Diosgennin has been analyzed by gas chromatography with glass column that was silanated at high temperature. The method has got less than 3 per-cents of error. This method was introduced in practical production of pharmaceutical industry.
Chromatography, Gas ; Diosgenin ; Pharmaceutical Preparations

As a naturally occurring steroid sapogenin, diosgenin acts as the precursor of hundreds of steroid medicines, and thereby has important medicinal value. Currently, industrial production of diosgenin relies primarily on chemical extraction from plant materials. Clearly, this strategy shows drawbacks of excessive reliance on plant materials and farmland as well as environment pollution. Due to development of metabolic engineering and synthetic biology, bio-production of diosgenin has garnered plenty of attention. Although the biosynthetic pathways of diosgenin have not been completely identified, in this review, we outline the identified biosynthetic pathways and key enzymes. In particular, we suggest heterologous biosynthesis of diosgenin in Saccharomyces cerevisiae. Overall, this review aims to provide valuable insights for future complete biosynthesis of diosgenin.
Biosynthetic Pathways/genetics* ; Diosgenin ; Metabolic Engineering

Steroidal saponins, important natural organic compounds in Paris polyphylla var. yunnanensis, have good biological activity. Structural modification of steroidal saponins by microbial transformation could produce a large number of products with novel structures and excellent bioactivity, which can provide functional compounds for the research and development of steroidal drugs. This study summarized the research progress in steroidal saponins and their microbial transformation in P. polyphylla var. yunnanensis. P. polyphylla var. yunnanensis contains 112 steroidal saponins, 8 of which are used as substrates in 35 transformation reactions by 25 microbial species, with the highest transformation rate of 95%. Diosgenin is the most frequently used substrate. Furthermore, the strains, culture medium, reaction conditions, transformation rate, transformation reaction characteristics, and biological activities of the transformed products were summarized. This review may provide reference for the further research on microbial transformation of steroidal saponins in P. polyphylla var. yunnanensis.
Diosgenin/analysis* ; Liliaceae/chemistry* ; Melanthiaceae/chemistry* ; Rhizome/chemistry* ; Saponins/analysis*

Diosgenin is widely distributed in many plants, such as Polygonatum sibiricum, Paris polyphylla, Dioscorea oppositifolia, Trigonella foenum-graecum, Costus speciosus, Tacca chantrieri, which has good anti-tumor activity and preferable effects on preventing atherosclerosis, protecting the heart, treating diabetes, etc. This review combed through the anti-tumor mechanisms of diosgenin encompassing lung, breast, gallbladder, liver, oral cavity, stomach, bladder, bone marrow, etc. Besides, it was discovered that diosgenin mainly exerts its effect by inhibiting tumor cell migration, suppressing tumor cell proliferation and growth, and inducing cell apoptosis. However, problems like low yield and bioavailability frequently exist in natural diosgenin. This review introduced methods such as structural modification, dosage form optimization and combination medication to improve the yield and anti-tumor activity of diosgenin. Via the summary of this paper, it is expected to provide theoretical basis for the rational exploitation and utilization of diosgenin.
Apoptosis ; Biological Products ; Cell Proliferation ; Diosgenin/pharmacology* ; Trigonella

Diosgenin is an important raw material in steroid hormone and widely used in pharmaceutical industry. The traditional method for diosgenin production is acidolysis, which causes serious pollution. In order to obtain a cleaner and more efficient approach of diosgenin production, a strain of Gibberella intermedia WX12 (the sexual stage of Fusarium proliferatum) was screened from the strains deposited in our laboratory. This strain converted saponins in Dioscorea zingiberensis C.H. Wright (DZW) into diosgenin. The conversion medium was optimized by statistical experimental design. The optimized conversion medium was as follows (g/L): glucose 20.6, yeast extract 5.0, NaCl 1, K2PO4 3, ZnSO4 x 7H2O 1.5 and saponins 3. Under the optimal conditions, the yield of diosgenin achieved to (31 +/- 0.3) mg/g DZW, which was 3 times higher than that of the original medium.
Biotransformation ; Culture Media ; Dioscorea ; chemistry ; Diosgenin ; metabolism ; Gibberella ; growth & development ; metabolism ; Saponins ; metabolism

To breed a new yam cultivar of Dioscorea alata, the different and excellent germplasm resources were investigated within artificially cultivated population and some superior individuals, with a higher yield and medicinal properties, were selected. Considering results of the yield and medicinal properties during 2006-2013 cropping season, strains and lines were established and selected. As a result, the yield of the new developed cultivar (Wenshanyao No. 1, WSY01-1) reached 2217. 0 kg per 667 m2 (fresh weight) and 348.3 kg per 667 m2 (dry weight), and increased 23.8% and 23.9% comparing with control cultivars (landraces). Comparing with control cultivars, the level of polysaccharide, allantoin, and dioscin increased 36.9%, 48.3%, 20.9%, and reached 12.2%, 1.30%, 579.7 µg · g(-1), respectively. This result showed that the systematic selection method can significantly improve yield and medicinal properties of D. alata, and the developed " Wenshanyao No. 1" exhibits wide spreading prospects.
Allantoin ; analysis ; Breeding ; Dioscorea ; chemistry ; genetics ; growth & development ; Diosgenin ; analogs & derivatives ; analysis ; Polysaccharides ; analysis

OBJECTIVETo study the production technology of extraction in combination hydrolysis in situ for isolating diosgenin from Dioscorea nipponica by orthogonal design.

