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1.
This study aimed to develop a mucoadhesive polymeric excipient comprising curcumin for buccal delivery. Curcumin encompasses broad range of benefits such as antioxidant, anti-inflammatory, and chemotherapeutic activity. Hyaluronic acid (HA) as polymeric excipient was modified by immobilization of thiol bearing ligands. L-Cysteine (SH) ethyl ester was covalently attached via amide bond formation between cysteine and the carboxylic moiety of hyaluronic acid. Succeeded synthesis was proved by H-NMR and IR spectra. The obtained thiolated polymer hyaluronic acid ethyl ester (HA-SH) was evaluated in terms of stability, safety, mucoadhesiveness, drug release, and permeation-enhancing properties. HA-SH showed 2.75-fold higher swelling capacity over time in comparison to unmodified polymer. Furthermore, mucoadhesion increased 3.4-fold in case of HA-SH and drug release was increased 1.6-fold versus HA control, respectively. Curcumin-loaded HA-SH exhibits a 4.4-fold higher permeation compared with respective HA. Taking these outcomes in consideration, novel curcumin-loaded excipient, namely thiolated hyaluronic acid ethyl ester appears as promising tool for pharyngeal diseases.  相似文献   

2.
The objective of this study was to investigate the potential of liposomes as an ophthalmic delivery system for brinzolamide (Brz) to enhance the local glaucomatous therapeutic effect. The liposomes of Brz (Brz-LPs) were produced by the thin-film dispersion method with a particle size of 84.33?±?2.02 nm and an entrapment efficiency of 98.32?±?1.61%. Differential scanning calorimetry (DSC) and X-ray powder diffraction (XRD) analysis proved that Brz was successfully entrapped into Brz-LPs. Brz-LPs displayed a biphasic release pattern in vitro with burst release initially and sustained release afterwards. The corneal permeability was measured using modified Franz-type diffusion cells, and Brz-LPs showed 6.2-fold increase in the apparent permeability coefficient when compared with the commercial available formulation (B rz-Sus). Moreover, Brz-LPs (1 mg/mL Brz) showed a more sustained and effective intraocular pressure reduction (5–10 mmHg) than Brz-Sus (10 mg/mL Brz) in white New Zealand rabbits. Therefore, Brz-LPs were a hopeful formulation of Brz for glaucoma treatment and worthy of further investigation.  相似文献   

3.
The aim of this study was to evaluate the impact of various vehicles on mucoadhesive properties of thiolated chitosan nanoparticles both in vitro and in vivo. Nanoparticles (NPs) were prepared by in situ gelation technique followed by labeling with fluorescein diacetate. Comparative studies on mucoadhesion were done with these thiolated chitosan NPs and unmodified chitosan NPs (control). The obtained nanoparticles displayed a mean diameter of 164.2 ± 6.9 nm and a zeta potential of 21.5 ± 5 mV. In an in vitro adhesion study, unhydrated thiolated NPs adhered strongly to freshly excised porcine small intestine, which was more than threefold increase compared to the control. In contrast, in the presence of various vehicles (PEG 300, miglyol 840, PEG 6000, cremophor EL, and caprylic triglyceride), the mucoadhesive properties of thiolated NPs were comparatively weak. Thiolated NPs suspended in caprylic triglyceride, for example, had a percent mucoadhesion of 22.50 ± 5.35% on the mucosa. Furthermore, results from in vivo mucoadhesion studies revealed that the dry form of nanoparticles exhibits the strongest mucoadhesion, followed by nanoparticles suspended in PEG 300, miglyol, and 100 mM phosphate buffer, in that order. Three hours after administration, the gastrointestinal residence time of the dry form of thiolated NPs was up to 3.6-fold prolonged. These findings should contribute to the design of highly effective oral mucoadhesive nanoparticulate drug delivery systems.  相似文献   

