Structural and biofunctional evaluation of decellularized jellyfish matrices.

Extracellular matrices decellularized from marine animal tissues are emerging scaffolds in tissue engineering. Jellyfish tissues are suitable for making functional and safe decellularized matrices in part due to their simple structure, high water content, and low risk of pathogen transmission to humans. Jellyfish are some of the most prevalent marine animals, but their decellularized matrices have remained largely undeveloped. Here we evaluated the structures and functions of the jellyfish (Rhopilema esculentum) matrices decellularized with seven different detergents. All of them showed effectiveness in removing the cellular components. Scanning electron microscopy and mechanical testing revealed that the decellularized matrices mostly retained the native microstructures, whereas only SDS and SNL distorted the matrices' multilayered and fibrous architecture. The collagen hybridizing peptide fluorescence staining showed that SDS, SNL, Triton X-100, IGEPAL, and Tween-20 denatured the jellyfish collagen molecules to varying degrees while CHAPS and SD protected the collagen's triple-helix conformation. We demonstrated that the decellularized jellyfish matrices showed similarity to different types of mammalian collagen and supported the adhesion and proliferation of human dermal and corneal fibroblasts and mouse chondrocytes in 3D culture. Importantly, the decellularized jellyfish matrix also facilitated wound healing in vivo by reducing inflammation while promoting angiogenesis and tissue remodeling. Taken together, our study demonstrated that the decellularized jellyfish matrices are an easy-to-prepare, biocompatible, and potentially widely applicable scaffold for regenerative medicine.

Metabolic Profiling by GC-MS, In Vitro Biological Potential, and In Silico Molecular Docking Studies of Verbena officinalis.

Verbena officinalis L. is a traditionally important medicinal herb that has a rich source of bioactive phytoconstituents with biological benefits. The objective of this study was to assess the metabolic profile and in vitro biological potential of V. officinalis. The bioactive phytoconstituents were evaluated by preliminary phytochemical studies, estimation of polyphenolic contents, and gas chromatography-mass spectrometry (GC-MS) analysis of all fractions (crude methanolic, n-hexane, ethyl acetate, and n-butanol) of V. officinalis. The biological investigation was performed by different assays including antioxidant assays (DPPH, ABTS, CUPRAC, and FRAP), enzyme inhibition assays (urease and α-glucosidase), and hemolytic activity. The ethyl acetate extract had the maximum concentration of total phenolic and total flavonoid contents (394.30 ± 1.09 mg GAE·g-1 DE and 137.35 ± 0.94 mg QE·g-1 DE, respectively). Significant antioxidant potential was observed in all fractions by all four antioxidant methods. Maximum urease inhibitory activity in terms of IC50 value was shown by ethyl acetate fraction (10 ± 1.60 µg mL-1) in comparison to standard hydroxy urea (9.8 ± 1.20 µg·mL-1). The n-hexane extract showed good α-glucosidase inhibitory efficacy (420 ± 20 µg·mL-1) as compared to other extract/fractions. Minimum hemolytic activity was found in crude methanolic fraction (6.5 ± 0.94%) in comparison to positive standard Triton X-100 (93.5 ± 0.48%). The GC-MS analysis of all extract/fractions of V. officinalis including crude methanolic, n-hexane, ethyl acetate, and n-butanol fractions, resulted in the identification of 24, 56, 25, and 9 bioactive compounds, respectively, with 80% quality index. Furthermore, the bioactive compounds identified by GC-MS were analyzed using in silico molecular docking studies to determine the binding affinity between ligands and enzymes (urease and α-glucosidase). In conclusion, V. officinalis possesses multiple therapeutical potentials, and further research is needed to explore its use in the treatment of chronic diseases.

Establishment of decellularized extracellular matrix scaffold derived from caprine pancreas as a novel alternative template over porcine pancreatic scaffold for prospective biomedical application.

In this study, the caprine pancreas has been presented as an alternative to the porcine organ for pancreatic xenotransplantation with lesser risk factors. The obtained caprine pancreas underwent a systematic cycle of detergent perfusion for decellularization. It was perfused using anionic (0.5% w/v sodium dodecyl sulfate) as well as non-ionic (0.1% v/v triton X-100, t-octyl phenoxy polyethoxy ethanol) detergents and washed intermittently with 1XPBS supplemented with 0.1% v/v antibiotic and nucleases in a gravitation-driven set-up. After 48 h, a white decellularized pancreas was obtained, and its extracellular matrix (ECM) content was examined for scaffold-like properties. The ECM content was assessed for removal of cellular content, and nuclear material was evaluated with temporal H&E staining. Quantified DNA was found to be present in a negligible amount in the resultant decellularized pancreas tissue (DPT), thus prohibiting it from triggering any immunogenicity. Collagen and fibronectin were confirmed to be preserved upon trichrome and immunohistochemical staining, respectively. SEM and AFM images reveal interconnected collagen fibril networks in the DPT, confirming that collagen was unaffected. sGAG was visualized using Prussian blue staining and quantified with DMMB assay, where DPT has effectively retained this ECM component. Uniaxial tensile analysis revealed that DPT possesses better elasticity than NPT (native pancreatic tissue). Physical parameters like tensile strength, stiffness, biodegradation, and swelling index were retained in the DPT with negligible loss. The cytocompatibility analysis of DPT has shown no cytotoxic effect for up to 72 h on normal insulin-producing cells (MIN-6) and cancerous glioblastoma (LN229) cells in vitro. The scaffold was recellularized using isolated mouse islets, which have established in vitro cell proliferation for up to 9 days. The scaffold received at the end of the decellularization cycle was found to be non-toxic to the cells, retained biological and physical properties of the native ECM, suitable for recellularization, and can be used as a safer and better alternative as a transplantable organ from a xenogeneic source.

Decellularization with triton X-100 provides a suitable model for human kidney bioengineering using human mesenchymal stem cells.

AIMS: Regeneration of discarded human kidneys has been considered as an ideal approach to overcome organ shortage for the end-stage renal diseases (ESRDs). The aim of this study was to develop an effective method for preparation of kidney scaffolds that retain the matrix structure required for proliferation and importantly, differentiation of human adipose-derived mesenchymal stem cells (hAd-MSCs) into renal cells. MAIN METHODS: We first compared two different methods using triton X-100 and sodium dodecyl sulfate (SDS) for human kidney decellularization; followed by characterization of the prepared human renal extracellular matrix (ECM) scaffolds. Then, hAd-MSCs were seeded on the scaffolds and cultured for up to 3 weeks. Next, viability, proliferation, and migration of seeded hAd-MSCs underwent histological and scanning electron microscopy (SEM) assessments. Moreover, differentiation of hAd-MSCs into kidney-specific cell types was examined using immunohistochemistry (IHC) staining and qRT-PCR. KEY FINDINGS: Our results indicated that triton X-100 was a more effective detergent for decellularization of human kidneys compared with SDS. Moreover, attachment and proliferation of hAd-MSCs within the recellularized human kidney scaffolds, were confirmed. Seeded cells expressed epithelial and endothelial differentiation markers, and qRT-PCR results indicated increased expression of platelet and endothelial cell adhesion molecule 1 (PECAM-1), paired box 2 (PAX2), and E-cadherine (E-CDH) as markers of differentiation into epithelial and endothelial cells. SIGNIFICANCE: These observations indicate the effectiveness of decellularization with triton X-100 to generate suitable human ECM renal scaffolds, which supported adhesion and proliferation of hAd-MSCs and could induce their differentiation towards a renal lineage.

Preparation of decellularized optic nerve grafts.

