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Niosomes composed of Tween 61 and cholesterol at 1:1 molar ratio were entrapped with the mixture of the three semi-purified rice (Oryza sativa L., Family Gramineae) bran bioactive compounds [ferulic acid (F), γ-oryzanol (O), and phytic acid (P)] at 0.5%, 1.5%, and 1.5%, respectively, by the supercritical CO2 technique. The transdermal absorption by vertical Franz diffusion cells of the compounds entrapped in niosomes (Nio FOP), the unentrapped compounds (Mixed FOP), the compounds incorporated in gel and cream (Gel FOP and Cream FOP), and the compounds entrapped in niosomes and incorporated in gel and cream (Gel nio and Cream nio) was investigated. At 6 h, F and P from Nio FOP gave lower cumulative amount in viable epidermis and dermis (VED) than from Mixed FOP of 1.1 and 1.6 times, respectively, while O from Nio FOP exhibited higher cumulative amount in VED than from Mixed FOP of 2.4 times. The highest cumulative amount in VED of F, O, and P were from Gel nio, Cream nio, and Mixed FOP at 1.564 ± 0.052, 15.972 ± 0.273, and 25.857 ± 0.025 ng/cm2, respectively. Niosomes enhanced the transdermal absorption of the hydrophobic compound O, while retarded the hydrophilic compounds F and P indicating the less systemic risk of F and P than O when entrapped in niosomes. Thus, transdermal absorption of F, O, and P appeared to depend on niosomal size, lipophilicity of the bioactive compounds, and types of formulations. These preclinical results can be applied for the design of the clinical study of the developed rice bran niosomal topical products.  相似文献   
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An enhancement of 17α-hydroxyprogesterone (17α-HP) production from progesterone by biotransformation using hydroxypropyl-β-cyclodextrin (HPβCD) complexation together with aeration and sonication technique was demonstrated. The progesterone–hydroxypropyl-β-cyclodextrin complex was prepared by co-evaporation method. The percentage yield of 17α-HP from P of 11.26 ± 0.64% at 24 h was observed in Curvularia lunata ATCC 12017. In the complex form of P, together with sonication at 40 kHz for 5 s and aeration, the yield of 17α-HP was increased to 72.92 ± 4.28% which was about 6.5 and 1.3 times of that from the uncomplexed (P) and the complexed (PC), respectively without sonication and aeration. The increased aqueous solubility of P by complexation with HPβCD was the main factor which increased the yield of 17α-HP, while aeration had more effect on P than PC. Sonication did not significantly increased the yield of the product from both P and PC. When both aeration and sonication were used in the PC system, the product yield was increased significantly more than that from P. The result from this study can be applied for the biotransformation of other poor aqueous soluble precursors.  相似文献   
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Transdermal absorption of luciferase plasmid (pLuc) was enhanced by loading in elastic cationic liposomes and niosomes and the application of iontophoresis or the stratum corneum (SC) stripping method. Cationic liposomes (DPPC/Chol/DDAB at a 1:1:1 molar ratio) and niosomes (Tween61/Chol/DDAB at a 1:1:0.5 molar ratio) were prepared by the freeze-dried empty liposomes method. The elastic vesicles were prepared by hydrating the lipid or surfactant film by 25% of ethanol instead of distilled water. Gel electrophoresis of all nanovesicles showed the 100% pLuc entrapment efficiency. All nanovesicles loaded with pLuc showed larger vesicular sizes than the nonloaded vesicles of about 1.4 times for liposomes and 1.7 times for niosomes. The nanovesicles loaded with pLuc demonstrated less positive zeta potential than the nonloaded vesicles. The pLuc loaded in elastic vesicles kept at 4 ± 2 and 27 ± 2°C for 8 weeks gave the remaining pLuc of about 70 and 60% for liposomes and 85 and 73% for niosomes, respectively. For nonelastic vesicles kept at 4 ± 2°C, 56 and 61% of the remaining pLuc were observed for liposomes and niosomes, respectively, while at 27 ± 2°C, all pLuc were degraded. The deformability indices of the elastic liposomes and niosomes loaded with the pLuc were 16.64 ± 2.92 and 20.72 ± 0.82, whereas the nonelastic vesicles gave 9.35 ± 0.09 and 10.08 ± 0.12, respectively. Transdermal absorption through rat skin pretreated with SC stripping or treated with iontophoresis of pLuc loaded in nanovesicles by vertical Franz diffusion cells was investigated at 37°C. The cells were stopped and the skin and the receiving solution were withdrawn at 1, 3, and 6 hours and the pLuc contents in the stripped SC, whole skin (viable epidermis and dermis; VED), and the