Curcumin and silver nanoparticles loaded antibacterial multifunctional pectin/gelatin films for food packaging applications.

Renewable biomass-based materials have a huge potential to replace petroleum-based products in food packaging. Herein, pectin/gelatin films loaded with curcumin and silver nanoparticles (AgNPs) are prepared by solution-pouring technology to serve as antimicrobial multifunctional food packaging films. AgNPs and curcumin are found to equally distribute in the films. Fourier transform infrared spectroscopy (FT-IR) reveal the hydrogen bonding and electrostatic interaction among curcumin, AgNPs, pectin and gelatin. The composite films show good antioxidant activity, mechanical performance, hydrophobicity and antibacterial ability. The films of P-GCA 0.5 showed 99.57 ± 0.16 % and 100 % inhibition against E. coli and S. aureus, respectively. The films also demonstrate excellent water vapor barrier qualities. In addition, the composite films possess pH-responsive color change behaviors from yellow (pH 3-8) to light red (pH 8-9) to dark red (pH 11-12), which is suitable for monitoring the freshness of shrimp packaging based on pH changes during deterioration process. As sustainable biomass-based materials, the multifunctional composite films are promising in intelligent food packaging applications.

Enhanced extraction of astaxanthin using aqueous biphasic systems composed of ionic liquids and potassiumphosphate.

Shrimp waste containing a substantial amount of valuable nutrients presents a challenge for food industry. In this work, extraction of astaxanthin from shrimp waste via aqueous biphasic systems (ABS) composed of ionic liquids (ILs) and potassiumphosphate (K3PO4) was investigated. The influence of phosphonium- and ammonium-based ILs and temperature on the phase behavior and astaxanthin extraction was evaluated. The hydrogen-bond basicity of each IL studied shows a negative linear correlation with tie-line lengths of ABS and a positive linear correlation with extraction efficiency (EEAst). In general, lower temperature are favourable for astaxanthin extraction. Tributyloctylphosphonium bromide ([P4448]Br) resulted in the strongest ABS formation ability and bonding interactions between the anion and astaxanthin. Compared with organic solvents, [P4448]Br + K3PO4 ABS achieved higher EEAst of 93.08% at 308 K. The chemical properties provide the possibility of prescreening appropriate ILs for ABS formation and predicting the partition of a target molecule.

Down-regulation of LHPP in cervical cancer influences cell proliferation, metastasis and apoptosis by modulating AKT.

Cervical cancer is a leading severe malignancy throughout the world. Though various pathologies associated with cervical cancer progression have been demonstrated, further study is still necessary to reveal the tumorigenesis of cervical cancer. The protein histidine phosphatase LHPP is reported as a tumor suppressor. Histidine phosphorylation, also known as hidden phosphoproteome, is a poorly characterized post-translational modification of proteins. LHPP is evolutionarily conserved from worm to human. In the present study, we discovered that LHPP expression levels were lower in human cervical cancer tumors than that in adjacent normal tissue samples. LHPP expression levels were also reduced in several cervical cancer cell lines. Further, LHPP over-expression reduced the cell proliferation, migration and invasion, associated with the change of p53 and metastasis signaling pathways. Moreover, over-expressing LHPP markedly induced apoptosis in human cervical cancer cells via promoting the cleaved Caspse-3 and PARP. Importantly, we found that LHPP over-expression blocked AKT activation. Elevating AKT activity could abolish the role of LHPP over-expression in reducing cell proliferation and metastasis, as well as in inducing apoptotic response. Moreover, suppressing p53 expression with its inhibitor of PFTα abrogated the activity of LHPP to impede cell proliferation and metastasis, and to trigger apoptosis. AKT phosphorylation also restrained p53 expression levels in cervical cancer cells. In vivo, the anti-cervical cancer effects of LJPP were verified, which were also via the repression of cell proliferation and metastasis, and the induction of apoptosis. Therefore, LHPP could be considered as an effective candidate to develop effective therapeutic strategy against cervical cancer development.

