the chemical components in the decoctions of chinese herbal medicines are not always the same as those in the crude herbs because of the insolubility or instability of some compounds. in this work, a high-performance liquid chromatography (hplc) coupled with electrospray ionization (esi) tandem mass spectrometry method was developed to explore dynamic variation patterns of aconitum alkaloids in...

Nanoemulsion is an alternative and promising approach to overcome insolubility and bioavailability problems of bioactive compounds. In this study, the sonication parameter for preparing nanoemulsions with high α- tocopherol and linolenic acid content were optimized by using response surface methodology and their stability were evaluated during 2 months’ storage. The response surface analysis re...

Various measures have been proposed for characterizing the statistical association that arises between alleles at different loci. Hedrick has compared these measures with the standardized measure D' proposed by Lewontin on the grounds that this latter measure is independent of allele frequency. Although D' has the same range for all allelic frequencies, in fact, D' is not "independent" of allel...

T7 early mRNA produced by a gene 1 amber mutant phage, T7 am27, is chemically stable interms of acid insolubility and T7 DNA hybridizability. However, the messenger activity of individual T7 early mRNA species, transcripts of gene 1, gene 0.7, and gene 1.3, decay with a half-life of about 6.5 min at 30 C. An extensive secondary structure is present in all T7 early mRNA species and is probably r...

Investigations were started to develop methods for isolating beneficial polyphenols from hops. As a result two new types of extracts were developed. One is mainly consisting of prenylflavonoids (main ingredient is xanthohumol). This product is not soluble in water but in ethanol. The other extract is water soluble and rich in glycosidically bound polyphenols (multifidol, quercetin, kaempferol)....

severe drawbacks, mainly their toxicity and the production of large amount of waste. In addition, sodium periodate is not effective in nonpolar solvents due to its insolubility, and it is also able to oxidize other functional groups such as alcohols, alkenes, aromatics, sulphides,.. whereas its reactions with ditertiary 25 glycols do not proceed. Several other oxidizing systems have been develo...

Iron is essential to life, but poses severe problems because of its toxicity and the insolubility of hydrated ferric ions at neutral pH. In animals, a family of proteins called transferrins are responsible for the sequestration, transport, and distribution of free iron. Comparison of the structure and function of transferrins with a completely unrelated protein hemopexin, which carries out the ...

Two mucopolysaccharides, chondroitin 4-sulfate (97.8%) and hyaluronic acid (1.2%), were isolated after exhaustive proteolysis of a transplantable chondrosarcoma of the rat. The chondroitin 4-sulfate was fractionated into three fractions of varying degrees of sulfation and chain length. Keratan sulfate and chondroitin 6-sulfate were absent. Extraction of the fresh tumor gave two protein-polysacc...