Tunable Cytotoxicity and Selectivity of Phosphonium Ionic Liquid with Aniline Blue Dye

Ionic liquids are an interesting class of materials that have recently been utilized as chemotherapeutic agents in cancer therapy. Aniline blue, a commonly used biological staining agent, was used as a counter ion to trihexyltetradecylphosphonium, a known cytotoxic cation. A facile, single step ion exchange reaction was performed to synthesize a fluorescent ionic liquid, trihexyltetradecylphosphonium aniline blue. Aqueous nanoparticles of this hydrophobic ionic liquid were prepared using reprecipitationmethod. The newly synthesized ionic liquid and subsequent nanoparticles were characterized using various spectroscopic techniques. Transmission electron microscopy and zeta potential measurements were performed to characterize the nanoparticles’ morphology and surface charge. The photophysical properties of the nanoparticles and the parent aniline blue compound were studied using absorption and fluorescence spectroscopy. Cell viability studies were conducted to investigate the cytotoxicity of the newly developed trihexyltetradecylphosphonium aniline blue nanoparticles in human breast epithelial cancer cell line (MCF-7) and its corresponding normal epithelial cell line (MCF-10A) in vitro. The results revealed that the synthesized ionic nanomedicines were more cytotoxic (lower IC50) than the parent chemotherapeutic compound in MCF-7 cells. Nanoparticles of the synthesized ionic liquid were also shown to be more stable in both aqueous and cellular media and more selective than parent compounds towards cancer cells.

Novosphingobium decolorationis sp. nov., an aniline blue-decolourizing bacterium isolated from East Pacific sediment

Aniline blue-decolourizing bacterial strain 502str22T, isolated from sediment collected in the East Pacific, was subjected to characterization by a polyphasic taxonomic approach. Phylogenetic analyses based on 16S rRNA gene sequences revealed that strain 502str22T belongs to the genus Novosphingobium , with closely related type strains ‘ Novosphingobium profundi ’ F72T (97.6%), N. mathurense SM117T (97.1%) and N. arvoryzae Jyi-02T (97.0%). Digital DNA–DNA hybridization and average nucleotide identity values between strain 502str22T and closely related type strains were 20.3–24.8% and 74.1–81.9%, respectively. The major cellular fatty acid (>10%) was C18:1 ω7c. The polar lipid profile consisted of a mixture of phosphatidylcholine, one sphingoglycolipid, diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and phosphatidylmonomethylethanolamine. The DNA G+C content of strain 502str22T was 65.5 mol%. The polyphasic taxonomic results indicated that strain 502str22T represents a novel species of the genus Novosphingobium , for which the name Novosphingobium decolorationis sp. nov is proposed. The type strain is 502str22T (=KCTC 82134T= MCCC 1K04799 T).

A review presenting production, characterization, and applications of biopolymer curdlan in food and pharmaceutical sectors

Curdlan is an exopolysaccharide, specifically a homopolysaccharide, with a high molecular weight that is made up entirely of monomeric glucose molecules connected by β-1,3-glycosidic bonds. Curdlan was first isolated in 1962 by Harada and his colleagues from Alcaligenes faecalis var myxogenes 10C3. Microbial synthesis of this curdlan is mainly associated with soil bacteria. Preliminary screening of curdlan-producing microorganisms is done on aniline blue media. The aniline blue positive microorganisms are subjected to submerged fermentation for the production of curdlan. To improve the yield of curdlan produced, various optimization techniques are employed such as Plackett–Burman, response surface methodology, and others. Curdlan can be characterized by its morphology, gel strength, its infrared, and magnetic resonances among many other characteristics. Due to its distinctive physicochemical and rheological properties, it has gained immense popularity in the food, biomedical, and pharmaceutical sectors. However, curdlan’s functionality can be improved by chemically modifying curdlan to obtain grafted curdlan, hydrogels, and nanocomposites which are discussed in detail herewith. Curdlan was authorized to be used in the food industry by the United States Food and Drug Administration in 1996 and also in 1989 in Taiwan, Japan, and Korea. Over the years, many patents using curdlan have also been filed from different parts of the world. This review provides information about its structure, biosynthesis, production strategies, optimization, characterization, applications, and patents. Graphic abstract

