In vitro and in vivo efficacy of methyl oleate and palmitic acid against ESBL producing MDR Escherichia coli and Klebsiella pneumoniae.

PURPOSE: Antibiotic resistance is a huge problem that stays to challenge the healthcare sector in a large part of the world in both developing and developed countries. The spread of multi drug resistant (MDR) bacteria in hospital and community settings remains a widely uncertain problem and a heavy burden to health services. METHODS: This study unveils the in vitro and in vivo anti-ESBL potential of Methyl oleate (MO) and Palmitic acid (PA) against ESBL producing MDR bacterial pathogens such as Escherichia coli and Klebsiella pneumoniae. Microscopic observations unveiled the anti-ESBL efficacy of test compounds. MTT assay, in vivo anti-infective efficiency of MO and PA was tested with different concentrations. RESULTS: The pure compounds of MO and PA from Oxynema thaianum demonstrated high inhibitory activity in MIC and MBC assays against MDR E. coli and K. pneumoniae. Moreover, the anti-ESBL potential of MO and PA was validated through light, confocal laser scanning and scanning electron microscopic analyses. The IC50 values of MO and PA against A549 cells was recorded as 625 µg mL-1 and 514 µg mL-1, respectively. In Artemia nauplii cytotoxicity assay, the LC50 value of MO and PA were recorded as 53.33 µg mL-1 and 50 µg mL-1 respectively. The 96 h lethal concentrations obtained for Lobeo rohita treated with different concentrations of Methyl oleate and Palmitic acid. The LC50 for MO and PA was 50 mg L-1 and 100 mg L-1, respectively. CONCLUSION: Therefore the study concluded that the promising effects of MO and PA can be used as an alternative biological agent which could be positively explored to treat ESBL producing MDR pathogens.

Isolation and structural characterization of sulfated polysaccharide from Spirulina platensis and its bioactive potential: In vitro antioxidant, antibacterial activity and Zebrafish growth and reproductive performance.

In this study, the sulfated polysaccharide (SPs) was isolated from Spirulina platensis. The isolated SPs contains carbohydrate, sulfate, protein and uronic acid at 38.7 ±â€¯0.30%, 21.3 ±â€¯0.87%, 7.1 ±â€¯0.15% and 7.9 ±â€¯0.4% respectively. The elemental analysis confirmed the presence of carbon (18.01 ±â€¯0.10%), hydrogen (1.83 ±â€¯0.02%) and nitrogen (3.43 ±â€¯0.01%). The monosaccharide composition and molecular weight of SPs were analyzed by high-performance liquid chromatography and size exclusion chromatography respectively. The monosaccharide composition analysis showed the existence of glucose, rhamnose, xylose, fucose, mannose, galactose and the molecular weight of SPs was 1016 kDa. Further, the characterization of SPs was done by UV-visible spectroscopy, X-ray diffraction, FT-IR, 1H NMR and 13C NMR analysis. The obtained SPs exhibited potent antioxidant activity in DPPH (76.45 ±â€¯0.49%), reducing power (absorbance: 1.3 ±â€¯0.02), hydrogen peroxide scavenging (66.3 ±â€¯1.16%), hydroxyl scavenging (68.6 ±â€¯3.2%), nitric oxide (81.36 ±â€¯1.85%) and total antioxidant (absorbance:1.66 ±â€¯0.02) activities at 5 mg/ml. In addition, SPs revealed the highest antibacterial efficacy against the pathogenic bacteria Vibrio vulnificus in disc diffusion, agar bioassay and protein leakage assays at 100 µg/ml. Furthermore, the supplementation of 2% SPs through a feed to the Danio rerio fish enhances the growth and reproductive performances. This finding confirmed that the isolated SPs from S. platensis possess pharmaceutical as well as nutritional properties.

Antibacterial efficacy of a fucoidan fraction (Fu-F2) extracted from Sargassum polycystum.

In this study therapeutic potential of fucoidan fraction-2 (Fu-F2) isolated from Sargassum polycystum was evaluated for the development of antibacterial agent against the human and animal pathogenic bacteria by in vitro and in vivo analysis. The Fu-F2 contained 51.12 ±â€¯0.86% of total sugar and 20.41 ±â€¯0.91% of sulfate. The structural characterization of Fu-F2 was performed by HPLC, FTIR and NMR analysis and reported in our earlier study. The in vitro antibacterial assays such as MIC, MBC, killing kinetics, disk diffusion, protein leakage, ROS and confocal laser scanning microscopy demonstrate that Fu-F2 possesses the highest antibacterial activity against the tested pathogens. Among the tested pathogens, the highest antibacterial activity (21 ±â€¯1.0 mm) was recorded at the concentration of 50 µg/ml against Pseudomonas aeruginosa and the lowest activity (16 ±â€¯0.53 mm) was registered against Staphylococcus aureus. In the in vivo analysis, the pre-treatment group with Fu-F2 at the concentration of 15 mg/0.1 kg through feed exhibited the highest survival (83.4%) and antioxidant activities (p < 0.05) than the fish infected with pathogen. Thus, the present findings suggest that the Fu-F2 of S. polycystum encompasses significant antibacterial properties and that can be used as a therapeutic agent for controlling the bacterial disease.

Investigation of antioxidant and anticancer potential of fucoidan from Sargassum polycystum.

