Synergistic antibacterial activity of Phyllanthus emblica fruits and its phytocompounds with ampicillin: a computational and experimental study.

Phyllanthus emblica L. (syn. Emblica officinalis), popularly known as amla, Indian gooseberry, or the King of Rasyana, is a member of Phyllanthaceae family and is traditionally used in Ayurveda as an immunity booster. The present study aimed to investigate the synergistic interaction of Phyllanthus emblica (FPE) fruits and its selected phytocompounds with ampicillin against selected bacteria. Further, an in silico technique was used to find if major phytocompounds of FPE could bind to proteins responsible for antibiotic resistance in bacterial pathogens and enhance the bioactivity of ampicillin. FPE and all the selected phytocompounds were found to have synergistic antibacterial activity with ampicillin against tested bacteria in different combinations. However, ellagic acid and quercetin interactions with ampicillin resulted in maximum bioactivity enhancement of 32-128 folds and 16-277 folds, respectively. In silico analysis revealed strong ellagic acid, quercetin, and rutin binding with penicillin-binding protein (PBP-) 3, further supported by MD simulations. Ellagic acid and quercetin also fulfill Lipinski's rule, showing similar toxicity characteristics to ampicillin. FPE showed synergistic interaction with ampicillin, possibly due to the presence of phytocompounds such as gallic acid, ellagic acid, quercetin, and rutin. Molecular docking and MD simulations showed the strong interaction of ellagic acid and quercetin with PBP-3 protein. Therefore, these compounds can be explored as potential non-toxic drug candidates to combat bacterial antimicrobial resistance.

Bioassay-guided detection, identification and assessment of antibacterial and anti-inflammatory compounds from olive tree flower extracts by high-performance thin-layer chromatography linked to spectroscopy.

Olive trees are one of the most widely cultivated fruit trees in the world. The chemical compositions and biological activities of olive tree fruit and leaves have been extensively researched for their nutritional and health-promoting properties. In contrast, limited data have been reported on olive flowers. The present study aimed to analyse bioactive compounds in olive flower extracts and the effect of fermentation-assisted extraction on phenolic content and antioxidant activity. High-performance thin-layer chromatography (HPTLC) hyphenated with the bioassay-guided detection and spectroscopic identification of bioactive compounds was used for the analysis. Enzymatic and bacterial in situ bioassays were used to detect COX-1 enzyme inhibition and antibacterial activity. Multiple zones of antibacterial activity and one zone of COX-1 inhibition were detected in both, non-fermented and fermented, extracts. A newly developed HPTLC-based experimental protocol was used to measure the high-maximal inhibitory concentrations (IC50) for the assessment of the relative potency of the extracts in inhibiting COX-1 enzyme and antibacterial activity. Strong antibacterial activities detected in zones 4 and 7 were significantly higher in comparison to ampicillin, as confirmed by low IC50 values (IC50 = 57-58 µg in zone 4 and IC50 = 157-167 µg in zone 7) compared to the ampicillin IC50 value (IC50 = 495 µg). The COX-1 inhibition by the extract (IC50 = 76-98 µg) was also strong compared to that of salicylic acid (IC50 = 557 µg). By comparing the locations of the bands to coeluted standards, compounds from detected bioactive bands were tentatively identified. The eluates from bioactive HPTLC zones were further analysed by FTIR NMR, and LC-MS spectroscopy. Multiple zones of antibacterial activity were associated with the presence of triterpenoid acids, while COX-1 inhibition was related to the presence of long-chain fatty acids.

Synthesis and characterisation of gold nanoparticles from acacia leaf and to evaluate anticariogenic activity.

Objective: To synthesise the gold nanoparticles (AuNPs) using Acacia catechu through biogenic synthesis and evaluate their antimicrobial efficacy against S. mutans and E. coli in vitro. Methods: Green synthesised AuNPs were characterised using the ultraviolet-visible (UV-Vis) spectroscopy, and the size and shape of the synthesised nanoparticles were evaluated using the transmission electron microscopy (TEM). The antimicrobial efficacy of AuNPs (30/60/100 µl) against S. mutans/E. coli was evaluated on the Mueller-Hinton agar by measuring the zone of inhibition (ZOI) with ampicillin (15 µl) as a positive control. Results: The synthesised AuNPs were confirmed using the UV-Vis spectroscopy with peaks at 540 nm, and the size of the particle estimated using the TEM was between 5 and 15 nm. The antimicrobial efficacy of AuNPs was comparable to that of ampicillin against S. mutans/E. coli, but the difference was not significant. The antimicrobial effects increased in a dose-dependent fashion but were comparable across all concentrations and ampicillin. Conclusion: Green synthesised AuNPs exhibited significant antibacterial activity against S. mutans and E. coli at par with commercial ampicillin and demonstrated the potential towards anticariogenic agent for future use in dentistry.

