Antibacterial Inhibitory Activities Research Articles

Molecular Docking, Toxicity Study and Antimicrobial Assessment of Novel Synthesized 1,3-(Disubstituted)-thiazol-2-amines

In current study, a novel analogous of substituted-2-aminothiazoles (3a-o) were synthesized through a multi-step synthetic process. Structural elucidation of these newly synthesized substituted-2-aminothiazoles were achieved using combination of analytical techniques, comprising proton nuclear magnetic resonance (PNMR), mass spectrometry and FTIR. An in vitro investigation was performed to measure the efficacy of antibacterial and antimycotic characteristics of these novel compounds (3a-o). Specifically, the growth-inhibiting action against the test fungal strains, including A. niger, M. purpureos and A. flavus was examined. Additionally, their inhibitory antibacterial activity against key bacterial strains, including P. aeruginosa, S. aureus and E. coli was ascertained employing the agar diffusion technique. The results of antibacterial screening disclosed that maximum number of the thiazole derivatives viz. 3a, 3d, 3e, 3i, 3k, 3l and 3n displayed minimum inhibitory concentration of 12.5 µg/mL for E. coli. While compounds 3k and 3n displayed minimum inhibitory concentration of 12.5 µg/mL for S. aureus. A minimum inhibitory concentration of 25 µg/mL was exhibited by compounds 3i, 3l and 3n against P. aeruginosa. None of the 2-aminothiazole derivative disclosed promising action against the fungal strains. Screening for in silico ADME and toxicity studies revealed that compounds are fairly compatible and were devoid of potential toxicity except compounds 3j and 3m. The docking studies on DNA gyrase (PDB ID; 1KZN) shows favourable binding interaction comparable to the pre-occupied ligand clorobiocin.

Phytochemical Evaluation of Terminalia canescens DC. Radlk. Extracts with Antibacterial and Antibiotic Potentiation Activities against Selected β-Lactam Drug-Resistant Bacteria.

Terminalia canescens DC. Radlk. (family: Combretaceae) is native to northern Australia. Species of the genus Terminalia are widely used as traditional medicines to treat diverse ailments, including bacterial infections. However, we were unable to find any studies that had examined the antimicrobial activity of T. canescens. In this study, T. canescens was screened against a panel of bacterial pathogens, including multi-antibiotic-resistant strains. Solvents with different polarities were used to extract different complements of phytochemicals from T. canescens leaves. Methanolic and aqueous extracts exhibited substantial antimicrobial activity against various pathogens, including those that are multidrug-resistant strains. When combined with some selected clinical antibiotics, some extracts potentiated the antibacterial inhibitory activity. This study identified two synergistic, eleven additive, eleven non-interactive and eight antagonistic interactions. The toxicities of the plant extracts were examined in the Artemia franciscana nauplii assay and were found to be non-toxic, except the aqueous extract, which showed toxicity. Metabolomic liquid chromatography-mass spectrometry (LC-MS) analyses highlighted and identified several flavonoids, including vitexin, quercetin, orientin and kaempferol, as well as the tannins ellagic acid and pyrogallol, which may contribute to the antibacterial activities observed herein. The possible mechanism of action of these extracts was further explored in this study.

Phytofabrication of silver nanoparticles using callus extracts of natural tetraploid Trifolium pratense L. and its bioactivities

