Multifunctional characteristics of Acinetobacter lwoffii Bac109 for growth promotion and colonization in micropropagated sugarcane

2021 ◽  
Vol 51 ◽  
Author(s):  
Janniffer Custódio da Silva ◽  
Luan Dionisio Silva Santos ◽  
Paula Sperotto Alberto Faria ◽  
Fabiano Guimarães Silva ◽  
Aurélio Rubio Neto ◽  
...  
Keyword(s):  
Biocontrol Agent ◽  
Growth Promotion ◽  
Low Cost ◽  
Phytopathogenic Fungi ◽  
Root Extract ◽  
Vitro Assay ◽  
Biofilm Production ◽  
Strong Adhesion ◽  
Better Than

ABSTRACT Endophytic bacteria with multifunctional characteristics can benefit plants through different mechanisms, as well as promoting growth in an efficient, low-cost and ecofriendly way. This study analyzed the potential of the multifunctional endophytic isolate Acinetobacter lwoffii Bac109 in promoting the early in vitro growth of sugarcane seedlings. The Bac109 strain showed potential to solubilize phosphate in a solid medium (solubilization index: 3.73). In addition, the bacterium was an efficient biocontrol agent against the phytopathogenic fungi Rhizoctonia sp., Fusarium oxysporum, Phoma sp. and Bipolaris papendorfii, showing a performance equal to or better than the commercial antifungal hygromycin B. An in vitro assay confirmed the biofilm production, which increased in the presence of sugarcane root extract. Additionally, A. lwoffii Bac109 showed a strong adhesion to the sugarcane roots. The inoculation of this bacterium in micropropagated sugarcane seedlings increased the shoot length (35 %) and regulated the nonphotochemical energy dissipation after 28 days of cultivation. At the end of the experiment, the bacterium showed a great potential for survival, with 5.72 × 107 CFU mL-1 recovered from the substrate, what is crucial for plant interaction. The results showed the potential of the biotechnology application for A. lwoffii Bac109 by evaluating multifunctional traits of plant growth promotion and by specific interactions with sugarcane, which may help to improve micropropagation protocols for this crop.

Effect of the endophytic plant growth promoting Enterobacter ludwigii EB4B on tomato growth

2020 ◽  
Vol 13 (2) ◽  
pp. 54-65 ◽  
Author(s):  
M.E.A. Bendaha ◽  
H.A. Belaouni
Keyword(s):  
Root Length ◽  
Biocontrol Agent ◽  
Growth Promotion ◽  
Dry Weight ◽  
Antagonistic Activity ◽  
Rrna Gene ◽  
Plant Growth Promoting ◽  
Enterobacter Ludwigii ◽  
Tomato Growth

SummaryThis study aims to develop a biocontrol agent against Fusarium oxysporum f.sp. radicis-lycopersici (FORL) in tomato. For this, a set of 23 bacterial endophytic isolates has been screened for their ability to inhibit in vitro the growth of FORL using the dual plate assay. Three isolates with the most sound antagonistic activity to FORL have been qualitatively screened for siderophore production, phosphates solubilization and indolic acetic acid (IAA) synthesis as growth promotion traits. Antagonistic values of the three candidates against FORL were respectively: 51.51 % (EB4B), 51.18 % (EB22K) and 41.40 % (EB2A). Based on 16S rRNA gene sequence analysis, the isolates EB4B and EB22K were closely related to Enterobacter ludwigii EN-119, while the strain EB2A has been assigned to Leclercia adecarboxylata NBRC 102595. The promotion of tomato growth has been assessed in vitro using the strains EB2A, EB4B and EB22K in presence of the phytopathogen FORL. The treatments with the selected isolates increased significantly the root length and dry weight. Best results were observed in isolate EB4B in terms of growth promotion in the absence of FORL, improving 326.60 % of the root length and 142.70 % of plant dry weight if compared with untreated controls. In the presence of FORL, the strain EB4B improved both root length (180.81 %) and plant dry weight (202.15 %). These results encourage further characterization of the observed beneficial effect of Enterobacter sp. EB4B for a possible use as biofertilizer and biocontrol agent against FORL.

scholarly journals A Metabolomic Study of Epichloë Endophytes for Screening Antifungal Metabolites

Metabolites ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 37
Author(s):  
Krishni Fernando ◽  
Priyanka Reddy ◽  
Kathryn M. Guthridge ◽  
German C. Spangenberg ◽  
Simone J. Rochfort
Keyword(s):  
Phytopathogenic Fungi ◽  
Bioactive Metabolites ◽  
Symbiotic Association ◽  
In Planta ◽  
Vitro Assay ◽  
Antifungal Metabolites ◽  
Bioassay Guided Fractionation ◽  
Toxic Alkaloids ◽  
Epichloë Endophytes

Epichloë endophytes, fungal endosymbionts of Pooidae grasses, are commonly utilized in forage and turf industries because they produce beneficial metabolites that enhance resistance against environmental stressors such as insect feeding and disease caused by phytopathogen infection. In pastoral agriculture, phytopathogenic diseases impact both pasture quality and animal production. Recently, bioactive endophyte strains have been reported to secrete compounds that significantly inhibit the growth of phytopathogenic fungi in vitro. A screen of previously described Epichloë-produced antifeedant and toxic alkaloids determined that the antifungal bioactivity observed is not due to the production of these known metabolites, and so there is a need for methods to identify new bioactive metabolites. The process described here is applicable more generally for the identification of antifungals in new endophytes. This study aims to characterize the fungicidal potential of novel, ‘animal friendly’ Epichloë endophyte strains NEA12 and NEA23 that exhibit strong antifungal activity using an in vitro assay. Bioassay-guided fractionation, followed by metabolite analysis, identified 61 metabolites that, either singly or in combination, are responsible for the observed bioactivity. Analysis of the perennial ryegrass-endophyte symbiota confirmed that NEA12 and NEA23 produce the prospective antifungal metabolites in symbiotic association and thus are candidates for compounds that promote disease resistance in planta. The “known unknown” suite of antifungal metabolites identified in this study are potential biomarkers for the selection of strains that enhance pasture and turf production through better disease control.

scholarly journals Biosensors to Monitor Water Quality Utilizing Insect Odorant-Binding Proteins as Detector Elements

Biosensors ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 62 ◽  
Author(s):  
Spiros D. Dimitratos ◽  
Allison S. Hommel ◽  
Kenneth D. Konrad ◽  
Lauren M. Simpson ◽  
Jessica J. Wu-Woods ◽  
...  
Keyword(s):  
Recombinant Expression ◽  
Low Cost ◽  
Coliform Bacteria ◽  
Waterborne Diseases ◽  
Water Safety ◽  
Water Supplies ◽  
Vitro Assay ◽  
Ligand Selectivity ◽  
Odorant Binding

In the developing world, the identification of clean, potable water continues to pose a pervasive challenge, and waterborne diseases due to fecal contamination of water supplies significantly threaten public health. The ability to efficiently monitor local water supplies is key to water safety, yet no low-cost, reliable method exists to detect contamination quickly. We developed an in vitro assay utilizing an odorant-binding protein (OBP), AgamOBP1, from the mosquito, Anopheles gambiae, to test for the presence of a characteristic metabolite, indole, from harmful coliform bacteria. We demonstrated that recombinantly expressed AgamOBP1 binds indole with high sensitivity. Our proof-of-concept assay is fluorescence-based and demonstrates the usefulness of insect OBPs as detector elements in novel biosensors that rapidly detect the presence of bacterial metabolic markers, and thus of coliform bacteria. We further demonstrated that rAgamOBP1 is suitable for use in portable, inexpensive “dipstick” biosensors that improve upon lateral flow technology since insect OBPs are robust, easily obtainable via recombinant expression, and resist detector “fouling.” Moreover, due to their wide diversity and ligand selectivity, insect chemosensory proteins have other biosensor applications for various analytes. The techniques presented here therefore represent platform technologies applicable to various future devices.

scholarly journals ANTIOXIDANT ACTIVITY AND TOTAL PHENOL AND FLAVONOIDS ANALYSIS OF SIBERIAN GINSENG ROOT

2020 ◽  
pp. 38-40
Author(s):  
NAGENDAR SHETTY ◽  
V. HARIKA ◽  
SUMITRA LOKRAS
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging ◽  
Reducing Power ◽  
Total Phenol ◽  
Ginseng Root ◽  
Root Extract ◽  
Frap Assay ◽  
Vitro Assay ◽  
Siberian Ginseng

Objective: This study was examined to in vitro antioxidant activity and Total Phenol and Flavonoids content analysis of methanolic root extract of Eleutherococcus senticosus (Siberian ginseng). Methods: 1,1-dephenyl-2-picryl-hydrazyl free radical scavenging and FRAP assay propose that antioxidant activity of methanol root extract because of reducing capacity of the antioxidant against oxidative effects of reactive oxygen species. Results: Scavenging activity of Siberian ginseng root RC50 value was shown 713.42±11.55 µg/ml and reducing power 0.13±0.01 mmol/g was investigated. In addition, total phenol 12.6±1.13 mg GAE/g DW and total flavonoids 9.8±0.20 mg QE/g DW were recorded. Conclusion: Although all tests were performed in vitro assay, these results recommend that Siberian ginseng root may be a good source of antioxidant ingrediant.

In Vitro α-glucosidase Inhibition and Computational Studies of Kaempferol Derivatives from Dryopteris cycanida

2020 ◽  
Vol 20 (9) ◽  
pp. 731-737 ◽  
Author(s):  
Surriya Amin ◽  
Barkat Ullah ◽  
Mumtaz Ali ◽  
Haroon Khan ◽  
Abdur Rauf ◽  
...  
Keyword(s):  
Computational Studies ◽  
Vitro Assay ◽  
Pharmacological Studies ◽  
Standard Compound ◽  
Dependent Inhibition ◽  
Human Disorders ◽  
Ic50 Values ◽  
Phytochemical Studies ◽  
Better Than

Background: Dryopteris cycadina has diverse traditional uses in the treatment of various human disorders which are supported by pharmacological studies. Similarly, the phytochemical studies of this plant led to the isolation of numerous compounds. Methodology: The present study deals with α-glucosidase inhibition of various kaempferol derivates including kaempferol-3, 4/-di-O-α- L-rhamnopyranoside 1, kaempferol-3, 5-di-O-α-L-rhamnoside 2 and kaempferol-3,7-di-O-α- L-rhamnopyranoside 3. Results: The results showed marked concentration-dependent inhibition of the enzyme when assayed at different concentrations and the IC50 values of compounds 1-3 were 137±9.01, 110±7.33, and 136±1.10 mM, respectively far better than standard compound, acarbose 290±0.54 mM. The computational studies revealed strong docking scores of these compounds and augmented the in vitro assay. Conclusion: In conclusion, the isolated kaempferol derivatives 1-3 from D. cycadina exhibited potent α- glucosidase inhibition.

scholarly journals Cladobotryum mycophilum as Potential Biocontrol Agent

Agronomy ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 891
Author(s):  
Mila Santos ◽  
Fernando Diánez ◽  
Alejandro Moreno-Gavíra ◽  
Brenda Sánchez-Montesinos ◽  
Francisco J. Gea
Keyword(s):  
Biological Control ◽  
Fusarium Oxysporum ◽  
Biocontrol Agent ◽  
Biological Control Agent ◽  
Control Agent ◽  
Phytopathogenic Fungi ◽  
Antagonistic Activity ◽  
Dual Culture ◽  
Potential Biocontrol Agent