4.
The aim of this study is to develop an orally disintegrating film (ODF) containing a microparticulate measles vaccine formulation for buccal delivery. The measles vaccine microparticles were made with biocompatible and biodegradable bovine serum albumin (BSA) and processed by spray drying. These vaccine microparticles were incorporated in the ODF, consisting of Lycoat RS720®, Neosorb P60W® and Tween 80. The yield of the microparticles was approximately 85–95%, w/w. The mean size of the vaccine microparticles was 3.65?±?1.89 μm and had a slightly negative surface charge of 32.65?±?2.4 mV. The vaccine particles were nontoxic to normal cells at high concentrations (500 μg/2.5?×?105 cells) of vaccine particles. There was a significant induction of innate immune response by vaccine microparticles which was observed in vitro when compared to blank microparticles (P?<?0.05). The vaccine microparticles also significantly increased the antigen presentation and co-stimulatory molecules expression on antigen presenting cells, which is a prerequisite for Th1 and Th2 immune responses. When the ODF vaccine formulation was dosed in juvenile pigs, significantly higher antibody titers were observed after week 2, with a significant increase at week 4 and plateauing through week 6 comparative to naïve predose titers. The results suggest that the ODF measles vaccine formulation is a viable dosage form alternative to noninvasive immunization that may increase patient compliance and commercial distribution.  相似文献   

5.
This study was conducted to develop timolol maleate (TM)-loaded galactosylated chitosan (GC) nanoparticles (NPs) (TM-GC-NPs) followed by optimization via a four-level and three-factor Box–Behnken statistical experimental design. The optimized nanoparticles showed a particle size of 213.3?±?6.83 nm with entrapment efficiency of 38.58?±?1.31% and drug loading of 17.72?±?0.28%. The NPs were characterized with respect to zeta potential, pH, surface morphology, and differential scanning calorimetry (DSC). The determination of the oil–water partition coefficient demonstrated that the TM-GC-NPs had a high liposolubility at pH 6 as compared to timolol-loaded chitosan nanoparticles (TM-CS-NPs) and commercial TM eye drops. The in vitro release study indicated that TM-GC-NPs had a sustained release effect compared with the commercial TM eye drops. Ocular tolerance was studied by the hen’s egg chorioallantoic membrane (HET-CAM) assay and the formulation was non-irritant and could be used for ophthalmic drug delivery. The in vitro transcorneal permeation study and confocal microscopy showed enhanced penetration, and retention in the cornea was achieved with TM-GC-NPs compared with the TM-CS-NPs and TM eye drops. Preocular retention study indicated that the retention of TM-GC-NPs was significantly longer than that of TM eye drops. The in vivo pharmacodynamic study suggested TM-GC-NPs had a better intraocular pressure (IOP) lowering efficacy and a prolonged working time compared to commercial TM eye drops (P?≤?0.05). The optimized TM-GC-NPs could be prepared successfully promising their use as an ocular delivery system.  相似文献   

6.
Honokiol is a natural phenolic anti-cancer compound isolated from an extract of seed cones from Magnolia grandiflora. This study investigated the transdermal delivery of honokiol using various enhancement methods and to explore the potential of honokiol to treat breast cancer directly via delivery through mammary papilla. Poration of dermatomed human skin with microneedles significantly increased the delivery of honokiol by nearly 3-fold (97.81?±?18.96 μg/cm2) compared with passive delivery (32.56?±?5.67 μg/cm2). Oleic acid was found to be the best chemical penetration enhancer, increasing the delivery almost 27-fold (868.06?±?100.91 μg/cm2). Addition of oleic acid also resulted in better retention of drug in the porcine mammary papilla (965.41?±?80.26 μg/cm2) compared with breast skin (294.16?±?8.49 μg/cm2). Anti-cancer effect of honokiol was demonstrated with the decrease in the release of cytokine IL-6 and further suppression of Ki-67 proliferative protein. In addition, the topical honokiol formulation investigated was found to be safe and non-irritant. In summary, both microneedles and chemical enhancers can improve the absorption of honokiol through skin. Directly applying honokiol on mammary papilla is a potential administration route which can increase localized delivery into breast tissue.  相似文献   