One of the main subjects of plant biotechnology is plant tissue culture and in recent years is considered a possible approach model for green and eco-friendly biosynthesis of nanoparticles. This study aimed to present calli produced from the natural tetraploid Trifolium pratense L. containing high amounts of phenolic compounds and glycosidic bioactive macromolecules and the biosynthesis of silver nanoparticles from calli. Combinatorial optimization of silver nanoparticles was achieved for the first time in this study, thanks to the stabilizing and reducing properties of hypocotyl, apical meristem, and epicotyl derived callus extracts of the natural tetraploid T. pratense L. biosynthesized nanoparticles from three different callus extracts. Callus extracts were used to create different experiments with AgNO3 at various concentrations (0.16, 0.5, 0.84, 1.18, 1.52 and 1.96 mg L-1), different temperatures (40, 50, 60, 70, 80, 90, 100°C), and different pH levels (5, 7, 10) to carry out the biosynthesis of AgNPs. Biologically synthesized AgNPs were easily monitored by color change in ultraviolet and UV-Vis spectroscopy proved to be a fast and simple method. Also, TEM, XRD, and FTIR analyses were done to characterize and confirm the formation of crystalline nanoparticles. It was determined that antibacterial activity inhibition was achieved by using the Agar-well diffusion method for antibacterial activity measurements on Gram-positive Staphylococcus aureus ATCC 25923 and Gram-negative Escherichia coli CECT 4972 bacteria. Biosynthesized AgNPs were observed in the wavelength range of 400-500 nm in the UV-VIS spectrum. TEM analysis demonstrated the size and shape of biosynthesized silver nanoparticles under different conditions. It was observed that the smaller silver nanoparticles were spherical and the larger silver nanoparticles were triangular, elliptical, and spherical shape. The XRD analysis proved the presence of Ag0 in nanoparticles and showed crystal structure for silver nanoparticles. By FTIR analysis, O-H hydroxyl groups of functional groups on the AgNP surface, H-linked OH stretching, C-H stretching, -CH stretching of -CH2 and -CH3 functional groups, C-N and carboxylate, aliphatic phosphate and primary amine stretching were expressed. Biosynthesized silver nanoparticles showed antibacterial activity against Gram-positive S. aureus ATCC 25923 bacteria, AgNP hypocotyl (1.7mm), AgNP-epicotyl (1.1mm) against Gram-negative E. coli CECT 4972 bacteria. Among the hypocotyl, apical meristem, and epicotyl callus cultures, the highest antioxidant activity was observed in the AgNPs obtained from hypocotyl-concentration experiments, with a DPPH radical activity of 52% and an ABTS radical activity of 68%. In conclusion, these findings underscore the potential of biotechnological strategies in green nanotechnology, which can be offered for developing metal nanoparticles with potential biomedicine and biotechnology applications.

Antibacterial Activity of Sea Leaf Extracts (Scaevola Taccada) Against Staphylococcus Aureus and Escherichia Coli

Scaevola taccada is one of coastal plants founded at Riau Island.. This research aims to determine the antibacterial activity of the crude extracts leaves of Scaevola taccada. this research was conducted in several stages including, sample preparation, extraction of leaves with maseration method, photochemical analysis and antibacterial activity test using the agar disc diffusion technique. The phytochemical results, crude leaves extract contained flavonoid, tannins, steroids, and saponins. The results of the antibacterial activity test showed that there was an inhibition of antibacterial activity on Staphylococcus aureus and Escherichia coli as indicated by the presence of a clear zone. Based on the results of the research, it was concluded that both ectract had antibacterial activity.

UJI AKTIVITAS ANTIBAKTERI EKSTRAK ETANOL DAUN NANGKA (Atrocarpus heterophyllus Lam) TERHADAP PERTUMBUHAN BAKTERI Staphylococcus aureus

Jackfruit leaves are one of the medical plants that have many benefits. In general, jackfruit leaves are known as animal feed, but behind their function as animal feed, jackfruit leaves have health benefits because jackfruit leaves contain antimicrobials including flavonoids, tannins, saponins that can dissolve in water and can work to damage cytoplasmic membranes and denature cell proteins bacteria. Staphylococcus aureus is a gram-positive bacterium and is arranged in clusters (like grapes). Some infectious diseases caused by these bacteria are impetigo, boils, acne, wound infections, toxic shock syndrome, and other types of pathogenic. This study was conducted to determine the effect of jackfruit leaf extract dissolved using 70% ethanol as a solvent on the growth of staphylococcus aureus bacteria. The method used is the maceration method for the phytochemical screening test, and the disc diffusion method for the antibacterial activity test. The results of the phytochemical screening contained secondary metabolite compounds in jackfruit leaves and for the results of the antibacterial activity test of jackfruit leaf ethanol extract against the growth of staphylococcus aureus bacteria there was antibacterial activity inhibition with high inhibition at 80% concentration with a diameter of 13mm.

