Streptomycin Sulfate–Loaded Niosomes Enables Increased Antimicrobial and Anti-Biofilm Activities

One of the antibiotics used to treat infections is streptomycin sulfate that inhibits both Gram-negative and -positive bacteria. Nanoparticles are suitable carriers for the direct delivery and release of drug agents to infected locations. Niosomes are one of the new drug delivery systems that have received much attention today due to their excellent biofilm penetration property and controlled release. In this study, niosomes containing streptomycin sulfate were prepared by using the thin layer hydration method and optimized based on the size, polydispersity index (PDI), and encapsulation efficiency (EE%) characteristics. It was found that the Span 60-to-Tween 60 ratio of 1.5 and the surfactant-to-cholesterol ratio of 1.02 led to an optimum formulation with a minimum of size, low PDI, and maximum of EE of 97.8 nm, 0.27, and 86.7%, respectively. The drug release investigation showed that 50.0 ± 1.2% of streptomycin sulfate was released from the niosome in 24 h and reached 66.4 ± 1.3% by the end of 72 h. Two-month stability studies at 25° and 4°C showed more acceptable stability of samples kept at 4°C. Consequently, antimicrobial and anti-biofilm activities of streptomycin sulfate–loaded niosomes against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa were found significantly higher than those of free drug, and the minimum inhibitory concentration values decreased 4- to 8-fold. Furthermore, niosome-encapsulated streptomycin up to 1,500 μg/ml exhibited negligible cytotoxicity against the human foreskin fibroblasts cell line, whereas the free drug exhibited slight cytotoxicity at this concentration. Desired physical characteristics and low toxicity of niosomal nano-carriers containing streptomycin sulfate made them a demanded candidate for the treatment of current bacterial infections and biofilms.

Study on infection of blueberry explants with different antibiotics

The effects of streptomycin sulfate, carbendazim, penicillin and nystatin on the inhibition of fungi and bacteria in blueberry explants were studied. The results showed that the addition of streptomycin sulfate or penicillin with different concentrations in the medium had a certain inhibitory and killing effect on bacteria in blueberry explant contamination, while the addition of carbendazim or nystatin had a certain inhibitory and killing effect on fungi in blueberry explant contamination. When the concentration of streptomycin sulfate in the medium reached 60units / mL, the highest survival rate was 44.0%, and the bacterial infection rate was the lowest. When the concentration of carbendazim in the medium was 0.4 mg/mL, the survival rate reached 40.5%, and the fungal infection rate decreased greatly. When the penicillin concentration in the medium reached 40mg/mL, the lowest infection rate of bacteria was 4.0%, and the highest survival rate was 31.5%. When the concentration of nystatin in the medium reached 40mg/L, the highest survival rate was 34.5%. Therefore, streptomycin sulfate had better inhibitory effect on bacteria, while carbendazim had better inhibitory effect on fungi, which provided reference for future research.

Validation of TLC-contact bioautography and TLC-densitometry methods for simultaneous limit test of streptomycin sulfate and kanamycin sulfate residues in fresh fish meat

A simple, sensitive, and accurate TLC method was combined and validated for a simultaneous limit test of streptomycin sulfate and kanamycin sulfate residues in fresh fish meat. The optimum mobile phase was 10% potassium dihydrogen phosphate. TLC-contact bioautography used Staphylococcus aureus ATCC 29737 as a test organism. For TLC-densitometry, analyte spots were detected using 1% w/v ninhydrin in ethanol and maximum absorbance at 400 nm. TLC-contact bioautography and TLC-densitometry methods were validated according to USP guidelines for the limit test with respect to selectivity and limit of detection (LOD) added with the accuracy of a recovery test of streptomycin sulfate and kanamycin sulfate in fresh fish samples was developed and validated. The result of LOD from the TLC-contact bioautography method for streptomycin sulfate and kanamycin sulfate were obtained 0.7028 μg and 0.8032 μg, respectively. Meanwhile, LOD of the TLC-densitometry method for streptomycin sulfate and kanamycin sulfate were obtained 0.0631 μg and 0.0685 μg, respectively. In this study, TLC-contact bioautography method showed better results than TLC-densitometry. TLC-contact bioautography appears a good choice for the simultaneous limit test of streptomycin sulfate and kanamycin sulfate residues in fresh fish samples.

The Development of a Turbidimetric Method for the Quantitative Determination of Antibiotics of the Aminoglycoside Group in Medications

A method for the quantitative determination of streptomycin sulfate in medicines by the turbidimetric method has been developedand validated. Based on the results of the experiments, it was found that the metrological characteristics of such validation parameters of the method as linearity, precision, and correctness do not exceed the validation criteria. Linearity was noted in the range of streptomycin concentrations from 3.75 to 8.43 μg/ml. The results of validation tests of the method for the quantitative determination of streptomycin indicate the prospects and feasibility of introducing the turbidimetric method into the domestic system for standardization and quality assessment of aminoglycoside antibiotics.