Control Of Plant Pathogenic Fungi Research Articles

A nanoscale γ-cyclodextrin metal-organic framework loaded with eugenol (CMFE) for controlling F. graminearum on the wheat during harvest time

The loss of grains in the production chain caused huge waste worldwide, and the control of plant pathogenic fungi during harvest time is a critical solution to mitigate the damage. Eugenol, an important component of clove oil (Syzygium aromaticum L.), has antioxidant, antifungal, and other activities. In this study, the unstable eugenol was incorporated into the nanoscale γ-cyclodextrin metal-organic framework (γ-CD-MOF), a cubic porous structure synthesized by vapor diffusion method. The investigation of morphologies, functional groups, crystalline structures and weight losing behaviors demonstrated the inclusion complex prepared from γ-CD-MOF and eugenol (CMFE). Compared with the γ-CD loaded with eugenol (CE), CMFE exhibited an improved loading rate with 4.06 % (w/w). And CMFE enhanced the stability of its inner eugenol against degradation by light and air. Moreover, the CMFE demonstrated a significant anti-F. graminearum activity both in the medium and on the wheat grains. The inhibition rate reached 83.8 % at 8 mg/mL in vitro, while the growth of the hyphae was effectively restrained at 4 mg/g in vivo. CMFE could damage the mycelial cell wall and trigger intracellular reactive oxygen species (ROS) accumulation, thus exhibiting its anti-F. graminearum activity. Our results showed that the biocompatible CMFE would be an environment-friendly substitute to chemical fungicides for the prevention of fungal contamination caused by F. graminearum.

NanoBioProtectors: Role of plant derived magnetic nanoparticles as a potent biocontrol agent against Fusarium oxysporum ciceris

In the current scenario, where demand for food production is constantly increasing with the rise in population, the threat of plant pathogens has also increased. The destruction of crops due to diseases caused by plant pathogens has become difficult to control with conventional physical and chemical methods. Traditional agriculture often depends on use of chemical pesticides, which have had negative impacts on both living organisms and ecosystems. As a fundamental principle of sustainable agriculture, it is important to limit the use of chemical pesticides in order to safeguard the environment and preserve diverse species. Additionally, sustainable agriculture should operate as a low input system, characterised by reduced production costs and increased net returns. Here, nanotechnology stands as a new weapon against rising challenges in agriculture. Nanotechnology may greatly improve the effectiveness of agricultural inputs, making it a valuable tool for promoting sustainable growth in agroecosystems via the use of nanoparticles. Using magnetic nanoparticles for controlling plant pathogenic fungi can be developed as a potent method for disease management in plants. In the present study, the effect of plant (Carica papaya) -based Fe3O4 magnetic nanoparticles was synthesized and studied against Fusarium oxysporum f.sp. ciceris, a chickpea pathogen. The antifungal effect of these nanoparticles and their minimum inhibitory concentration were studied using a soft agar assay and broth assay. Plant-synthesized nanoparticles were able to inhibit Fusarium oxysporum f.sp. ciceris by up to 87 %. It’s in vivo effect was checked with pot trials on chickpeas. Fe3O4 magnetic nanoparticles have shown adequate inhibition of fungus both in vitro and in vivo.

Proteomics for depicting the secreted protein patterns of Lactiplantibacillus plantarum strains isolated from different food matrices

Lactiplantibacillus plantarum (formerly known as Lactobacillus plantarum), a bacterial species isolated from a wide variety of ecological niches, plays an important role in food industries, being used as a starter culture of food fermentations and contributing to improve flavor, texture, sensorial qualities, and shelf life. It also improves the nutritional and functional properties of fermented foods through the biosynthesis of bioactive compounds and several strains exhibit probiotic features. In recent years, this bacterial species has also shown great potential for controlling plant pathogenic fungi. Shotgun proteomic approach and label free quantitative analyses were used to realize a detailed catalog of the proteins secreted by five L. plantarum strains isolated from vegetable foods or dairy products and exhibiting specific function features. In particular, these strains showed in vitro inhibitory activity against bacteria and molds. Results led to identify 602 proteins differently present in the secretome of the analyzed strains. For instance, proteins of application interest such as bacteriocins, glucansucrase, glycoside hydrolase and chitin binding proteins were differentially secreted in the five strains.The information gathered in this study is a valuable contribution to increasing knowledge in relation to one of the most important bacterial species used as probiotic, for biocontrol of plant pathogenic bacteria and fungi and in different food production worldwide.

