Fabrication and characterization of the nano-composite of whey protein hydrolysate chelated with calcium.

The nano-composites of whey protein hydrolysate (WPH) chelated with calcium were fabricated in aqueous solution at 30 °C for 20 min, with the ratio of hydrolysate to calcium 15 : 1 (w/w). UV scanning spectroscopy, fluorescent spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering and atomic force microscopy were applied to characterize the structure of the WPH-calcium chelate. The nano-composites showed the successful incorporation of calcium into the WPH, indicating the interaction between calcium and WPH. The chelation of calcium ions to WPH caused molecular folding and aggregation which led to the formation of a WPH-calcium chelate of nanoparticle size, and the principal sites of calcium-binding corresponded to the carboxyl groups and carbonyl groups of WPH. The WPH-calcium chelate demonstrated excellent stability and absorbability under both acidic and basic conditions, which was beneficial for calcium absorption in the gastrointestinal tract of the human body. Moreover, the calcium absorption of the WPH-calcium chelate on Caco-2 cells was significantly higher than those of calcium gluconate and CaCl2 in vitro, suggesting the possible increase in calcium bioavailability. The findings suggest that the WPH-calcium chelate has the potential in making dietary supplements for improving bone health of the human body.

Increase in the free radical scavenging capability of bitter gourd by a heat-drying process.

Bitter gourd (Momordica charantia Linn.) is widely regarded as one of the best remedy foods for diabetes. The positive effect of bitter gourd on diabetes has been attributed in part to the remarkable free radical scavenging activity of its boiled water extract from sun-dried fruits. It is well known that a heat process significantly influences the antioxidant activity of fresh fruits. However, the heat drying processes of bitter gourd have not been studied so far. Here, we show that the free radical scavenging capability of bitter gourd extract significantly increases after the heat drying process, while the content of flavonoids and phenols, which are generally regarded as the main antioxidant components in bitter gourd, remain unaffected. Furthermore, the content of free amino acids and the total reducing sugar were found to decrease with increasing browning index, indicating the progression of the Maillard reaction, products of which are known to possess significant antioxidant activity. Therefore, it suggests that Maillard reaction products may be the main contributors to the increase in antioxidant capability. Finally, the bitter gourd extract with the higher antioxidant activity, was shown to manifest a corresponding higher proliferation activity on NIT-1 beta-cells. These results suggest that controllable conditions in the heat-drying processing of fresh bitter gourd fruit is of significance for enhancing the total free radical scavenging capacity, beta-cell proliferation activity and possibly the anti-diabetic activity of this fruit.

PTD mediated protein transduction technology and its application in medical field / 生物医学工程学杂志

The delivery of bioactive macromolecular substances into cells provides an efficient approach to changing cellular conditions, and is thus of enormously potential therapeutic significance. It has also been an extremely difficult approach due the the impediment and protective nature of cell membrance until the protein transduction domain's (PTD's) capability to ferry macromolecule across cell membrance was discovered. PTD's efficient transductive function has rendered an exciting promise to the clinical treatment of diseases, therapeutic proteins drug development, and basic medical and applied research. The technology has been successfully applied to deliver a variety of substances into cells or tissue organs, and its superior application values have been explicitly demonstrated.

In vivo and in vitro effect of peptide HP-6 derived from donkey serum albumin on hematopoietic system / 中国中药杂志

<p><b>OBJECTIVE</b>By bioinformatics method, the effect in hematopoietic system of bioactive peptide HP-6, which was obtained from donkey serum albumin and is one of the major protein components from donkey-hide gelatin, was investigated.</p><p><b>METHOD</b>Human bone marrow nucleated cells (hBMNCs) and murine bone marrow stromal cells (mBMSCs) were separated and cultured with different concentration of peptide HP-6 (0.000 15, 0.001 5, 0.015, 0.15, 1.5 micromol x L(-1)). The effect on promoting proliferation of cells related to hematopoiesis in bone morrow was detected and the ultrastructure of cells after treated by HP-6 was observed through transmission electron microscope. Hemorrhage anemia mouse model and anemia mouse model induced by cyclophosphamide were established, and randomly divided into peptide HP-6 groups which were administered respectively with different doses (1, 0.1, 0.01 mg x kg(-1)) by gavage, and control group which was administered with PBS by gavage. Peripheral blood components of all mice and bone morrow cells (BMC) number of mice induced by cyclophosphamide were evaluated.</p><p><b>RESULT</b>Peptide HP-6 could concentration-related promote the proliferation of hBMNCs and mBMSCs, hBMNCs got the highest reproduction rate of 152.11% and mBMSCs also got 63.52% with the concentration of 0.15 micromol x L(-1), then the reproduction rate decreased while the concentration kept increasing. The transmission electron microscope showed that ultrastructure of cells was normal after treated by HP-6.1 mg x kg(-1) peptide HP-6 significantly increased peripheral platelet and protected mouse morrow injured by cyclophoshamide. 0.1 mg x kg(-1) peptide HP-6 significantly increased peripheral platelet with relative growth rate of 77.65%, increased peripheral white blood cells count and peripheral red blood cells count, also could protect mouse peripheral blood after treated by chemotherapeutics.</p><p><b>CONCLUSION</b>Peptide HP-6 could promote the proliferation of cells related to hematopoietic system, enhance mouse hemopoiesis function and the resistance to chemotherapeutic injury.</p>