BACKGROUND: Decellularized tissues based on well-conserved extracellular matrices (ECMs) are a common area of research in tissue engineering. Although several decellularization protocols have been suggested for several types of tissues, studies on the optic nerve have been limited. METHODS: We report decellularization protocol with different detergent for the preparation of acellular optic nerve and tissues were examined. DNA, glycosaminoglycan (GAG), and collagen content of the groups were evaluated with biochemical analyses and examined with histological staining. Mechanical properties, chemical components as well as cytotoxic properties of tissues were compared. RESULTS: According to the results, it was determined that TX-100 (Triton X-100) was insufficient in decellularization when used alone. In addition, it was noticed that 85% of GAG content was preserved by using TX-100 and TX-100-SD (sodium deoxycholate), while this ratio was calculated as 30% for SDS. In contrast, the effect of the decellularization protocols on ECM structure of the tissues was evaluated by scanning and transmission electron microscopy (SEM and TEM) and determined their mechanical properties. Cytotoxicity analyses were exhibited minimum 95% cell viability for all groups, suggesting that there are no cytotoxic properties of the methods on L929 mouse fibroblast cells. CONCLUSIONS: The combination of TX-100-SD and TX-100-SDS (sodium dodecyl sulfate) were was determined as the most effective methods to the literature for optic nerve decellularization.

A reversed phase HPLC-UV method for the simultaneous determination of residual formaldehyde and Triton X-100 in vaccine products.

Many of the inactivated viral vaccines for human and animal use are manufactured using formaldehyde as an inactivating agent. Apart from formaldehyde, Triton X-100 is also one of the chemicals commonly used in viral vaccine manufacturing. Triton X-100 is typically used to extract the cell-associated viruses and / or components during manufacturing process. The concentration of formaldehyde and Triton X-100 in the final bulks are also reduced during vaccine purification process. Here we report a simple RP-HPLC-UV based method for the quantification of residual Triton X-100 and formaldehyde as process impurities in viral vaccines. This method is also adopted for the residual impurity determination of either formaldehyde or Triton X-100 in other non-viral vaccines, multivalent as well as sub-unit vaccines, such as liquid pentavalent, includes TT, DT, Hepatitis B (rDNA) and Haemophilus type b conjugate vaccine (adsorbed). This method is rapid and can quantify both Triton X-100 and formaldehyde in a single preparation with improved peak asymmetry. This new assay has a linearity range starting from 0.0625 to 1 µg/mL for formaldehyde and 0.625-10 µg/mL for Triton X-100. This method would be very useful for viral vaccine manufacturing and release.

Optimization of aqueous two-phase micellar system for partial purification of L-asparaginase from Penicillium sp. grown in wheat bran as agro-industrial residue.

L-asparaginase has been used in the remission of malignant neoplasms such as acute lymphoblastic leukemia. The search for new sources of this enzyme has become attractive for therapeutics. Traditional methods for biomolecule purification involve several steps. A two-phase system may be a good strategy to anticipate one of these stages. This study aimed to produce and purify a fungal L-asparaginase through an aqueous two-phase micellar system (ATPMS) using Triton X-114. The fungus Penicillium sp.-encoded 2DSST1 was isolated from Cerrado soil. Plackett-Burman design followed by a 24 full factorial design was used to determine the best conditions to produce L-asparaginase. The evaluated variables were L-asparagine, L-proline, wheat bran, potato dextrose broth, ammonium sulfate, yeast extract, sucrose and glucose concentrations, incubation temperature, incubation period, and initial pH of the culture medium. L-asparaginase quantification was valued by the formation of ß-aspartyl hydroxamate. The significant positive variables, L-asparagine, L-proline, potato dextrose broth, and sucrose concentrations, were evaluated at 2 levels (+ 1 and - 1) with triplicate of the central point. After 34 runs, maximum activity (2.33 IU/mL) was achieved at the factorial design central point. A central composite design was performed in ATPMS at two levels (+ 1 and - 1) varying Triton X-114 concentration (w/v), separation phase temperature, and crude extract concentration (w/v). The L-asparaginase partition coefficient (K) was considered the experimental design response. Out of the 16 systems that were examined, the most promising presented a purification factor of 1.4 and a yield of 100%.

