Preparation and characterization of ternary polysaccharide hydrogels based on carboxymethyl cellulose, carboxymethyl chitosan, and carboxymethyl ß-cyclodextrin.

A series of ternary polysaccharide hydrogels were facile prepared by incorporating carboxymethyl cellulose (CMC) into the carboxymethyl chitosan/carboxymethyl ß-cyclodextrin (CMCS/CMCD) complex solution based on multiple physical interactions. Structure properties of the CMC/CMCS/CMCD hydrogels were revealed by FTIR, XRD, SEM, and TG. The rheological and texture properties, temperature/pH-response behaviors, biocompatablity, and antimicrobial activity of the hydrogels were determined in detail. These results showed that the existence of electron force and hydrogen bond among three components leading to formation of the hydrogels, displaying good mechanical characteristic, stable solid-like rheological properties, controllable swelling and degradation behaviors, and excellent biocompatibility. Additionally, the swelling kinetics can be well described by the Schott's pseudo second order model. Moreover, the hydrogels loaded with cinnamic acid (CA) exhibited good antimicrobial activity against both Staphylococcus aureus and Escherichia coli, and the antimicrobial activity was related to the composition of the prepared hydrogels. The novel ternary polysaccharide hydrogels may have good application prospects in food and bio-medicine.

Fabrication of immobilized lipases for efficient preparation of 1,3-dioleoyl-2-palmitoylglycerol.

This study aims to fabricate immobilized lipases for efficient preparation of 1,3-dioleoyl-2-palmitoyl-glycerol (OPO) through acidolysis of glycerol tripalmitate (PPP). Twelve (three types) supports and five lipases were studied carefully. Among them, the immobilized Thermomyces lanuginosa lipase (TLL) samples exhibited overall better performance than that of other immobilized lipases. Particularly, organic groups functionalized SBA-15 (R-SBA-15) supported TLL (TLL@R-SBA-15) samples gave PPP conversion from 97.70 to 99.00 % and OPO content from 59.52 to 64.73 %. After optimization, PPP conversion up to 99.07 %, OPO content 73.15 % and sn-2 palmitic acid content 90.09 % were obtained with TLL@C18H37-SBA-15 as catalyst. Moreover, TLL@C18H37-SBA-15 exhibited better acidolysis performance from 50 °C than that from 60 to 80 °C, which helped inhibit acyl migration. In addition, after 5 cycles of reuse, TLL@C18H37-SBA-15 retained 81.04 % (based on OPO content) and 98.88 % (based on sn-2 palmitic acid content) of its initial activity, indicating it had an attractive prospect in future applications.

Immobilization of Candida antarctica Lipase A onto Macroporous Resin NKA-9: Esterification and Glycerolysis Performance Study.

In this study, lipase A from Candida antarctica (CALA) was immobilized onto the macroporous resin NKA-9. Immobilization conditions (pH, time and CALA concentration) were studied, enzymatic activity and immobilization efficiency (IE) up to 968.89 U/g and 53.19% were respectively obtained under optimal conditions (immobilization pH 5.0, time 5 h and CALA concentration at 30 mg/mL). Then, the NKA-9 supported CALA (CALA@NKA-9) samples were used to catalyze glycerolysis in solvent-free system. With 0.25 g of the present CALA@NKA-9 (soybean oil 3.52 g and glycerol 0.184 g) and after 12 h reaction at 50 °C, diacylglycerols (DAG) content up to 64.37% and triacylglycerols (TAG) conversion at 83.33% were obtained. The relationship between temperature and TAG conversion was LnV 0 = 13.9310-6.4212/T for CALA@NKA-9. Meanwhile, the activation energy (Ea) of CALA@NKA-9 was calculated to be 53.39 kJ/mol. In addition, reusability in the glycerolysis reaction was also evaluated, and 57.82% of the initial glycerolysis activity was retained after 9 consecutive applications. Furthermore, the CALA@NKA-9 was also used to catalyze the esterification (esterification of fatty acids with glycerol), however, the present CALA@NKA-9 cannot initiate the esterification. Therefore, the present CALA@NKA-9 is shown to be potential for DAG production through glycerolysis reaction.

