of the epithelial cells of earthworm skin. Soil incubation experiments showed that all types of nanoparticles could cause weight loss in earthworms, but only n-Fe3O4 resulted in their death. The reactive oxygen species and glutathione contents in earthworms exposed to n-Fe3O4 were much higher than those in earthworms exposed to n-HAP and n-zeolite. All nanoparticles stimulated the catalase and lactate dehydrogenase activity and damaged the DNA of earthworms. Integrated biomarker responses showed that the toxicity to earthworms increased in the following order: n-HAP < n-zeolite < n-Fe3O4. The characterization results indicated that the differences in surface hydroxyl groups and surface charge may be the cause of the differences in toxicity between n-HAP and n-zeolite with similar properties. The highest toxicity of n-Fe3O4 could be due to the size, spherical morphology, positive surface charge and the presence of Fe(II).

Long-term toxic effects of iron-based metal-organic framework nanopesticides on earthworm-soil microorganism interactions in the soil environment

With the widespread use of controlled-release nanopesticides in field conditions, the interactions between these nanopesticides and biological systems are complex and highly uncertain. The toxicity of iron-based metal organic frameworks (CF@MIL-101-SL) loaded with chlorfenapyr (CF) to terrestrial invertebrate earthworms in filter paper and soil environments and the potential mechanisms of interactions in the nanopesticide-earthworm-cornfield soil microorganism system were investigated for the first time. The results showed that CF@MIL-101-SL was more poisonous to earthworms in the contact filter paper test than suspension concentrate of CF (CF-SC), and conversely, CF@MIL-101-SL was less poisonous to earthworms in the soil test. In the soil environment, the CF@MIL-101-SL treatment reduced oxidative stress and the inhibition of detoxifying enzymes, and reduced tissue and cellular substructural damage in earthworms compared to the CF-SC treatment. Long-term treatment with CF@MIL-101-SL altered the composition and abundance of microbial communities with degradative functions in the earthworm intestine and soil and affected the soil nitrogen cycle by modulating the composition and abundance of nitrifying and denitrifying bacterial communities in the earthworm intestine and soil, confirming that soil microorganisms play an important role in reducing the toxicity of CF@MIL-101-SL to earthworms. In conclusion, this study provides new insights into the ecological risks of nanopesticides to soil organisms.

Pengaruh Air Cucian Beras dan Air Mikroorganisme Lokal Terhadap Mortalitas Rayap Tanah

Subterranean termites (Coptotermes curvignathus) are dangerous termites compared to other types of termites because thay cause damage to crops in plantations and agriculture and have a wide distribution. The use of chemical pesticides causes pests to become resistant and harmful to the environment and health. Botanical pesticides are used as an alternative solution that is environmentally friendly by utilizing leri water and MOL water. This research aims to determine the effect of leri water and lokal microorganism ater (MOL) to control subterranean termites and to determine the optimal formulation as an anti-termite. The research method using 5 formulations of botanical pesticide, namely 100% leri water, 100% MOL water, 50% leri water : 50% MOL water, 75% leri water : 25% MOL water, 25% leri water : 75% MOL water and control (without formulation). Each test container contains 5 soldier termites and 20 worker termites and is given a filter paper test that has been soaked with a predeterminated formulation. Each treatment was replicated 3 times and observed every 24 hours for 72 hours. The results showed that all formulations had no effect on subterranean termite mortality.

Do Commercial Insect Repellents Provide Protection against the Tick Amblyomma sculptum (Acari: Ixodidae)?

