Three-liquid-phase extraction of diosgenin and steroidal saponins from fermentation of Dioscorea zingibernsis C. H. Wright

Identification of genetic variants controlling diosgenin content in Dioscorea zingiberensis tuber by genome-wide association study

BACKGROUND

Diosgenin is an important steroidal precursor renowned for its diverse medicinal uses. It is predominantly sourced from Dioscorea species, particularly Dioscorea zingiberensis. Dioscorea zingiberensis has an ability to accumulate 2-16% diosgenin in its rhizomes. In this study, a diverse population of 180 D. zingiberensis accessions was used to evaluate the genomic regions associated with diosgenin biosynthesis by the genome wide association study approach (GWAS).

RESULTS

The whole population was characterized for diosgenin contents from tubers by gas chromatography mass spectrometry. The individuals were genotyped by the genotyping-by-sequencing approach and 10,000 high-quality SNP markers were extracted for the GWAS. The highest significant marker-trait-association was observed as an SNP transversion (G to T) on chromosome 10, with 64% phenotypic variance explained. The SNP was located in the promoter region of CYP94D144 which is a member of P450 gene family involved in the independent biosynthesis of diosgenin from cholesterol. The transcription factor (TF) binding site enrichment analysis of the promoter region of CYP94D144 revealed NAC TF as a potential regulator. The results were further validated through expression profiling by qRT-PCR, and the comparison of high and low diosgenin producing hybrids obtained from a bi-parental population.

CONCLUSIONS

This study not only enhanced the understanding of the genetic basis of diosgenin biosynthesis but also serves as a valuable reference for future genomic investigations on CYP94D144, with the aim of augmenting diosgenin production in yam tubers.

Process optimization for fermented siwu decoction by multi-index-response surface method and exploration of the effects of fermented siwu decoction on the growth, immune response and resistance to Vibrio harveyi of Pacific white shrimp (Litopenaeus vannamei)

The purpose of this study was to explore the optimal fermentation technology of Chinese herbal medicine formula-Siwu Decoction and the effects of fermented Siwu Decoction (FSW) on the growth performance, immune response, intestinal microflora and anti microbial ability of Litopenaeus vannamei. Response to surface methodology (RSM) was used to optimize the fermentation process of Siwu Decoction. The optimal fermentation conditions were obtained as follows: inoculation amount of mixed strains was 4.5%, fermentation time was 36 h, and the ratio of material to liquid was 20%. A total of 1260 shrimps were selected and divided into seven groups, three in parallel in each group. The dietary level of each group was as follows: Control （No additions）, USW1 (0.2% unfermented herbal medicine), USW2 (0.5% unfermented herbal medicine), USW3 (0.8% unfermented herbal medicine), FSW1 (0.2% fermented herbal medicine), FSW2 (0.5% fermented herbal medicine), FSW3 (0.8% fermented herbal medicine). The immune response and antioxidant defense ability of hemocytes and intestine were measured at 21 and 42 days of feeding and the intestinal flora and growth performance were measured at 42 days of feeding, after that, a 7-day challenge test against Vibrio harveyi was conducted. The results showed that fermented Siwu Decoction significantly improved the growth performance and body composition of Litopenaeus vannamei; significantly increased the total number of hemocytes, phagocytic activity, antibacterial activity and bacteriolytic activity of Litopenaeus vannamei, and improved the antioxidant activity of Litopenaeus vannamei; the addition of fermented Siwu Decoction significantly increased the gene expression level of hemocytes and intestinal tract of Litopenaeus vannamei, and improved the antioxidant activity of Litopenaeus vannamei. The abundance of Bacillus increased, while the abundance of Vibrio decreased. After Vibrio harveyi challenge, the cumulative mortality of FSW group was significantly lower than that of control group. Fermented Siwu Decoction may be a potential physiological enhancer in aquaculture, and can be widely used in aquaculture.

Three-liquid-phase salting-out extraction of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)-rich oils from Euphausia superba

The TLPSOES parameters were optimized by response surface methodology using Box-Behnken design, which were 16.5% w/w of ammonium citrate, 17.5% w/w of ethanol, and 46% w/w of n-hexane at 70 min of stirring time. Under optimized conditions the extraction efficiency attained was 90.91 ± 0.97% of EPA, 90.02 ± 1.04% of DHA, and 91.85 ± 1.11% of KO in the top n-hexane phase. The highest extraction efficiency of proteins and flavonoids, i.e. 88.34 ± 1.35% and 79.67 ± 1.13%, was recorded in the solid interface and ethanol phase, respectively. The KO extracted by TLPSOES system consisted of lowest fluoride level compared to the conventional method and whole wet krill biomass. The TLPSOES is a potential candidate for nutraceutical industry of KO extraction from wet krill biomass.

A Highly Efficient Three-Liquid-Phase-Based Enzymatic One-Pot Multistep Reaction System with Recoverable Enzymes for the Synthesis of Biodiesel

A three-liquid-phase system (TLPS) was developed and used as a novel enzymatic one-pot multistep reaction (EOMR) system. In this system, lipase and phospholipase were enriched in a single liquid phase with a high recovery (ca. 98%) and then used for the simultaneous catalysis of mutually inhibiting and interfering reactions (hydrolysis of phospholipids and glyceride in crude oil). A novel emulsion containing the two dispersed droplets (W₂/O/W₂ and W₁/W₂ emulsion structures) could be the key reason for this phenomenon because the emulsion system not only provided a new catalytic interface but also relieved the product inhibition. As a result, the content of free fatty acid (main hydrolysate of the glyceride) and the removal of phospholipid from the crude oil could be increased to 96 and 95%, respectively, within 1 h. The product obtained from the EOMR was directly used in the production of biodiesel via enzymatic esterification, and the content of fatty acid methanol ester could be increased to 93% within 2 h. Furthermore, the enzymes in the middle phase could also be reused, at least for eight rounds without significant loss in catalytic efficiency. Therefore, the TLPS could be considered as an ideal catalytic platform for the EOMR.

Evaluation of antioxidant, anti-inflammatory and anticancer activities of diosgenin enriched Paris polyphylla rhizome extract of Indian Himalayan landraces

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional medicinal plants have gained attention as a potential therapeutic agent to combat cancer and inflammation. Diosgenin rich fresh extracts of Paris polyphylla rhizome from Indian Himalaya is traditionally used as wound healing, anti-bleeding, anti-inflammatory and anti-cancer agent by the folk healers.

AIM OF THE STUDY

Present study was aimed to prepare two types of extracts from Paris polyphylla rhizome of Indian Himalayan landraces - 1. ethanolic extract of Paris polyphylla rhizome (EEPPR) and 2. Diosgenin enriched Paris polyphylla rhizome extract (DPPE), quantification of diosgenin content, and to evaluate their in vitro anti-oxidant, in vivo anti-inflammatory and in vitro cytotoxicity and anti-cancer activities of the DPPE.

MATERIALS AND METHODS

Diosgenin content of EEPPR was quantified through GC-MS while diosgenin content of DPPE was quantified through HPTLC, and the diosgenin yield from EEPPR and DPPE were compared. In vitro antioxidant activities of DPPE were performed using DPPH, NOD, RP and SOD assay while in vivo anti-inflammatory activity of DPPE were evaluated in dextran induced hind paw edema in rats. In vitro cytotoxicity and anti-cancer activities of DPPE were evaluated in human breast cancer cell lines (MCF-7, MDA-MB-231), cervical cancer cell lines (HeLa) and Hep-2 cell lines.

RESULTS

EEPPR obtained through cold extraction method using 70% ethanol showed maximum diosgenin content of 17.90% quantified through GC-MS while similar compounds pennogenin (3.29%), 7β-Dehydrodiosgenin (1.90%), 7-Ketodiosgenin acetate (1.14%), and 7 β-hydroxydiosgenin (0.55%) were detected in low concentration, and thus confirmed diosgenin as major and lead phytochemical. However, DPPE obtained through both cold and repeated hot extraction with the same solvent (70% ethanol) showed diosgenin content of 60.29% which is significantly higher (p < 0.001) than the diosgenin content in EEPPR. DPPE demonstrated significant in vitro antioxidant activities by dose-dependently quenched (p < 0.001) SOD free radicals by 76.66%, followed by DPPH (71.43%), NOD (67.35%), and RP (63.74%) at a max concentration of 2 μg/μl of ascorbic acid and test drugs with remarkable IC50 values (p < 0.01). Further, DPPE also showed potent anti-inflammatory activities by dose-dependently suppressed dextran induced paw edema in rats (p < 0.01) from 2 h to 4 h. DPPE suppressed the proliferation of MCF-7, MDA-MB-231, Hep-2 and HeLa cell lines. Maximum activity was observed in MCF-7 cells. The DPPE also induced apoptosis in MCF-7 cell lines as measured by AO/PI and DAPI staining, as well as DNA laddering, cell cycle analysis and phosphatidylserine externalization assay. The growth-inhibitory effect of DPPE on MCF-7 breast cancer cells was further confirmed from the colony-formation assay. DPPE upregulated expression of Bax and downregulated Bcl-2 and survivin mRNA transcripts.

CONCLUSION

DPPE obtained through both cold and repeated hot extraction using ethanol showed significantly higher content of diosgenin than the diosgenin content detected in EEPPR. However, diosgenin yield of both the extracts (EEPPR & DPPE) clearly confirmed diosgenin as major and lead phytochemical of Paris polyphylla rhizome of Indian Himalayan landraces. Further, DPPE also demonstrated potent in vitro anti-oxidative and in vivo anti-inflammatory activities and showed in vitro cytotoxicity and significant anti-cancer (apoptosis) effects in MCF-7 breast cancer cells.

Salting-out extraction of ginsenosides from the enzymatic hydrolysates of Panax quinquefolium based on ethanol/sodium carbonate system

Background

Salting-out extraction (SOE) had been developed as a special branch of aqueous two-phase system recently. So far as we know, few reports involved in extracting ginsenosides with SOE because of the lower recovery caused by the unique solubility and surface activity of ginsenosides. A new SOE method for rapid pretreatment of ginsenosides from the enzymatic hydrolysates of Panax quinquefolium was established in this article.

Methods

The SOE system comprising ethanol and sodium carbonate was selected to extract ginsenosides from the enzymatic hydrolysates of Panax quinquefolium, and HPLC was applied to analyze the ginsenosides.

Results

The optimized extraction conditions were as follows: the aqueous two-phase extraction system comprising ethanol, sodium carbonate, ethanol concentration of 41.51%, and the mass percent of sodium carbonate of 7.9% in the extraction system under the experimental condition. Extraction time had minor influence on extraction efficiency of ginsenosides. The results also showed that the extraction efficiencies of three ginsenosides were all more than 90.0% only in a single step.

Conclusion

The proposed method had been successfully applied to determine ginsenosides in enzymatic hydrolysate and demonstrated as a powerful technique for separating and purifying ginsenosides in complex samples.

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Salting-out extraction of ginsenosides was realized using ethanol/salt aqueous two-phase system.

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The factors influencing the extraction efficiency of ginsenosides were investigated.

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The high recovery of ginsenosides was obtained only in a single step.

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The extraction was successfully applied to determine ginsenosides in enzymatic hydrolysate.

The Application of Aqueous Two-phase System in the Extraction of Natural Products from Chinese Herbal Medicine: A Review

Background:

In the past decades, Chinese herbal medicine has attracted worldwide attention because they contain a variety of active ingredients which are beneficial to human health. As a result, there is a growing interest in the extraction of these substances. However, traditional extraction methods not only need a large amount of extractant, but are also time-consuming, moreover, the extraction efficiency is extremely poor and tedious purification steps are required to purify the crude extract. Thus, researchers hope to find an alternative method for the extraction of these components and the aqueous two-phase system (ATPS) seems to be one.

Objective:

This review focuses on introducing the properties of the aqueous two-phase system and summarizing the application of ATPS in the extraction of natural products. Meanwhile, this review also provided a guideline to researchers who wish to design a suitable ATPS for a specific target and how to amplify it to industrial-scale.

Highly Efficient and Enzyme-Recoverable Method for Enzymatic Concentrating Omega-3 Fatty Acids Generated by Hydrolysis of Fish Oil in a Substrate-Constituted Three-Liquid-Phase System

A novel three-liquid-phase system which contained fish oil as the nonpolar phase was developed for the lipase-based hydrolysis of fish oil and subsequent enrichment of the omega-3 polyunsaturated fatty acids (n-3 PUFA) in the glyceride fraction of the fish oil. In comparison with the traditional oil/water system, the enrichment factor of n-3 PUFA in this system was increased by 363.4% as a result of a higher dispersity, higher selectivity of the lipase for the other fatty acids except for n-3PUFA, and relief of product inhibition. The content of n-3 PUFA in the glyceride fraction could be concentrated to 67.97% by repeated hydrolysis after removing the free fatty acids. Furthermore, the lipase could be reused for at least eight rounds. This method would be an ideal approach for enriching n-3 PUFA because it is cost-effective, low in toxicity, and easily scaled up.

Dioscorea nipponica Makino: a systematic review on its ethnobotany, phytochemical and pharmacological profiles

Dioscorea nipponica Makino is a perennial twining herbs belonging to the family Dioscoreaceae, which is mainly distributed in the northeastern, northern, eastern and central regions of China. Traditionally, the rhizome of this herb has been commonly used by Miao and Meng ethnic groups of China to treat rheumatoid arthritis, pain in the legs and lumbar area, Kashin Beck disease, bruises, sprains, chronic bronchitis, cough and asthma. Modern pharmacological studies have discovered that this herb possesses anti-tumor, anti-inflammatory, anti-diuretic, analgesic, anti-tussive, panting-calming and phlegm-dispelling activities, along with enhancing immune function and improving cardiovascular health. In recent years, both fat-soluble and water-soluble steroidal saponins were isolated from the rhizomes of D. nipponica using silica gel column chromatography, thin layer chromatography and high performance liquid chromatography methods. Saponin and sapogenins are mainly responsible for most of the pharmacological effects of this plant. Further, the chemical components of the aboveground parts contain more than 10 kinds of phenanthrene derivatives. The present review summarizes the knowledge concerning the geographical distribution, chemical composition, pharmacological effects, toxicology studies and clinical applications of D. nipponica.

A Triple Salting-Out Effect is Required for the Formation of Ionic-Liquid-Based Aqueous Multiphase Systems

Novel aqueous multiphase systems (MuPSs) formed by quaternary mixtures composed of cholinium-based ionic liquids (ILs), polymers, inorganic salts, and water are reported herein. The influence of several ILs, polymers, and salts was studied, demonstrating that a triple salting-out is a required phenomenon to prepare MuPSs. The respective phase diagrams and "tie-surfaces" were determined, followed by the evaluation of the effect of temperature. Finally, the remarkable ability of IL-based MuPSs to selectively separate mixtures of textile dyes is shown.

Safety investigation on total steroid saponins extracts from Dioscorea zingiberensis C.H. Wright: Sub-acute and chronic toxicity studies on dogs

Sub-acute and chronic toxic effects of total steroidal saponins (TSSN) extracts from Dioscorea zingiberensis C.H. Wright on various internal organs and biochemical indicators have never been studied before and this study is the first of its kind to demonstrate sub-acute and chronic toxicities of TSSN on dogs. Administration of TSSN extracts at doses up to 3000 mg/Kg daily for 14 days, no biochemical and organ changes were observed on the experimental groups of dogs. Further, chronic toxicity study through oral administration of TSSN extracts at the gradual doses of 50, 250 and 500 mg/Kg for 90 days followed by a 2-week recovery assay revealed absence of significant architectural and morphological changes in internal organs which were confirmed through histopathological examination and merely no significant alteration in the biochemical indicators including hematologic and urine analysis and electrocardiogram compared to the control dogs. This toxicological evaluation came across with the finding that the herbal preparation can be considered as nontoxic and animals could tolerate the extracts at doses up to 500 mg/Kg with LD₅₀ greater than 3000 mg/Kg. It may serve as a preliminary scientific evidence for further therapeutic investigations.

Low pressure steam expansion pretreatment as a competitive approach to improve diosgenin yield and the production of fermentable sugar from Dioscorea zingiberensis C.H. Wright

Development of efficient pretreatment methods which can disrupt the peripheral lignocellulose and even the parenchyma cells is of great importance for production of diosgenin from turmeric rhizomes. It was found that low pressure steam expansion pretreatment (LSEP) could improve the diosgenin yield by more than 40% compared with the case without pretreatment, while simultaneously increasing the production of fermentable sugar by 27.37%. Furthermore, little inhibitory compounds were produced in LSEP process which was extremely favorable for the subsequent biotransformation of fermentable sugar to other valuable products such as ethanol. Preliminary study showed that the ethanol yield when using the fermentable sugar as carbon source was comparable to that using glucose. The liquid residue of LSEP treated turmeric tuber after diosgenin production can be utilized as a quality fermentable carbon source. Therefore, LSEP has great potential in industrial application in diosgenin clean production and comprehensive utilization of turmeric tuber.

Substrate-constituted three-liquid-phase system: a green, highly efficient and recoverable platform for interfacial enzymatic reactions

Using substrate (oil) as one phase, a three-liquid-phase system was fabricated, wherein the highly efficient interfacial enzymatic hydrolysis of oil toward the production of fatty acids could be readily achieved.

Quality control and identification of steroid saponins from Dioscorea zingiberensis C. H. Wright by fingerprint with HPLC-ELSD and HPLC-ESI-Quadrupole/Time-of-fight tandem mass spectrometry

In this study, a fingerprint of steroid saponins, the major bioactive constituents in the crude extracts from Dioscorea zingiberensis C. H. Wright (DZW), has been established for the first time by combined use of the following two methods: high-performance liquid chromatography coupled with evaporative light scattering detector (HPLC-ELSD) and the simultaneous characterization of the steroid saponins by high-performance liquid chromatography coupled with electrospray ionization-mass spectrometry and quadrupole tandem time-of-fight mass analyzers detection (HPLC-ESI-Q/TOF). All HPLC analyses were carried out on a Welchrom C18 column (250mm×4.6mm I.D., 5μm) with a mobile phase composed of water and acetonitrile under gradient elution. There were 68 common characteristic peaks in the fingerprints, in which 12 of them were confirmed by comparing their mass spectra and retention times with those of the reference compounds. In order to identify other unknown peaks, their fragmentation behaviors characteristic of the major groups of steroid saponins from DZW with six types of aglycone skeletons were discussed in detail, and possible MS/MS fragmentation pathways were proposed for aiding the structural identification of these components. According to the summarized fragmentation patterns, these peaks were tentatively assigned by matching their empirical molecular formula with those of the published compounds, or by elucidating their quasi-molecular ions and fragment ions referring to available literature information when the reference standards were unavailable. As a result, 22 new steroid saponins were found in DZW for the first time. In addition, the quantitative analysis of the nine (except for the reference compounds A, B, and C) known peaks was accomplished at the same time which indicated that there was a great variability in the amount of these active compounds in different batches in the crude extracts. This approach could demonstrate that the fingerprint could be considered to be a suitable tool to comprehensively improve the quality control of DZW. The identification and structural elucidation of the peaks in the fingerprint may provide important experimental data for further pharmacological and clinical researches.

Preparative isolation and purification of five steroid saponins from Dioscorea zingiberensis C.H.Wright by counter-current chromatography coupled with evaporative light scattering detector

A counter-current chromatography (CCC) method was successfully applied to separate and purify steroid saponins from the traditional Chinese medicine Dioscorea zingiberensis C.H.Wright for the first time. Ethyl acetate-n-butanol-methanol-water (4:1:2:4, v/v) was used as the two-phase solvent system, and evaporative light scattering detector (ELSD) was used as the detector in this method. The method separated in a single run the following five steroid saponins: 26-O-β-d-glucopyranosyl-(25R)-furost-5-en-3β, 22ζ, 26-triol-3-O-[β-d-glucopyranosyl-(1→3)-β-d-glucopyranol-(1→4)-α-l-rhamnopyranosyl-(1→2)]-β-d-glucopyranoside (Compound A); 26-O-β-d-glucopyranosyl-(25R)-furost-5-en-3β, 22ζ, 26-triol-3-O-[β-d-glucopyranosyl(1→3)-α-l-rhamnopyranosyl(1→2)]-β-d-glucopyranoside (Compound B); 26-O-β-d-glucopyranosyl-(25R)-furost-5-en-3β, 22ζ, 26-triol-3-O-[α-l-rhamnopyranosyl(1→4)]-β-d-glucopyranoside (Compound C); 26-O-β-d-glucopyranosyl-(25R)-furost-5, 20(22)-diene-3β, 26-diol-3-O-{α-l-rhamnopyranosyl-(1→4)-[β-d-glucopyranosyl-(1→3)-β-d-glucopyranosyl-(1→2)]}-β-d-glucopyranoside (Compound D); and 26-O-β-d-glucopyranosyl-(25R)-furost-5, 20(22)-diene-3β, 26-diol-3-O-[β-d-glucopyranosyl-(1→4)-α-l-rhamnopyranosyl(1→2)]-β-d-glucopyranoside (Compound E). