scholarly journals Infestation of tall fescue (Festuca arundinacea Schreb.) with Neotyphodium coenophialum and its influence on growth of chosen microorganisms in vitro

2012 ◽  
Vol 58 (2) ◽  
pp. 369-380 ◽  
Author(s):  
Dariusz Pańka

Occurrence of <i>Neotyphodium coenophialum</i> in tall fescue cultivars cultivated in Poland and determination an endophyte inhibition effect on mycelium growth of chosen microorganisms <i>in vitro</i> were investigated. Seventeen seed lots of 11 cultivars of tall fescue were examined. The endophyte mycelium was dyed with bengal rose and microscopically examined to detect <i>N. coenophialum</i>. Occurrence of endophyte was checked with PCR method. Influence of endophyte on growth of 15 microorganisms was established in the laboratory conditions on Petri dishes with PDA medium at 10, 20 and 30<sup>°</sup>C. <i>Neotyphodium coenophialum</i> occurred only in two seed lots, 'Barrocco' - 42% and Terros - 2%. Living mycelium of endophyte was isolated only from 'Barrocco'. The highest mycelium growth inhibition of <i>Bipolaris sorokiniana</i>, <i>Fusarium avenaceum</i>, <i>F. equiseti</i>, <i>Microdochium nivale</i> and <i>Gaeumannomyces graminis</i> by endophyte at 30<sup>°</sup>C was recorded. The highest width of growth inhibition zone (4mm) was detected for the last pathogen. Mycelium growth of <i>B. sorokiniana</i> and <i>M. nivale</i> was not inhibited at 10<sup>°</sup>C, and for <i>F. avenaceum</i> at 10 and 20<sup>°</sup>C.

2004 ◽  
Vol 4 (2) ◽  
pp. 83-88
Author(s):  
Efri Efri ◽  
Titik Nur Aeny

Effectivity of  Morinda citrifolia extract on in-vitro growth inhibition of Ralstonia sp.  Morinda citrifolia has been known as one of plants having numerous medicinal properties.  Extract of the fruits shows antibacterial activity against several bacteria including Pseudomonas aeruginosa.  The purpose of this study was to observe inhibitor effect of  M. citrifolia fruit extract, and to investigate the effect of different concentrations of  M. citrifolia fruit extract on in-vitro growth of  Ralstonia (Pseudomonas) sp., the causal agent of banana bacterial wilt disease in Lampung.  Inhibition effect of  M. citrifolia was determined by the presence of inhibition zone, and concentration effect was determined by the diameter of  inhibition zone . The study consisted of two experiments.  The treatments of the first experiment were three different kinds of fruit extract, namely the whole fruit, the seeds, and the fleshy parts, and the second one consisted of six different levels of extract concentrations.  The results showed that the whole fruit extract was the most effective as an in-vitro growth inhibitor, and the higher the concentration level the higher the growth inhibition zone formed.


2018 ◽  
Vol 5 (2) ◽  
Author(s):  
Nyoman Mastra

AbstractBackground Staphylococcus aureus is one of causes infection and this bacteria have been resistence for many antibiotic. Bay leaf have antibacterials substance, which stew leaves can be treat infection caused Staphylococcus aureus. The purpose of this study was to determine differences in growth inhibition zone of Staphylococcus aureus at various concentrations of water stew of bay leaf.Method The method of this study is true experiment with posstest only control design, and used Kirby Bauer disk diffusion method with various concentrations of water stewed of bay leaf (20%, 40%, 60%, 80%,100%), positive control (chloramfenicol 30 μg) and negative control (sterile distilled water). Result The result showed that the average diameter of inhibition zone in concentration 20%, 40%, 60%, 80%, and 100% is 7 mm, 8,4 mm, 9,6 mm, 10,5 mm and 11,5 mm. Based on statistical analysis using oneway ANOVA available the value of p (0,000) α (0,05), so the inhibition zone is significant difference of growth inhibition zone of Staphylococcus aureus at various concentrations of stewed water bay leaf. Conclusion Water stew of bay leaf can inhibit the growth of Staphylococcus aureus, and there are differences in growth inhibition zone of Staphylococcus aureus at various concentrations of water stew of bay leaf. Keywords: stew of bay leaf; Staphylococcus aureus; inhibition zone 


2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Nyoman Mastra

ABSTRACTBackground Staphylococcus aureus is a pathogenic bacteria that can cause infection. Biduri leaf has antibacterial compound such as tannin, flavonoid, saponin, and polyphenol.Objective This study aimed to know the difference of growth inhibition zone of Staphylococcus aureus at the various concentration of ethanol extract of biduri leaf and to determine an effective concentration.Methods This study was the true experiment with posttest only control design, used Kirby-Bauer disk diffusion method with five concentrations (20%, 40%, 60%, 80%,100%), positive control (chloramphenicol 30 µg) and negative control (ethanol 96%).Result The result of this study showed the average of inhibition zone diameter of each concentration consecutively 26,2 mm, 28,3 mm, 29,7 mm, 31 mm and 31,5 mm. One Way Anova statistic analysis showed that the value of p is 0.000 so there is the difference of growth inhibition zone of Staphylococcus aureus at various concentrations of ethanol extract of a biduri leaf.Conclusion The conclusion of this study is there are differences in growth inhibition zone of Staphylococcus aureus at various concentrations of ethanol extract of biduri leaf and an effective concentration that can inhibit of Staphylococcus aureus is concentration 20% with mean inhibition zone is 26,2 mm. Keywords: ethanol extract of biduri leaf; Staphylococcus aureus; inhibition zone