Amblyomma sculptum is a species of public health interest because it is associated with the transmission of the bacteria that causes Brazilian Spotted Fever (BSF). The use of repellents on humans is a prophylactic measure widely used to provide protection against a series of arthropod vectors, including mosquitoes and ticks. However, in Brazil, the effectiveness of commercial repellents against A. sculptum is little known. Therefore, it is necessary to carry out specific studies to evaluate the repellency of these commercial products, registered for use against mosquitoes, against the star tick. The main goal of the present work was to evaluate the effectiveness of six commercial repellents against A. sculptum. Unfed nymphs, aged between two and eight weeks, were tested against products based on DEET (OFF!® and Repelex®), Icaridin (Exposis® and SBP®), and IR3535 (Johnsons and Henlau). Three bioassays were conducted to evaluate tick behavior: (i) filter paper, (ii) fingertip, and (iii) field. All bases tested showed high repellent activity, differing significantly (p < 0.05) from the control. It was observed the formulation with DEET resulted in the best results in the filter paper bioassay. In the fingertip bioassay, the DEET base repelled a greater number of ticks compared to Icaridin. In the field bioassay, there was no significant difference between the Icaridin base and DEET, and both formulations differed from the control (p < 0.05). The six formulations tested showed significant percentages of repellency against ticks; however, for the fingertip and field bioassays, the products OFF!®, Repelex®, and Exposis® were tested as they showed better performance in the filter paper test. OFF!® showed the best percentage of repellency (100%), followed by Repelex® (96.8%), and Exposis® (93.1%), considering the two-hour period of the bioassay-field-test. Proving the effectiveness of repellents on the market against A. sculptum presented in this study is crucial, since this is the main ectoparasite of humans that can transmit Rickettsia rickettsii when infected. The effectiveness of commercial insect repellents against other tick species that parasitize humans can also be explored.

Larvicidal activity in vitro of essential oils against Cochliomyia hominivorax

Cochliomyia hominivorax, from the family Calliphoridae, is responsible for causing most myiases in domesticated animals in Brazil. As alternatives to conventional treatments, essential oils (EOs) could possibly be used as natural control of ectoparasites. The aim of this study was to evaluate the in vitro activity of EOs from Salvia sclarea L., Rosmarinus officinalis L., Lavandula hybrida Reverchon, Citrus bergamia Risso, Citrus paradisi L., Juniperus virginiana L., Copaifera reticulata Ducke, Illicium verum Hook f., Pelargonium roseum, Cymbopogon winterianus Jowitt, Cymbopogon flexuosus Steud, Eugenia caryophyllus Spreng, Cinnamomum cassia Presl, Thymus vulgaris L. and Origanum vulgare L. against third-instar larvae of C. hominivorax. To evaluate the mortality rate, filter paper tests were performed at different concentrations and verified after 24 h and 48 h. Essential oils of T. vulgaris, O. vulgare and I. verum induced 100% mortality in the screening test, and their main active components (thymol, carvacrol and anethol, respectively) were also tested alone. In this new test, lethal concentrations (LC50) after 24 h and 48 h, respectively, were 407.1 and 314.2 µg.cm-² for T. vulgaris, 540.9 and 253.8 µg.cm-² for O. vulgare, 314.2 µg.cm-² (after 48 h) for I. verum, 255.6 and 102.3 µg.cm-² for thymol, 970.5 and 931.1 µg.cm−2 for carvacrol and 559.4 µg.cm−2 (after 48 h) for anethol. These results showed the potential of these EOs and their main components for development of ectoparasiticides for veterinary use, especially T. vulgaris EO and thymol.

Estimación de la curva característica suelo agua en suelos arenosos mediante el ensayo de papel filtro

The unsaturated soils mechanics is strongly related to the suction phenomenon that occurs between solid soil particles, which changes when the soil water content does not remain constant. The soil-water characteristic curve (SWCC) provides information related to suction and water content of the soil; and to obtain such a curve different direct and indirect methods can be used. In this research the soil-water characteristic curve for sands is obtained through the implementation of the filter paper test. For this purpose, three reconstituted samples of sandy soils from Lima – Peru (relative density between 20% and 60%) were tested following the wet path of the curve. The samples were stored at least seven days until equilibrium was reached. In this way, discrete points of the soil-water characteristic curve were obtained. SWCC equations such as Brooks and Corey (1964), Van Genuchten (1980), and Fredlund and Xing (1994) were used to adjust the data and obtain their respective parameters for sandy soils. Results show that the filter paper test can be used to obtain the soil-water characteristic curves of reconstituted sandy soils; and that the matric suction of sandy soil can be obtained in seven days period by means of this method; whereas a longer storage time could require to reach the equilibrium and to obtain the total suction for these soils.