Immobilization of Lecitase® Ultra onto the Organic Modified SBA-15 for Soybean Oil Degumming.

In this study, SBA-15 was functionalized by organic groups (-CH3, -C4H9, -C8H17, -CH2CH2NH2, -C6H5, et al.), and then Lecitase® Ultra (LU) was immobilized onto the modified SBA-15 for soybean oil degumming. The hydrolysis activity, degumming performance, reusability in degumming, and the composition of phospholipids in the gum, of the immobilized LU samples, were carefully studied. Hydrolysis activities over 1800 U/g were obtained from all the immobilized LU samples. The highest activity of up to 4554.17 U/g was observed from the 3-ureidopropyl group-modified SBA-15-supported LU. Most of the immobilized LU samples removed the phospholipids effectively from crude soybean oil (initial phosphorous content 314.23 mg/kg), with a residual phosphorus content of less than 10 mg/kg. The reusability of the immobilized LU samples in the degumming process was evaluated. No loss of activity was observed from the methyl and N-(2-aminoethyl)-3-aminopropyl group-modified SBA-15-supported LU samples after five cycles of reuse. In addition, 3-aminopropyl and 3-glycidyloxypropyl group-modified SBA-15-supported LU samples retained over 90% of their initial activity; N-phenylaminomethyl and 1-isocyanatopropane group-functionalized SBA-15-supported LU samples retained approximately 80% of their initial activity. The phospholipids in the gum were analyzed. The n-octadecyl and N-(2-aminoethyl)-3-aminopropyl group-functionalized SBA-15-supported LU samples were selective for lysophosphatidylethanolamine (LPE) preparation, and LPE percentages up to 37.14 and 38.80% were obtained, respectively. The N-phenylaminomethyl group-modified SBA-15-supported LU showed selectivity toward lysophosphatidylcholine (LPC) production, with an LPC percentage of up to 38.5%.

Encapsulation of lipases by nucleotide/metal ion coordination polymers: enzymatic properties and their applications in glycerolysis and esterification studies.

BACKGROUND: In the present study, lipases of TLL (lipase from Thermomyces lanuginosus), AOL (lipase from Aspergillus oryzae), RML (lipase from Rhizomucor miehei), BCL (lipase from Burkholderia cepacia), CALA (Candida antarctica lipase A) and LU (Lecitase® Ultra) were encapsulated into nucleotide-hybrid metal coordination polymers (CPs). Enzyme concentration was optimized for encapsulation and the enzymatic properties of the obtained lipases were investigated. In addition, their performance in glycerolysis and esterification was evaluated, and glycerolysis conditions (water content, temperature and time) were optimized. RESULTS: Hydrolysis activity over 10 000 U g-1 and activity recovery over 90% were observed from AOL@GMP/Tb, TLL@GMP/Tb and RML@GMP/Tb. GMP/Tb encapsulation (of AOL, TLL, RML and LU) improved their thermostability when incubated in air. The encapsulated lipases exhibited moderate [triacylglycerols (TAG) conversion 30-50%] and considerable glycerolysis activity (TAG conversion over 60%). TAG conversions from 69.37% to 82.35% and diacylglycerols (DAG) contents from 58.62% to 64.88% were obtained from CALA@GMP/metal samples (except for CALA@GMP/Cu). Interestingly, none of the encapsulated lipases initiated the esterification reaction. AOL@GMP/Tb, TLL@GMP/Tb, RML@GMP/Tb and CALA@GMP/Tb showed good reusability in glycerolysis, with 88.80%, 94.67%, 89.85% and 78.16% of their initial glycerolysis activity, respectively, remaining after five cycles of reuse. The relationships between temperature and TAG conversion were LnV0  = 6.5364-3.7943/T and LnV0  = 13.8820-6.4684/T for AOL@GMP/Tb and CALA@GMP/Tb, respectively; in addition, their activation energies were 31.55 and 53.78 kJ mol-1 , respectively. CONCLUSION: Most of the present encapsulated lipases exhibited moderate and considerable glycerolysis activity. In addition, AOL@GMP/Tb, TLL@GMP/Tb, RML@GMP/Tb and CALA@GMP/Tb exhibited good reusability in glycerolysis reactions and potential in practical applications. © 2022 Society of Chemical Industry.

