Antibacterials - Science topic

Hello

The extraction was done by maceration method and kept at room temperature, but the antibacterial results were negative.

1. I need to immobilize microbes, how can I understand that hydroxyapatite chemical is antibacterial?

Although the material I used in the first week of my study showed an antibacterial effect, it did not show an antibacterial effect when I repeated the experiment 3 weeks later.

In antibacterial sensitivity assay, can a lower concentrations of a tested compound give a larger zone of inhibition than the larger concentrations of that compound?

As we all know using Cu, Ag, Ti etc given antibacterial properties. Is there any special metal which can give better then the above

Hi,

We need co-author for performing bio-imaging ( live cell imaging, cyto-toxicity, antibacterial, anti fungal activity study) study. If anybody interested please inbox me.

Hello al

Please i want to manually prepare antibiotic disk for disk diffusion method for an antibacterial plus enzyme inhibitor ( as amoxiclave for example)

My question is that how disk can be prepared? First mix the fractions then put on the disk or individually?

Thanks in advance

If the end application is antibacterial ,does the stabilizing agent used has any role to play?

Silver nanoparticles are prepared commercially in solid form, but i want to make the solution for antibacterial properties through MIC 96 well plates

Our goal is to encapsulate Essential Oil nanoparticles with antibacterial properties to make the application on textiles (fibers).

I would like to know how to interpretate the relationship between energy gap ∆E, calculated by DFT methods, and results of antibacteriel activity using disk diffusion methods of two compounds (comparative study)

I have synthesized Selenium nanoparticles using a plant source. After drying them in Petri plates , these nanoparticles were scraped out. Because of that some of them are found as large thin sheets. It was found to be difficult to reduce their size and also they are not properly suspended in distilled water for antibacterial studies. Is there any solution for these?

Mono- species biofilm such as E.faecalis

Dual - species biofilm such as E.faecalis & S.mutans

What is better for intracanal medicamments antibacterial experiment?

Although it is often said that plant- or mushroom-extracted compounds display their antibacterial activity through a dose-dependent manner, sometimes I observe that it is not practically always the case. Sometimes, an extract show potent antibacterial activity at lower doses, while it is ineffective at high doses. Any suggestion or postulation is welcome!

protein extraction for antibacterial activity

Which methods are best for determining the inhibition zone for bacteria? agar well diffusion method or disk diffusion methods.

I have got following results can you please tell me my result are fine or not if not what I should do to improve my result. Moreover, I haven't seen inhibition zone in that experiment. 10-6 I have got 160 colony calculated as 0.062 is it correct calculation??

There are so many antibacterial NPs available ranging from organic , inorganic to carbon and MXenes. I am planning to do an anti-biofilm study against oral polymicrobial biofilms. I am confused which nanoparticles should I choose from the available options.

I am trying to get the antibacterial activity of the fruit bark extracts. Please if you have any suggestion, kindly drop it.

I have performed antibacterial screening of new compounds (tried different combinations in different concentrations) against oral pathogens, and I got good activity against oral pathogens. Should I select these combinations with good antibacterial activity for my oral care gel formulation?

For Example.

compound A + compound B + compound C = 1ug/ml + 2ug/ml + 1ug/ml

The above combination gives a good antibacterial effect.

Can I consider this combination (with respective concentrations) for my oral care gel formulation?

I have prepared the silver nanoparticles via chemical reduction method using NaBH4. Upon turning yellow color of the solution I stopped the reaction. I got UV vis peak of nanoparticle solution at 400 nm.

But when I centrifuged the solution the pellet is so small that unable to use it for antibacterial activity. I want to ask whether I can use the AgNPs solution for MIC by diluting it with D.W. or pellet is necessary?

Also which medium will be suitable for the growth curve? either nutrient broth or PBS?

I will be grateful for your help.