Isolasi dan Aktivitas Bakteri Selulolitik pada Limbah Diapers

This study aims to isolate cellulolytic bacteria that have the potential to degrade cellulose by taking home-scale diaper waste samples. This research was also conducted to isolate and determine the ability of bacteria to degrade cellulose based on the Congo red test and filter paper degradation test. This research method is descriptive qualitative. Isolation of cellulolytic bacteria was carried out using selective Carboxymethyl Cellulose (CMC) media. The characterization was carried out by growing selected pure isolates on CMC media and then dropping congored drops to test their cellulolytic potential (cellulolytic potential is indicated by the appearance of a clear zone around the colony). The results showed that the results of isolating bacteria obtained 12 isolates that were able to grow and utilize cellulose as a carbon source. In the Congo red test isolate DS07 cellulolytic bacteria of the Hafnia genus had the highest cellulolytic index value of 2.5 mm. Isolate DS03 with the genus Bacillus had the highest ability to degrade cellulose on the Whatman No. filter paper test. 1 of 16.66%.&#x0D; Keywords: Bacteria, Diapers, Isolation, Cellulolytic

Toxicity, repellency, and anti-cholinesterase activities of bioactive molecules from clove buds Syzygium aromaticum L. as an ecological alternative in the search for control Hyalomma scupense (Acari: Ixodidae)

IntroductionThe goal of the current study is to evaluate the acaricidal and repellent properties of the ethanolic extract, essential oil, and primary component eugenol from Syzygium aromaticum against Hyalomma scupense cattle ticks. Their potential mechanisms of action were also examined, using an in vitro assay. MethodsClove essential oil was extracted using hydrodistillation technique. Gas chromatography-mass spectrometry (GC-MS) was performed to identify the chemical composition of clove. To evaluate the adulticidal, ovicidal, larvicidal and repellent proprieties of clove essential oil, eugenol and ethanolic extract on H. scupense, in vitro assays were performed using the adult immersion test (AIT), the ovicidal test, the larval packet test (LPT), the filter paper test and anti-acetylcholinesterase (AChE) activity. ResultsAfter treatment, eugenol, the primary phytoconstituent of clove oil, which accounts for 97.66% of the whole oil, had 99.22% acaricide activity and inhibited egg hatching at a concentration of 10 mg/mL. Eugenol and clove essential oil showed potent adulticidal effect at high concentrations (10 mg/mL), achieving 100 and 93.76% mortality, respectively. The ethanolic extract exhibited moderate activity. At high concentration, the larvicidal activity of S. aromaticum oil, eugenol, and ethanolic extract were 100, 100, and 77.18%, respectively. In filter paper experiments, when tested at the concentration 5 mg/mL; eugenol showed the longest repellent effect up to 6 h. We also found that eugenol was the most active AChE inhibitor (IC50 = 0.178 mg/mL). Nevertheless, additional investigations are required to confirm the accurate mechanism and the relevance of clove in practical application. ConclusionOverall, our research indicated that, because its effectiveness as acaricide, S. aromaticum essential oil and its phytoconstituent eugenol may offer an alternative source for the control of H. scupense cattle ticks.

The thioacetal-modified phenothiazine as a novel colorimetric and fluorescent chemosensor for mercury in aqueous media

A new probe, called PTE, has been developed for detecting Hg2+ using a phenothiazine (PTE) unit with a dithioacetal group as the response unit. The synthesis of PTE was conducted initially, followed by studying its interactions with a variety of ions using UV–Vis and fluorescence spectroscopy in real water samples. Based on the UV–Vis and fluorescence studies, it was discovered that PTE exhibited turn-on sensor properties against Hg2+ ions. Additionally, the LOD value for PTE/Hg2+ was determined to be 102 nM. Moreover, the study also examined the visual color changes of PTE on filter paper and TLC test strips. The results indicated that PTE can be effectively used in mercury-containing solutions, as it produces fast color and spectroscopic changes.