Efficacy of topical application of PTD-SOD on wound healing in mice with mechanical injury / 中华创伤杂志

Objective To study the role of the oxidative stress in the development of wound healing and observe the effect of the antioxidant PTD-SOD on damage and inflammation reaction after mechanical wound. Methods In this experiment,acute wound healing model by removal the whole layer dorsal skin of the mice was prepared,SOD(3 000 U and 6 000 U)and the fusion protein PTD-SOD with different concentrations(1 000 U,3 000 U,6 000 U and 10 000 U)were used to deal with the wounds continuously for 13 days.The mice were divided into different concentration SOD treatment group and PTD-SOD treatment group,model control group,physiological saline treatment group and compound iodine solution control group.The wound healing situation and healing percentage of the fight and left skin wounds of each mouse in every group was recorded every day.At day 14 after wound,the wound healing skin of each group was removed and some were used to make 10%tissues homogenate for detecting the activities of superoxide dismutase(SOD),catalase(CAT),glutathione peroxidase(GSH-Px)and contents of malondialdehyde(MDA)and hydroxyproline(Hyp);in the meantime,the other removed skin were fixed in 10% formalin for observing the histopathological changes of the tissues. Results Compared with the model control group,the physiological saline treatment group and the compound iodine solution control group,the skin wound healing percentage was significantly(P<0.05 or P<0.01)improved,with increase of the activities of SOD,CAT,GSH-Px and contents of Hyp (P<0.05 or P<0.01)and decrease of MDA(P<0.05 or P<0.01) in the SOD groups or PTD-SOD groups (except for 10 000 U PTD-SOD group).When compared with the physiological saline treatment group or the compound iodine solution treatment group,the effect was similar to the model control group.In comparison to the SOD groups,under the same dosage and environment condition,the PTD-SOD groups were much better than SOD groups with regard to promoting skin wound healing percentage,increasing activities of antioxidases and contents of Hyp,decreasing contents of MDA.Among the PTD-SOD groups,the effect of high dosage 10 000 U on promoting skin wound healing was declined. Conclusions The oxidative stress may playan important role in the development of wound healing.Proper application of treatment with antioxidants is a alternative strategy in the early stage of wound.PTD-SOD is able to prevent the oxidative stress damage,inhibit inflammatory infiltration and promote skin wound healing efficiently.

Expression in Escherichia coli, purification and enzymatic properties of chicken aminopeptidase H / 生物工程学报

Aminopeptidase H (APH) is an universally distributed aminoendopeptidase in the tissue of many organism. However, it is hard to investigate its mechanism underlying the catalysis and the function in cell. In this paper, the full DNA sequence of this enzyme was cloned from chicken liver, then subcloned to the vector pET22 b(+). The recombined vector was transformed into E. coli Rosetta(DE3), and the APH gene was expressed by the induction of IPTG. It was found the recombinant protein exhibited same mo lecular weight as authentic APH on SDS-PAGE analysis; the expression level increased with induction time and approached maximum of 94.7 mg/L till 6 hours, which contained 16.7% of the total protein. Moreover, this recombinant protein showed similar prop erties of subunit composition, thermal stability and optimum pH with native APH, based on the enzymatic assay, purification and analysis of enzymological properties. Therefore, it is confirmed that APH was expressed in this prokaryote system with a high-level of 1636 u/L aminopeptidase activity. These results would help to elucidate the catalysis mechanism and biological function of APH by providing enough material.

Application of egg-yolk-antibody to prevent recolonization of Streptococcus mutans / 实用口腔医学杂志

Objective:To investigate the effect of local application of the water soluble protein fraction,containing specific egg yolk antibody,on the recolonization of Streptococcus mutans.Methods:Whole cells of inactivated streptococcus mutans were used as antigen to immunize bens,then water soluble protein fraction(WSF) was extracted from the eggs. Mouth wash containing 0.1 mg/ml of WSF was prepared and administered to 8 volunteers.The mouth wash was used once every two days for 2 weeks.Vehicle solution was used in other 6 volunteers as the control.S.mutans in saliva was monitored for 100 days.Results:Before using the mouth washes,S.mutans level in saliva of the volunteers was 36.4%.S.mutans was removed by hibitane,it kept less than 3% in 100 days in the tested individuals,while 23%～37% in the controls.Conclusion:The WSF containing specific egg yolk antibody can effectively prevent the recolonization of streptococcus mutans.

Isolation and PC12 cell proliferative protein fraction from pilose antler and its activity / 中草药

Objective The lyophilized pilose antler water extract(PAE) was isolated,and their cell proliferation on PC12 cells was observed.Methods S-200 Size-exclusive gel and DEAE negative ion-exchange liquid chromatograph were employed to fractionate the PAE.SDS-PAGE was employed to analyze the proteins composition of PAE.The protein concentration was determined by Folin-Phenol assay.The proliferation rates of PC12 cells were measured by MTT assay.Results The proliferation rate of PAE on PC12 cells at 13.3 mg/mL was 47%(P