Antibacterial activity was performed against gram positive and gram negative bacteria using 0.05M HCl as control. in gram positive bacteria control has not shown any significant activity whereas it has shown slight activity against gram negative bacteria . Pls suggest me how can i Calculate the % of inhibition in this case

The problem of antibacterial resistance to frequently

used antibiotics has led to a search for newer and

alternative compounds for the treatment of drugresistant

infections[1]. Although pharmaceutical

companies have designed a number of new antibiotics

in the last three decades, resistance against these drugs

by microorganisms has also been observed. Drug

resistant bacterial infections are causing immense

mortality and morbidity worldwide. For example, in

2005, in the United States, 19 000 out of 95 000 patients

affected from methicillin-resistant Staphylococcus

aureus (MRSA) have died. Number of death was

higher than number of deaths combined from HIV/

AIDS, Parkinson’s disease, emphysema, and homicides

combined[2]. As many branches of treatments like postsurgical

care, neonatal care, transplantation medicine,

cancer chemotherapy, and care of the critically ill

patients need effective antibiotic treatment, failure

of conventional antibiotic treatment to combat multidrug

resistant (MDR) pathogens, caused high rate

of mortality. With this background, World Health

Organization (WHO) identified MDR bacteria as one

of the top three high priority threats to human health.

Infectious Disease Society of America has addressed

the biomedical community to declare a war against the

MDR bacterial threat. Along with intensifying research

on understanding the resistance pattern of MDR

infection, they have stressed that the ultimate goal of

scientist would be to identify appropriate and efficient

antimicrobial drugs to the patients.

As for a long period of time, plants have been a

valuable source of natural products for maintaining

human health, certain plant extracts can be a cure

for infections caused by MDR. Along with different

herbs, seaweeds and higher plants, many workers have

suggested the usefulness of mangroves in traditional

medicines. Mangroves have been used as a source of

timber, food, fuel, fodder, medicines and fish poison in

tropical coastal zones. Recently scientists have found

evidence that mangroves have medicinal properties that

can cure many diseases like asthma, diabetes, cancer,

ulcer, wounds and AIDS.

In a broth microdilution antibacterial test, In some cases, I can observe the wells containing the tested bacteria mixed with a high concentration of the extract turn red after using TTC-based pectrophotometry, meaning the extract did not have any antibacterial activity. But in order to be accurate, I am wondering whether there are bacteria which are inhibited by the extract (and cannot grow anymore in the culture media) but are still metabolically active and thus they can reduce TTC to form formazon. How can I detect these types of bacteria?

Flowcytometry can be more accurate in that it can detect dead and viable bacterial cells. can it be more useful?

Best regards

Hamid

I performed a blend of essential oils against pathogens, in which I have chosen random combinations starting from respective MIC. One of these essential oils didn't show any effect against pathogens. Can I combine it with other essential oils with MIC values?

Dear sir

W-type Hexaferrite was written and published in chemical physics letters by me. In this article, I addressed the UV and antibacterial properties of Hexaferrite. However, due to band energy gab and antibacterial activity, I am unable to connect the two studies. That's why i'm asking this question. Thank you for interacting this question, Jamee M.Abduljalil and Roger Bayston.

Thank you very much.

Dear colleagues I have synthesized ZnO from Zn Plate using fiber laser using liquid laser ablation but it has shown no antibacterial activity

could anyone suggest how to solve such a problem?

Best Regards

how to make the disc of a particular nanoparticle concentration for antibacterial disc diffusion assay

I need CLSI guidelines for Riemerella anatipestifer infection in ducks.

In this investigate; the synthesis of cerium doped manganese ferrite (Mn1-xCexFe2O4) nanoparticle was carried outfacile Co-precipitation method. XRD, FTIR, FE-SEM, EDAX, VSM, XPS, and Antibacterial activities studied for synthesized materials. XRD reveals the cube structure after successful incorporation of Ce3+ ions in the Mn-ferrite matrix. FTIR studies confirmed spinel system ferrite. VSM exhibits enhanced magnetization of Ce3+ by MnFe2O4. XPS confirmed the cerium ions in all the doped samples and identified the chemical state of the ions in the ferrite material. Materials observed significant antibacterial activity at high cerium concentrations in manganese ferrite nanoparticles.

How can we know the ROS production when we treat bacterial cells with an antibiotic agent?

Disclaimer: I am not a microbiologist by profession or training and this is a curious/knowledge question

I have read some old articles that suggest the inoculum concentration to be 10^5 according to EUCAST.

I have also read some review articles suggesting 10^8 (0.5McFarland standard)- citing CLSI.

I am not able to download CLSI guidelines, can anyone help me get a copy to read about broth dilution and initial cell density actually prescribed?

Please let me know if these standards have changed? What cell concentration do researchers commonly use to read MIC (in North America or elsewhere)

I am struggling with the antibacterial activity trend of my hot-water extract (obtained from a mushroom). It inhibits the tested bacteria at very low concentrations but significantly stimulates the growth of the bacteria at high concentrations. This trend is the same with any bacterial species being tested. Can anyone please help me understand why this might happen?