Evaluation of Thermal and Rheological Properties of Phase Change Material-Incorporated Asphalt Mastic with Porous Fillers

Incorporating phase change material (PCM) into paving materials can regulate the pavement temperature, improve the pavement durability, and mitigate the heat-island effects. In this research, porous fillers were used as the PCM carrier, and the thermal and rheological behaviors of the asphalt mastic with the PCM were evaluated. Two different carrier materials (diatomite and expanded perlite) and four types of PCMs were used in the study. The candidate filler, PCM, and proper blending ratios were determined based on the results of scanning electron microscope image analysis, the filter paper test, and the temperature sweep test. The thermal and rheological behaviors of the mastics with PCMs were further evaluated with different filler replacement ratios. Thermal analysis through a differential scanning calorimetry test, thermal conductivity and volumetric heat capacity test, and real-time temperature performance test were performed on the asphalt mastics. Rheological tests, including the complex shear modulus test, the bending beam rheometer test, and the linear amplitude sweep test, were also conducted. The modified mastics were found to have high heat capacity with the latent heat storage ability. The rheological analyses showed that with the addition of polyethylene glycol, while the low-temperature performance of the asphalt mastics was improved, the performance at intermediate and high temperatures was not adversely affected by the PCM.

Screening for Pompe Disease in High-Risk Pediatric Patients: Experience from a Tertiary Care Center in Rajasthan

AbstractA high index of suspicion is required to diagnose rare genetic disorders, such as Pompe disease, with common clinical manifestations in children. There is a need to sensitize physicians regarding cues to early screening and diagnosis of such patients. Minimal epidemiological data are available on Pompe disease in India. The aim of this study was to determine the prevalence of Pompe disease in high-risk pediatric populations and determine the appropriateness of screening dried blood spot (DBS) tests to facilitate the diagnosis of Pompe disease. We screened pediatric patients presented with (1) unexplained hypotonia, respiratory distress, cardiomyopathy, and elevated liver function tests; and (2) unexplained limb girdle muscle weakness through a DBS test for enzyme assay. Those patients found positive underwent acid alpha-glucosidase mutational analysis. This prospective cross-sectional study was conducted in 45 suspected patients after approval from the institutional ethical committee. Of the 45 suspected patients, 9 (20%) were found to be positive by DBS test. Out of these nine tested, four (44.4%) were positive, two (22.2%) were negative, and three (33.3%) could not be tested for mutation analysis. The prevalence of genetically confirmed Pompe disease in high-risk populations was 8.8%. The results of this study show that clinical suspicion and DBS filter paper test facilitate early diagnosis and management, thereby improving the quality of life in patients. DBS test acts as a robust, rapid first-tier screening test for Pompe disease.

A method to study the effects of combined stress of cadmium and microplastics on the acute toxicity of Eisenia fetida.

The compound pollutants formed by microplastics and cadmium present a significant potential threat to the soil-based ecosystem, and it is urgent to carry out relevant ecotoxicological studies. However, the lack of appropriate test methods and scientific mathematical analysis models has restricted the progress of research. Based on an orthogonal test design, a ternary combined stress test was performed to study the effect of microplastics and cadmium on earthworms. This study used the particle size and concentration of microplastics as well as the concentration of cadmium as test factors. Using the improved factor analysis model and the TOPSIS (Technique for Order Preference by Similarity to Ideal Solution) method, a new model was constructed according to the response surface methodology to analyze the acute toxic effects on earthworms under the combined stress of microplastics and cadmium. In addition, the model was tested in a soil-polluted environment. The results show that the model can perfectly integrate the spatiotemporal cross effects of the concentration and time of the applied stress, and the scientific data analysis process ensures the efficient development of ecotoxicological research in the actual compound pollution environment. Moreover, the results of the filter paper test and soil test showed that the equivalent toxicity ratio of cadmium concentration, microplastic concentration, and microplastic particle size to earthworms as 26:35:39 and 23:36:41, respectively. In terms of the interaction effect, a certain positive interaction was observed between the cadmium concentration and that of the microplastics and their particle size, while a negative interaction was observed between the concentration of microplastics and their particle size. This research provides a test basis and model reference for early monitoring of the health of contaminated soils and assessments of ecological safety and security.