Active substances of myxobacteria against plant diseases and their action mechanisms.

Myxobacteria have a complex life cycle and unique social behavior, and obtain nutrients by preying on bacteria and fungi in soil. Chitinase, β-1,3 glucanase and β-1,6 glucanase produced by myxobacteria can degrade the glycosidic bond of cell wall of some plant pathogenic fungi, resulting in a perforated structure in the cell wall. In addition, isooctanol produced by myxobacteria can lead to the accumulation of intracellular reactive oxygen species in some pathogenic fungi and induce cell apoptosis. Myxobacteria can also perforate the cell wall of some plant pathogenic oomycetes by β-1,3 glucanase, reduce the content of intracellular soluble protein and protective enzyme activity, affect the permeability of oomycete cell membrane, and aggravate the oxidative damage of pathogen cells. Small molecule compounds such as diisobutyl phthalate and myxovirescin produced by myxobacteria can inhibit the formation of biofilm and lipoprotein of bacteria, and cystobactamids can inhibit the activity of DNA gyrase, thus changing the permeability of bacterial cell membrane. Myxobacteria, as a new natural compound resource bank, can control plant pathogenic fungi, oomycetes and bacteria by producing carbohydrate active enzymes and small molecular compounds, so it has great potential in plant disease control.

Antagonistic bacteria against Fusarium spp. isolated from sclerotia of Claviceps gigantea in maize (Zea mays)

Fungal sclerotia house native bacterial populations of interest for biological control of plant pathogenic fungi. The objectives of this research were: i) to explore the bacterial populations associated with Claviceps gigantea sclerotia in maize from six locations in the State of Mexico, ii) to evaluate the in vitro antagonism of these bacterial populations against three species of Fusarium phytopathogens of maize, iii) to molecularly identify the more efficient antagonists and characterize the in vitro production of metabolites. Bacterial populations in the sclerotia were calculated by direct plate count; in vitro antagonism against Fusarium graminearum, F. sublgutinans, and F. verticillioides was evaluated by confrontation in Waksman agar medium. Antagonistic bacteria were identified by partial sequencing of 16S rRNA gene and evaluated in vitro for the production of indole-3 acetic acid, siderophores, lipolytic and proteolytic activity, and mineral phosphate solubilization. The bacterial density ranged from 2.023 to 2.397 Log10UFC g-1 of sclerotia. Twenty-two strains showed in vitro antagonism against at least one Fusarium species and were identified as members of the genera Bacillus, Delftia, Micromonospora, Pseudomonas, Sphingobacterium, Staphylococcus, and Stenotrophomonas. The 22 antagonists showed in vitro lipolytic, proteolytic, siderophore-producing and phosphate-solubilizing activity; only 12 (55%) produced indole-3-acetic acid. Bacillus subtilis (BA1), Pseudomonas syringae (BA2), and Bacillus amyloliquefaciens (BA18) strains were antagonists against the three Fusarium species and produced all the metabolites evaluated.

Durian Shell-Mediated Simple Green Synthesis of Nanocopper against Plant Pathogenic Fungi.

The synthesis of fungicides in eco-friendly and cost-effective ways is significantly essential for agriculture. Plant pathogenic fungi cause many ecological and economic issues worldwide, which must be treated with effective fungicides. Here, this study proposes the biosynthesis of fungicides, which combines copper and Cu2O nanoparticles (Cu/Cu2O) synthesized using durian shell (DS) extract as a reducing agent in aqueous media. Sugar and polyphenol compounds contained in DS, as the main phytochemicals acting in the reduction procedure, were extracted under different temperatures and duration conditions to obtain the highest yields. We confirmed the extraction process performed at 70 °C for 60 min to be the most effective in extracting sugar (6.1 g/L) and polyphenols (22.7 mg/L). We determined the suitable conditions for Cu/Cu2O synthesis using a DS extract as a reducing agent for a synthesis time of 90 min, a volume ratio of DR extract/Cu2+ of 15:35, an initial pH solution of 10, a synthesis temperature of 70 °C, and a CuSO4 concentration of 10 mM. The characterization results of as-prepared Cu/Cu2O NP showed a highly crystalline structure of Cu2O and Cu with sizes estimated in the range of 40-25 nm and 25-30 nm, respectively. Through in vitro experiments, the antifungal efficacy of Cu/Cu2O against Corynespora cassiicola and Neoscytalidium dimidiatum was investigated by the inhibition zone. The green-synthesized Cu/Cu2O nanocomposites, which are potential antifungals against plant pathogens, exhibited excellent antifungal efficacy against both Corynespora cassiicola (MIC = 0.25 g/L, the diameter of the inhibition zone was 22.00 ± 0.52 mm) and Neoscytalidium dimidiatum (MIC = 0.0625 g/L, the diameter of the inhibition zone was 18.00 ± 0.58 mm). Cu/Cu2O nanocomosites prepared in this study could be a valuable suggestion for the control of plant pathogenic fungi affecting crop species globally.