2016 ◽  
Vol 2016 ◽  
pp. 1-6 ◽  
Author(s):  
Farnaz Hajifattahi ◽  
Elham Moravej-Salehi ◽  
Maryam Taheri ◽  
Arash Mahboubi ◽  
Mohammad Kamalinejad

Objectives. This study aimed to assess the effect of hydroalcoholic extract ofPunica granatumLinn. (P. granatum) petal onStreptococcus sanguinis,Streptococcus mutans,Streptococcus salivarius,Streptococcus sobrinus,andEnterococcus faecalis.Materials and Methods. In this in vitro study,P. granatumextract was prepared using powdered petals and water-ethanol solvent. Antibacterial effect of the extract, chlorhexidine (CHX), and ampicillin was evaluated on brain heart infusion agar (BHIA) using the cup-plate method. By assessing the diameter of the growth inhibition zone, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract were determined for the above-mentioned bacteria.Results. Hydroalcoholic extract ofP. granatumpetal had inhibitory effects on the proliferation of all five bacterial strains with maximum effect onS. mutanswith MIC and MBC of 3.9 mg/mL. The largest growth inhibition zone diameter belonged toS. sanguinisand the smallest toE. faecalis. Ampicillin and CHX had the greatest inhibitory effect onS. sanguinis.Conclusions. Hydroalcoholic extract ofP. granatumhad a significant antibacterial effect on common oral bacterial pathogens with maximum effect onS. mutans, which is the main microorganism responsible for dental plaque and caries.


2021 ◽  
Vol 2021 ◽  
pp. 1-7
Author(s):  
Behnam Bolhari ◽  
Aidin Sooratgar ◽  
Maryam Pourhajibagher ◽  
Nazanin Chitsaz ◽  
Iman Hamraz

Enterococcus faecalis is the dominant microorganism in chronic apical periodontitis. It is more resistant to local antiseptic agents than other endodontic microorganisms. Currently, mineral trioxide aggregate (MTA) is considered as an ideal material in many endodontic procedures. Some studies have shown that MTA has good antibacterial activity against E. faecalis. However, some studies have investigated the effect of incorporating some materials into MTA on its antibacterial activity against E. faecalis. No study has evaluated the effect of incorporating fluorohydroxyapatite nanoparticles (nano-FHA) on the antimicrobial activity of MTA. Therefore, the present study evaluated the antimicrobial effect of MTA mixed with nano-FHA on E. faecalis in vitro. The study was carried out on 18 samples in three groups: pure MTA, MTA mixed with 10 wt% of nano-FHA, and MTA mixed with 15 wt% of nan-FHA. The effect of nano-FHA on the antibacterial activity of MTA on E. faecalis was evaluated by evaluating the growth inhibition zone around each sample. The antimicrobial effect of samples on inhibiting E. faecalis biofilm formation and inhibiting microbial growth of E. faecalis in the planktonic phase was evaluated by disk agar diffusion (DAD), biofilm inhibition assay (BIA), and direct contact assay (DCA) tests, respectively. All the above tests were analyzed after 24 and 72 hours. Factorial designs were used for statistical analyses. Tukey tests were used for two-by-two comparisons. All the statistical analyses were carried out with SPSS 26. DAD results showed no formation of the growth inhibition zone in all the samples after 24 and 72 hours. The microbial colony counts in the BIA and DCA tests in the groups modified with FHA nanoparticles were significantly lower than the pure MTA group ( P < 0.05 ). The microbial colony counts increased in all the groups over time ( P < 0.05 ). Incorporating nano-FHA into MTA improved the antimicrobial activity of MTA against E. faecalis compared to pure MTA. The highest antimicrobial activity was achieved after incorporating 15 wt% of nano-FHA into MTA at the 72-hour interval.


2005 ◽  
Vol 62 (5) ◽  
pp. 383-387
Author(s):  
Marija Toskic-Radojicic ◽  
Zorka Nonkovic