Assessment of the acute toxicity of agrochemicals on earthworm (Aporrectodea caliginosa) using filter paper contact and soil mixing tests

Abstract. El-Aswad AF, Fouad MR, Aly MI. 2023. Assessment of the acute toxicity of agrochemicals on earthworm (Aporrectodea caliginosa) using filter paper contact and soil mixing tests. Asian J Agric 7: 14-19. Earthworms are suitable bioindicators of chemical contamination in terrestrial ecosystems. Therefore, adult earthworms (Aporrectodea caliginosa Savigny, 1826), which are common in Egyptian rice fields were used to study the side effects of fenitrothion and thiobencarb. Also, it was used two common Egyptian soil types; alluvial soil (clay soil) and the calcareous soil (sandy clay loam soil). Two tests were used; filter paper contact test at 24, 48 and 72 h, and the soil mixing test at 5 and 10 days. The effect of both pesticides on mortality of earthworm was insignificant at 24 h with a low mortality percentage. LC50 value of fenitrothion and thiobencarb were 83.16, 288.26, 24.67, and 39.98 µg a.i mL-1 at 48 and 72 h, respectively. Based on the LC50 values, fenitrothion was 3.5 and 1.6 times more toxic than thiobencarb at 48 and 72 h, respectively. At 5 and 10 days after treatment, respectively, the LC50 for fenitrothion in the soil mixing test decreased from 334.27 to 55.45 in clay soil and from (415.90) to (25.00) in sandy soil. Regarding to fenitrothion in soil mixing test, the LC50 was reduced from 334.27 to 55.45 in clay soil and from 415.90 to 25.00 in sandy soil at 5 and 10 days after treatment, respectively. Also, the LC50 of thiobencarb in clay soil was decreased from 0.93 to 0.41 and from 55.28 to 10.65 at 5 and 10 days, respectively. In general, a positive relation was recorded between the tested pesticide toxicity on earthworm and concentrations, and also exposure time. Fenitrothion was more toxic on earthworm in contact filter paper test than thiobencarb. While, in clay soil, fenitrothion was least toxic to the earthworm in soil mixing test, this could be attributed to the slow degradation in the worms and subsequently less elimination of the metabolites as well as attributed to its higher adsorption and lower desorption in soil.

Selection of chemical pesticide to minimize toxic effect to ladybird beetle Coccinella septempunctata Linn (Coleoptera: Coccinellidae) while managing black bean aphid Aphis fabae Scop. (Hemiptera: Aphididae)

Faba bean (Vica faba L.) is important crop of Nepal which is grown in all climatic zone of country. Different insect pests are host of faba bean but black bean aphid Aphis fabae Scop. (Hemiptera: Aphididae) is of more concern. Most of the farmer shifted to another crop due to A. fabae problem. Different insecticide have been sprayed to manage this aphid but most of the farmer were unable control them. However, very limited research were conducted for its ecofriendly management. Thus, we evaluate different insecticides such as nitenpyram, flonicamid, imidacloprid, dimethoate, azadirachtin, and neem oil on laboratory. Scintillating glass vial test and filter paper test were employed. Higher number of aphid mortality were found on dimethoate with LT50 value of 15.93 hour followed by nitenpyram, and imidacloprid with 18.61 and 32.87 hour, respectively on scintillating glass vial test. On filter paper test, LT50 of dimethoate was 27.34 hour followed by imidacloprid and nitenpyram with 49.51 and 53.44, respectively. Similarly, higher lady bird beetle Coccinella septempunctata Linn (Coleoptera: Coccinellidae) mortality were also caused by dimethoate with LT50 value of 63.38 hour followed by imidacloprid and nitenpyram with 153.21 188.42 hour. Our result suggested that nitenpyram or imidacloprid could be used for ecofriendly management of A. fabae with low mortality of its predator C. septempunctata. However precautionary measure has to be taken before applying them and waiting period has to be maintained for harvesting.