Preparation, biocontrol activity and growth promotion of biofertilizer containing Streptomyces aureoverticillatus HN6.

Nowadays, due to the excessive dependence on chemical fertilizers and pesticides in agricultural production, many problems, such as soil hardening and soil-borne diseases, have become increasingly prominent, which seriously restrict the sustainable development of agriculture. The application of microbial fertilizer prepared by biocontrol microorganisms can not only improve soil structure and increase fertility but also have the function of controlling diseases. Streptomyces aureoverticillatus HN6 has obvious disease prevention and growth promotive effect, which can improve the rhizosphere fertility of plants and even regulate the rhizosphere microbial community of plants. Based on the comparison of frame composting and natural composting, we used the response surface method to optimize the preparation conditions of Streptomyces HN6 bacterial fertilizer. The results showed that natural composting not only produced higher composting temperatures and maintained long high temperature periods in accordance with local conditions, but was also more suitable for composting in the field according to local conditions. Therefore, the substrate's conductivity changed more, the ash accumulation increased, and the substrate decomposed more thoroughly. Thus, this composting method is highly recommended. Additionally, Streptomyces HN6 microbial fertilizer EC20 can reduce cowpea fusarium wilt and promote cowpea growth. The number of plant leaves, plant height and fresh weight, increased significantly in the microbial fertilizer EC20. Moreover, Streptomyces HN6 fertilizer EC20 could significantly induce soil invertase, urease and catalase activities. Our study highlights the potential use of Streptomyces HN6 as a biofertilizer to improve plant productivity and biological control of plant pathogenic fungi.

Weapons against Themselves: Identification and Use of Quorum Sensing Volatile Molecules to Control Plant Pathogenic Fungi Growth.

Quorum sensing (QS) is often defined as a mechanism of microbial communication that can regulate microbial behaviors in accordance with population density. Much is known about QS mechanisms in bacteria, but fungal QS research is still in its infancy. In this study, the molecules constituting the volatolomes of the plant pathogenic fungi Fusarium culmorum and Cochliobolus sativus have been identified during culture conditions involving low and high spore concentrations, with the high concentration imitating overpopulation conditions (for QS stimulation). We determined that volatolomes emitted by these species in conditions of overpopulation have a negative impact on their mycelial growth, with some of the emitted molecules possibly acting as QSM. Candidate VOCs related to QS have then been identified by testing the effect of individual volatile organic compounds (VOCs) on mycelial growth of their emitting species. The antifungal effect observed for the volatolome of F. culmorum in the overpopulation condition could be attributed to ethyl acetate, 2-methylpropan-1-ol, 3-methylbutyl ethanoate, 3-methylbutan-1-ol, and pentan-1-ol, while it could be attributed to longifolene, 3-methylbutan-1-ol, 2-methylpropan-1-ol, and ethyl acetate for C. sativus in the overpopulation condition. This work could pave the way to a sustainable alternative to chemical fungicides.

Isolation, Identification and Hyperparasitism of a Novel Cladosporium cladosporioides Isolate Hyperparasitic to Puccinia striiformis f. sp. tritici, the Wheat Stripe Rust Pathogen.