7.
This study was aimed at preparing orally administered naringenin-loaded liposome for pharmacokinetic and tissue distribution studies in animal models. The liposomal system, consisting of phospholipid, cholesterol, sodium cholate, and isopropyl myristate, was prepared using the thin-film hydration method. Physicochemical characterization of naringenin-loaded liposome such as particle size, zeta potential, and encapsulation efficiency produced 70.53?±?1.71 nm, ?37.4?±?7.3 mV, and 72.2?±?0.8%, respectively. The in vitro release profile of naringenin from the formulation in three different media (HCl solution, pH 1.2; acetate buffer solution, pH 4.5; phosphate buffer solution, pH 6.8) was significantly higher than the free drug. The in vivo studies also revealed an increase in AUC of the naringenin-loaded liposome from 16648.48 to 223754.0 ng·mL?1 h as compared with the free naringenin. Thus, approximately 13.44-fold increase in relative bioavailability was observed in mice after oral administration. The tissue distribution further showed that the formulation was very predominant in the liver. These findings therefore indicated that the liposomal formulation significantly improved the solubility and oral bioavailability of naringenin, thus leading to wider clinical applications.  相似文献   

8.
The present study aimed to develop buccoadhesive film of glimepiride with unique combination of polymers and to investigate its effect(s) on physicomechanical parameters, drug-release, and permeation of films. Drug-polymer interaction was examined by FTIR and DSC analysis. Films were prepared by solvent casting technique and characterized for film strength (320?±?8.5 g, 28.98?±?2.00 mJ), buccoadhesive strength (28.8?±?1.37 g, 3.04?±?0.32 mJ), and tensile strength (260?±?6.88 g, 18.00?±?0.44 mJ) by new instrumental techniques. Increase in polymer concentration augmented zeta potential of polymeric matrix-mucin mixture and exhibited strong buccoadhesion (electrical theory). Buccoadhesion was also influenced by particle size (adsorption theory) and swelling (wetting theory). Erosion behavior of films was observed in swelling and SEM studies. Film GM4 exhibited 98?±?2% in vitro drug release and 85?±?8% ex vivo drug permeation in 12 h with controlled diffusion mechanism. Films were compatible with oral probiotic microorganisms. Stability studies revealed no significant (P?<?0.05) variation in physicomechanical characteristics.  相似文献   

9.
A Gram-stain positive, aerobic, non-motile, endospore-forming and rod-shaped strain (THG-NT9T) was isolated from a green tea sample. Growth occurred at 20–45 °C (optimum 28–35 °C), at pH 6.0–8.0 (optimum 7.0) and at 0–2.0% NaCl (optimum 0%). Based on 16S rRNA gene sequence analysis, the near phylogenetic neighbours of strain THG-NT9T were identified as Scopulibacillus daqui DSM 28236T (98.6%), Scopulibacillus darangshiensis DSM 19377T (97.4%), Pullulanibacillus pueri CGMCC 1.12777T (96.7%) and Pullulanibacillus camelliae CGMCC 1.15371T (96.3%). The DNA G?+?C content of strain THG-NT9T was determined to be 47.5 mol %. DNA–DNA hybridization values between strain THG-NT9T and S. daqui DSM 28236T, S. darangshiensis DSM 19377T, P. pueri CGMCC 1.12777T, P. camelliae CGMCC 1.15371T and Pullulanibacillus naganoensis DSM 10191T were 41.3?±?0.1 (39.4?±?0.4% reciprocal analysis), 39.1?±?0.1 (37.3?±?0.1%), 21.4?±?0.7 (20.1?±?0.3%), 20.7?±?0.1 (20.1?±?0.4%) and 12.1?±?0.2% (8.3?±?0.2%). The polar lipids were identified as diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and three unidentified lipids. The quinone was identified as MK-7. The major fatty acids were C18:3 ω7c, iso-C15:0, iso-C16:0, iso-C17:0 and anteiso-C17:0. The cell wall type was determined to be A1γ peptidoglycan with meso-diaminopimelic acid as the diagnostic diamino acid plus alanine and glutamic acid and glucose as the cell wall sugar. On the basis of the phylogenetic analysis, chemotaxonomic data, physiological characteristics, and DNA–DNA hybridization data, strain THG-NT9T represents a novel species of the genus Scopulibacillus, for which the name Scopulibacillus cellulosilyticus sp. nov. is proposed. The type strain is THG-NT9T (=?KCTC 33918T?=?CGMCC 1.16305T).  相似文献   