Encapsulation of CALB by nucleotide/metal ions coordination nanoparticles: highly selective catalysis of esterification while poor performance in glycerolysis reaction.

BACKGROUND: Enzymatic esterification is attracting for particular high-acid oil deacidification. In this study, Candida antarctica lipase B (CALB) was encapsulated into a series of nucleotide-hybrid metal coordination polymers (CPs), which were constructed by guanosine 5'-monophosphate (GMP) and various metals. RESULTS: We here found that, most of the present CPs encapsulated CALB (CALB@CPs) samples were highly selective for esterification while poor in glycerolysis reaction. They exhibited quite poor performance in glycerolysis, with triacylglycerols (TAGs) conversion lower than 5%, despite this considerable enzymatic hydrolysis activities were observed. However, they (most of them) showed good performance in esterification of fatty acids and glycerol for TAG synthesis. In addition, the GMP/Tb (CPs constructed by GMP and Tb3+ ) encapsulated CALB (CALB@GMP/Tb) transformed over 98% of oleic acid into glycerides in the high-acid oil deacidification process, and TAG content from 87 to 89% was obtained. Moreover, the CALB@GMP/Tb showed good reusability in the esterification system. CONCLUSION: The present CALB@CPs samples are selective for esterification and suitable for high-acid oils deacidification. This work provides a new system for enzymatic selectivity improvement study. © 2021 Society of Chemical Industry.

Effects of Solvents on the Glycerolysis Performance of the SBA-15 Supported Lipases.

In this study, Candida antarctica lipase B (CALB), Rhizomucor miehei lipase (RML) and Lecitase® Ultra (LU) were immobilized onto the mesoporous silica SBA-15. The glycerolysis performance of the obtained supported lipases (lipase@SBA-15) in solvent systems was carefully investigated. LU@SBA-15 exhibited good glycerolysis performance in solvent-free system, with diacylglycerols (DAG) content and triacylglycerols (TAG) conversion at 52.4 and 98.6% respectively obtained after 12 h reaction at 60°C. CALB@SBA-15 showed good glycerolysis activity in tert-pentanol and tert-butanol systems, with TAG conversion over 90% obtained. In addition, the present CALB@SBA-15 exhibited selectivity for monoacylglycerols (MAG) production, with glycerol to TAG molar ratio increased to 3:1, MAG content over 80% and TAG conversion over 99% could be obtained from both tert-pentanol and tert-butanol systems. However, RML@SBA-15 showed low glycerolysis activity neither in solvent nor in solvent-free systems. The present results favor the practical enzymatic design for MAG and DAG production.

Immobilization of lipases onto the halogen & haloalkanes modified SBA-15: Enzymatic activity and glycerolysis performance study.