E.coli shown 10.83% of growth inhibition% and s.aureus shown 11.23% at its lower concentration how to decide antibacterial quality .and in higher concentration (100)it is showing more inhibition.

What is the role of size and shape of nanoparticles in their antibacterial activity? What is the mechanism of antibacterial action of the nanoparticles? And how does it depend on the target organism?

Hi.

We have some carbon nanoparticles and want to check antibacterial activity against drug-resistant bacteria. Before working on drug-tolerant bacteria, Are there any protocols or parameters for checking nanoparticles whether have the antibacterial capability on drug-resistant bacteria?.

Hello,

I have a problem. My recombinant producted LL-37 form only alfa helix (CD spec.) and doesnt have antibacterial activity. Synthetic peptid LL-37 form random-coil (i see on CD spec.) and have antibacterial activity. Have you encountered anyone with this problem? How I transform alfa-helix to random-coil?

Thank you for answer,

Mr. Antonin Pavelka

Hi everyone

I am starting work on antibacterial activity from insects. Any help in protocols of preparation of Whole body extracts will be highly appreciated.

Thanks

I have performed the antibacterial tests under the presence of E.Coli and S.aurus bacteria. I did not observe any zone of inhibition.

I have gone through various literature some literature discussed the following statement.

"As material did not show antibacterial activity. Therefore this material is not toxic for useful bacteria and can be used for implant application.

However, other literature reveals

A zone of inhibition can be seen, which concludes the antibacterial activity of the material, and material can be used for implant applications.

Both statements are contradicting each other.

So I want to know that which statement is true?

Is implant material (Tibial component of Knee) need to perform the antibacterial activity?

I want to evaluate the antibacterial activity of metal nanoparticles at different time intervals. I am performing this experiment in a flask and after the specified time take out the sample for UV-vis. I am using PBS as growth media for bacteria. At 6 h the OD declines. What could be the possible reason of this? Also what should be the appropriate volume of the media?

Should the final gel needs visible or UV light to stimulate the TiO2 nanoparticles to work as antibacterial?

I'm intending to test the antibacterial activity of 2 medicinal plants from Comoros using disc diffusion assay. I wanted to used DMSO as negative control, however I've been told that it has some drawback and I should look for alternative. So what can I use instead of it?

I have prepared hydrogels , I want to determine antibacterial activity. Should I use them In gel form ? or I have also in solid dried powder form. What is the way of sample preparation form them ?

For plant extracts polymers and other I normally use 10mg/ml to 40mg/ml. The gels swell in water and DMSO.

The extraction of plant extracts exhibit pharmacological properties such as antibacterial, anticancer, antidiabetic, etc and the researchers use NMR, HPLC, GC-MS, and other testing methods to identify and purify the bioactive components that are responsible for this activity.

I'm curious about the rationale behind the synthesis of nanoparticles, such as silver or gold, using plants that have proven pharmacological properties.

I look forward to your explanation. Thanks.

i want fast publish free or low cost Scopus journal dealing with food antibacterial preservation

We have active antibacterial compounds and they are highly lipophilic. So we are using 10% kolliphor and 10% DMSO to solubilize them in micelles. When we test this formulation for MIC we don't see any activity. We have tried shaking the plates at 250rpm while incubating the mic plates and adding tween20 up to 30% to disrupt the micelles but have not been successful.

What is the best as chemicals what have antibacterial activity (like silver) for air treatment by tio2 photocatalyist to eliminate different types of bacteria and other air pollutants?

Please share the paper also ya. Thanks.

During screening of microbial extracts for antibacterial activity I keep seeing an unusual effect on the growth of P. aeruginosa (PA), which I hope you can see in the images attached. Basically I am doing disk diffusion assays, so plates are inoculated with bacterial solution matching 0.5 McFarland standard. Whenever I do this with PA I see what looks like viral plaques. I have tried preparing the inoculum using both the overnight growth and direct suspension methods, but still see the same effect. The same thing happens with two different strains of PA, and on two types of media (MHA and BHA). Interestingly, the technician in the lab has tried to replicate this several times without success.

Also, there seems to be a strange effect where there is a halo of these plaque looking things around some of the disks, yet the bacteria are growing within the zone.