Simple SummaryObligate biotrophic pathogen Puccinia striiformis f. sp. tritici (Pst) is a major threat to wheat production. Parasites of Pst can be used to develop biological agents for environmentally friendly control of this fungal disease. Here, we report a hyperparasitic fungus isolated from taupe-colored uredinia of Pst and identified as Cladosporium cladosporioides through molecular and morphological characterizations. The hyperparasitic isolate was able to reduce the production and viability of Pst. Therefore, Cladosporium cladosporioides may have potential in biological control of stripe rust on wheat.Wheat rust outbreaks have caused significantly economic losses all over the world. Puccinia striiformis f. sp. tritici (Pst) is an obligate biotrophic fungus causing stripe rust on wheat. Application of fungicides may cause environmental problems. The effects of hyperparasites on plant pathogens are the basis for biological control of plant pathogenic fungi and parasites of Pst have great value in biological agents development. Here, we report the isolation and characterization of isolate of Cladosporium cladosporioides from Pst based on morphological characterization and analysis of molecular markers. The hyperparasitic isolate was isolated from taupe-colored uredinia of Pst. Upon artificial inoculation, the hyperparasitic isolate was able to reduce the production and germination rate of Pst urediospores, and Pst uredinia changed color from yellow to taupe. Scanning electron microscopy demonstrated that the strain could efficiently colonize Pst urediospores. Therefore, the isolate has the potential to be developed into a biological control agent for managing wheat stripe rust.

Evaluation of sulfonated oxidized chitosan antifungal activity against Fusarium graminearum

Chitosan biomaterials are widely used in the biological area because of their broad-spectrum antibacterial activity. However, chitosan cannot be dissolved in a neutral solution, limiting its application in various fields seriously. In this study, water-soluble sulfonated oxidized chitosan (SOCS) with antifungal activity were prepared by oxidization and sulfonation. Its structure was clearly confirmed by spectroscopy data (FTIR, 1H NMR, 13C NMR) and elemental analysis. SEM images of OCS and SOCS revealed that there was a little curly and an irregular sheet-like morphologies on them which was attributed to the oxidation and sulfonation on CS. Moreover, the FTIR and NMR indicated that –OH on the CS was oxidized into -COOH on the OCS and -SO3H groups on the SOCS. The EDS results of OCS and SOCS confirmed the presence of the oxygen element in OCS and the S element in SOCS. All studies confirmed the OCS and SOCS were synthesized successfully. Furthermore, the inhibitory activity of SOCS biocomposites against plant pathogenic fungi, (Fusarium graminearum), was investigated. The results showed that the SOCS have significant inhibitory effects on the mycelial growth of F. graminearum. The EC50 value of SOCS against F. graminearum is 79.46 μg/mL. The research results presented above indicated that SOCS can be used as a candidate material for the control of plant pathogenic fungi, and can broaden the application of chitosan materials in plant protection and sustainable agriculture. Research highlights SOCS showed better solubility in deionized water. The antifungal effect of SOCS dissolved in acetic acid was higher than that of CS dissolved in acetic acid. SOCS dissolved in water can cause an inhibitory effect on F. graminearum at lower concentrations.

Composition and antifungal activity of the essential oils hydrodistilled from three accessions of pastinocello carrot (Daucus carota L. ssp. major)

In line with the actual increasing request of innovative and alternative tools aimed to reduce the use of chemicals in favor of more sustainable agriculture and food systems, natural products, such as essential oils (EOs), represent a valid alternative to pesticides. Essential oils contain antioxidant and antimicrobial constituents able to act against plant pathogens, including phytopathogenic fungi. Despite species belonging to Daucus genus are already known as a source of active essential oils, little is known about D. carota ssp. major (pastinocello), a local carrot variety, now listed among the species facing extinction risk. With the aim to investigate this species, the present work aimed to study three pastinocello accessions cultivated in Central Italy, in terms of bio-agronomic characteristics, inflorescence production, essential oils yield and composition, and their activity against plant pathogenic and beneficial fungi. Results showed significant morphological and productive differences among accessions as well as a significant different composition in their essential oils, with accession L24 richer in oxygenated sesquiterpenes class (such as carotol and daucol) and L281 and L305 showing monoterpene hydrocarbons as the most abundant chemical groups. At the same time the EO obtained from L24 was the most effective in reducing the growth of two important plant pathogenic fungi, Fusarium oxysporum f. sp. lycopersici and Monilinia fructigena, while any effect was observed against two well-known beneficial isolates belonging to Trichoderma genus.These results not only confirm the possibility to use EOs from pastinocello to control plant pathogenic fungi, but also leave open the possibility of a combined use with beneficial Trichoderma isolates, already exploited as biocontrol agents for the management of plant diseases.