Consortia of bioactives in supercritical carbon dioxide extracts of mustard and small cardamom seeds lower serum cholesterol levels in rats: new leads for hypocholesterolaemic supplements from spices.

Melatonin-rich and 1,8-cineole-rich extracts have been successfully obtained from yellow mustard (YM) and small cardamom (SC) seeds, respectively, employing green technology of supercritical CO2 (SC-CO2) extraction. Chemical profiling confirmed the presence of melatonin and 1,8-cineole and co-extractants in the respective extracts. Electron paramagnetic resonance spectroscopy attested strong antioxidant activities of the extracts foregoing pan-assay interference compounds involved in spectroscopic analysis. These extracts also exhibited synergistic efficacies greater than unity confirming antioxidant synergy among the co-extracted bioactives therein. To ascertain hypocholesterolaemic efficacies, these extracts were co-administered orally with Triton X (at the pre-optimised dose of 175 mg/kg body weight (BW)) to Wistar albino rats at doses of 550, 175 and 55 mg/kg BW. Serum total cholesterol levels in the rats were monitored on days 3, 7, 15 and 21. On day 21, total cholesterol level reduced appreciably by 49·44 % in rats treated with YM seed extract and by 48·95 % in rats treated with SC seed extract, comparable with atorvastatin-administered rats (51·09 %). Either extract demonstrated inhibitory effects on hepatic 3-hydroxy-3-methyl-glutaryl-CoA (HMG-CoA) reductase activity. A molecular docking exercise identified specific compounds in the extracts which possessed binding affinities comparable with therapeutically used HMG-CoA reductase inhibitors. In silico and in vivo studies concertedly concluded that the consortium of bioactive components in the extracts cannot be considered as invalid metabolic panaceas and therefore these 'green' extracts could be safely subjected to clinical studies as preventive biotherapeutics for hypercholesterolaemia. These extracts could be consumed per se as hypocholesterolaemic supplements or could be ingredients of new spice-based therapeutic foods.

Analysis of Non-Ionic Surfactant Triton X-100 Using Hydrophilic Interaction Liquid Chromatography and Mass Spectrometry.

It is well known that surfactants increase the solubility of hydrophobic organic compounds and cause adverse environmental effects. The removal of these compounds from the contaminated soil or ground-water is particularly difficult due to their water soluble feature. In this work, an ultra-high performance hydrophilic interaction liquid chromatographic method was developed for the separation of oligomers of Triton X-100 octylphenol-polyethoxylate non-ionic surfactant. Liquid chromatography-mass spectrometry (LC-MS) was used to identify the Triton X-100 compounds. There was a 44 mass unit difference between two adjacent peaks that is the molar mass of one ethylene oxide group (⁻CH 2 CH 2 O⁻). A quadratic retention model was applied for the estimation of retention of the examined non-ionic surfactant and the optimization of gradient elution conditions. The optimized method was suitable for the baseline separation of 28 Triton X-100 oligomers in five minutes.

Alkaline hydrolysis to increase the selectivity of colorimetric determination of polysorbate.

Here, we describe a straightforward sample pretreatment step for the colorimetric cobaltthiocyanate determination of polysorbate, which circumvents the assay's shortcomings due to interference of protein and does not require complex instrumentation. Protein-containing test samples are hydrolyzed with strong alkali at 100 °C, neutralized and clarified by filtration before applying the colorimetric assay. The modified method performs with appropriate accuracy and precision, allowing specific polysorbate measurement in the presence of Triton X-100 during virus inactivation, determination of residual amounts of polysorbate in the final products and measurement of polysorbate 80 in final formulated products. The alkaline hydrolysis step, primarily designed to provide the assay's reliability in the presence of protein, also enhances its selectivity towards interference by the non-ionic detergent Triton X-100 and increases its robustness against changes in the fatty acid moiety of polysorbate as it released the fatty acid essentially contributing to the known heterogeneity of polysorbates. These results demonstrate that with sample pretreatment the handy colorimetric assay, not requiring complex instrumentation, can be used to measure polysorbate 80 concentrations in intermediates and final products of therapeutic protein solutions.

