PURIFIKASI SENYAWA POLIFENOL GLUKOSIDA HASIL REAKSI TRANSGLIKOSILASI ENZIMATIK DARI BIAKAN DAN UJI AKTIVITASNYA SEBAGAI ANTIMIKROBA

2016 ◽  
Vol 13 (2) ◽  
pp. 213 ◽  
Author(s):  
Rini Handayani ◽  
Rita Dwi Rahayu ◽  
Joko Sulistyo
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Transfer Reaction ◽  
Silica Matrix ◽  
Transfer Product ◽  
Authentic Standard ◽  
Nocardia Sp ◽  
Chromatography Plate ◽  
Layer Chromatography ◽  
Determine Effect

Polifenol-glukosida disintesis menggunakan CGTase yang berasal dari Nocardia sp. Sintesis polifenol-glukosida dilakukan dengan menggunakan resorsinol sebagai akseptor dan tepung sagu sebagai donor. Penelitian ini bertujuan untuk mensintesis senyawa polifenol-glukosida secara enzimatik menggunakan CGTase dari biakan Nocardia sp,menguji aktivitasnya sebagai senyawa antimikroba dan untuk mengetahui pengaruh senyawa polifenol-glukosida terhadap kerusakan morfologi sel dari biakan Bacillus subtilis. Polifenol–glukosida hasil reaksi transfer dimurnikan menggunakan kolom kromatografi yang berisi matriks oktadesil silica dan menggunakan eluen asam formatdalam methanol (40-90%). Produk yang sudah terpisah ditunjukkan sebagai noda tunggal pada plat kromatografi lapis tipis dengan nilai Rf mendekati nilai Rf standar arbutin. Nilai Rf dari produk transfer tersebut adalah sebesar 0,84 dan nilai Rf standar arbutin adalah sebesar 0.85. Polifenol-glukosida hasil sintesis menunjukkan aktivitasantimikroba terhadap biakan Bacillus subtilis dan Escherichia coli. Kata kunci : polifenol-glukosida, CGT-ase, Nocardia sp., Bacillus subtilis dan Escherichia coli AbstractPolyphenol-glucoside was synthesized by using CGTase derived from Nocardia sp. Synthesis polyphenol-glucoside of was done by using resorcinol as the acceptor and starch sago as the donor. This study aims to synthesized polyphenol-glucoside enzymatically using CGTase derived from Nocardia sp and to assay it’s activity as antimicrobial compound and to determine effect of polyphenol-glucoside on morphological damaging of Bacillus subtilis cells. The synthesized polyphenols-glucoside by transfer reaction was purified through column chromatography containing octadecyl silica matrix that was eluted with formic acid in methanol (40-90%). The separated product was demonstrated by single spot appearance on thin-layer chromatography plate with Rf value that was closed to standard of arbutin Rf. The Rf value of this transfer product was 0.84 while Rf value of arbutin as authentic standard was 0.85. The synthesized polyphenol-glucosie exhibited antimicrobial activity against Bacillus  subtilis and Escherichia coli. Key words : Polyphenol-glucoside, CGT-ase, Nocardia sp., Bacillus subtilis and  Escherichia coli.

scholarly journals Hydride transfer catalysed by Escherichia coli and Bacillus subtilis dihydrofolate reductase: coupled motions and distal mutations

2006 ◽  
Vol 361 (1472) ◽  
pp. 1365-1373 ◽  
Author(s):  
Sharon Hammes-Schiffer ◽  
James B Watney
Keyword(s):  
Escherichia Coli ◽  
Free Energy ◽  
Bacillus Subtilis ◽  
Dihydrofolate Reductase ◽  
Conformational Changes ◽  
Energy Barrier ◽  
Transfer Reaction ◽  
Hydride Transfer ◽  
Free Energy Barrier ◽  
Donor Acceptor

This paper reviews the results from hybrid quantum/classical molecular dynamics simulations of the hydride transfer reaction catalysed by wild-type (WT) and mutant Escherichia coli and WT Bacillus subtilis dihydrofolate reductase (DHFR). Nuclear quantum effects such as zero point energy and hydrogen tunnelling are significant in these reactions and substantially decrease the free energy barrier. The donor–acceptor distance decreases to ca 2.7 Å at transition-state configurations to enable the hydride transfer. A network of coupled motions representing conformational changes along the collective reaction coordinate facilitates the hydride transfer reaction by decreasing the donor–acceptor distance and providing a favourable geometric and electrostatic environment. Recent single-molecule experiments confirm that at least some of these thermally averaged equilibrium conformational changes occur on the millisecond time-scale of the hydride transfer. Distal mutations can lead to non-local structural changes and significantly impact the probability of sampling configurations conducive to the hydride transfer, thereby altering the free-energy barrier and the rate of hydride transfer. E. coli and B. subtilis DHFR enzymes, which have similar tertiary structures and hydride transfer rates with 44% sequence identity, exhibit both similarities and differences in the equilibrium motions and conformational changes correlated to hydride transfer, suggesting a balance of conservation and flexibility across species.

