Pseudomonas Lipopeptide-Mediated Biocontrol: Chemotaxonomy and Biological Activity

Pseudomonas lipopeptides (Ps-LPs) play crucial roles in bacterial physiology, host–microbe interactions and plant disease control. Beneficial LP producers have mainly been isolated from the rhizosphere, phyllosphere and from bulk soils. Despite their wide geographic distribution and host range, emerging evidence suggests that LP-producing pseudomonads and their corresponding molecules display tight specificity and follow a phylogenetic distribution. About a decade ago, biocontrol LPs were mainly reported from the P. fluorescens group, but this has drastically advanced due to increased LP diversity research. On the one hand, the presence of a close-knit relationship between Pseudomonas taxonomy and the molecule produced may provide a startup toolbox for the delineation of unknown LPs into existing (or novel) LP groups. Furthermore, a taxonomy–molecule match may facilitate decisions regarding antimicrobial activity profiling and subsequent agricultural relevance of such LPs. In this review, we highlight and discuss the production of beneficial Ps-LPs by strains situated within unique taxonomic groups and the lineage-specificity and coevolution of this relationship. We also chronicle the antimicrobial activity demonstrated by these biomolecules in limited plant systems compared with multiple in vitro assays. Our review further stresses the need to systematically elucidate the roles of diverse Ps-LP groups in direct plant–pathogen interactions and in the enhancement of plant innate immunity.

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Curcumin: Natural Antimicrobial and Anti Inflammatory Agent

Journal of Pharmaceutical Research International ◽

10.9734/jpri/2020/v32i4331060 ◽

2021 ◽

pp. 1-8

Author(s):

Pehlivanović Belma ◽

Čaklovica Kenan ◽

Lagumdžija Dina ◽

Omerović Naida ◽

Žiga Smajić Nermina ◽

...

Keyword(s):

Antimicrobial Activity ◽

Protein Denaturation ◽

Dose Range ◽

In Vitro Assays ◽

Natural Antimicrobial ◽

In Vivo Models ◽

Vitro Assay ◽

Inflammatory Agent ◽

Anti Inflammatory

The pursuance of novel antimicrobial and anti-inflammatory agents has been expanding due to a significant need for more efficient pharmacotherapy of various infections and chronic diseases. During the last decade, pharmacokinetics, pharmacodynamics and pharmacological properties of curcumin have been extensively studied. The aim of the present study was to evaluate the antibacterial activity of curcumin against both Gram-positive and Gram-negative bacteria as well as its antifungal activity by using in vitro agar well diffusion assay. Moreover, the anti-inflammatory activity of curcumin was determined with in vitro assay of inhibition of protein denaturation. Results demonstrated wide antimicrobial activity of curcumin upon all of the test bacteria and fungi. The strongest activity of curcumin was observed at a concentration of 0.50 mg/ml against S. aureus, L. monocytogenes, E. coli, P. aeruginosa and C. albicans, resulting in a maximum zone of inhibition of 14.7 mm, 14.3 mm, 13.7 mm, 10.7 mm and 10.7 mm, respectively. Findings suggested that the antimicrobial activity of curcuminis dependent upon the concentrations. Furthermore, results demonstrated high effectiveness of curcumin compared to standard acetylsalicylic acid in inhibiting heat-induced protein denaturation, which activity is also depended upon the concentrations. The present study emphasises the potential application of curcumin as a natural antimicrobial and anti-inflammatory agent. However, findings of this study are restricted to in vitro assays and consideration should be given to conducting a study involving wider dose range test substances as well as including further research on in vivo models.

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PTSA-Catalyzed One Pot Domino Synthesis of Dihydropyrido[2,3-d]pyrimidine Derivatives and their Antimicrobial Activity

Asian Journal of Organic & Medicinal Chemistry ◽

10.14233/ajomc.2021.ajomc-p340 ◽

2021 ◽

Vol 6 (3) ◽

pp. 222-227

Author(s):

Krishna A. Bhensdadia ◽

Prakash L. Kalavadiya ◽

Nilam H. Lalavani ◽

Shipra H. Baluja

Keyword(s):

Antimicrobial Activity ◽

Spectral Analysis ◽

Pyrimidine Derivatives ◽

One Pot ◽

In Vitro Antimicrobial Activity ◽

Aryl Aldehydes ◽

Three Component Reaction ◽

The One

A novel series of dihydropyrido[2,3-d]pyrimidine derivatives were synthesized by multicomponent domino cyclization via the one-pot three component reaction of 6-amino uracil, substituted aryl aldehydes and N-methyl-1-(methylthio)-2-nitroethenamine in the presence of PTSA 10 mol% as a catalyst. The structures of these synthesized compounds were characterized by spectral analysis. Further the synthesized compounds screened for in vitro antimicrobial activity. Among all the compounds, compound 4b containing flouro substitution exhibited good inhibition against the tested species.