Enhanced production of erythritol and mannitol by Yarrowia lipolytica in media containing surfactants

Abstract Various chemical compounds, including surfactants, when introduced to culture media may increase the permeability of cellular membranes and thereby affect the quantity of metabolites excreted by cells. The aim of the present study was to evaluate the impact of detergents including Triton X-100, Span 20 and Tween 80 on erythritol production from glycerol by Yarrowia lipolytica Wratislavia K1 in a shake-flask experiment, batch and fed-batch cultures. When Span 20 was added to a fed-batch culture with glycerol as a carbon source (300 g L-1), erythritol production increased by 15% compared to the culture without the surfactant where it reached 142 g L-1 after 5 days, which corresponded to 0.47 g g-1 yield and productivity of 1.1 g L-1 h-1. Therefore, it was concluded that Span 20 considerably enhanced the production of this polyol from glycerol.

Enhanced production of erythritol and mannitol by Yarrowia lipolytica in media containing surfactants.

Various chemical compounds, including surfactants, when introduced to culture media may increase the permeability of cellular membranes and thereby affect the quantity of metabolites excreted by cells. The aim of the present study was to evaluate the impact of detergents including Triton X-100, Span 20 and Tween 80 on erythritol production from glycerol by Yarrowia lipolytica Wratislavia K1 in a shake-flask experiment, batch and fed-batch cultures. When Span 20 was added to a fed-batch culture with glycerol as a carbon source (300gL(-1)), erythritol production increased by 15% compared to the culture without the surfactant where it reached 142gL(-1) after 5 days, which corresponded to 0.47gg(-1) yield and productivity of 1.1gL(-1)h(-1). Therefore, it was concluded that Span 20 considerably enhanced the production of this polyol from glycerol.

Direct UV Spectrophotometry and HPLC Determination of Triton X-100 in Split Virus Influenza Vaccine.

One of the most commonly used surfactants in the production of split virus influenza vaccine is nonionic surfactant Triton X-100. After splitting of the virus is accomplished, Triton X-100 is removed from the vaccine by subsequent production steps. Because of toxicity of Triton X-100, which remains in the vaccine in residual amounts, a sufficiently sensitive method for its detection and quantification needs to be defined. Two methods for determination of Triton X-100 residuals were developed: the UV-spectrophotometry and HPLC methods. For both methods, preparation of vaccine samples and removal of proteins and virus particles were crucial: samples were treated with methanol (1:1) and then centrifuged at 25 000 × g for 30 min. After such treatment, the majority of vaccine components that interfered in the UV region were removed, and diluted samples could be directly measured. The chromatographic system included C18 column, step methanol gradient, and detection at 225 nm with a single peak of Triton X-100 at 12.6 min. Both methods were validated and gave satisfactory results for accuracy, precision, specificity, linearity, and robustness. LOQ was slightly lower for the HPLC method. Hence, it was shown that both methods are suitable for analysis of residual amounts of Triton X-100, with the advantages of the UV method being its simplicity and availability in most laboratories.

A novel method to determine residual detergent in biological samples post endotoxin reduction treatment and evaluation of strategies for subsequent detergent removal.

Endotoxin removal using detergent washes and extractions are well-established, efficient, and cost-effective methods; however, removing residual detergent post treatment has been shown to be a challenge. In this communication, we show a simple and fast method for determining the detergent concentration in a protein solution post treatment and highlight strategies for detergent removal to achieve levels below the critical micelle concentration (CMC), the minimum concentration at which detergent micelles form.