O uso da talidomida como terapia adjuvante na leptospirose experimental / The use of thalidomide as adjuvant therapy in experimental leptospirosis

A leptospirose é uma zoonose de importância global, causada por leptospiras patogênicas. Seu tratamento é limitado quando iniciado após quatro dias do surgimento de sintomas, portanto, novas terapias adjuvantes são necessárias. Objetivo. Testar a droga imunomoduladora talidomida como terapia adjuvante à ampicilina no modelo de tratamento tardio da leptospirose experimental em hamsters. Métodos. 60 hamsters foram infectados via intraperitoneal por Leptospirainterrogans cepa L1-130, e foram separados em grupos: nenhum tratamento (NONE), talidomida (TAL), ampicilina (AMP) e ambos (AMP-TAL)...

Leptospirosis is a zoonosis of global importance, caused by pathogenic leptospira. His treatment is limited when started after four days of onset of symptoms, increasing the risk of morbidity and mortality, so new adjuvant therapies are needed.Objectives.To test the immunomodulatory drug, thalidomide, as an adjuvant therapy to antibiotics in experimental leptospirosis. Methods. Hamsters were infected by Leptospirainterrogans strain L1-130, and groups were assigned based on no treatment (NONE), thalidomide only (TAL), ampicillin only (AMP) or both (AMP-TAL). Thalidomide was administered via a gastric tube: 50 mg/kg in linseed oil and 2 ml/kg for three days. Ampicillin was administered intramuscularly at the rate of 100 mg/kg/bid for six days. Treatment was started two days after the onset of symptoms (experiment 1) and immediately after detection of the first death (experiment 2). Results. Experiment 1: all hamsters from the groups AMP and AMP-TAL...

Experimental determination of ampicillin adsorption to nanometer-size Al2O3 in water.

Transport of antibiotics in soil-water systems is controlled in part by adsorption to nanometer-size (10(-9)m) particles. Batch adsorption experiments were performed with ampicillin, a common amphoteric antibiotic, and 50 nm-Al(2)O(3) (alpha-alumina) at different pH conditions. Sorption to Al(2)O(3) can be described by linear isotherms for 2.9 microM-2.9 mM ampicillin concentrations. Distribution coefficients (K(d)) are 11.1 (+/-0.32)L kg(-1) at pH 2, 0.55 (+/-.04) L kg(-1) at pH 4, 21.9 (+/-0.9) L kg(-1) at pH 6, and 39.5 (+/-2.2) L kg(-1) at pH 8. At pH 2, approximately 47% of the initially adsorbed drug was removable by rinsing, at pH 4-56% was removed. Only 7% of the drug could be removed by rinsing at pH 6, and 3% at pH 8. Weak electrostatic forces dominate at pH<4, and stronger attachment mechanisms at higher pH. Low yields in rinsing (desorption) experiments at pH6 indicate strong attachment mechanisms, either electrostatic or possibly surface complexation.

The compatibility of nicardipine hydrochloride injection with various ICU medications during simulated Y-site injection.

Physical incompatibility studies between an intravenous calcium channel antagonist, nicardipine hydrochloride, and potentially coadministerable ICU medications have been performed. Forty-one medications and four solutions were evaluated. The medications were anesthetic/narcotics, antibiotics, an anticoagulant, a bronchodilator, electrolyte solutions, fluids, H2 receptor blocking agents, steroids and vasoactive agents. Of the forty-five substances, three showed evidence of physical incompatibility as manifested by turbidity, precipitation, or color change. All three were antibiotics. These were ampicillin, ampicillin/sulbactam sodium, and cefoperazone. We conclude that until bioavailability studies are performed these three antibiotics should not be coadministered with nicardipine HCl.

Antibiotics in acute cholecystitis.

In 460 cholecystectomies performed for acute cholecystitis 215 (47%) positive gallbladder bile cultures were obtained. In 73% of emergency operations bacteria were recovered, in 48% of early operations (p less than 0.001) and in 29% of late operations (p less than 0.001). In vitro concentrations of 8-16 mcg/ml of ampicillin or cephalothin inhibited in most cases the growth of E. coli, Klebsiella and Enterococci, which comprised 75% of all strains isolated. One hour after intravenous infusion of 1 g ampicillin the mean serum level was 21 mcg/ml, the mean common duct level 16 mcg/ml and the mean gallbladder bile level 4.4 mcg/ml. In acute cholecystitis 2 g cephalothin gave mean concentrations of 14, 8, and 1.2 mcg/ml. Most of these patients had cystic duct obstruction both on intravenous cholegraphy and during operation. Control patients with patent cystic ducts who received ampicillin had mean gallbladder and common duct bile levels of 47 and 56 mcg/ml, and those receiving cephalothin 23 and 28 mcg/ml. It appears that adequate gallbladder bile concentrations of antibiotics are not attainable in acute cholecystitis because of the obstruction to the bile flow. The favourable results of prophylactic antibiotic treatment in reducing septic complications seem to depend more on adequate serum and tissue concentrations than on the concentration of antibiotics in the bile.