In this study, SBA-15 was modified by halogen & haloalkanes and later used to immobilize lipases. The hydrolysis activity and the glycerolysis performance of the immobilized lipases was carefully studied. Highest activity of the immobilized Candida antarctica lipase B (CALB), Lipase from Aspergillus oryzae (AOL), Lecitase® Ultra (LU) and lipase from Rhizomucor miehei (RML) was respectively at 5577, 12000, 2822 and 11,577 U/g; in addition, the highest activity was obtained from the lowest or moderate lipase loading, at 25.73, 90.72, 89.52 and 30.56 mg/g respectively. The mechanism of lipase immobilization was studied and it was through interfacial activation. The halogen & haloalkanes modification of SBA-15 afforded considerable glycerolysis activity for diacylglycerols (DAG) preparation. CALB@SBA-15-CH2CH2(CF2)5CF3 and CALB@SBA-15-CH2CH2(CF2)7CF3 were suitable for DAG production, they both exhibited good reusability in glycerolysis reaction, with 117.36% and 93.06% of their initial glycerolysis activity retained respectively after ten cycles of reuse. The relationships between temperature with triacylglycerols (TAG) conversion were lnV0 = 3.13-3.07/T and lnV0 = 7.90-4.64/T respectively for CALB@SBA-15-CH2CH2(CF2)5CF3 and CALB@SBA-15-CH2CH2(CF2)7CF3; in addition, their activation energy (Ea) was respectively at 25.50 and 38.54 kJ/mol.

Organic Modifications of SBA-15 Improves the Enzymatic Properties of its Supported TLL.

In this study, lipase from Thermomyces lanuginosus (TLL) was immobilized onto the parent and organic groups modified SBA-15, and the enzymatic properties of the obtained immobilized TLL samples were investigated. 1) Activity of SBA-15-TLL at 2862.78 ± 293.24 U/g was obtained. 2) Most of the organic groups modification favored a great improvement in activity, and higher activity over 12000 U/g was observed for N-phenylaminomethyl and phenyl group modification. 3) Most of the supported TLL showed better thermostability in air while poor in phosphate buffer, with over 80% vers less than 20% of their initial activity retained after 4 h incubation at 70℃. 4) The n-dodecyl, phenyl and N-phenylaminomethyl group functionalization decreased the sensitivity of immobilized TLL in extreme pH values. 5) The n-octyl and 2-(propoxymethyl)oxirane group modification confered the supported TLL good reusability, and over 60% of their initial activity was retained after five successive cycles of reuse.

Immobilization of Lecitase® Ultra onto the Amino-functionalized SBA-15 and their Applications in Glycerolysis.

In this study, Lecitase® Ultra (LU) was immobilized onto the parent and the amino-functionalized SBA-15. The immobilization conditions were studied and the activity of the parent SBA-15 supported LU (SBA-15-LU) was found to be at 2177.78 ± 101.84 U/g. After 3-aminopropyl and n-(2-aminoethyl)-3-aminopropyl groups functionalization, enzymatic activity was increased to 3555.56 ± 200.21 and 3444.44 ± 346.41 U/g respectively. The immobilized LU samples were then used to catalyze glycerolysis. The possibility for diacylglycerols (DAG) and monoacylglycerols (MAG) production was evaluated and it was found only suitable for DAG production. In addition, the glycerolysis activity of the immobilized LU was impaired by the tert-pentanol and solvent-free was found suitable. Similar DAG content over 50 wt% could be obtained from glycerolysis by the three immobilized LU samples. The reusability in glycerolysis was evaluated, and 9.79 % of the initial glycerolysis activity was remained from the SBA-15-LU after 5 cycles of reuse. Encouragingly, after 3-aminopropyl and n-(2-aminoethyl)-3-aminopropyl groups functionalization, 62.93 and 83.91% of their initial activity was respectively remained after 5 cycles of reuse.

Production of diacylglycerols through glycerolysis with SBA-15 supported Thermomyces lanuginosus lipase as catalyst.