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Microwave Assisted One Pot Synthesis of Tetrazole Based 3-hydroxy-4H-chromen-4-ones by modified Algar-Flynn-Oyamada reaction and their Antimicrobial activity

Journal of the Mexican Chemical Society ◽

10.29356/jmcs.v63i4.448 ◽

2019 ◽

Vol 63 (4) ◽

Author(s):

ASHOK DONGAMANTI ◽

Nagaraju Nalaparaju ◽

Sarasija Madderla ◽

Vijaya Lakshmi Bommidi

Keyword(s):

Escherichia Coli ◽

Antimicrobial Activity ◽

Klebsiella Pneumonia ◽

Good Activity ◽

One Pot ◽

Microwave Assisted ◽

One Pot Synthesis ◽

Antimicrobial Studies ◽

The One

In the present work, we report the one pot synthesis of tetrazole based 3-hydroxy-4H-chromen-4-ones 3(a-g) from 4-(1H-tetrazol-5-yl)benzaldehyde and 2-hydroxy acetophenone using KOH and H2O2 by modified Algar-Flynn-Oyamada reaction under conventional and microwave irradiation conditions. In this technique, flavonols are synthesized without isolating chalcones, in good yields. All the synthesized compounds were characterized by IR, NMR, MS and elemental. All newly synthesized compounds were screened for their in-vitro antimicrobial activity against strains such as Staphylococcus aurous, Bacillus subtilis, Klebsiella pneumonia, Escherichia coli, Aspergillus Niger, Aspergillus flavus, and Fusarium oxysporum. The results of antimicrobial studies revealed that most of the compounds exhibit good activity.

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Pomegranate Byproduct Extracts as Ingredients for Producing Experimental Cheese with Enhanced Microbiological, Functional, and Physical Characteristics

Foods ◽

10.3390/foods10112669 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2669

Author(s):

Lucia Parafati ◽

Fabiola Pesce ◽

Laura Siracusa ◽

Biagio Fallico ◽

Cristina Restuccia ◽

...

Keyword(s):

Antimicrobial Activity ◽

Food Poisoning ◽

Raw Milk ◽

In Vitro Assays ◽

Polyphenol Content ◽

Pomegranate Peel ◽

Food Preservatives ◽

Physico Chemical ◽

Antimicrobial And Antioxidant Activity

Pomegranate peel and mesocarp, considered as wastes of fruit processing, are rich sources of beneficial phytochemicals, including hydrolyzable tannins and flavonoids, with proven antimicrobial and antioxidant activity, which can be employed for improving the overall quality of food products. In the present study, extracts from pomegranate peel (PPW) and mesocarp (PMW) were obtained through a water extraction method and evaluated for in vitro antimicrobial activity and polyphenol content. The two extracts were then added during the cheese-making process in order to create a new functional cheese with improved microbiological and physico-chemical characteristics. Antimicrobial in vitro assays evidenced a substantial efficacy of both extracts against Staphylococcus aureus, which often causes staphylococcal food poisoning outbreaks linked to the consumption of raw milk cheeses and artisanal cheeses. For this reason, a simulated cheese contamination was carried out in order to assess if pomegranate extracts can exert antimicrobial activity towards this pathogen even when incorporated into the cheese matrix. Milk enriched with pomegranate extracts (PPW and PMW) was used to produce two different experimental cheeses, which were then evaluated for yield, polyphenol content, and microbiological as well as physico-chemical traits throughout the refrigerated storage. Despite the low concentration of the extracts, the treated cheeses showed an increase in firmness and a slight decrease in S. aureus counts, of more than one log unit in comparison to the control cheese, for up to 12 d of cold storage. Such results support the reuse of agro-food byproducts, in substitution to chemical food preservatives, as the key to a circular economy.

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In Vivo Recovery of Factor VIII: A Comparison of One-Stage and Two-Stage Assay Methods

Thrombosis and Haemostasis ◽

10.1055/s-0038-1657018 ◽

1979 ◽

Vol 42 (04) ◽

pp. 1230-1239 ◽

Cited By ~ 46

Author(s):

I M Nilsson ◽

T B L Kirkwood ◽

T W Barrowcliffe

Keyword(s):

Factor Viii ◽

Half Life ◽

In Vitro Assays ◽

Two Stage ◽

One Stage ◽

Significant Difference ◽

Assay Methods ◽

The One ◽

Fraction I

SummaryThe recovery and half-life of VIII: C in the plasma of severely haemophilic patients was measured by one-stage and two-stage assays after injection of two Factor VIII concentrates (Hemofil, Hyland and Fraction I-O, Kabi). Plasma volumes were measured with an Evans� Blue technique, and both concentrates and post-infusion samples were measured against the same plasma standard.There was a highly significant difference in recoveries estimated by the two assay methods. The one-stage assays gave the most consistent results, in that the average recovery was 100%, whereas the two-stage assays gave only about 80% of the value expected from in vitro assays. There was no difference in recoveries between the two concentrates.The two-stage assays gave a slightly shorter half-life than the one-stage assays, and the half-life of Hemofil was also shorter than that of Fraction I-O.