METHODThe optimum production conditions were investigated with the recovery of diosgenin as an index by extraction in combination hydrolysis in situ, and were compared with the traditional method.

RESULTExtraction in combination hydrolysis in situ conducted in 1.5 mol x L(-1) sulfuric acid of water containing 75% isopropanol at 100 degrees C for 4.5 h could get higher recovery of diosgenin than traditional methods.

CONCLUSIONThis production technology can get higher recovery of diosgenin, and it is simple, time and money saving.

Dioscorea ; chemistry ; Diosgenin ; isolation & purification ; Hydrolysis ; Pressure ; Sulfuric Acids ; Technology, Pharmaceutical ; methods ; Temperature ; Time Factors

OBJECTIVETo develop an HPLC method for the determination of pseudoprodioscin in Dioscorea panthaica and provide scientific basis for quality control of it and its preparation.

METHODThe analysis was carried out on a Merck Purospher STAR RP-18e column eluted with acetonitrile and water as mobile phases in gradient mode. The detection wavelength was 203 nm, and the flow rate was 1.0 mL min(-1).

RESULTThe pseudoprodioscin in D. panthaica extract was well separated. The linear range is between 0.0800-4.00 microg, r =0.9999. The average recovery and RSD are 99.9% and 2.3%, respectively.

CONCLUSIONThis method for quantitation of pseudoprodioscin in D. panthaica is simple, accurate and reliable and can be used for the quality control of D. panthaica and its preparations.

Chromatography, High Pressure Liquid ; methods ; Dioscorea ; chemistry ; Diosgenin ; analogs & derivatives ; analysis ; Drugs, Chinese Herbal ; analysis

In this study, the authors cloned a glycosyltransferase gene PpUGT2 from Paris polyphylla var. yunnanensis with the ORF length of 1 773 bp and encoding 590 amino acids. The phylogenetic tree revealed that PpUGT2 belonged to the UGT80A subfamily and was named as UGT80A49 by the UDP-glycosyltransferase(UGT) Nomenclature Committee. The expression vector pET28a-PpUGT2 was constructed, and enzyme catalytic reaction in vitro was conducted via inducing protein expression and extraction. With UDP-glucose as sugar donor and diosgenin and pennogenin as substrates, the protein was found with the ability to catalyze the C-3 hydroxyl β-glycosylation of diosgenin and pennogenin. To further explore its catalytic characteristic, 15 substrates including steroids and triterpenes were selected and PpUGT2 showed its activity towards the C-17 position of sterol testosterone with UDP-glucose as sugar donor. Homology modelling and molecule docking of PpUGT2 with substrates predicted the key residues interacting with ligands. The re-levant residues of PpUGT2-ligand binding model were scanned to calculate the corresponding mutants, and the optimized mutants were obtained according to the changes in binding affinity of the ligand with protein and the surrounding residues within 5.0 Å of ligands, which had reference value for design of the mutants. This study laid a foundation for further exploring the biosynthetic pathway of polyphyllin as well as the structure of sterol glycosyltransferases.
Ligands ; Glycosyltransferases/genetics* ; Sterols ; Phylogeny ; Ascomycota ; Liliaceae/chemistry* ; Melanthiaceae ; Diosgenin ; Sugars ; Glucose ; Uridine Diphosphate

Polygonatum cyrtonema belongs to the plant family Liliaceae, and its dried rhizome is one of the sources of Chinese traditional medicine of Polygonati Rhizoma. It possesses the dual function as both medicine and food. Its main chemical components are polysaccharides and saponins. In order to understand the biosynthesis pathway of polysaccharides and diosgenin in P. cyrtonema, the corresponding transcriptomic data were obtained by extracting and sequencing the RNA of four parts of P. cyrtonema, namely, leaves, stems, rhizomes and roots. By adopting BGISEQ-500 sequencing platform, 42.03 Gb data were retrieved. Subsequently, the de novo assembly was carried out by Trinity software to obtain 137 233 transcripts, of which 68.13% of unigenes were annotated in seven databases including KEGG, GO, NR, NT, SwissProt, Pfam and KOG. Transcripts that may be involved in the biosynthesis of polysaccharides and diosgenin were analyzed by data mining. With help of qPCR, we validated expression data of four genes that were possibly involved in the biosynthesis of target metabolites. This experiment provides data for the study of biosynthetic pathways of P. cyrtonema secondary metabolites and the clarification of related structural gene functions.
Biosynthetic Pathways ; Diosgenin/metabolism* ; Gene Expression Profiling ; Phytochemicals/biosynthesis* ; Polygonatum/metabolism* ; Polysaccharides/biosynthesis* ; Transcriptome