Inhibition of Microencapsulated Liquid Smoke on the Foodborne Pathogens and Histamine-Forming Bacterias’ Growth in Tuna Loin Sashimi

Sashimi, a unique and simple fresh fish dish, is commonly served at a restaurant or as a family dinner in Japan. Because sashimi was created from fresh tuna loin, it is easily ruined by spoilage germs and pathogens, particularly when served without ice. Apart from ice, new preservatives must be investigated to avoid pathogenic and histamine-producing microorganisms. Liquid smoke (LS) contains antimicrobial chemicals including organic acids, carbonyl, and phenols from pyrolyzing coconut shells. However, because the evidence of physicochemical features of LS is scarce, research into liquid smoke microencapsulation is required. 
 The researchers wanted to figure out how liquid smoke microencapsulation (LSM) is made, how effective it is against harmful germs, and how much total histamine is present in LSM-coated sashimi maintained at room temperature. Histamine content, antibacterial inhibitory activity, total microbial count (TPC) of Salmonella and E. coli, water content, and pH level were tested. According to the findings, LSM with maltodextrin: sago flour: 1% LS ratio of 10: 1: 5 efficiently prevented E. coli and Salmonella development and reduced histamine level in sashimi refrigerated for 6 days in the refrigerator.

Utilization of Nanogold and Nanosilver in Kelor (Moringa Oleifera Lam.) Leaf Extract for Pandemic of Covid-19

This research has the purpose to determine the characteristics of the synthesis of 20 ppm nanogold using TEM, determine the effect of adding nanogold on the antioxidant activity of Moringa leaves, and determine the best concentration that supports increasing antioxidant activity in Moringa leaves. Nanogold and nanosilver were synthesized using bottom-up methods. The concentrations used for Moringa leaf extract and nanogold were 5, 10, 15, 20, 25, and 30 ppm. The concentration of the nanosilver used is 20 ppm. Nanosilver at a concentration of 20 ppm had the best inhibition of antibacterial activity. Testing of antioxidant activity was carried out using the DPPH method which was analyzed with a UV-Vis spectrophotometer. The results of the TEM nanogold test have a dominant cluster size of 22.17 nm. The best test results for the antioxidant activity of Moringa leaf extract at a concentration of 30 ppm was 60.7258 ppm. The addition of nanogold with a greater concentration of 30 ppm Moringa leaf extract resulted in greater antioxidant activity. The results showed that the best concentration of nanogold as a supporter of antioxidant activity in Moringa leaves was 30 ppm with a percent reduction of 79.288 ppm (very strong category).

Assessments of Antibacterial and Antioxidant Properties in the Methanolic and Aqueous Leaf Extracts of <i>Pistacia lentiscus</i> against Different Antibiotic Resistance Pathogenic Bacteria

The current study was carried out to determine the bioactivity of P. lentiscus leaf extracts as potential antibacterial and antioxidant properties. The plant extracts were examined for antibacterial activity against antibiotic-resistant Staphylococcus aureus, Staphylococcus haemolyticus, Pseudomonas aeruginosa, and Proteus mirabilis using the agar well method (according to the guidelines of Clinical and Laboratory Standard Institute). The antioxidant potential of 3 plant leaf extracts was determined by their ability to convert Fe3+ to Fe2+ and scavenge the DPPH free radical. At all concentrations studied, the methanolic leaf extract had higher total phenolic and flavonoid content, as well as stronger antioxidant and antibacterial inhibitory activity compared to aqueous extract. Our findings with P. aeruginosa were especially interesting, because this bacterium was inhibited by methanol extract than that of the reference antibiotics. The results also demonstrated a link between DPPH radical scavenging ability, reducing power, and total phenolic and flavonoid content of plant extracts (r > 0.97, R2 > 0.95, P = 0.01). As a result, the methanolic leaf extract of the chosen plant might be employed as an effective antioxidant and antibacterial agent for the treatment of a variety of morbidities.

Active Quinolinequinones against Methicillin-Resistant Staphylococcus spp.