Effect of Imidacloprid and Chloropyrifos Toxicity on Earthworm Amynthas alexandri Under Laboratory Conditions

Aim: To highlight the impact of commonly used insecticides on earthworms as they represent the largest fraction of soil biomass. Earthworms were exposed to different concentrations of insecticides using a contact filter paper test method. Materials and Methods: Acute toxicity was tested for 48 hr using a filter paper contact toxicity test (Whatman filter paper no.1). After 48 hexposure, morphological changes and DNA Damage were observed and the treated earthworms were fixed with 10% (w/v) for 24 h in formalin solution for the histological test. Results: Based on Median lethal concentration, the insecticides applied at the field recommended dose in the study are classified as super toxic in the contact filter toxicity test. The highest mortality was caused by Imidacloprid and found to be the most toxic. Conclusion: Insecticides even when used at field recommended doses cause lethal effects on various activities of earthworms including DNA damage and reduced reproductive potential leading to a poor density of earthworms including poor soil fertility. The altered morphological and histological changes were also observed when earthworms get direct or indirect exposure to insecticides. Therefore, it is important to standardize and rationalize the use of pesticides simultaneously a higher degree of awareness and education as needed at all levels including the vendors and producers of pesticides.

Insecticidal activity of essential oil of Cannabis sativa against the immature and adult stages of Ctenocephalides felis felis.

Essential oil (EO) of Cannabis sativa (C. sativa) was evaluated against the egg, larval, pupal, and adult stages of the flea Ctenocephalides felis felis. The chemical composition of EO was determined by gas chromatography with flame ionization and mass spectrometry. EO mainly comprised γ-elemene (16.2%) and caryophyllene oxide (14.2%) as major compounds. To evaluate the mortality of flea stages in vitro, filter paper tests were performed at different concentrations. EO of C. sativa showed insecticidal activity (100% mortality at the highest concentrations) for flea control at egg, larval, pupal, and adult stages, with lethal concentrations (LC50) of 32.45; 91.61; 466.41 and 927.92 μg/cm2, respectively. EO of C. sativa indicated the potential for the development of ectoparasiticide for veterinary use, especially for fleas in egg and larval stages.

Cyanide selective colorimetric and turn-on fluorimetric sensing by naphthohydrazide derivative and its application in real sample analysis

Synthesis, characterization of (E)-3-hydroxy-N'-(2-hydroxy-3-methoxybenzylidene)-2-naphthol hydrazide (HNV) and its sensing ofCN− ion have been described in this paper. Probe HNV is formed by the reaction of o-vanillin and 3-hydroxy-2-naphthoic acid hydrazide and is confirmed by FT-IR, 1H NMR and ESI-MS spectrometry. Addition of CN− ion in probe HNV results in the establishment of a new absorption band at 400 nm in UV–visible spectrum and turn-on fluorescent behavior in H2O-DMSO (7:3 v/v) mixed solvent. Fluorescence intensity of probe HNV is found to be enhanced by 13.1 times in presence of CN−. Colorless solution of HNV is converted to yellow on addition of CN− ion and similar change in color is noticed on Whatman filter paper test strips also. Binding mechanism for the probe HNV with CN− is validated using 1H NMR titration. HNV can be applied for the analysis of real water samples..