10.
In this study on the valorization of hemicelluloses (a co-product generated during cellulosic bioethanol production), prehydrolyzates obtained from poplar woodchips pretreated in an industrial experimental steam-explosion pilot-plant facility were evaluated for the production of bioxylitol using the yeast, Candida guilliermondii FTI 20037, employing both batch and fed-batch fermentation modes in shake flasks on defined nutrient medium. The prehydrolyzates consisted of monosaccharides (pentose and hexose sugars) as well as xylo-oligosaccharides and undegraded hemicellulose. Xylose (31.6?±?0.57 g/L) was the major sugar in the prehydrolyzates that also contained acetic acid and degradation products of lignin and sugars (phenolic and furanic compounds). Xylose in the prehydrolyzates could be further increased (106.4?±?0.02 g/L) through an acid hydrolysis step (0.6 % (w/v) H2SO4). Compounds of a toxic nature in both the acid hydrolyzates and prehydrolyzates were removed by treatment with Amberlite IRA-400 resin (chloride form). Batch fermentation of pure xylose and poplar prehydrolyzate resulted in bioxylitol production of 9.9?±?0.01 and 4.9?±?0.17 g/L, respectively, indicating that the poplar prehydrolyzates exhibited an inhibitory effect on fermentation. After detoxification of the poplar prehydrolyzates, bioxylitol production increased to 8.9?±?0.01 g/L. Fed-batch fermentation of the prehydrolyzate increased the bioxylitol production to 12.39?±?0.33 g/L, while acid hydrolysis followed by detoxification resulted in a maximum bioxylitol production of 22.0?±?0.01 g/L, a 348 % increase. The results demonstrated that acid hydrolysis and detoxification followed by fed-batch fermentation was an efficient way to produce bioxylitol from poplar prehydrolyzates.  相似文献   

11.
The expression of nine functional candidates for QT abdominal fat weight and relative abdominal fat content was investigated by real-time polymerase chain reaction (PCR) in the liver, adipose tissue, colon, muscle, pituitary gland and brain of broilers. The high mobility group AT-hook 1 (HMG1A) gene was up-regulated in liver with a ratio of means of 2.90 (P?≤?0.01) in the «fatty» group (relative abdominal fat content 3.5?±?0.18%, abdominal fat weight 35.4?±?6.09 g) relative to the «lean» group (relative abdominal fat content 1.9?±?0.56%, abdominal fat weight 19.2?±?5.06 g). Expression of this gene was highly correlated with the relative abdominal fat content (0.70, P?≤?0.01) and abdominal fat weight (0.70, P?≤?0.01). The peroxisome proliferator-activated receptor gamma (PPARG) gene was also up-regulated in the liver with a ratio of means of 3.34 (P?≤?0.01) in the «fatty» group relative to the «lean» group. Correlation of its expression was significant with both the relative abdominal fat content (0.55, P?≤?0.05) and the abdominal fat weight (0.57, P?≤?0.01). These data suggest that the HMG1A and PPARG genes were candidate genes for abdominal fat deposition in chickens. Searching of rSNPs in regulatory regions of the HMG1A and PPARG genes could provide a tool for gene-assisted selection.  相似文献   