Serious bacterial infections could be caused by Gram-positive microorganisms, in particular methicillin-resistant Staphylococcus aureus and Staphylococcus epidermidis. Aiming to address this challenging issue by developing the potent and selective antimicrobial lead structures against methicillin-resistant Staphylococcus spp., herein, we report in vitro evaluation of quinolinequinones (QQ1-QQ10) against the Gram-negative and Gram-positive strains using the broth microdilution technique. The design principle of the quinolinequinones was based on the variation of the structures attached to the 1,4-quinone moiety and substituent(s) within amino phenyl moiety. A series of ten quinolinequinones displayed activity mainly against the Gram-positive strains with a minimal inhibitory concentration (MIC=1.22-1250 mg/L) within the Clinical and Laboratory Standards Institute (CLSI) levels. Interestingly, QQ3, QQ5, and QQ6 displayed equal antibacterial inhibitory activity against S. aureus (MIC=1.22 mg/L), respectively, to the standard positive control Cefuroxime-Na. QQ2, QQ3, and QQ5 had the best inhibitory activity with the MIC value of 1.22 mg/L (4-fold more potent compared reference standard Cefuroxime) against S. epidermidis. On the other hand, QQ3 was the most effective quinolinequinone against fungi, in particular C. albicans. The identified lead quinolinequinones (QQ3 and QQ5) with a comprehensive analysis of structure-activity relationships and further studies showed high activity against methicillin-resistant Staphylococcus spp. It is worth noting that the isopropyl group has importance for excellent bioactivity. Remarkably, the in vitro antibiofilm and bactericidal activities (each of 32 clinically obtained strains of Gram-positive bacteria) of the selected two quinolinequinones (QQ3 and QQ5) have been evaluated for the mode of action in addition to the time-kill curve study.

Evaluation of Antimicrobial and Anticancer Activities of Selected Medicinal Plants of Himalayas, Pakistan.

Medicinal plants are known for their diverse use in the traditional medicine of the Himalayan region of Pakistan. The present study is designed to investigate the anticancer and antimicrobial activities of Prunus cornuta and Quercus semicarpifolia. The anticancer activity was performed using cancerous human cell lines (HepG2, Caco-2, A549, MDA-MB-231, and NCI-H1437 carcinoma cells), while the antimicrobial activity was conducted with the agar-well diffusion method. Furthermore, toxicity studies were performed on alveolar and renal primary epithelial cells. Initially, different extracts were prepared by maceration techniques using n-hexane, chloroform, ethyl acetate, butanol, and methanol. The preliminary phytochemical screening showed the presence of secondary metabolites such as alkaloids, tannins, saponins, flavonoids, glycosides, and quinones. The chloroform extract of P. cornuta (PCC) exhibited significant inhibitory activity against Acinetobacter baumannii (16 mm) and Salmonella enterica (14.5 mm). The A. baumannii and S. enterica strains appeared highly susceptible to n-hexane extract of P. cornuta (PCN) with an antibacterial effect of 15 mm and 15.5 mm, respectively. The results also showed that the methanolic extracts of Quercus semecarpifolia (QSM) exhibited considerable antibacterial inhibitory activity in A. baumannii (18 mm), Escherichia coli (15 mm). The QSN and QSE extracts also showed good inhibition in A. baumannii with a 16 mm zone of inhibition. The Rhizopus oryzae strain has shown remarkable mycelial inhibition by PCM and QSN with 16 mm and 21 mm inhibition, respectively. Furthermore, the extracts of P. cornuta and Q. semicarpifolia exhibited prominent growth inhibition of breast (MDA-MB-231) and lung (A549) carcinoma cells with 19–30% and 22–39% cell viabilities, respectively. The gut cell line survival was also significantly inhibited by Q. semicarpifolia (24–34%). The findings of this study provide valuable information for the future development of new antibacterial and anticancer medicinal agents from P. cornuta and Q. semicarpifolia extracts.