Laser desorption/ionization mass spectrometric analysis of folic acid, vancomycin and Triton® X-100 on variously functionalized carbon nanotubes.

RATIONALE: Carbon nanotubes (CNTs) have been ascertained to constitute versatile assisting matrices for laser desorption/ionization mass spectrometric analysis of different molecules. The functionalization thereof can lead to obtaining laser desorption/ionization assisting surfaces that would allow the detection of molecules at lower concentration and produce spectra with a better signal-to-noise ratio. METHODS: Pristine, -OH and -COOH functionalized multi-walled CNTs were obtained from commercial suppliers. Gallic or sinapinic acid was attached covalently to the CNT surfaces by forming an ester bond. Folic acid, vancomycin and Triton(®) X-100 were used as analytes to examine properties of these new assisting surfaces. Mass spectrometry analysis was conducted on a matrix-assisted laser desorption/ionization quadrupole time-of-flight (MALDIQTOF) mass spectrometer. RESULTS: The functionalization of CNTs was confirmed with Fourier transform infrared (FTIR) spectroscopy. The obtained mass spectra revealed that all the assisting surfaces are capable of transferring energy to the analytes; moreover, the presence of carboxyl groups in the structures of CNTs highly enhances their ionization properties. Nevertheless, the presence of sinapinic acid on CNT surfaces does not increase their properties to absorb pulse laser energy. CONCLUSIONS: The presented assisting surfaces are effective in LDI mass analysis of folic acid, vancomycin and Triton(®) X-100. The appropriate functionalization of CNTs can lead to the production of assisting surfaces that can become highly effective in the ionization of particular types of analytes.

Modeling of lead and cadmium uptake by plants in the presence of surfactants.

The mechanism of simultaneous uptake of Cd(II) and Pb(II) by Indian mustard (Brassica juncea) in presence of Triton X-100 and Tween 80 was investigated. The metal uptake data were analyzed according to the linear as well as the nonlinear Langmuir- and Freundlich-type models. The modeling efficiency (EF) and the root mean square error (RMSE) were used to evaluate the models prediction. Compared to the linear and the Langmuir-type models, the Freundlich-type model marginally exhibits a better fit for the biosorption of solubilized Cd(II) by surfactants as reflected by higher EF and lower RMSE values. The values of observed Pb(II) uptake were in close agreement with the predictions of the Freundlich-type model than for the Langmuir-type model.

Development and validation of a liquid chromatography method for simultaneous determination of three process-related impurities: yeastolates, triton X-100 and methotrexate.

Yeastolates, triton X-100 (TX-100) and methotrexate (MTX) are common process-related impurities (PRI) in cell-based bioproduction of many active biopharmaceuticals. In this study, a reverse phase high performance liquid chromatography (RP-HPLC) method coupled with ultraviolet (UV) detection was developed for simultaneous determination and quantitation of these impurities. The chromatographic separation was achieved using a Jupiter C4 column and analyses of yeastolates, TX-100 and MTX were monitored at 257, 280 and 302 nm, respectively. The method was further validated with respect to selectivity, linearity, limit of detection (LOD), limit of quantitation (LOQ), precision and accuracy. The limits of quantitation for yeastolates, TX-100 and MTX were determined to be 27 ppm, 10 ppm and 41 ppb, respectively. Finally, the suitability of the method for analyses of recombinant human hyaluronidase (rHuPH20) in-process (viral inactivation, QFF, PS, APB and CHT filtered, final viral filtrate) and final manufacturing materials was demonstrated, and trace levels of yeastolates, TX-100 and MTX were reliably measured except for three matrices early in the purification process in which TX-100 was not accurately determined due to interfering effects.

Rapid determination of surfactant critical micelle concentration in aqueous solutions using fiber-optic refractive index sensing.