Trichogenic Silver-Based Nanoparticles for Suppression of Fungi Involved in Damping-Off of Cotton Seedlings.

Mycogenic silver nanoparticles (AgNPs) produced by some biocontrol agents have shown the ability to inhibit the growth of numerous plant pathogenic fungi, which may be a unique method of disease management. This study describes the extracellular production of AgNPs by Trichoderma harzianum. The size, shape, charge, and composition of the AgNPs were subsequently studied by UV-visible spectroscopy, DLS, zeta potential, TEM, SEM, and EDX, among other methods. The AgNPs had sizes ranging from 6 to 15 nm. The antifungal activities of bio-synthesized AgNPs and two commercial fungicides (Moncut and Maxim XL) were tested against three soil-borne diseases (Fusarium fujikuroi, Rhizoctonia solani, and Macrophomina phaseolina). Cotton seedling illnesses were significantly reduced under greenhouse settings after significant in vitro antifungal activity was documented for the control of plant pathogenic fungi. The use of biocontrol agents such as T. harzianum, for example, may be a safe strategy for synthesizing AgNPs and using them to combat fungus in Egyptian cotton.

Wide distribution of resistance to the fungicides fludioxonil and iprodione in Penicillium species.

Fludioxonil and iprodione are effective fungicides widely used for crop protection and are essential for controlling plant pathogenic fungi. The emergence of fungicide-resistant strains of targeted pathogens is regularly monitored, and several cases have been reported. Non-targeted fungi may also be exposed to the fungicide residues in agricultural fields. However, there are no comprehensive reports on fungicide-resistant strains of non-targeted fungi. Here, we surveyed 99 strains, representing 12 Penicillium species, that were isolated from a variety of environments, including foods, dead bodies, and clinical samples. Among the Penicillium strains, including non-pathogenic P. chrysogenum and P. camembertii, as well as postharvest pathogens P. expansum and P. digitatum, 14 and 20 showed resistance to fludioxonil and iprodione, respectively, and 6 showed multi-drug resistance to the fungicides. Sequence analyses revealed that some strains of P. chrysogenum and Penicillium oxalicum had mutations in NikA, a group III histidine kinase of the high-osmolarity glycerol pathway, which is the mode of action for fludioxonil and iprodione. The single nucleotide polymorphisms of G693D and T1318P in P. chrysogenum and T960S in P. oxalicum were only present in the fludioxonil- or iprodione-resistant strains. These strains also exhibited resistance to pyrrolnitrin, which is the lead compound in fludioxonil and is naturally produced by some Pseudomonas species. This study demonstrated that non-targeted Penicillium strains distributed throughout the environment possess fungicide resistance.

Rapid Isolation of Ricinine, a Pyridone Alkaloid from Ricinus communis (L.) with Antifungal Properties

The present study introduces an effective and rapid method for isolation of antifungal compound ricinine from Ricinus communis (L.). In this respect, the tender leaves of R. communis were extracted using methanol and tested for antifungal activity against a panel of dermatophytes and plant pathogenic fungi. Primarily, the total extract exhibited broad-spectrum antifungal activity with the zones of inhibition ranging from 12 ± 1.00 to 18.66 ± 1.52 mm. Further, investigation of chemical constituents led to the isolation of a cyano-pyridone alkaloid, ricinine using acid-base extraction. The compound exhibited significant antifungal activity with MIC values ranging from 6.25-250 µg/mL against the tested pathogenic fungi. Particularly, antifungal activity was recorded against A. flavus with the MIC value of 7.81 µg/mL followed by B. cinerea and A. niger with 15.62 µg/mL, respectively; T. mentagrophytes and T. rubrum with 62.5 µg/mL, respectively and it showed weak activity against Scopulariopsis sp. with 250 µg/mL. This efficient result provide new insights on large-scale isolation and identification of 4-methoxy-1-methyl-2-oxo-1,2-dihydropyridine-3-carbonitrile (Ricinine) which possess potent antifungal activity. In conclusion, the compound ricinine can be used as potential antifungal agent for controlling plant pathogenic fungi as well dermatophytes. Further, this potentially useful technique is operationally simple, safe, time-saving and inexpensive, and can be applied by medicinal, pharmaceutical and scientific research for the isolation of other potentially useful alkaloids in the drug discovery programs.