Imidazole added sulphamic acid single crystals with optimal properties for optoelectric devices

Single crystals of imidazole incorporated sulphamic acid (IMSA) of 12 × 7 × 7 mm3 dimension were successfully grown by slow evaporation technique. XRD study reveals that the grown crystal has the tetragonal structure. Various chemical groups formed in the sample have been found by FTIR spectral study. The linear optical parameters such as transmittance, reflectance, absorption coefficient, extinction coefficient, refractive index, optical conductivity and electrical conductivity of IMSA crystal have been analyzed Using UV–visible spectroscopy. Hardness studies reveal that the crystal shows reverse indentation size effect. An antibacterial activity developed by IMSA crystals against different pathogenic bacteria were examined using the Agar disk diffusion process. The antibacterial inhibitory activity of IMSA crystal revealed that it can be used to treat a variety of bacterial infections.

Extraction, Purification, Characterization and In Vitro Antibacterial properties of Sulfated Polysaccharide Extracted using Sargassum sp.

In the present study, Sulfated polysaccharides were extracted from macroalga Sargassum whitey collected from the Gulf of Mannar, Tamil Nadu, India. The maximum yield of 1.95g sulfated polysaccharide was extracted from Sargassum whitey and 0.81mg/ml of purified sulfated polysaccharide was obtained through DEAE anion exchange chromatography. The purified form was characterized using Fourier Transform Infrared Spectroscopy (FTIR), Energy Dispersive X-ray spectroscopy (EDX), and Field Emission Scanning Electron Microscopy (FESEM) analyses. The in vitro biological properties such as antibacterial, antioxidants activity (DPPH, Hydroxyl & Superoxide anion) of sulfated polysaccharides were evaluated and the results showed that 45μg mL-1 concentration of sulfated polysaccharide exhibited good antibacterial inhibitory activity against all the tested pathogenic bacteria strains, Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus. The in vitro antioxidant activity also found to be significant, where the exhibited IC50 concentrations by the purified sulfated polysaccharide was 183.2µg/mL for DPPH, 204.2µg/mL for superoxide anion, and 163.8µg/mL for Hydroxyl scavenge free radicals activities.

Evaluation of antioxidant activity of olive leaf extract obtained by ultrasound‐assisted extraction and their antimicrobial activity against bacterial pathogens from food

SummaryThe aim of the present study was to evaluate and compare the phenolic content and antioxidant and antimicrobial properties of olive leaf extracts obtained by ultrasound‐assisted extraction (UAE) and conventional extraction (CSE). UAE of olive leaf extracts yielded a higher total phenolic content (TPC) and total flavonoid content (TFC) of 14.31% and 19.50%, respectively. Higher antioxidant activities were found from the extracts prepared with UAE (for 18.5%, 12.5%, 10.9% and 17.6% higher determined by DPPH, ABTS, FRAP and CUPRAC methods, respectively). Good antibacterial inhibitory activity (as MIC and MBC) was observed against both Y. enterocolitica and S. aureus (1.40 ± 0.40 mg mL−1 and 4.00 ± 1.60 mg mL−1, respectively) with the extract prepared with UAE. In conclusion, olive leaf extracts prepared with UAE exhibited higher antioxidant and antimicrobial activities against common food‐borne pathogens than CSE extracts and thus could be beneficial in ensuring food quality and food safety.

Bioactive sulfonyl metabolites from the Red Sea endophytic fungus Penicillium aculeatum

Two new sulfonyl metabolites, pensulfonoxy (1) and pensulfonamide (2), together with four known metabolites were obtained from the fermentation extract of Penicillium aculeatum, an endophytic fungus isolated from the marine red alga Laurencia obtusa. The structures of the compounds were established on the basis of extensive NMR and MS spectroscopic analysis. The ethyl acetate extract exhibited potent antibacterial inhibitory activity against Escherichia coli, while compound 2 exhibited antifungal activity against Candida albicans with inhibition diameters of 20.5 and 18.0 mm, respectively. Moreover, compound 2 also displayed the most potent preferential cytotoxicity against MCF-7, while compound 1 displayed relatively mild activity against HCT-116 with IC50 values of 2.18 and 5.23 µM, respectively, compared to the drug control, paclitaxel.