BACKGROUND: In this study, SBA-15 was functionalized by silane coupling reagents, then lipase from Thermomyces lanuginosus (TLL) was immobilized onto the parent and the organically modified SBA-15 for diacylglycerol (DAG) production through glycerolysis. RESULTS: Diacylglycerol content of 54.77 ± 0.63%, and triacylglycerol (TAG) conversion of 77.75 ± 1.24%, were obtained from the parent SBA-15 supported TLL-mediated glycerolysis reaction in a solvent-free system. However, poor performance was unexpectedly observed when co-solvents were introduced into the reaction system. After organic modification, the functionalized SBA-15 supported TLL samples all exhibited reasonable performance, producing DAG content over 40 wt% and TAG conversion over 70 wt%. Higher DAG content, up to 59.19 ± 1.10%, was observed from the phenyl group-modified SBA-15 supported TLL. The operational stability of the immobilized TLL samples in glycerolysis was also improved after organic functionalization. The phenyl group-modified SBA-15 supported TLL showed good reusability in the present glycerolysis reaction, and 95.21 ± 4.87% of the initial glycerolysis activity remained after five cycles of reuse. CONCLUSION: The organic modification of SBA-15 improved the catalytic performance of its supported TLL in glycerolysis, in terms of TAG conversion, DAG content, and reusability. © 2019 Society of Chemical Industry.

Immobilization of Rhizomucor miehei lipase onto the organic functionalized SBA-15: Their enzymatic properties and glycerolysis efficiencies for diacylglycerols production.

In this study, mesoporous silica SBA-15 was modified by organic functional groups through silanization. Series of organosilane compounds were grafted onto the SBA-15, and the obtained functionalized carriers were then used to immobilize the lipase from Rhizomucor miehei (RML). The enzymatic properties of the obtained immobilized RML samples were evaluated, and the catalytic efficiencies in glycerolysis of triacylglycerols (TAG) reaction were studied. Compared with the parent SBA-15 immobilized RML, the organic modification gave a maximum improvement of enzymatic activity from 200.00 to 13211.11 U/g; in addition, TAG conversion and diacylglycerols (DAG) content increased from 21.28 to 84.24% and 15.45 to 59.03% respectively. The organic modification also decreased the sensitivity of immobilized RML in extreme pH values and increased their thermostability.

Immobilization of Candida antarctica Lipase B onto organically-modified SBA-15 for efficient production of soybean-based mono and diacylglycerols.

In this study, SBA-15 was modified by a series of silane coupling reagents and later used to immobilize Candida antartica lipase B (CALB). The enzymatic properties of the immobilized CALB samples were studied. In addition, the catalytic performance in glycerolysis of soybean oil for diacylglycerols (DAG) production was also investigated. The highest enzymatic activity up to 6100.00 ±â€¯246.41 U/g was observed from the propyl methacrylate group modified SBA-15 supported CALB. No loss of activity was observed from the propyl methacrylate group modified SBA-15 supported CALB, but a higher-than-initial activity was notably found from 3-aminopropyl group and n-octyl group modified SBA-15 supported CALB after a 4-h incubation in air at 70 °C. 1-isocyanatopropane group modified SBA-15 supported CALB exhibited selectivity for DAG production. DAG content up to 61.90 ±â€¯2.38 wt% and a DAG/MAG ratio at 3.11 ±â€¯0.08 was obtained after a 24-h reaction at 60 °C in a solvent-free system.

Immobilization of Candida antarctica lipase B onto SBA-15 and their application in glycerolysis for diacylglycerols synthesis.

In this study, Candida antarctica lipase B (CALB) was immobilized on SBA-15 with three pore diameters. CALB loading was found increased with CALB concentration increasing from 20.3 to 80.12µg/ml. Higher CALB loading was observed from SBA-15 with pore diameters at 8.1nm (SBA-15(8.1)), yet highest hydrolytic activity was found at SBA-15(12.5). Thermal stability of the immobilized CALB (SBA-15-CALB) samples was greatly influenced by their water content, after 4h storage at 70°C, 8.93 and 67.4% of the initial activity was observed from SBA-15-CALB samples with water content at 9.23 and 3.22% respectively. The SBA-15-CALB samples were then used in glycerolysis of corn oil, and 53.6wt% of diacylglycerols was obtained after optimization. The operational stability was tested, and after 5 consecutive applications, 92.5 and 80.3% of the initial glycerolysis activity was remained respectively from SBA-15(6.6)-CALB and SBA-15(12.5)-CALB.