12.
Celecoxib (Cx) shows high efficacy in the treatment of osteoarthritis and rheumatoid arthritis as a result of its high specificity for COX-2, without gastrolesivity or interference with platelet function at therapeutic concentrations. Besides of anti-inflammatory effects, Cx also has a potential role for oral cancer chemoprevention. For these conditions, oral administration in long-term treatment is a concern due to its systemic side effects. However, local application at the site of injury (e.g., buccal inflammation conditions or chemoprevention of oral cancer) is a promising way to reduce its toxicity. In this study, the in vitro characterization of mucoadhesive chitosan (CHT) gels associated to Azone® was assessed to explore the potential buccal mucosal administration of Cx in this tissue. Rheological properties of gels were analyzed by a rheometer with cone-plate geometry. In vitro Cx release and permeability studies used artificial membranes and pig cheek mucosa, respectively. Mucoadhesion were measured with a universal test machine. CHT gels (3.0%) containing 2.0% or 3.0% Az showed more appropriate characteristics compared to the others: pH values, rheology, higher amount of Cx retained in the mucosa, and minimal permeation through mucosa, besides the highest mucoadhesion values, ideal for buccal application. Moreover, the flux (J) and amounts of drug released decreased with increased CHT and Az concentrations. CHT gels (3.0%) associated with 2.0% or 3.0% Az may be considered potential delivery systems for buccal administration of Cx.  相似文献   

13.
This study was conducted to develop formulations of hydrocortisone butyrate (HB)-loaded poly(d,l-lactic-co-glycolic acid) nanoparticles (PLGA NP) suspended in thermosensitive gel to improve ocular bioavailability of HB for the treatment of bacterial corneal keratitis. PLGA NP with different surfactants such as polyvinyl alcohol (PVA), pluronic F-108, and chitosan were prepared using oil-in-water (O/W) emulsion evaporation technique. NP were characterized with respect to particle size, entrapment efficiency, polydispersity, drug loading, surface morphology, zeta potential, and crystallinity. In vitro release of HB from NP showed a biphasic release pattern with an initial burst phase followed by a sustained phase. Such burst effect was completely eliminated when nanoparticles were suspended in thermosensitive gels and zero-order release kinetics was observed. In HCEC cell line, chitosan-emulsified NP showed the highest cellular uptake efficiency over PVA- and pluronic-emulsified NP (59.09?±?6.21%, 55.74?±?6.26%, and 62.54?±?3.30%, respectively) after 4 h. However, chitosan-emulsified NP indicated significant cytotoxicity of 200 and 500 μg/mL after 48 h, while PVA- and pluronic-emulsified NP exhibited no significant cytotoxicity. PLGA NP dispersed in thermosensitive gels can be considered as a promising drug delivery system for the treatment of anterior eye diseases.  相似文献   

14.
The objective of this study comprises of developing novel co-spray dried rifampicin phospholipid lipospheres (SDRPL) to investigate its influence on rifampicin solubility and oral bioavailability. Solid-state techniques were employed to characterize the liposphere formulation. SDRPL solubility was determined in distilled water. BACTEC 460TB System was employed to evaluate SDRPL antimycobacterial activity. The oral bioavailability of the lipospheres was evaluated in Sprague Dawley rats. Lipospheres exhibited amorphous, smooth spherical morphology with a significant increase (p?<?0.001) in solubility of SDRPL (2:1), 350.9?±?23 versus 105.1?±?12 μg/ml and SDRPL (1:1) 306.4?±?20 versus 105.1?±?12 μg/ml in comparison to rifampicin (RMP). SDRPL exhibited enhanced activity against Mycobacterium tuberculosis, H37Rv strain, with over twofolds less minimum inhibitory concentration (MIC) than the free drug. Lipospheres exhibited higher peak plasma concentration (109.92?±?25 versus 54.31?±?18 μg/ml), faster T max (two versus four hours), and enhanced area under the curve (AUC0–∞) (406.92?±?18 versus 147.72?±?15 μg h/L) in comparison to pure RMP. Thus, SDRPL represents a promising carrier system exhibiting enhanced antimycobacterial activity and oral bioavailability of rifampicin.  相似文献   