Fabrication of green ZnO nanoparticles using walnut leaf extract to develop an antibacterial film based on polyethylene–starch–ZnO NPs

AbstractZinc oxide nanoparticles (ZnO NPs) were synthesized utilizing prepared walnut leaf extract by various amounts of its leaves (5–25 g) via a heater and stirrer adjusted at 60°C and reaction time ranging from 30 to 90 min. Fourier transform infrared spectroscopy and gas chromatography indicated the six main functional groups and 29 bioactive compounds in the provided walnut leaf extract. Antioxidant and antibacterial inhibitory activities of the fabricated ZnO NPs, in powder form, were modeled as a function of two synthesized parameters using response surface methodology, and the fabrication process was optimized. The results indicated that the ZnO NPs synthesized using walnut leaf extract, with 15.51 g of its dried powder and reaction time of 60 min, had maximum antioxidant activity and antibacterial effects againstEscherichia coli. X-ray diffraction analysis and scanning electron microscopy image indicated that the synthesized ZnO NPs using optimal processing conditions had crystals in triangular nanoprisms to nearly spherical shape with the particle size ranging from 15 to 40 nm. Finally, prepared biodegradable film composed of thermoplastic starch (5% w/w), polyethylene (93% w/w), and ZnO NPs (2% w/w) indicated high bactericidal inhibitory activity against both Gram-positive (Staphylococcus aureus) and Gram-negative (E. coli) bacterial strains.

Biosynthesis and characterization of nickel oxide nanoparticles by using aqueous grape extract and evaluation of their biological applications

This study involved the use of aqueous extract from grapes as reducing substance for the green synthesis of NiO nanoparticles (NiONPs). The morphology, crystalline structure and elementary composition were investigated through various characterisation methods, such as X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and UV–Visible spectroscopy, to demonstrate the synthesis of pure NiONPs. Strong anti-bacterial inhibitory activities of NiONPs have been examined by pathogenic bacterial strains studied against Gram-negative bacterial strain Klebsiella pneumoniae and Gram-positive bacterial strain Staphylococcus aureus. Potential cytotoxicity against human breast cancer (MCF-7) and human brain cancer (AMGM5) cell lines was shown by NiONPs. NiONPs have shown excellent biological applications. Moreover, NiO nanoparticles exhbibit toxicity to be safely used for different biomedical applications.

Studies on physicochemical and antibacterial deeds of amino acid based L-Threoninum sodium bromide.

Highly translucent nonlinear single crystals of L-Threoninum Sodium Bromide (LTSB) has been grown because of their rising need for everyday life and the XRD studies (PXRD and SXRD) solemnly affirmed the crystallinity and non-centrosymmetric space group of LTSB materials. The bonding nature and diverse functional groups in LTSB were demonstrated by FTIR analysis when they absorb infrared radiation. The optical behavior of LTSB crystals was explored through UV–Vis spectroscopy, which shows optical parameters depend on photon energy with band gap Eg = 5.7 eV which was suitable for optoelectronic devices. The electrical properties of LTSB crystals were measured by using dielectric measurement. The solid state parameters of LTSB crystal were calculated. An antibacterial activity developed by LTSB crystals against different pathogenic bacteria were examined using the Agar disk diffusion process. The antibacterial inhibitory activity of LTSB crystal revealed that it can be used to treat a variety of bacterial infections.

Proteomic analysis and antibacterial resistance mechanisms of Salmonella Enteritidis submitted to the inhibitory effect of Origanum vulgare essential oil, thymol and carvacrol