If anyone has come across this before, or has any idea, I would love to hear from you!

antibacterial and antifungal activity Comparison between carboxymethylchitosan and quaternized chitosan

I did the hemolytic test, The result showing after 24 hours indicated that the bacteria have gamma-hemolytic (non-hemolytic), but I kept the plate in the incubator for 48 hours, then the clear halo zone showed around the colony (Beta-hemolytic). So which result should I use? I read some papers and normally they did incubation for around 16 -24 hours.

Another found was that 75-90% of my isolates from the fish gut have Alpha or Beta hemolytic. and almost 100% of my isolates with antibacterial activity are hemolytic strains. So I would like to ask two more questions:

1. Is hemolytic really a necessary safety test for probiotic due to many bacteria with hemolytic is available in the environment and we still can scope with them?

2. hemolytic activity and antibacterial activity are in correlated or not?

Thank you very much for your suggestion and comments!

for antibacterial activity, can we use other than standard isolates (as ATCC strains) for the purpose of knowing the effectiveness of certain herbs or any tested drug?

regards

I am working on depositing Polyaniline on titanium through electropolymerization using cyclic voltammeter for antibacterial effect. I found a couple of articles showing that they achieved antibacterial behavior by coating surfaces with Polyaniline. However, I am not able to achieve those results. I am able to form a film of Polyaniline (I assume that it is emaraldine because it is green in color) but my bacterial studies showed no antibacterial effect of the Polyaniline. Any ideas why or what should I do differently?

I am checking the antibacterial effect of synthesized molecules which is soluble in HFIP. Is there any effect of HFIP on bacterial growth.

is the so-called "sharp edge" a microscopic or macroscopic term? Any assembly or composite of molecules may form a "sharp edge". The real edge of GO is full of dangling bonds, functional groups, and structural defects. The reactivity is high at the edge. Of course, bacteria won't survive long enough. But the probability for a bacteria to stick on edge is relatively lower than on other sites/surfaces of the GO composites. The edge contribution may not be as significant as the authors have claimed. SBF induced HA appears to be "sharper" than any other components in the composites

I have some plant samples and I want to check the antiviral activity and Antibacterial Activity. and I want to check it by using bioinformatics.

So I need Suggestions regarding which bioinformatics parameter or software is available that I can use for check by antiviral and Antibacterial activity.

#bioinformatics #antiviral #antibacterial #plants

If we find synergism between two antibacterial drugs (phytochemical allicin + commercial antibiotics) in vitro then will it work in in vivo situation? What interfering factors might cause problems? What can be done to mitigate those challanges? Please provide some suitable literatures also.

Plant extract, activity, antibacterial, antifungal, enzyme inhibition

I have prepared zein/laponite coacervates of size ranges between 500-600 nm and I want to use it for further as a drug delivery carrier for antibacterial and in cancer cells. So can I use that much of size for these purpose? please help.

I performed the antibacterial activity of isolated herbal extract against Rhodococcus equi and used Erythromycin as a standard drug, ZOI of the plant extracts were 16-20mm and Erythromycin was 28 mm, are these herbal extracts are effective or not.

What is the criteria to consider any agent to consider as good/bad antibacterial.

I need to prepare a stock of 10 mg / ml erythromycin to check the mic value. I am trying to dissolve 0.1g/10 ml of water but i can't dissolve erythromycin in water.

How can i prepare 10 mg/ml stock solution? Do i need to use a solvent that does not have an antibacterial effect other than water?

I am working on a project for assessing the Antibacterial activity of various chemicals, I was wondering Can i make solution of those components using water as a solvent, depending on the fact that they can form hydrogen bond together which would make them together more likely soluble?

I am doing research to test antibacterial activity using plant leaves that I have mashed. How many ratio I should add between the simplicia and water to get 100% concentration in infusion technique?

I am currently working on cytotoxicity of bacterial extract, the extract is already known to have a antibacterial activity against Staphylococcus aureus from previous research. I am willing to know if both of those test (antibacterial and cytotoxicity) has any correlation ?

the extract itself only has Saponin as the secondary metabolite with simple phytochemical test.

For a first screening of antibiotic properties in a given substance, which bacterial strains (risk group 1) would you test to get a first general indication on whether the substance has a broad antibiotic spectrum?