A study was conducted to explore the efficacy of potential biocontrol agent Cladobotryum mycophilum against different phytopathogenic fungi. The growth rates of 24 isolates of C. mycophilum were determined, and their antagonistic activity was analysed in vitro and in vivo against Botrytis cinerea, Fusarium oxysporum f. sp. radicis-lycopersici, Fusarium oxysporum f.sp. cucumerinum, Fusarium solani, Phytophthora parasitica, Phytophthora capsici, Pythium aphanidermatum and Mycosphaerella melonis. Most isolates grow rapidly, reaching the opposite end of the Petri dish within 72–96 h. Under dual-culture assays, C. mycophilum showed antagonistic activity in vitro against all phytopathogenic fungi tested, with mycelial growth inhibition ranging from 30 to 90% against all the different phytopathogens tested. Similarly, of all the selected isolates, CL60A, CL17A and CL18A significantly (p < 0.05) reduced the disease incidence and severity in the plant assays compared to the controls for the different pathosystems studied. Based on these results, we conclude that C. mycophilum can be considered as a potential biological control agent in agriculture. This is the first study of Cladobotryum mycophilum as a biological control agent for different diseases caused by highly relevant phytopathogens in horticulture.

scholarly journals Hypertonic saline solution inhibits SARS-CoV-2 in vitro assay

2020 ◽  
Author(s):  
Rafael R. G. Machado ◽  
Talita Glaser ◽  
Danielle B. Araujo ◽  
Lyvia Lintzmaier Petiz ◽  
Danielle B. L. Oliveira ◽  
...  
Keyword(s):  
Hypertonic Saline ◽  
Virus Replication ◽  
Saline Solution ◽  
Low Cost ◽  
Vero Cells ◽  
Hypertonic Saline Solution ◽  
Vitro Assay ◽  
Health Crisis ◽  
Angiotensin Converting Enzyme 2

AbstractWe are facing an unprecedented global health crisis caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). At this date more than 680 thousand people have died due to coronavirus disease 2019 (COVID-19). Unfortunately, until now no effective treatment to combat the virus and vaccine are available. We performed experiments to test if hypertonic saline solution is able to inhibit virus replication in vitro. Our data shows that 260 mM NaCl (1.5%) inhibits 100% SARS-CoV-2 replication in Vero cells. Furthermore, our results suggest that the virus replication inhibition is due to an intracellular mechanism and not due to the dissociation between spike SARS-CoV-2 protein and its human receptor angiotensin-converting enzyme 2 interaction. NaCl depolarizes the plasma membrane supposedly associated with the inhibition of the SARS-CoV-2 life cycle. This observation could lead to simple, safe and low cost interventions at various stages of COVID-19 treatment, improving the prognosis of infected patients, thereby mitigating the social and economic costs of the pandemic.

scholarly journals Chitinolytic and Antagonistic Activity of Streptomyces Isolated from Fadama Soil against Phytopathogenic Fungi

2021 ◽  
Vol 32 (3) ◽  
pp. 25-38
Author(s):  
Aminu Argungu Umar ◽  
Aminu Bandam Hussaini ◽  
Jibril Yahayya ◽  
Ibrahim Sani ◽  
Habiba Aminu
Keyword(s):  
Antifungal Agents ◽  
Biocontrol Agent ◽  
Specific Activity ◽  
Extracellular Enzyme ◽  
Chitinase Activity ◽  
Phytopathogenic Fungi ◽  
Antagonistic Activity ◽  
Different Temperatures ◽  
Chitinase Production

Chitinases which degrade chitin have attracted attention as biological antifungal agents. The purpose of this study is to isolate Streptomyces from Fadama soil and assess its chitinolytic and antagonist potential against phytopathogenic fungi for application as biocontrol agent. Streptomyces were isolated from Fadama soil. The selected isolate CT02 exhibited chitinolytic characteristics. Chitinase production was performed under different temperatures, pH and varying incubation period. The highest chitinase production by CT02 isolate was observed after five days of cultivation. The highest chitinase activity was observed at 35°C and pH 7. The crude extracellular enzyme exhibited a specific activity of 4.20 U/μg whereas partially purified extracellular enzyme exhibited a specific activity of 6.19 U/μg with purification fold of 1.47. The selected isolate CT02 and its extracellular crude chitinase showed in vitro antifungal antagonist potential by inhibiting the growth of Aspergillus niger and Aspergillus oryzae. This indicates that Streptomyces derived chitinases are potential biocontrol agents against phytopathogenic fungi.

