Typical sediments from Taihu Lake, a meso-to-hypereutrophic lake, were collected and examined on the basis of P-fractionation by sequential extraction scheme. Sedimentary inorganic phosphorus were fractioned into four...Typical sediments from Taihu Lake, a meso-to-hypereutrophic lake, were collected and examined on the basis of P-fractionation by sequential extraction scheme. Sedimentary inorganic phosphorus were fractioned into four forms and the rank order according to the mean concentration of P-fractions in Taihu Lake was NaOH-P>BD-P>HCl-P>NH_4Cl-P. The concentrations of BD-P were linearly correlated with the content of active Fe(R2=0.96). Also, the linear relationship between the sum of BD-P and NaOH-P and the sum of active Fe and active Al content was observed within the six sediments investigated(R2=0.96). Moreover, the bio-available phosphorus(BAP) content was estimated by the sum of NH_4Cl-P, BD-P, and NaOH-P, viz. BAP=NH_4Cl-P+NaOH-P+BD-P. In Taihu Lake, the BAP contents are ranging from 0.10 mg/g dw to 1.25 mg/g dw, and average 0.40 mg/g dw for all sediment samples. The relative contributions of BAP to total sedimentary phosphorus(TP) and inorganic sedimentary phosphorus(IP) range from 18.67% to 50.79%(33.61% on average) and from 52.82% to 82.09%(67.81% on average), respectively.展开更多
Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present study.Conditions for the enzymatic reaction were optimized to be 60℃a...Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present study.Conditions for the enzymatic reaction were optimized to be 60℃and pH 7.0,and a desir-able extraction efficiency was achieved by using the crude collagenolytic protease.Dynamic light scattering,transmission electron microscopy and energy-dispersive X-ray analysis revealed that nano-HA are anionic spherical(about 110nm)particles mainly com-prised of calcium and phosphorus at an approximate ratio of 5:3.As evaluated with the mouse ex vivo intestinal segments,the extracted nano-HA displayed comparable level of intestinal bioavailability to the positive control CaCl_(2).By treating with inhibitors(NaN3,ami-loride)and low temperature(4℃),clathrin-mediated endocytosis was assumed to involve the intestinal absorption of nano-HA.Over-all,the application of thermostable collagenolytic protease is proved to be a promising alternative method for nano-HA extraction from natural resource with improved ecological and biological value.展开更多
The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-c...The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-cyclodextrin(Am80-HP-β-CD)was prepared through a freeze-drying method at the mole ratio of 1:1(Am80:HP-β-CD).Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry(DSC)indicated the formation of Am80-HP-β-CD.In vitro dissolution studies showed that the solubility and dissolution percentage of Am80-HP-β-CD was improved substantially compared to Am80.An improved dissolution with approximately 97%drug release in 3 min was observed,in comparison with Am80 with approximately 60% release in 45 min.In vivo studies indicated that the AUC0-∞ has increased 2.79 times and the Cmax 4.37 times after the formation of inclusion complex.The decrease of tmaxindicated the Am80-HP-β-CD inclusion complex can be absorbed into blood faster.In short,the solubility and bio-availability of Am80 has notably increased with the complexation of HP-β-CD.Therefore,using the inclusion technique is a promising method to improve the solubility of insoluble drugs.展开更多
基金The Grand Projects of Innovation Engineering Chinese Academy of Sciences(No. KZCX1 SW 12 2002 2006)
文摘Typical sediments from Taihu Lake, a meso-to-hypereutrophic lake, were collected and examined on the basis of P-fractionation by sequential extraction scheme. Sedimentary inorganic phosphorus were fractioned into four forms and the rank order according to the mean concentration of P-fractions in Taihu Lake was NaOH-P>BD-P>HCl-P>NH_4Cl-P. The concentrations of BD-P were linearly correlated with the content of active Fe(R2=0.96). Also, the linear relationship between the sum of BD-P and NaOH-P and the sum of active Fe and active Al content was observed within the six sediments investigated(R2=0.96). Moreover, the bio-available phosphorus(BAP) content was estimated by the sum of NH_4Cl-P, BD-P, and NaOH-P, viz. BAP=NH_4Cl-P+NaOH-P+BD-P. In Taihu Lake, the BAP contents are ranging from 0.10 mg/g dw to 1.25 mg/g dw, and average 0.40 mg/g dw for all sediment samples. The relative contributions of BAP to total sedimentary phosphorus(TP) and inorganic sedimentary phosphorus(IP) range from 18.67% to 50.79%(33.61% on average) and from 52.82% to 82.09%(67.81% on average), respectively.
基金supported by the Natural Science Foundation of Shandong Province(No.ZR202102270334)the National Key Research and Development Program of China(No.2020YFD0901004).
文摘Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present study.Conditions for the enzymatic reaction were optimized to be 60℃and pH 7.0,and a desir-able extraction efficiency was achieved by using the crude collagenolytic protease.Dynamic light scattering,transmission electron microscopy and energy-dispersive X-ray analysis revealed that nano-HA are anionic spherical(about 110nm)particles mainly com-prised of calcium and phosphorus at an approximate ratio of 5:3.As evaluated with the mouse ex vivo intestinal segments,the extracted nano-HA displayed comparable level of intestinal bioavailability to the positive control CaCl_(2).By treating with inhibitors(NaN3,ami-loride)and low temperature(4℃),clathrin-mediated endocytosis was assumed to involve the intestinal absorption of nano-HA.Over-all,the application of thermostable collagenolytic protease is proved to be a promising alternative method for nano-HA extraction from natural resource with improved ecological and biological value.
文摘The goal of this study was to improve the solubility and oral bioavailability of tamibarotene by complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD).The inclusion complex of tamibarotene with hydroxypropyl-β-cyclodextrin(Am80-HP-β-CD)was prepared through a freeze-drying method at the mole ratio of 1:1(Am80:HP-β-CD).Fourier transform infrared spectroscopy(FT-IR)and differential scanning calorimetry(DSC)indicated the formation of Am80-HP-β-CD.In vitro dissolution studies showed that the solubility and dissolution percentage of Am80-HP-β-CD was improved substantially compared to Am80.An improved dissolution with approximately 97%drug release in 3 min was observed,in comparison with Am80 with approximately 60% release in 45 min.In vivo studies indicated that the AUC0-∞ has increased 2.79 times and the Cmax 4.37 times after the formation of inclusion complex.The decrease of tmaxindicated the Am80-HP-β-CD inclusion complex can be absorbed into blood faster.In short,the solubility and bio-availability of Am80 has notably increased with the complexation of HP-β-CD.Therefore,using the inclusion technique is a promising method to improve the solubility of insoluble drugs.