I want to determine the antibacterial activity of Zinc Oxide nanoparticles by the disc diffusion method. In order to impregnate the disc with the appropriate concentration of ZnO, it has to be diluted (not dissolved) homogeneously. I have used methanol, DCM, and DMSO. I also used sonication and vortex shaking for the homogenization. Nevertheless, the ZnO did not show any antibacterial activity. Can anyone provide me a detailed SOP or procedure and suggest me a suitable solvent? Thanks in advance.

hello, here is the introduction of the Bacillus sp. i have been studying on:

1.it's Bacillus strain YB123 (haven't been identification).

2.it shows large inhibition zone with many phytobacterium.

3.it doesn't have any effect on plant immunity.

In so many literatures about antibacterial compounds from Bacillus spp., such as iturin, fengycin, surfactin,

they said that the supernatant was work on plate assay, and shows visible inhibition zone,

but i really can't understand why the supernatant of YB123 doesn't show any about that?

Are there any literature of antibacterial compound mentioned the compounds only secreted while the bacteria was present?

THANKS FOR YOUR HELP!!

I want to check antibacterial activity of CaCO3 nanoparticles, and I have to make suspension in which they can easily disperse. I have tried DMSO, chloroform, ethanol, saline and DI water, but unable to do so.

If you have a technical question about antimicrobial research, there is a resource called REVIVE.

https://revive.gardp.org/talk-to-an-expert/

"REVIVE is working with leading experts in the field of antimicrobial R&D who are committed to support scientists from across the world in advancing their research. With this interface we want to help you to get in touch with these experts and to give you the opportunity to discuss your research questions with them."

see also this paper: https://academic.oup.com/jac/article/74/7/1769/5359493

REVIVE is a project of The Global Antibiotic Research & Development Partnership (GARDP). From the above paper:

"The Global Antibiotic Research & Development Partnership (GARDP; https://www.gardp.org) is a not-for-profit research and development (R&D) organization that addresses global public health needs by developing and delivering new or improved antibiotic treatments, while endeavouring to ensure that access to them is sustainable. Initiated by the WHO and the Drugs for Neglected Diseases initiative (DNDi), GARDP is an important element of the WHO’s Global Action Plan on Antimicrobial Resistance, which calls for new public–private partnerships to encourage research and development of new antimicrobial agents and diagnostics."

Hey my dear freinds,

I wonder how to modify the known antibacterial peptides’ amino acids composition to make them more easily bond to both gram- positive and negative bacteria, which kinds of aa replaced could enhance this ability ?

Dear all,

I am looking for publications dealing with the long-term stability of antibacterial coatings. I need to know if the coating still works even after months or years. The latest term I found was 56 days which is not sufficient long for my research.

Thank you in advance.

please suggest me the method to determine the antibacterial activity of silver nanoparticles with full of procedure or refer me any research paper.

thanks and best regards

I have a polymer which have antibacterial effect, I need a full, clear procedure to do in order to test the polymer effect into bacterial (E.coli and staphyloccucs aureos)?

Note: The polymer has already fabricated.

What is the best method to fix the extract of herbs onto cotton fabrics to impart them durable antibacterial properties, color and aroma?

It is known that fixation at high temperature for such substances may lead to lose of their characteristics. Also use of some chemicals is also not favorable.

We want to study the antimicrobial potential of medicinal plant extracts. Kindly suggest the precautions for antibacterial and antifungal activities.

what i observed in lab is that cellulose nanofibers are not antibacterial against s. aureus

types of antibacterial and anti fungal can you gives ?

Hello,

I am curious, do someone has the experiences with the the bacterial colonies aggregation (on the pictures), especially of B. subitlis, nearly behind or on the edge of inhibition (or rather no-growing) zone within Kirby-Bauer disc diffusion tests? And can I consider this phenomenon as the proof of the antibacterial activity of extracts 3, 4 and 5 or it has some other explanation, e.g. just some weak intolerance/sensitivity of bacterial strain for the metabolites followed by the transfer of highly mobile cells of B. subtilis to "non-toxic" zone? Thank you very much for each prospective reaction.

Hint for the pic.:

bacterial lawn - Bacillus subtilis culture inoculated from the liquid media Tryptic Soy Broth containing endospores of B. subtilis

samples on discs - 1,3,4,5,6 - different extracts of secondary metabolites from Streptomyces (after Ethyl acetate extraction, dissolved in methanol), 2 - Ethyl acetate control