We describe a simple and rapid method for determining the critical micelle concentration (CMC) of surfactants from fiber-optic measurements of refractive index. The refractive index of an aqueous surfactant solution was monitored as the surfactant concentration was increased using an automated dispensing system. On reaching the surfactant's CMC value, an abrupt change was observed in the rate of increase of the refractive index with increasing concentration. The measurement system provides rapid semiautomatic data collection and analysis, increasing the precision, sensitivity, and range of applicability of the technique while substantially decreasing the amount of manual intervention required. Measurements of CMC for sodium dodecyl sulfate (8.10mM), cetyltrimethylammonium chloride (1.58mM), and Triton X-100 (0.21mM) were in excellent agreement with values previously reported in the literature. The method is applicable to cationic, anionic, and nonionic surfactants, and it offers a facile, in situ, and sensitive means of detecting micelle formation over a broad range of CMC values larger than 10(-1)mM.

Solvent-detergent filtered (S/D-F) fresh frozen plasma and cryoprecipitate minipools prepared in a newly designed integral disposable processing bag system.

Solvent-detergent (S/D) viral inactivation was recently adapted to the treatment of single plasma donations and cryoprecipitate minipools. We present here a new process and a new bag system where the S/D reagents are removed by filtration and the final products subjected to bacterial (0.2 microm) filtration. Recovered and apheresis plasma for transfusion (FFP) and cryoprecipitate minipools (400 +/- 20 mL) were subjected to double-stage S/D viral inactivation, followed by one oil extraction and a filtration on a S/D and phthalate [di(2-ethylhexyl) phthalate (DEHP)] adsorption device and a 0.2 microm filter. The initial and the final products were compared for visual appearance, blood cell count and cell markers, proteins functional activity, von Willebrand factor (VWF) multimers and protein profile by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Tri (n-butyl) phosphate (TnBP) was quantified by gas chromatography and Triton X-45 and DEHP by high-performance-liquid chromatography (HPLC). General safety tests were by 6.5 mL/kg intravenous injection in rats. The treated plasmas and cryoprecipitates were very clear and the protein content and functionality, VWF multimers and SDS-PAGE profiles were well preserved. TnBP and Triton X-45 were < 1 and <25 ppm, respectively, and DEHP (about 5 ppm) was less than it was in the starting materials. Blood cell counts and CD45, CD61 and glycophorin A markers were negative. There was no enhanced toxicity in rats. Thus, plasma and cryoprecipitate can be S/D-treated in this new CE-marked disposable integral processing system under conditions preserving protein function and integrity, removing blood cells, S/D agents and DEHP, and ensuring bacterial sterility. This process may offer one additional option to blood establishments for the production of virally inactivated plasma components.

[Spectral analyses during the isolation course of Spirulina platensis phycobilisomes using low-speed centrifugation].

The phycobilisomes were isolated from Spirulina platensis using low-speed centrifugation. The crude phycobilisomes solution extracted by Triton X-100 was centrifugated (13000 rpm) four times. The centrifugated phycobilisomes solution was spectrally analyzed using absorption spectrum each time. The absorption spectrum showed that the ultraviolet absorption maximum of the phycobilisomes solution was still at 263 nm, and also exhibited the characteristic chlorophyllous absorption in the rang of 400-450 nm after the fourth centrifugation. This indicated that there existed small quantities of Triton X-100 and chlorophyll in the centrifugated phycobilisomes solution. But the ultraviolet absorption maximum was red-shifted to 277 nm and the chlorophyllous absorption was not observed in the absorption spectrum of the phycobilisomes solution obtained by high concentration salt precipitation, which meant that the method of high concentration salt precipitation could effectively remove Triton X-100 and chlorophyll from the phycobilisomes solution. The precipitated phycobilisomes of Spirulina platensis were further purified by using Sepharose CL-6B column chromatography. The fluorescence emission maximum of the purified phycobilisomes at room temperature was at 680 nm, which indicated that the purified phycobilisomes were intact.