receiving solution were assayed by the modified gel electrophoresis and gel documentation. Without the SC stripping technique or iontophoresis, the pLuc loaded and nonloaded in nonelastic cationic liposomes or niosomes were not found in SC, VED, and receiving solution. The fluxes in the whole skin of pLuc loaded in nonelastic liposomes and niosomes with SC stripping and iontophoresis at 6 hours gave 2.73 ± 0.46 and 3.83 ± 0.73, and 7.01 ± 1.22 and 9.60 ± 1.31 g/cm2/h, respectively, while pLuc loaded in elastic liposomes and niosomes without the SC stripping and iontophoresis at 6 hours showed 2.79 ± 0.09 and 2.84 ± 0.04 g/cm2/h, respectively. The pLuc loaded in elastic niosomes or in nonelastic niosomes with iontophoresis was found in the receiving solution with a higher amount than that loaded in elastic liposomes or nonelastic liposomes with iontophoresis. The fluxes in the receiving solution of pLuc loaded in nonelastic liposomes and niosomes with iontophoresis at 6 hours were 6.71 ± 0.31 and 8.82 ± 0.28 g/cm2/h, respectively. For elastic liposomes and niosomes, the fluxes of the loaded pLuc in the receiving solution were the same, at about 1.9 g/cm2/h. Although pLuc loaded in nonelastic niosomes with iontophoresis gave the highest delivery of the plasmid in VED and receiving solution, a more promising applicable approach for gene delivery has been suggested to be the elastic niosomal systems, since no equipment is required.  相似文献   
5.
The aqueous extract of Peltophorum pterocarpum (Fabaceae) wood exhibited potent inhibitory effects against Epstein? Barr virus early antigen (EBV‐EA) activation induced with 12‐O‐tetradecanoylphorbol‐13‐acetate (TPA) in Raji cells and against melanogenesis in α‐melanocyte‐stimulating hormone (α‐MSH)‐stimulated B16 melanoma cells, as well as potent 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) free radical‐scavenging activity. Two phenolic acid derivatives, bergenin ( 1 ) and gallic acid ( 2 ), were isolated from the ethyl acetate (AcOEt)‐soluble fraction obtained from the extract. Compound 1 exhibited potent inhibitory effect against EBV‐EA activation and against skin tumor promotion in an in vivo two‐stage mouse skin carcinogenesis test based on 7,12‐dimethylbenz[a]anthracene (DMBA) as initiator, and with TPA as promoter. Both compounds 1 and 2 exhibited melanogenesis‐inhibitory activities in α‐MSH‐stimulated B16 melanoma cells, and, in addition, compound 2 showed strong DPPH radical‐scavenging activity.  相似文献   
6.
A new phloroglucinol derivative, 5‐deprenyllupulonol C ( 1 ), along with four other phloroglucinol derivatives, 2 – 5 , five chalcones, 6 – 10 , four flavanones, 11 – 14 , two flavonol glycosides, 15 and 16 , and five triterpenoids, 17 – 21 , were isolated from the female inflorescence pellet extracts of hop (Humulus lupulus L.). Upon evaluation of these compounds against the Epstein? Barr virus early antigen (EBV‐EA) activation induced by 12‐O‐tetradecanoylphorbol 13‐acetate (TPA) in Raji cells, twelve compounds, i.e., 1 – 4, 11 – 14, 17 – 19 , and 21 , showed potent inhibitory effects on EBV‐EA induction, with IC50 values in the range of 215–393 mol ratio/32 pmol TPA. In addition, eleven compounds, i.e., 1 – 4, 6, 11, 12, 14, 17, 18 , and 20 , were found to inhibit TPA‐induced inflammation (1 μg/ear) in mice, with ID50 values in the range of 0.13–1.06 μmol per ear. Further, lupulone C ( 2 ) and 6‐prenylnaringenin ( 14 ) exhibited inhibitory effects on skin‐tumor promotion in an in vivo two‐stage mouse‐skin carcinogenesis test based on 7,12‐dimethylbenz[a]anthracene (DMBA) as initiator and with TPA as promoter.  相似文献   
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The capacity of 22 molds for 11β-hydroxylation of cortexolone (Reichstein’s compound S) to hydrocortisone were assessed. The biotransformation capacity was compared for solid-state and submerged monocultures of molds that were otherwise under identical conditions. Thin-layer chromatography and a novel rapid color-development assay were used to qualitatively establish the ability of fungi to convert cortexolone to hydrocortisone. These assays were validated and supplemented with data from high-performance liquid chromatography to obtain quantitative information on biotransformation. Nearly all the fungi consumed a significant fraction of the cortexolone fed, but only four of them (i.e., two isolates of Cunninghamella blakesleeana, C. echinulata, and Curvularia lunata) yielded measurable quantities of hydrocortisone. Submerged cultures generally gave a significantly greater yield of hydrocortisone compared to equivalent solid-state cultures. The text was submitted by the authors in English.  相似文献   
9.