P–074 Chromatin Maturity Index (CMI) in unfixed and live spermatozoa and Aniline Blue (AB) stained as an additional evaluation parameter in idiopathic male infertility

Study question To investigate whether idiopathic male infertility may be due to the presence of histones in motile spermatozoa using a modified AB staining protocol. Summary answer No correlation between CMI in live motile spermatozoa, DNA Fragmentation Index (DFI) and other conventional seminal parameters were found in male infertile patients. What is known already The AB stain discriminates between lysine-rich histones and arginine/cysteine-rich protamines. Transition from histones to protamines during spermatogenesis remodels chromatin packaging and abnormalities in the substitution of those proteins maybe interfere with seminal parameters and affect male infertility. The correlation between CMI and seminal parameters is known, but little is knowledge about live and motile spermatozoa associated to CMI because literature report only spermatozoa fixation before staining. Sperm chromatin carries half of the genomic material to offspring. Spermatozoa nuclear status is crucial for balanced transmission to future generations, and histones modifications are directly involved in epigenetic mutations. Study design, size, duration Retrospective observational study of 77 men underwent to standard semen analysis, including the evaluation of CMI and DFI, enrolled from January to December 2020. Mean age of the men was 36.63±8.26 years old, sperm concentration 46.69±37.23 mill/mL, linear progressive motility 39.35±15.31%, normal morphology 6.42±3.40%, DFI 25.91±10.29%. 200 spermatozoa for evaluation of CMI and 300 for DFI were analyzed respectively. Participants/materials, setting, methods Semen samples of 77 patients were collected and analyzed according to 5th edition of WHO guidelines (2010) for examination of human semen. For the evaluation of CMI we performed a new modified protocol for AB stain directly in live spermatozoa. Dilution 1:1 fresh semen and Aniline Blue colorant were mixed and placed on a slide and examined in bright field microscopy x1000 magnification. DFI was evaluated using Sperm Chromatin Dispersion (SCD) test. Main results and the role of chance Of all spermatozoa analyzed, 82.58±29.98% were white, 17.17±17.21% were pale blue, and 28.53±21.09% were dark blue. By our modified protocol, directly in live spermatozoa, we correlated AB staining with motility and , surprisingly, all motile spermatozoa observed were not stained (white), while pale or dark blue spermatozoa resulted always immotile. For this reason, we have considered pale blue spermatozoa as AB positive, in disagreement with some authors. So, maybe, we should reconsider pale blue stained spermatozoa as abnormal. We also observed AB negative spermatozoa with morphological head, neck and tail defects, underlining the independence of these two parameters: nuclear status and morphology. We have observed no statistically significant differences between conventional semen parameters, DFI and CMI, so nuclear analysis seems to be independent parameters. The statistical analysis was performed by Matlab statistical toolbox version 2008 (MathWorks, Natick, MA, USA) for Windows at 32 bit; finally all tests with p-value (p) < 0.05 were considered significant. Attention should be paid to the evaluation of CMI not only in astenozoospermic patients, where a lower CMI is known, but also in normozoospermic infertile patients. Limitations, reasons for caution This is a preliminary observational study on a small number of normozoospermic or mild asthenozoospermic patients. The study should be considered as a pilot study. Future studies with higher number of samples are necessary in order to confirm the results obtained. Wider implications of the findings: This is the first study that reports AB staining on unfixed live spermatozoa with a modified protocol. Our study underlines the necessity of classify pale blue spermatozoa as AB positive. Further investigations are necessary. This is a starting point for future analysis to be carried out under the project EcoFoodFertility. Trial registration number Not applicable