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Resolving host–microbe interactions in the gut: the promise of in vitro models to complement in vivo research

Current Opinion in Microbiology ◽

10.1016/j.mib.2018.07.001 ◽

2018 ◽

Vol 44 ◽

pp. 28-33 ◽

Cited By ~ 8

Author(s):

Wilmes Paul ◽

Calatayud Marta ◽

Van de Wiele Tom

Keyword(s):

In Vitro Models ◽

Microbe Interactions ◽

Host Microbe Interactions

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Decreased Potency Of Factor VIII Concentrates

10.1055/s-0038-1652637 ◽

1981 ◽

Cited By ~ 3

Author(s):

C K Kasper

Keyword(s):

Factor Viii ◽

In Vitro Assays ◽

Assay Method ◽

Two Stage ◽

One Stage ◽

Plasma Factor ◽

Factor Viii Concentrates ◽

The One

Plasma factor VIII recoveries after infusions of factor VIII concentrates into patients with classic hemophilia have been measured in this laboratory for 14 years. Recently, we observed a decline in the in vivo recovery of factor VIII per factor VIII unit infused. In 1980, plasma factor VIII levels were measured by a one-stage APTT-based assay before and 10 min after 150 infusions of 46 lots of 3 brands of factor VIII concentrate produced in the U.S.A. Our pooled normal plasma reference was calibrated against WHO International Standard 2 and results expressed in International factor VIII units. Observed in vivo factor VIII recovery was compared to the value expected from calculations based on the unitage stated on the label. The ratio of observed/expected recovery averaged 56% per lot for brand A, 60% per lot for brand B, and 103% per lot for brand C. In vitro assays were performed on 22 lots on 36 occasions, and the ratio of observed/labelled units average 46% per lot for brand A, 53% for brand B and 75% for brand C. The two-stage factor VIII assay method of Pool and Robinson was also used to assay plasma samples from 18 infusions, and results averaged 135% of the one-stage values for infusions of brand A, 160% for brand B, and 109% for brand C. (Brand A is assayed by the manufacturer by a two-stage method, brands B and C by one-stage methods.)Decreased clinical efficacy was observed when postinfusion plasma factor VIII levels were lower than customary. The decline in potency of brands A and B has necessitated more frequent assay of patients and use of larger amounts of concentrate, with greatly-increased expense. Investigation of the effect of different assay methods and different factor VIII standards and references on the apparent factor VIII content of concentrates has begun.

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Development of an in vitro coculture device for the investigation of host–microbe interactions via integrative multiomics approaches

Biotechnology and Bioengineering ◽

10.1002/bit.27676 ◽

2021 ◽

Author(s):

Won‐Suk Song ◽

Sung Gyu Shin ◽

Sung‐Hyun Jo ◽

Jae‐Seung Lee ◽

Hyo‐Jin Jeon ◽

...

Keyword(s):

Microbe Interactions ◽

Host Microbe Interactions

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In vitro Assessment of Bacterial Strains Associated with Microalgae as Potential Probiotics

Pertanika Journal of Tropical Agricultural Science ◽

10.47836/pjtas.44.1.12 ◽

2021 ◽

Vol 44 (1) ◽

Author(s):

Aimi Zabidi ◽

Natasya-Ain Rosland ◽

Jasmin Yaminudin ◽

Murni Karim

Keyword(s):

Antimicrobial Activity ◽

In Vitro Assays ◽

Disc Diffusion ◽

Bacterial Strains ◽

Pathogenic Vibrio ◽

Fish And Shellfish ◽

Diffusion Assay ◽

Vibrio Spp

Bacteria and microalgae are essential elements in the aquatic ecosystem, co-existing and having constant interactions with each other which help microalgae to exert its beneficial effect as probiotics in aquaculture. This research aims to isolate and identify potential probiotics from different species of microalgae and to evaluate their antimicrobial activity against pathogenic Vibrio spp. via series of in vitro assays; disc diffusion, well diffusion, and co-culture assays. A total of 18 bacterial strains were isolated from five species of microalgae; Chlorella sp., Nannochloropsis sp., Amphora sp., Chaetoceros sp., and Spirulina sp.. The isolated strains were tested in in vitro antagonistic assay against four Vibrio spp. (Vibrio harveyi, Vibrio alginolyticus, Vibrio vulnificus, and Vibrio parahaemolyticus). Seventeen strains demonstrated antimicrobial activity with the highest inhibition was observed by strain SPS11 against V. parahaemolyticus (12.6 ± 0.36 mm) in disc diffusion assay and strain NAS32 showed 13.2 ± 0.45 mm clear zone against V. vulnificus in well diffusion assay. In co-culture assay, both the SPS11 and NAS32 were able to reduce the growth of V. parahaemolyticus and V. harveyi at concentration of 106 and 108 CFU mL-1, respectively. Strains SPS11 and NAS32 were characterized as gram positive bacteria with rod shape and further identified as Lysinibacillus fusiformis (SPS11) and Lysinibacillus sphaericus (NAS32) using 16s rRNA. These two strains should be further studied in in vivo challenged experiments in fish and shellfish to explore their probiotic effects.

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