scholarly journals Identification of Trypanosoma cruzi Growth Inhibitors with Activity In Vivo within a Collection of Licensed Drugs

2021 ◽  
Vol 9 (2) ◽  
pp. 406
Author(s):  
Nieves Martinez-Peinado ◽  
Nuria Cortes-Serra ◽  
Julian Sherman ◽  
Ana Rodriguez ◽  
Juan M. Bustamante ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Specific Activity ◽  
Low Cost ◽  
Chronic Phase ◽  
Vero Cells ◽  
Host Cells ◽  
Vitro Assay ◽  
Specific Selectivity

Chagas disease, caused by the parasite Trypanosoma cruzi (T. cruzi), affects more than six million people worldwide, with its greatest burden in Latin America. Available treatments present frequent toxicity and variable efficacy at the chronic phase of the infection, when the disease is usually diagnosed. Hence, development of new therapeutic strategies is urgent. Repositioning of licensed drugs stands as an attractive fast-track low-cost approach for the identification of safer and more effective chemotherapies. With this purpose we screened 32 licensed drugs for different indications against T. cruzi. We used a primary in vitro assay of Vero cells infection by T. cruzi. Five drugs showed potent activity rates against it (IC50 < 4 µmol L−1), which were also specific (selectivity index >15) with respect to host cells. T. cruzi inhibitory activity of four of them was confirmed by a secondary anti-parasitic assay based on NIH-3T3 cells. Then, we assessed toxicity to human HepG2 cells and anti-amastigote specific activity of those drugs progressed. Ultimately, atovaquone-proguanil, miltefosine, and verapamil were tested in a mouse model of acute T. cruzi infection. Miltefosine performance in vitro and in vivo encourages further investigating its use against T. cruzi.

Methylation of arsenic in vitro by cell extracts from bentgrass (Agrostis tenuis): effect of acute exposure of plants to arsenate

2002 ◽  
Vol 29 (1) ◽  
pp. 73 ◽  
Author(s):  
JieHua Wu ◽  
Ren Zhang ◽  
Ross McC. Lilley
Keyword(s):  
Acute Exposure ◽  
Root Extract ◽  
Leaf Extracts ◽  
Vitro Assay ◽  
Root Extracts ◽  
Cell Extracts ◽  
Agrostis Tenuis ◽  
Mammalian Tissues ◽  
Methylation Activity

Compared with microorganisms and mammalian tissues, information is scant on the enzymes responsible for arsenic metabolism in plants. This study investigated the arsenic methylation activities extractable from leaves and roots of Agrostis tenuis Sibth. plants grown in complete nutrient media and exposed to arsenate (135–538 M) for 3 d before harvesting. Methylation activity was determined in leaf and root extracts using an in vitro assay based onS-[3H-methyl]adenosyl-L-methionine (3H-SAM) with either arsenite or arsenate as substrate. Arsenite methylation activity was low in leaf extracts from plants not exposed to arsenate, but was greatly enhanced after acute exposure, with the induced methylation activity greatest in extracts from plants exposed to 269 M arsenate. Monomethylarsonate (MMA) was the predominant early product, but over longer assay times dimethylarsinate (DMA) accumulated at the rate of 660 amol mg protein–1 min–1 to levels exceeding MMA. With arsenate as substrate, methylation activity was much lower than with arsenite, implying that arsenite is the preferred substrate for methylation. Root extract assays exhibited no DMA, however small amounts of MMA were formed with arsenite as substrate. In contrast to leaves, the methylation activity did not increase in root extracts from plants exposed to arsenate. These findings suggest that arsenate in the plant growth medium was taken up by the roots and converted to arsenite before methylation proceeded in the leaves, accompanied by induction of arsenic methyltransferase activities.

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