[Study on the Conformation of Soybean Selenoprotein Solution with Spectroscopy Methods].

The structure characteristic of soybean selenoprotein and soy protein isolate (SPI) were investigated with fluorescence, ultraviolet and Fourier transform infrared (FTIR) spectrum. The unfolding process of two proteins was analyzed with fluorescence phase diagram method. The stability of emulsion properties and the influence of concentration, temperature and pH on the conformation of soy selenoproteins were also determined. The results indicated that the covalent disulfide bond of soybean selenoprotein molecules was damaged; the hydrogen bonding become weak; the hydrophobic interactions were enhanced and the protein chain molecules were extended. Soybean selenoprotein displayed only "folding" and "loose" state in solution, which illustrated soybean selenoprotein more tend to hydrolysis when compared with soybean protein. With temperature increasing, the fluorescence quenching effect occurred and the hydrophobicity of soy selenoproteins was also gradually increased, which reflected the protein molecules tends to be folded. In the range of pH 2.8～8.0, the Trp residue of soybean selenoprotein was mainly distributed in the polarity of the external environment and presented different conformational change on both sides of the isoelectric point under different pH value. In acidic environment, the soybean selenoprotein was easy to appear conformational transition from loose to fold. But it was conducive for soybean selenoprotein to existence in loose structure in alkaline conditions. In addition, the emulsifying properties of soybean selenoprotein were analyzed based on UV spectral data. Results showed that lower temperature helps to enhancement the emulsification but unfavorable the stability of the soybean selenoprotein.

Synthesis, characterization, in vitro cytotoxicity, and apoptosis-inducing properties of ruthenium(II) complexes.

Two new Ru(II) complexes, [Ru(bpy)2(FAMP)](ClO4)2 1 and 2, are synthesized and characterized by elemental analysis, electrospray mass spectrometry, and 1H nuclear magnetic resonance. The in vitro cytotoxicities and apoptosis-inducing properties of these complexes are extensively studied. Complexes 1 and 2 exhibit potent antiproliferative activities against a panel of human cancer cell lines. The cell cycle analysis shows that complexes 1 and 2 exhibit effective cell growth inhibition by triggering G0/G1 phase arrest and inducing apoptosis by mitochondrial dysfunction. The in vitro DNA binding properties of the two complexes are investigated by different spectrophotometric methods and viscosity measurements.

Solvent-free enzymatic synthesis of 1, 3-diacylglycerols by direct esterification of glycerol with saturated fatty acids.

BACKGROUND: Pure 1, 3-diacylglycerols (1, 3-DAG) have been considered to be significant surfactants in food, cosmetics and pharmaceutical industries, as well as the effect on obesity prevention. METHODS: In this study, a vacuum-driven air bubbling operation mode was developed and evaluated for the enzymatic synthesis of 1, 3-DAG of saturated fatty acids, by direct esterification of glycerol with fatty acids in a solvent-free system. The employed vacuum-driven air bubbling operation mode was comparable to vacuum-driven N2 bubbling protocol, in terms of lauric acid conversion and 1, 3-dilaurin content. RESULTS: Some operation parameters were optimized, and 95.3% of lauric acid conversion and 80.3% of 1, 3-dilaurin content was obtained after 3-h reaction at 50°C, with 5 wt% of Lipozyme RM IM (based on reactants) amount. Of the lipases studied, both Lipozyme RM IM and Novozym 435 exhibited good performance in terms of lauric acid conversion. Lipozyme TL IM, however, showed low activity. Lipozyme RM IM showed good operational stability in this operation protocol, 80.2% of the original catalytic activity remained after 10 consecutive batch applications. Some other 1, 3-DAG were prepared and high content was obtained after purification: 98.5% for 1, 3-dicaprylin, 99.2% for 1, 3-dicaprin, 99.1% for 1, 3-dilaurin, 99.5 for 1, 3-dipalmitin and 99.4% for 1, 3-disterin. CONCLUSION: The established vacuum-driven air bubbling operation protocol had been demonstrated to be a simple-operating, cost-effective, application practical and efficient methodology for 1, 3-DAG preparation.