One-pot synthesis of magnetic colloidal nanocrystal clusters coated with chitosan for selective enrichment of glycopeptides.

Selective enrichment of glycopeptides prior to the mass spectrometry (MS) analysis is essential due to ion suppression effect during ionization caused by the co-presence of non-glycosylated peptides. Among the enrichment approaches, hydrophilic interaction liquid chromatography (HILIC) based on magnetic separation has become a popular method in recent years. As the conventional synthesis procedures of these materials are tedious and time-consuming with at least four steps. Herein, magnetic colloidal nanocrystal clusters coated with chitosan (Fe3O4@CS MCNCs) have been successfully prepared by a simple one-pot method. The resulting Fe3O4@CS MCNCs demonstrated an excellent ability for glycopeptide enrichment with high selectivity, low detection limit and high binding capacity. Furthermore, in the analysis of real complicated biological sample, 283 unique N-glycosylation sites corresponding to 175 glycosylated proteins were identified in three replicate analyses of 45µg protein sample extracted from HeLa cells, indicating the great potential in detection and identification of low abundant glycopeptides in glycoproteome analysis.

Facile preparation of core-shell magnetic metal-organic framework nanospheres for the selective enrichment of endogenous peptides.

Facile preparation of core-shell magnetic metal-organic framework nanospheres by a layer-by-layer approach is presented. The nanospheres have high surface area (285.89 cm(2) g(-1)), large pore volume (0.18 cm(3) g(-1)), two kinds of mesopores (2.50 and 4.72 nm), excellent magnetic responsivity (55.65 emu g(-1)), structural stability, and good dispersibility. The combination of porosity, hydrophobicity, and uniform magnetism was exploited for effective enrichment of peptides with simultaneous exclusion of high molecular weight proteins. The nanospheres were successfully applied in the selective enrichment of endogenous peptides in human serum.

Ti4+-immobilized multilayer polysaccharide coated magnetic nanoparticles for highly selective enrichment of phosphopeptides.

Highly selective and efficient enrichment of trace phosphorylated proteins or peptides from complex biological samples is of profound significance for the discovery of disease biomarkers in biological systems. In this study, a novel immobilized metal affinity chromatography (IMAC) material has been synthesized to improve the enrichment specificity and sensitivity for phosphopeptides by introducing a titanium phosphate moiety on a multilayer polysaccharide (hyaluronate (HA) and chitosan (CS)) coated Fe3O4@SiO2 nanoparticle (denoted as Fe3O4@SiO2@(HA/CS)10-Ti4+ IMAC). The thicker multilayer polysaccharide endows excellent hydrophilic properties and a higher binding capacity of the titanium ion to the IMAC material. Due to the combination of uniform magnetic properties, highly hydrophilic properties and enhanced binding capacity of the titanium ion, the Fe3O4@SiO2@(HA/CS)10-Ti4+ nanoparticle possesses many merits, such as high selectivity for phosphopeptides (phosphopeptides/non-phosphopeptides at a molar ratio of 1 : 2000), extreme detection sensitivity (0.5 fmol), large binding capacity (100 mg g-1), high enrichment recovery (85.45%) and rapid magnetic separation (within 10 s). Moreover, the as-prepared IMAC nanoparticle provides effective enrichment of phosphopeptides from real samples (human serum and nonfat milk), showing great potential as a tool for the detection and identification of low-abundance phosphopeptides in biological samples.

Ectopic, autologous eutopic and normal endometrial stromal cells have altered expression and chemotactic activity of RANTES.