Backgraund. Officinal basis for the antibiotic ointments according to the 4th Yugoslav Pharmacopoeia is a hydrophobic base containing only aliphatic hydrocarbons. The fact that antibiotics are predominantly not lipophylic raises the question about the suitability of that particular type of the base for the manufacturing of antibiotic ointments. Recent studies of the lipid analysis of the skin corneal layer indicated that lipids had shown the bilamellar organization in the skin intercorneal space. Such structural organization could be seen in the ambiphylic bases whose structure was based on carefully selected emulsifier couple, consisting of the lyotropic and thermotropic liquid crystals. The aim of this study was to test the velocity of antibiotics (klindamycin hydrochloride, erythromycin base and chloramphenicol) release from the hydrophobic ointment-type bases, and from ambiphylic bases of anionic and non-ionic types. Methods. Membrane-free agar diffusion test as the basic method for testing the release velocity in vitro and Staphylococcus aureus as the strain highly susceptible to the chosen antibiotics were used. All the analyzed samples were manufactured as the suspension-type ointments. Results. The highest growth inhibition zone of the Staphylococcus aureus strain for all three analyzed antibiotics was achieved from the non-ionogenic ambiphylic base; the clear growth inhibition zone area for Staphylococcus aureus strain in the preparations containing anionic ambiphylic base was smaller by 10-31.28%, and in the preparations containing aliphatic hydrocarbon-type base, the decrease was 11.46-31.28%, compared to the results achieved with the non-ionogenic ambiphylic base. Conclusion. The optimal release velocity for the analyzed antibiotics was achieved from the non-ionic ambiphylic base.


Toxins ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 152 ◽  
Author(s):  
Lucile Pellan ◽  
Noël Durand ◽  
Véronique Martinez ◽  
Angélique Fontana ◽  
Sabine Schorr-Galindo ◽  
...  

The aim of this study was to investigate the impact of commercialized biological control agents (BCAs) against two major mycotoxigenic fungi in cereals, Fusarium graminearum and Fusarium verticillioides, which are trichothecene and fumonisin producers, respectively. With these objectives in mind, three commercial BCAs were selected with contrasting uses and microorganism types (T. asperellum, S. griseoviridis, P. oligandrum) and a culture medium was identified to develop an optimized dual culture bioassay method. Their comportment was examined in dual culture bioassay in vitro with both fusaria to determine growth and mycotoxin production kinetics. Antagonist activity and variable levels or patterns of mycotoxinogenesis inhibition were observed depending on the microorganism type of BCA or on the culture conditions (e.g., different nutritional sources), suggesting that contrasting biocontrol mechanisms are involved. S. griseoviridis leads to a growth inhibition zone where the pathogen mycelium structure is altered, suggesting the diffusion of antimicrobial compounds. In contrast, T. asperellum and P. oligandrum are able to grow faster than the pathogen. T. asperellum showed the capacity to degrade pathogenic mycelia, involving chitinolytic activities. In dual culture bioassay with F. graminearum, this BCA reduced the growth and mycotoxin concentration by 48% and 72%, respectively, and by 78% and 72% in dual culture bioassay against F. verticillioides. P. oligandrum progressed over the pathogen colony, suggesting a close type of interaction such as mycoparasitism, as confirmed by microscopic observation. In dual culture bioassay with F. graminearum, P. oligandrum reduced the growth and mycotoxin concentration by 79% and 93%, respectively. In the dual culture bioassay with F. verticillioides, P. oligandrum reduced the growth and mycotoxin concentration by 49% and 56%, respectively. In vitro dual culture bioassay with different culture media as well as the nutritional phenotyping of different microorganisms made it possible to explore the path of nutritional competition in order to explain part of the observed inhibition by BCAs.


Nematology ◽  
2005 ◽  
Vol 7 (1) ◽  
pp. 105-110 ◽  
Author(s):  
Patricia Timper ◽  
Roger N. Gates ◽  
Joe H. Bouton

Abstract The presence of the fungal endophyte Neotyphodium coenophialum in tall fescue (Festuca arundinacea) confers resistance to some plant-parasitic nematodes but also results in the production of ergot alkaloids. Recently, new strains of N. coenophialum have been isolated from wild tall fescue and artificially inoculated into elite tall fescue cultivars. These strains produce low to nil levels of ergot alkaloids and are referred to as non-ergot strains. Our objective was to determine whether non-ergot strains of the endophyte confer the same level of resistance to Pratylenchus spp. as the endemic strain in tall fescue. In a glasshouse experiment, nematode resistance was compared in two fescue cultivars (Jesup and Georgia 5) infected with either the endemic strain (E+), or two non-ergot strains, AR542 and AR584. An additional non-ergot strain, AR514, was tested only in cv. Jesup. Cultivars Georgia 5 and Jesup without endophytes (E−) were used as controls. The endophtye status of the plants was confirmed and then three plants per cultivar/endophyte combination were transplanted into 10 cm square pots. The pots were inoculated with a mixed culture of Pratylenchus zeae and P. scribneri in the first trial and a pure culture of P. scribneri in the second trial of the experiment. After 8 weeks, the number of nematodes within the roots from each pot was determined. Numbers of Pratylenchus spp. in either cv. Georgia 5 or cv. Jesup containing the non-ergot strain AR542 were not different from numbers in E− plants. AR514 also did not confer resistance to the nematodes in cv. Jesup. By contrast, the non-ergot strain AR584 appears to confer resistance to Pratylenchus spp. in cv. Georgia 5, but not in cv. Jesup; however, the level of resistance in cv. Georgia 5 was less than the resistance conferred by the endemic endophyte. Genetic differences between the two tall fescue cultivars may affect growth of the endophyte or production of a nematode toxin or deterrent by the endophyte. As only a small subset of endophyte strains has been tested, we are screening additional non-ergot strains for resistance to P. scribneri.


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