Antagonistic activity of Bacillus subtilis strains isolated from various sources

2018 ◽  
Vol 8 (2) ◽  
pp. 354-364
Author(s):  
A. N. Irkitova ◽  
A. V. Grebenshchikova ◽  
A. V. Matsyura
Keyword(s):  
Escherichia Coli ◽  
Bacillus Subtilis ◽  
Wild Strain ◽  
Fish Farming ◽  
Antagonistic Activity ◽  
Antagonistic Effect ◽  
E Coli ◽  
Long Period ◽  
Test Culture ◽  
Agar Media

<p>An important link in solving the problem of healthy food is the intensification of the livestock, poultry and fish farming, which is possible only in the adoption and rigorous implementation of the concept of rational feeding of animals. In the implementation of this concept required is the application of probiotic preparations. Currently, there is an increased interest in spore probiotics. In many ways, this can be explained by the fact that they use no vegetative forms of the bacilli and their spores. This property provides spore probiotics a number of advantages: they are not whimsical, easily could be selected, cultivated, and dried. Moreover, they are resistant to various factors and could remain viable during a long period. One of the most famous spore microorganisms, which are widely used in agriculture, is <em>Bacillus subtilis</em>. Among the requirements imposed to probiotic microorganisms is mandatory – antagonistic activity to pathogenic and conditional-pathogenic microflora. The article presents the results of the analysis of antagonistic activity of collection strains of <em>B. subtilis</em>, and strains isolated from commercial preparations. We studied the antagonistic activity on agar and liquid nutrient medias to trigger different antagonism mechanisms of <em>B. subtilis</em>. On agar media, we applied three diffusion methods: perpendicular bands, agar blocks, agar wells. We also applied the method of co-incubating the test culture (<em>Escherichia coli</em>) and the antagonist (or its supernatant) in the nutrient broth. Our results demonstrated that all our explored strains of <em>B. subtilis</em> have antimicrobial activity against a wild strain of <em>E. coli</em>, but to varying degrees. We identified strains of <em>B. subtilis</em> with the highest antagonistic effect that can be recommended for inclusion in microbial preparations for agriculture.</p><p><em><br /></em><em></em></p>

Synthesis of Chalcones and Nucleosides Incorporating [1, 3, 4]Oxadiazolenone Core and Evaluation of their Antifungal and Antibacterial Activities

2020 ◽  
Vol 15 (6) ◽  
pp. 665-679
Author(s):  
Alok K. Srivastava ◽  
Lokesh K. Pandey
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Antibacterial Activity ◽  
Bacillus Subtilis ◽  
Antifungal Activity ◽  
Aspergillus Niger ◽  
Gram Negative ◽  
E Coli ◽  
Gram Positive Bacteria ◽  
Good Antibacterial Activity

Background: [1, 3, 4]oxadiazolenone core containing chalcones and nucleosides were synthesized by Claisen-Schmidt condensation of a variety of benzaldehyde derivatives, obtained from oxidation of substituted 5-(3/6 substituted-4-Methylphenyl)-1, 3, 4-oxadiazole-2(3H)-one and various substituted acetophenone. The resultant chalcones were coupled with penta-O-acetylglucopyranose followed by deacetylation to get [1, 3, 4] oxadiazolenone core containing chalcones and nucleosides. Various analytical techniques viz IR, NMR, LC-MS and elemental analysis were used to confirm the structure of the synthesised compounds.The compounds were targeted against Bacillus subtilis, Staphylococcus aureus and Escherichia coli for antibacterial activity and Aspergillus flavus, Aspergillus niger and Fusarium oxysporum for antifungal activity. Methods: A mixture of Acid hydrazides (3.0 mmol) and N, Nʹ- carbonyl diimidazole (3.3 mmol) in 15 mL of dioxane was refluxed to afford substituted [1, 3, 4]-oxadiazole-2(3H)-one. The resulted [1, 3, 4]- oxadiazole-2(3H)-one (1.42 mmol) was oxidized with Chromyl chloride (1.5 mL) in 20 mL of carbon tetra chloride and condensed with acetophenones (1.42 mmol) to get chalcones 4. The equimolar ratio of obtained chalcones 4 and β -D-1,2,3,4,6- penta-O-acetylglucopyranose in presence of iodine was refluxed to get nucleosides 5. The [1, 3, 4] oxadiazolenone core containing chalcones 4 and nucleosides 5 were tested to determined minimum inhibitory concentration (MIC) value with the experimental procedure of Benson using disc-diffusion method. All compounds were tested at concentration of 5 mg/mL, 2.5 mg/mL, 1.25 mg/mL, 0.62 mg/mL, 0.31 mg/mL and 0.15 mg/mL for antifungal activity against three strains of pathogenic fungi Aspergillus flavus (A. flavus), Aspergillus niger (A. niger) and Fusarium oxysporum (F. oxysporum) and for antibacterial activity against Gram-negative bacterium: Escherichia coli (E. coli), and two Gram-positive bacteria: Staphylococcus aureus (S. aureus) and Bacillus subtilis(B. subtilis). Result: The chalcones 4 and nucleosides 5 were screened for antibacterial activity against E. coli, S. aureus and B. subtilis whereas antifungal activity against A. flavus, A. niger and F. oxysporum. Compounds 4a-t showed good antibacterial activity whereas compounds 5a-t containing glucose moiety showed better activity against fungi. The glucose moiety of compounds 5 helps to enter into the cell wall of fungi and control the cell growth. Conclusion: Chalcones 4 and nucleosides 5 incorporating [1, 3, 4] oxadiazolenone core were synthesized and characterized by various spectral techniques and elemental analysis. These compounds were evaluated for their antifungal activity against three fungi; viz. A. flavus, A. niger and F. oxysporum. In addition to this, synthesized compounds were evaluated for their antibacterial activity against gram negative bacteria E. Coli and gram positive bacteria S. aureus, B. subtilis. Compounds 4a-t showed good antibacterial activity whereas 5a-t showed better activity against fungi.