15.
Silver nanoparticles (AgNPs) have several technological applications and may be synthetized by chemical, physical and biological methods. Biosynthesis using fungi has a wide enzymatic range and it is easy to handle. However, there are few reports of yeasts with biosynthetic ability to produce stable AgNPs. The purpose of this study was to isolate and identify soil yeasts (Rhodotorula glutinis and Rhodotorula mucilaginosa). After this step, the yeasts were used to obtain AgNPs with catalytic and antifungal activity evaluation. Silver Nanoparticles were characterized by UV–Vis, DLS, FTIR, XRD, EDX, SEM, TEM and AFM. The AgNPs produced by R. glutinis and R. mucilaginosa have 15.45?±?7.94 nm and 13.70?±?8.21 nm (average?±?SD), respectively, when analyzed by TEM. AgNPs showed high catalytic capacity in the degradation of 4-nitrophenol and methylene blue. In addition, AgNPs showed high antifungal activity against Candida parapsilosis and increase the activity of fluconazole (42.2% for R. glutinis and 29.7% for R. mucilaginosa), while the cytotoxicity of AgNPs was only observed at high concentrations. Finally, two yeasts with the ability to produce AgNPs were described and these particles showed multifunctionality and can represent a technological alternative in many different areas with potential applications.  相似文献   

16.
The current study aimed to develop a prolonged-release pramipexole (PPX) transdermal patch for the treatment of Parkinson’s disease. Permeation parameters of PPX were investigated using human cadaver skin. Pramipexole patches were prepared using DURO-TAK® pressure-sensitive-adhesive (PSA) and evaluated for drug stability, drug loading, in vitro drug release, and in vitro permeation through mouse skin. The results indicated that blends of DURO-TAK® 87-2852 and DURO-TAK® 87-2510 were suitable for creating a prolonged-release PPX patch due to their advantages in drug release, drug loading, and stability. The final formulation consisted of 87-2852/87-2510 (70:30), 10% PG, and 15% PPX and showed a cumulative permeation amount of 1497.19?±?102.90 μg/cm2 with a continuous flux over 6.0 μg/(cm2·h) across human cadaver skin for 7 days. In vivo studies in rats indicated that PPX patch produced a significantly longer (p?<?0.001) half-life (t 1/2, 75.16?±?17.37 h) and mean residence time (MRT, 135.89?±?24.12 h) relative to oral tablets (Sifrol®) and had a relative bioavailability of 51.64?±?21.32%. Therefore, this study demonstrated the feasibility of developing a prolonged-release PPX patch, which proposed the potential to serve as an alternate to conventional oral tablets and may therefore improve patient compliance.  相似文献   

17.
Microalgal production has many advantages over the use of terrestrial plants; therefore, increases in the use of microalgae for energy production can be expected. Algal biomass can be processed anaerobically to methane; however, the unfavorable C/N ratio of the substrate may have an inhibitory effect. The impact of the application of used cooking oil, maize silage, and mill residue on anaerobic co-digestion of the microalgal Chlorella vulgaris was studied in semi-continuous, laboratory-scale digestion. During the full period of the trial involving anaerobic digestion of algae in the case of mono-digestion and co-digestion with used cooking oil, maize silage, and mill residue, the volumetric methane yields were 0.38?±?0.07, 1.56?±?0.26, 1.19?±?0.18, and 1.16?±?0.13 L L?1, respectively. Trials were carried out to determine the long-term effect of the total solid (TS) content of substrates (co-digestion of C. vulgaris and used cooking oil at 3.8 and 7.2 % of TS, respectively). Both designs could be increased to 5.5 g VS L?1 d?1, but a higher TS% resulted in increased methane production and a longer period of decline in the methane yield due to washout. The sharp decrease in methane content at the end of 90 days was accompanied by a reorganization of the methanogenic archaeal community.  相似文献   