Antifungal efficacy of Moringa oleifera leaf and seed extracts against Botrytis cinerea causing gray mold disease of tomato (Solanum lycopersicum L.).

Drawbacks associated with the use of chemical fungicides to control plant pathogenic fungi such as Botrytis cinerea stimulate the need for alternatives. Therefore, the present study was carried out to determine the antifungal potentials of Moringa oleifera extracts against B. cinerea. Phytochemical analysis using qualitative chemical tests revealed the presence of huge amount of crucial phytochemicals compounds like phenolic compounds, alkaloids and saponins in the M. oleifera leaf extract. Antifungal bioassay of the crude extracts indicated better mycelial growth inhibition by methanol leaf extract (99%). The minimum inhibitory concentration (MIC) was 5 mg/ml with 100% spore germination inhibition and minimum fungicidal concentration (MFC) was 10 mg/ml with 98.10% mycelial growth inhibition using broth micro dilution and poisoned food techniques. Gas chromatography-mass spectrometry (GC-MS) analysis led to the identification of 67 volatile chemical compounds in the leaf extract with 6-decenoic acid (Z)- (19.87%) was the predominant compound. Further chemical elucidation of the crude extracts performed by liquid chromatography with tandem mass spectrometry (LC-MS/MS) showed the presence of non-volatile chemical compounds, mostly flavones, flavonoids and phenolic acids (i.e. quercetin and kaempferol). Scanning electron microscopy and transmission electron microscopy analysis showed positive effect of M. oleifera leaf extract on the treated conidia and mycelium of B. cinerea. Findings revealed that irreversible surface and ultra-structural changes with severe detrimental effects on conidia and mycelium morphology compared to control treatment. Overall findings suggested that M. oleifera leaf extract is a promising candidate for biological control of fungal pathogens, thus limiting overdependence on chemical fungicides.

Trends in Nanotechnology and Its Potentialities to Control Plant Pathogenic Fungi: A Review.

Simple SummaryFungal pathogens were reported to cause about 70–80% losses in yield. Nanotechnology can be a panacea to this problem by reducing the negative effect of the fungicides, enhancing the solubility of low water-soluble fungicides, and reducing their toxic effect in a sustainable and eco-friendly manner. This review focuses on the description, properties, and synthesis of nanoparticles, their utilization for plant pathogenic fungal disease control (either in the form of nanoparticles alone, or in the form of a nanocarrier for several fungicides), nano-formulations of agro-nanofungicides, Zataria multiflora, and ginger essential oils to control plant pathogenic fungi, as well as the biosafety and limitations of the nanoparticles applications.Approximately 15–18% of crops losses occur as a result of animal pests, while weeds and microbial diseases cause 34 and 16% losses, respectively. Fungal pathogens cause about 70–80% losses in yield. The present strategies for plant disease control depend transcendently on agrochemicals that cause negative effects on the environment and humans. Nanotechnology can help by reducing the negative impact of the fungicides, such as enhancing the solubility of low water-soluble fungicides, increasing the shelf-life, and reducing toxicity, in a sustainable and eco-friendly manner. Despite many advantages of the utilization of nanoparticles, very few nanoparticle-based products have so far been produced in commercial quantities for agricultural purposes. The shortage of commercial uses may be associated with many factors, for example, a lack of pest crop host systems usage and the insufficient number of field trials. In some areas, nanotechnology has been advanced, and the best way to be in touch with the advances in nanotechnology in agriculture is to understand the major aspect of the research and to address the scientific gaps in order to facilitate the development which can provide a rationale of different nanoproducts in commercial quantity. In this review, we, therefore, described the properties and synthesis of nanoparticles, their utilization for plant pathogenic fungal disease control (either in the form of (a) nanoparticles alone, that act as a protectant or (b) in the form of a nanocarrier for different fungicides), nano-formulations of agro-nanofungicides, Zataria multiflora, and ginger essential oils to control plant pathogenic fungi, as well as the biosafety and limitations of the nanoparticles applications.