Pesticide residue exposure provides different responses of the microbiomes of distinct cultures of the stored product pest mite Acarus siro

BackgroundThe contribution of the microbiome to pesticide breakdown in agricultural pests remains unclear. We analyzed the effect of pirimiphos-methyl (PM) on four geographically different cultures of the stored product pest mite Acarus siro (6 L, 6Tu, 6Tk and 6Z) under laboratory experiments. The effect of PM on mite mortality in the impregnated filter paper test was compared.ResultsThe mite sensitivity to PM decreased in the order of 6 L, 6Tu, 6Tk, and 6Z. Then, the mites were cultured on PM residues (0.0125 and 1.25 µg·g−1), and population growth was compared to the control after 21 days of exposure. The comparison showed two situations: (i) increasing population growth for the most sensitive cultures (6 L and 6Tu), and (ii) no effect on mite population growth for tolerant cultures (6Z and 6Tk). The microbiome of mites was analyzed by quantification of 16S DNA copies based on quantitative polymerase chain reaction (qPCR) and by barcode sequencing of the V4 fragment of 16S DNA on samples of 30 individuals from the control and PM residues. The microbiome comprised primarily Solitalea-like organisms in all cultures, except for 6Z, followed by Bacillus, Staphylococcus, and Lactobacillus. The microbiomes of mite cultures did not change with increasing population density. The microbiome of cultures without any differences in population density showed differences in the microbiome composition. A Sodalis-like symbiont replaced Solitalea in the 1.25 µg·g−1 PM in the 6Tk culture. Sodalis and Bacillus prevailed in the microbiomes of PM-treated mites of 6Z culture, while Solitalea was almost absent.ConclusionThe results showed that the microbiome of A. siro differs in composition and in response to PM residues in the diet. The results indicate that Sodalis-like symbionts can help recover mites from pesticide-induced stress.

Bithiophene-benzothiazole fluorescent sensor for detecting hypochlorite in water, bio-fluids and bioimaging in living cells, plants and zebrafish

Rationally designed and effectively synthesized D-π-A chemosensor DTA containing bithiophene fluorophore by using bithiophene aldehyde and benzothiazole salt and serves as highly specific chemosensor for colorimetric/fluorimetric turn-on detection of hypochlorite (ClO−) in ∼100 % aqueous media. DTA has obvious advantages of high specificity, short response time (8 s), broad pH working scope, ultra-sensitivity with low detection limit (5.3 nM), good bio-compatibility and permeability. The responding mechanism of DTA toward ClO− was investigated by 1H NMR, FTIR, HRMS, optical spectra and DFT calculations. Interestingly, DTA coated silica-gel, cotton buds, and filter-paper test strips were developed for qualitative and quantitative visual detection of ClO− in real-time. Notably, DTA was utilized to quantitatively detect ClO− in real-water and bio-fluids. Moreover, DTA was also applied to bioimage ClO− in live-cells, zebrafish and plant kingdoms, highlighting its broad application potentials. The simple structure and versatility of the DTA provides a convenient approach for developing multi-functional sensors and expanding its broader application fields.

Toxicity comparison of atrazine on Eisenia fetida in artificial soil and three natural soils

Atrazine has been widely used in the world and caused environmental pollution, especially soil pollution. When assessing the toxicity of atrazine in soil, most studies used standardized artificial soils, while few studies focused on the real soil environments. In the present study, three natural soils and artificial soil were selected as test soils to study and compare the toxicities of atrazine to Eisenia fetida. Acute toxicity of atrazine was determined by filter paper and soil tests. In chronic toxicity study, after atrazine exposure, the content of reactive oxygen species in Eisenia fetida significantly increased and showed a dose-response relationship. The activity changes of three antioxidant enzymes and glutathione transferase showed that atrazine had obvious oxidative stress effect on earthworms. The contents of malondialdehyde and 8-hydroxy deoxyguanosine in 0.1 and 1 mg/kg atrazine treatment groups were significantly higher than the control, indicating that medium and high concentrations of atrazine could cause lipid and DNA damage in Eisenia fetida. The acute toxicity results and the integrated biomarker response index for chronic toxicity indicated that the toxicity order of atrazine was: red clay > fluvo-aquic soil > artificial soil > black soil, and that the toxicity of atrazine in artificial soil was not representative of its toxicity in real soil environment. The results of correlation analysis showed that three soil property parameters of organic carbon, organic matter and sand were most related to the toxicity of atrazine.