18.
Inheritance pattern of wood traits viz. specific gravity, fibre dimensions and fibre-derived biometrical indices and their interactions among themselves and with that of growth are reported in Hevea brasiliensis. Girth (h2 =???0.02?±?0.44 to h2 =?0.35?±?0.24) showed moderate genetic control. Among wood traits, specific gravity (h2?=?0.15?±?0.31 to h2 =?0.33?±?0.28) was found to be under moderate genetic control. Fibre traits viz., fibre length (h2 =???0.26?±?0.30 to h2 =?0.50?±?0.34), fibre diameter (h2 =?0.19?±?0.49 to h2 =?0.70?±?0.11), fibre lumen diameter (h2 =???0.18?±?0.35 to h2 =?0.56?±?0.47) and fibre wall thickness (h2 =???5.17?±?5.26 to h2 =?0.50?±?0.50) were under moderate to strong genetic control. Among fibre-derived indices, flexibility coefficient (h2 =?0.48?±?0.21 to h2 =?0.89?±?0.29) showed moderate to very strong genetic control. The Runkel ratio (h2 =???0.40?±?0.27 to h2 =?0.42?±?0.29) and slenderness ratio (h2 =???0.36?±?0.29 to h2 =?0.43?±?0.28) showed moderate genetic control. Girth showed very strong positive genetic correlation with fibre wall thickness and strong positive correlation with fibre width indicating scope of indirect selection potential for these traits. Wood specific gravity was not correlated with either girth or fibre traits. Hence, it would be possible to concomitantly improve growth and fibre traits without adversely affecting wood specific gravity. Moderate to very high estimates of heritability for fibre traits, girth and specific gravity indicated that considerable genetic gain can be realised for these traits. Implications of the above findings in genetic improvement of wood in Hevea are discussed.  相似文献   

19.
In the present study, ethanolic extracts of ten cyanobacterial strains cultivated under different nitrogen conditions were assessed for the phenolic content and antioxidant activity. The amount of detected phenolic compounds ranged from 14.86 to 701.69 μg g?1 dry weight (dw) and HPLC-MS/MS analysis revealed gallic acid, chlorogenic acid, quinic acid, catechin, epicatechin, kaempferol, rutin and apiin. Only catechin, among the detected phenolics, was present in all the tested strains, while quinic acid was the most dominant compound in all the tested Nostoc strains. The results also indicated the possibility of increasing the phenolic content in cyanobacterial biomass by manipulating nitrogen conditions, such as in the case of quinic acid in Nostoc 2S7B from 70.83 to 594.43 μg g?1 dw. The highest radical scavenging activity in DPPH assay expressed Nostoc LC1B with IC50 value of 0.04?±?0.01 mg mL?1, while Nostoc 2S3B with IC50 =?9.47?±?3.61 mg mL?1 was the least potent. Furthermore, the reducing power determined by FRAP assay ranged from 8.36?±?0.08 to 21.01?±?1.66 mg AAE g?1, and it was significantly different among the tested genera. The Arthrospira strains exhibited the highest activity, which in the case of Arthrospira S1 was approximately twofold higher in comparison to those in nitrogen-fixing strains. In addition to this, statistical analysis has indicated that detected phenolics were not major contributor to antioxidant capacities of tested cyanobacteria. However, this study highlights cyanobacteria of the genera Nostoc, Anabaena, and Arthrospira as producers of antioxidants and phenolics with pharmacological and health-beneficial effects, i.e., quinic acid and catechin in particular.  相似文献   

20.
The objective of this study was to evaluate the efficacy of three eco-friendly control agents, either singly or in a pairwise combination, for the control of the tomato leafminer, Tuta absoluta (Meyrick) (Lep: Gelechiidae). They include the naturally derived pesticide spinosad, a commercially available formulation of Bacillus thuringiensis var. Kurstaki (Bt), and a native population of Trichogramma brassicae Bezdenko (Hym: Trichogrammatidae). Tomato plants containing the T. absoluta were treated with one of the seven following treatments in a greenhouse: (1) a single release of T. brassicae against the eggs; (2) two applications of Bt (2 kg ha?1); (3) and (4) one application of spinosad at two rates (60 and 120 g a.i. ha?1); (5) T. brassicae release?+?Bt spray; (6) T. brassicae release?+?spinosad spray; and (7) spinosad spray?+?Bt spray. The highest mortality rate was recorded for the spinosad?+?Bt (88.33?±?1.43%) and T. brassicae?+?spinosad (78.33?±?3.74%) combinations, respectively; while the lowest mortality rate was obtained through the single application of T. brassicae (31.67?±?4.84%). Based on our results, the Bt and spinosad seem to be suitable candidates for combination with other biological and cultural techniques towards an integrated management of the tomato leafminer.  相似文献   

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