OBJECTIVE: To evaluate if the expression and chemotactic activity of RANTES are different in IL-1beta treated autologous eutopic endometrial stromal cells compared to ectopic and normal endometrium. STUDY DESIGN: Conditioned media from IL-1beta-treated ectopic, autologous eutopic and normal endometrial stromal cells were analyzed with a specific sandwich ELISA to quantify RANTES. The monocyte chemotactic activity of RANTES was assayed in a Boyden Chamber. RESULTS: RANTES expression in IL-1beta-treated autologous eutopic and normal endometrial stromal cells was significantly lower than ectopic endometrium. Autologous eutopic endometrial stromal cells showed a significant increase in RANTES expression compared to normal endometrium after IL-1beta stimulation for 60 h. The monocyte chemotactic activities of these conditioned media were highly correlated with the immunoreactive RANTES concentration. We observed significantly increased monocyte chemotactic activity in conditioned media of ectopic stromal cells compared to autologous eutopic and normal endometrium. The different chemotactic activity of RANTES between the autologous eutopic and normal endometrial stromal cells was also statistically significant. RANTES accounts for the majority (62%) of the monocyte chemotactic activity in ectopic endometrial stromal cells conditioned media and 55% of that activity in autologous eutopic endometrium. CONCLUSIONS: Although the eutopic endometric of women with and without endometriosis are histologically similar, our findings confirm that different expression and chemotactic activity of RANTES exist between autologous eutopic and normal endometrium. The altered expression of RANTES and monocyte chemotactic activity observed in ectopic, autologous eutopic and normal endometrium suggest the autologous eutopic endometrium may contribute to the pathogenesis of endometriosis.

[Influence of nuclear factor-kappaB decoy oligonucleotides on RANTES expression and monocyte chemotactic activity in stromal cells of ectopic endometrium].

OBJECTIVE: To study the inhibitory effect on the expression of regulated upon activation, normal T cell expressed and secreted (RANTES) and monocyte chemotactic activity of ectopic endometrial stromal cells by nuclear factor (NF)-kappaB decoy oligonucleotides (ODN). METHODS: The stromal cells of ectopic endometrium were divided into 3 groups. Two groups were cultured with or without 10 microg/L of interleukin (IL)-1beta. Another group was transfected with NF-kappaB decoy ODN with the aid of a lipofectamine reagent. After 4 h of transfection, 10 microg/L of IL-1beta was added to induce the stromal cells to secrete RANTES. Concentration of RANTES in the supernatant at 4, 8, 12, 24 and 36 h was measured with the sandwich enzyme linked immunosorbent assay (ELISA). U937 monocyte chemotactic activity was assayed in Boyden chambers. The specific RANTES-neutralizing monoclonal antibodies at serial doses (0.5, 1, 2, 4 and 8 mg/L) were added into IL-1beta induced medium of 24 h to detect the monocyte chemotactic activity of RANTES in supernatant. RESULTS: The concentration of RANTES secreted by stromal cells was respectively (58 +/- 10), (150 +/- 35), (360 +/- 46) and (586 +/- 42) ng/L after IL-1beta stimulation for 8, 12, 24 and 36 h, significantly higher than that of stromal cells cultured without IL-1beta. The concentrations of RANTES were respectively (86 +/- 16), (128 +/- 28) and (183 +/- 32) ng/L after IL-1beta stimulation for 12, 24 and 36 h in stromal cells transfected with NF-kappaB decoy ODN, evidently lower than that of stromal cells stimulated with IL-1beta alone. The monocyte chemotactic index of 12, 24, 36 h in conditioned medium of stromal cells transfected with NF-kappaB decoy ODN was respectively 10.3 +/- 0.9, 13.7 +/- 1.1, 18.6 +/- 1.2, which was evidently lower than that of stromal cells stimulated with IL-1beta alone. The anti-RANTES antibody at 0.5, 1, 2, 4 and 8 mg/L inhibited respectively 5%, 23%, 40%, 62% and 61% of the chemotactic activity in 12 h medium treated with IL-1beta. CONCLUSIONS: RANTES accounts for the majority of the monocyte chemotactic activity in IL-1beta induced medium of 24 h. NF-kappaB decoy ODN may influence the feed-forward inflammatory loop whereby IL-1beta from activated macrophages can lead to RANTES production by ectopic implants and further monocyte chemotaxis.