The present study was aimed to evaluate the antioxidant and anticancer potential of fucoidan isolated from Sargassum polycystum. The isolated fucoidan was successfully purified by DEAE cellulose-ion exchange chromatography and dialysis. Totally four active fractions (F1-F4) were collected and explored its chemical constitution by calorimetric assays. Among them, fraction 2 (F2) showed the higher yield percentage, fucose and sulphate content. Further, monosaccharide composition, structural and functional properties of the F2 was analyzed by HPLC, FTIR and NMR. F2 shows highest DPPH radical scavenging activity (55.94 ±â€¯0.69%), reducing power (0.33 absorbance rate), hydrogen peroxide scavenging activity (71.76 ±â€¯2.14%) and nitric oxide radical scavenging activity (51.81 ±â€¯1.04%) at 1000 µg/ml. The cell viability of MCF-7 and HCT-15 cell lines was proportionate to the concentration of F2 with an estimated IC50 was 20 and 50 µg/ml respectively. The fluorescence and confocal laser scanning microscopic analysis demonstrated the apoptotic morphological changes and cell mediated death in F2 treated cancer cells. Higher amount of LDH release was found in the F2 treated cancer cells than the control group. Thus, the present finding proved that the isolated F2 encompasses significant antioxidant and anticancer property.

Exploitation of chemical, herbal and nanoformulated acaricides to control the cattle tick, Rhipicephalus (Boophilus) microplus - A review.

The tick Rhipicephalus (Boophilus) microplus is a key vector of bacterial and protozoan diseases causing heavy economic losses directly and indirectly in animal husbandry. In the past decades, the control of ticks faced some major issues, such as the rapid development of resistance in targeted vectors and non-target effects on human health and the environment, due to the employ of synthetic acaricides and repellents. Eco-friendly pesticides for treating and controlling animal parasites such as ticks were mainly from medicinal plants and thus they form the richest entity for manufacturing resources for drugs. Even though there are efforts made to discover reliable plant-based acaricides to control ectoparasites in animal husbandry, the effective control of R. (B.) microplus ticks still represent a major challenge in current veterinary entomology. Recently, a wide number of promising attempts have been conducted to use herbal preparations and green-fabricated nanoparticles for the control of R. (B.) microplus. The aim of this review is to critically summarize and discuss the use of herbal preparations used in ethno-veterinary as well as green-fabricated nanoparticles as novel acaricides for the control of the cattle tick R. (B.) microplus.

In vitro antioxidant and antibacterial activity of sulfated polysaccharides isolated from Spatoglossum asperum.

Fucoidan was extracted productively from Spatoglossum asperum and its antioxidant and antibacterial potential against Aeromonos hydrophila was investigated. The isolated fucoidan was characterized by HPLC, FTIR, 1H and 13C NMR spectrum. The isolated fucoidan contained 60.9% fucose, 21.35±0.81% sulfate and 4.2±0.56% protein, respectively. The in vitro antioxidant activity was evaluated by DPPH radical scavenging, reducing power and total antioxidant activities. The extracted fucoidan showed antioxidant properties in a dose-dependent manner. The antibacterial activity of isolated fucoidan was tested against A. hydrophila using agar bioassay, agar well diffusion and confocal assays. In this study, the minimum inhibitory concentration was obtained at 100µg/ml and the maximum zone of inhibition (33mm) was observed at 150µg/ml of fucoidan concentration in agar bioassay and agar well diffusion assay. The experimental results proved that the extracted fucoidan from S. asperum possesses admirable antioxidant and antibacterial properties.

Isolation of fucoidan from Sargassum polycystum brown algae: Structural characterization, in vitro antioxidant and anticancer activity.

In this study antioxidant and anticancer effect of fucoidan isolated from brown seaweed Sargassum polycystum was investigated. The total yield of fucoidan was 4.51±0.24%, of these, 46.8% of fucose and 22.35±0.23% of sulphate respectively. The structural characteristic of fucoidan was analyzed by Fourier transform infrared spectroscopy and nuclear magnetic resonance. The antioxidant properties were determined by DPPH scavenging, reducing power and total antioxidant assays. The maximum DPPH scavenging activity (61.2±0.33%), reducing ability (67.56±0.26%) and total antioxidant activity (65.3±0.66%) were obtained at 1000µg/ml of fucoidan. The cytotoxicity effect of fucoidan showed a higher percentage (90.4±0.25%) of inhibition against the MCF-7 cell line at 150µg/ml with an estimated IC50 at 50µg/ml. Further, cytomorphological and apoptosis changes of fucoidan treated cells were observed under inverted light microscope and confocal laser scanning microscope (CLSM). The results demonstrated that the isolated fucoidan from S. polycystum possessed potent antioxidant and anticancer properties.

In vitro and in vivo efficacy of rosmarinic acid on quorum sensing mediated biofilm formation and virulence factor production in Aeromonas hydrophila.

Rosmarinic acid (RA) was assessed for its quorum sensing inhibitory (QSI) potential against Aeromonas hydrophila strains AH 1, AH 12 and MTCC 1739. The pathogenic strains of A. hydrophila were isolated from infected zebrafish and identified through biochemical analysis and amplification of a species-specific gene (rpsL). The biofilm inhibitory concentration (BIC) of RA against A. hydrophila strains was found to be 750 µg ml-1. At this concentration, RA reduced the QS mediated hemolysin, lipase and elastase production in A. hydrophila. In FT-IR analysis, RA treated A. hydrophila cells showed a reduction in cellular components. Gene expression analysis confirmed the down-regulation of virulence genes such as ahh1, aerA, lip and ahyB. A. hydrophila infected zebrafish upon treatment with RA showed increased survival rates. Thus, the present study demonstrates the use of RA as a plausible phytotherapeutic compound to control QS mediated biofilm formation and virulence factor production in A. hydrophila.