Seven phenolic compounds, 1 – 7 , including a new organic acid gallate, mucic acid 1‐ethyl 6‐methyl ester 2‐O‐gallate ( 7 ), were isolated from the MeOH extract of the fruits of Phyllanthus emblica L. (Euphorbiaceae). The structures were elucidated on the basis of extensive spectroscopic analysis and comparison with literature data. Upon evaluated for their antioxidant abilities by 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), 2,2′‐azinobis(3‐ethylbenzthiazoline‐6‐sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays. The inhibitory activities against melanogenesis in B16 melanoma cells induced by α‐MSH, as well as cytotoxic activities against four human cancer cell lines were also evaluated. All phenolic compounds, 1 – 7 , exhibited potent antioxidant abilities (DPPH: IC50 5.6 – 12.9 μm ; ABTS: 0.87 – 8.43 μm Trolox/μm ; FRAP: 1.01 – 5.79 μm Fe2+/μm , respectively). Besides, 5 – 7 , also exhibited moderate inhibitory activities against melanogenesis (80.7 – 86.8% melanin content), even with no or low toxicity to the cells (93.5 – 101.6% cell viability) at a high concentration of 100 μm . Compounds 1 – 3 exhibited cytotoxic activity against one or more cell lines (IC50 13.9 – 68.4%), and compound 1 with high tumor selectivity for A549 (SI 3.2).  相似文献   
10.
The luciferase gene expression of lipoplexes, a liposome containing luciferase plasmid (pCMVLuc), in HeLa cell lines, was investigated. Cationic liposomes were prepared by the chloroform film method with sonication. The lipoplex was formed by loading the liposome with pCMVLuc. The lipoplex with an optimal weight ratio of dimethyl dioctadecyl ammonium bromide (DDAB)/pCMVLuc protected from DNaseI was determined by an agarose gel electrophoresis. The selected lipoplexes were assayed for luciferaase activity by using a luminometer. The effect on cell proliferation was evaluated by WST-1 assay. The highest luciferase activity of 1.5 × 106 RLU was observed in the cholesterol (Chol)/DDAB (2:1 molar ratio) lipoplex at the DDAB/pCMVLuc weight ratio of 10:1 at 48 hours, which was about 10, 100, and 1,000 times higher than the DDAB, L-alpha-dipalmitoyl phosphatidylcholine (DPPC)/Chol/DDAB (1:2:1 molar ratio), and DPPC/Chol/DDAB (2:2:1 molar ratio) lipoplexes, respectively. The liposome with the smallest particle size was obtained from the cationic liposome composed of DPPC/Chol/DDAB (7:1:1 molar ratio) with the ζ potential of 7.17 ± 0.73. The optimal weight ratio of DDAB/pCMVLuc that protected pCMVLuc from DNaseI digestion was 4:1 in the DDAB formulation. The Chol/DDAB (2:1 molar ratio) lipoplex with the DDAB/pCMVLuc of 10:1 showed the highest luciferase activity of 1.5 × 106 RLU and the highest cytotoxicity as well. DPPC/Chol/DDAB (1:1:1 molar ratio)-lipoplex (DDAB/pCMVLuc = 14:1), which had the amount of DPPC and cholesterol not exceeding 33 and 50% mol, respectively, gave the lower gene expression of about 4 times, but lower cytoxicity of about 14 times, than the Chol/DDAB lipoplex (2:1 molar ratio) and was considered to be the most suitable formulation. The results from this study can be applied as a model for the development of a gene-therapeutic dosage form.  相似文献   
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