scholarly journals The use of Bacillus subtilis for screening fusaric acid production by Fusarium spp.

2009 ◽  
Vol 27 (No. 3) ◽  
pp. 203-209 ◽  
Author(s):  
A. Šrobárová ◽  
Š. Eged ◽  
J. Teixeira Da Silva ◽  
A. Ritieni ◽  
A. Santini
Keyword(s):  
Bacillus Subtilis ◽  
Secondary Metabolites ◽  
Thin Layer ◽  
Fusarium Oxysporum ◽  
Thin Layer Chromatography ◽  
Screening Test ◽  
Acid Production ◽  
Fusaric Acid ◽  
Modified Method ◽  
Layer Chromatography

Fusaric acid (FA) is one of the most important secondary metabolites produced by <I>Fusarium oxysporum</I> (Schlecht) (FO), <I>F. solani</I> (Mart.) Appel & Wollenweber, and <I>F. moniliforme</I> Sheldon. It is toxic to humans, many plants, and microorganisms and it enhances the toxicity of fumonisin and trichothecene. A simple and rapid method for fusaric acid (FA) screening in <I>Fusarium</I> isolates was developed. In this study, several strains of <I>Fusarium oxysporum</I> were tested for their ability to produce FA by using a suitable race of <I>Bacillus subtilis</I> as the bioassay. A modified method using small agar blocks with the fungus producing FA was applied in the screening test. FA standard and <I>F. culmorum</I> were used as controls. The experimental <I>F. oxysporum</I> isolates and FA standard produced transparent zones on the plates with <I>Bacillus subtilis</I>. The differences in size of the transparent zones corresponded to the quantity of FA when thin-layer chromatography was used.

scholarly journals Antioxidative, Antifungal and Additive Activity of the Antimicrobial Peptides Leg1 and Leg2 from Chickpea

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 585
Author(s):  
Marie-Louise Heymich ◽  
Laura Nißl ◽  
Dominik Hahn ◽  
Matthias Noll ◽  
Monika Pischetsrieder
Keyword(s):  
Escherichia Coli ◽  
Saccharomyces Cerevisiae ◽  
Ascorbic Acid ◽  
Bacillus Subtilis ◽  
Antifungal Activity ◽  
Antimicrobial Peptides ◽  
Antioxidative Activity ◽  
Radical Scavenging ◽  
Cytotoxic Effects ◽  
Zygosaccharomyces Bailii

The fight against food waste benefits from novel agents inhibiting spoilage. The present study investigated the preservative potential of the antimicrobial peptides Leg1 (RIKTVTSFDLPALRFLKL) and Leg2 (RIKTVTSFDLPALRWLKL) recently identified in chickpea legumin hydrolysates. Checkerboard assays revealed strong additive antimicrobial effects of Leg1/Leg2 with sodium benzoate against Escherichia coli and Bacillus subtilis with fractional inhibitory concentrations of 0.625 and 0.75. Additionally, Leg1/Leg2 displayed antifungal activity with minimum inhibitory concentrations of 500/250 µM against Saccharomyces cerevisiae and 250/125 µM against Zygosaccharomyces bailii. In contrast, no cytotoxic effects were observed against human Caco-2 cells at concentrations below 2000 µM (Leg1) and 1000 µM (Leg2). Particularly Leg2 showed antioxidative activity by radical scavenging and reducing mechanisms (maximally 91.5/86.3% compared to 91.2/94.7% for the control ascorbic acid). The present results demonstrate that Leg1/Leg2 have the potential to be applied as preservatives protecting food and other products against bacterial, fungal and oxidative spoilage.

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