Development and evaluation of reverse-transcription loop-mediated isothermal amplification for rapid detection of human immunodeficiency virus type 1.

PURPOSE: The objective of this study was to establish a reverse-transcription loop-mediated isothermal amplification (RT-LAMP) method for rapid detection of human immunodeficiency virus type 1 (HIV-1). MATERIALS AND METHODS: The HIV-1 integrase gene region was selected because it was a conserved part of the HIV-1 genome. Six primers specific to eight regions of the HIV-1 integrase gene were designed. A total of 171 samples (18 HIV-1 confirmed positive samples and 153 serum specimens were collected in this study) were tested by RT-LAMP and reverse-transcription polymerase chain reaction (RT-PCR). After amplification in an isothermal water bath for 45 min, samples containing HIV-1 generated the expected ladder-like products while other viruses generated no product. RESULTS: The sensitivity and specificity of the RT-LAMP assay were evaluated by comparison with RT-PCR. The assay was significantly more sensitive than normal gel-based RT-PCR. CONCLUSION: Because it is specific and simple, the RT-LAMP assay can be widely applied in clinical laboratories for rapid detection of HIV-1.

Synthesis, characterization, cellular uptake, apoptosis, cytotoxicity, dna-binding, and antioxidant activity studies of ruthenium(II) complexes.

Two new ruthenium(II) polypyridyl complexes [Ru(dmb)(2)(HECIP)](ClO(4))(2) (1) (HECIP = N-ethyl-4-[(1,10)-phenanthroline(5,6-f)imidazol-2-yl]carbazole, dmb = 4,4'-dimethyl-2,2'-bipyridine) and [Ru(dmp)(2)(HECIP)](ClO(4))(2) (2) (dmp = 2,9-dimethyl-1,10-phenanthroline) have been synthesized and characterized. The DNA-binding behaviors of the two complexes were investigated by absorption spectra, viscosity measurements, and photoactivated cleavage. The DNA-binding constants for complexes 1 and 2 were determined to be 8.03 (± 0.12) × 10(4) M(-1) (s = 1.62) and 2.97 (± 0.15) × 10(4) M(-1) (s = 1.82), respectively. The results suggest that these complexes interact with DNA through intercalative mode. The photocleavage of pBR322 DNA by Ru(II) complexes was investigated. The cytotoxicity of complexes 1 and 2 has been evaluated by the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide)] method. Complex 1 shows higher anticancer potency than 2 against the four tumor cell lines. Apoptosis and cellular uptake were investigated. The antioxidant activities of the ligand and these complexes were also performed.

Study of the factors affecting the extraction of soybean protein by reverse micelles.

In this work, the forward and back extraction of soybean protein by reverse micelles was studied. The reverse micellar systems were formed by anionic surfactant sodium bis(2-ethyl hexyl) sulfosuccinate (AOT), isooctane and KCl solution. The effects of AOT concentration, aqueous pH, KCl concentration and phase volume ratio on the extraction efficiency of soybean protein were tested. Suitability of reverse micelles of AOT and Triton-X-100/AOT mixture in organic solvent toluene for soybean protein extraction was also investigated. The experimental results lead to complete forward extraction at the AOT concentration 120 mmol l(-1), aqueous pH 5.5 and KCl concentration 0.8 mol l(-1). The backward extraction with aqueous phase (pH 5.5) resulted in 100% extraction of soybean protein from the organic phase.