Biological properties of natural products are an important research target and essential oils (EO) from aromatic plants with antimicrobial properties are well documented. However, their uses are limited, and the mechanisms underlying their antibacterial activity are still not well known. Therefore, our objective was to evaluate the antibacterial activities of Origanum vulgare EO, thymol and carvacrol against Salmonella Enteritidis ATCC 13076 strain, particularly regarding the bacterial proteic profile, enzymatic activities and DNA synthesis. Bacterial expressed proteins were evaluated using an untreated assay control and treatments with sublethal concentrations of oregano EO, carvacrol and thymol. The same protein extracts were also assayed for oxidative stress and energy metabolism enzyme activities, as well as effect on DNA synthesis. Protein expression outcomes revealed by 2D-SDS-PAGE, from antimicrobial actions, showed a stress response with differential expressions of chaperones and cellular protein synthesis mediated by the bacterial signaling system. In addition, Salmonella used a similar mechanism in defense against oxidative stress, for its survival. Thus, the antibacterial inhibitory activity of EO was preferentially associated with the presence of thymol and there was interference in protein regulation as well as DNA synthesis affected by these compounds. SignificanceAntimicrobial activity of essential oils (EO) is already known. In this way, the understanding of how this activity occurs is a fundamental part to provide the practical and rational use of these substances. In the current scenario, where the emergence of resistant bacteria or even multiresistant bacteria against conventional antimicrobials, the search for alternatives becomes essential, since the discovery of new inhibitory substances does not occur at the same speed. The anti-Salmonella action allied to the knowledge about the biological processes affected by O. vulgare EO contribute to these bioactive compounds being effectively used as agents in the safety and shelf life of food in a future product, packaging or process where the antibacterial activity is safe and best used.

Penetapan Kadar Flavonoid Dan Uji Aktivitas Antibakteri Ekstrak Sereh (Cymbopogon nardus) Dan Temu Kunci (Boesnbergia pandurata Roxb) Terhadap Bakteri Streptococcus Mutans

Indonesia is rich in medicinal plants, including those that have the ability to inhibit bacterial growth, lemongrass (Cymbopogon nardus) and Fingerroots (Boesenbergia pandurata). Streptococcus mutans is a bacterium that causes dental caries. This Experiment want to determine the content of chemical compounds and the antibacterial activity of Lemongrass extract (Cymbopogon nardus) and Fingerroots (Boesenbergia pandurata) against Streptococcus mutans. The study was conducted experimentally with samples of lemongrass and Fingerroots. Extraction using maceration method using 70% Ethanol solvent. Phytochemical screening test with color test and determination of total flavonoid levels using a spectrophotometer. Antibacterial activity test uses the disk diffusion method against Streptococcus mutans. Phytochemical screening results of lemongrass extract and fingerroots with color test qualitative test showed positive containing flavonoids, saponins and tannins. In the test determination of total flavonoid levels, showed an average total flavonoid levels in lemongrass extracts of 48.61 mgQE / g and in Fingerroots extracts of 24.71 mgQE / g. The results of the antibacterial test against Streptococcus mutans obtained the largest average diameter of inhibitory zone in the extract of Fingerroots 5% w / v (11.167 mm), then the concentration of 5% w / v combination of lemongrass: Fingerroots 1: 2 (10.83 mm ), 2: 1 combination (10,067 mm). lemongrass (9.33 mm), 1: 1 combination (9,133 mm), Based on the Post Hoc test results that were comparable to positive controls were 5% fingerrots, combination of lemongrass: 1: 2 Fingerroots, and 2: 1 combination. The average total flavonoid level in lemongrass extract is more than the average total flavonoid content in Fingerroots. But in the same concentration 5% Fingerroots extract provides the greatest antibacterial inhibitory activities.

Novel Bioactive Penicipyrroether A and Pyrrospirone J from the Marine-Derived Penicillium sp. ZZ380.

The marine-sourced fungus Penicillium sp. ZZ380 was previously reported to have the ability to produce a series of new pyrrospirone alkaloids. Further investigation on this strain resulted in the isolation and identification of novel penicipyrroether A and pyrrospirone J. Each of them represents the first example of its structural type, with a unique 6/5/6/5 polycyclic fusion that is different from the 6/5/6/6 fused ring system for the reported pyrrospirones. Their structures were elucidated by extensive nuclear magnetic resonance (NMR) and high resolution electrospray ionization mass spectroscopy (HRESIMS) spectroscopic analyses, electronic circular dichroism (ECD) and 13C NMR calculations and X-ray single crystal diffraction. Penicipyrroether A showed potent antiproliferative activity against human glioma U87MG and U251 cells with half maximal inhibitory concentration (IC50) values of 1.64–5.50 μM and antibacterial inhibitory activity with minimum inhibitory concentration (MIC) values of 1.7 μg/mL against methicillin-resistant Staphylococcus aureus and 3.0 μg/mL against Escherichia coli.