Tebuconazole induced cytotoxic and genotoxic effects in HCT116 cells through ROS generation

Tebuconazole (TEB) is a common triazole fungicide that has been widely used for the control of plant pathogenic fungi, suggesting that mammal exposure occurs regularly. Several studies demonstrated that TEB exposure has been linked to a variety of toxic effects, including neurotoxicity, immunotoxicity, reprotoxicity and carcinogenicity. However, there is a few available data regarding the molecular mechanism involved in TEB-induced toxicity. The current study was undertaken to investigate the toxic effects of TEB in HCT116 cells. Our results showed that TEB caused cytotoxicity by inhibiting cell viability as assessed by the MTT assay. Furthermore, we have demonstrated that TEB induced a significant increase in the reactive oxygen species (ROS) production leading to the induction of lipid peroxidation and DNA fragmentation and increased superoxide dismutase (SOD) and catalase (CAT) activities. Moreover, TEB exposure induced mitochondrial membrane potential loss and caspase-9/-3 activation. Treatment with general caspases inhibitor (Z-VAD-fmk) significantly prevented the TEB-induced cell death, indicating that TEB induced caspases-dependent cell death. These findings suggest the involvement of oxidative stress and apoptosis in TEB-induced toxicity in HCT116.

The use of Marrubium vulgare L. plant extracts in the control of fungal plant pathogens

In this study, we investigated anti-fungal properties of Marrubium vulgare L. plant extracts dissolved in four different solvents against five different plant pathogenic fungi Fusarium oxysporum f. sp. lycopersici, Macrophamina phaseolina, Phytopthora infestans, Sclerotinia sclerotiorum and Rhizoctania solani. We used 1.0%, 2.5% and 5.0% plant extract concentrations against these fungi species which cause significant decrease in production yield of certain plants. In all pathogenic fungi species analyzed, we observed an increase in the anti-fungal effect of Marrubium vulgare L. plant extract preparations in a dose-dependent manner. Marrubium vulgare L. extracts dissolved in chloroform and dichloromethane at 2.5% concentration showed higher inhibition against Fusarium oxysporum compared to other solvents at this concentration. At the same concentration, extracts dissolved in methanol resulted in higher anti-fungal activity against Phytopthora infestans and intermediate activity against Macrophamina phaseolina and Sclerotinia sclerotiorum. As a result, it can be stated that Marrubium vulgare L. plant extracts dissolved in different solvents display anti-fungal properties against certain plant pathogens.

Preliminary Study on the Activity of Phycobiliproteins against Botrytis cinerea.

Phycobiliproteins (PBPs) are proteins of cyanobacteria and some algae such as rhodophytes. They have antimicrobial, antiviral, antitumor, antioxidative, and anti-inflammatory activity at the human level, but there is a lack of knowledge on their antifungal activity against plant pathogens. We studied the activity of PBPs extracted from Arthrospira platensis and Hydropuntia cornea against Botrytis cinerea, one of the most important worldwide plant-pathogenic fungi. PBPs were characterized by using FT-IR and FT-Raman in order to investigate their structures. Their spectra differed in the relative composition in the amide bands, which were particularly strong in A. platensis. PBP activity was tested on tomato fruits against gray mold disease, fungal growth, and spore germination at different concentrations (0.3, 0.6, 1.2, 2.4, and 4.8 mg/mL). Both PBPs reduced fruit gray mold disease. A linear dose–response relationship was observed for both PBPs against disease incidence and H. cornea against disease severity. Pathogen mycelial growth and spore germination were reduced significantly by both PBPs. In conclusion, PBPs have the potential for being also considered as natural compounds for the control of fungal plant pathogens in sustainable agriculture.

Multi potent aromatic nano colloid: synthesis, characterization and applications

In this study the aromatic nanocolloids (CANCs) are synthesized using the noble metal silver by using Citronella extract and confirmed through physio chemical analysis. The synthesised CANCs were evaluated for its antimicrobial activity and antibiofilm activity against pathogenic biofilm forming E. coli. In addition, synthesized CANCs were evaluated for the expression of virulent genes encoding AmpC and CTX-M-15. The results confirmed that CANCs showed effective antimicrobial activity through its bacteriostatic, bactericidal and quorum quencher activity and downregulated CTX-M-15 gene. CANCs were validated as alternate to the commercial fungicides to control plant pathogenic fungi such as A. niger MTCC (281), Fusarium graminearum MTCC (2089) and F. udum MTCC (2204). Furthermore, analysis of CANCs on breast cancer (MCF-7) cells under in vitro condition showed that the cytotoxicity of CANCs is dose dependent. Thus, the multifunctional CANCs can be utilized as potential antimicrobial, antifungal and anticancer agent.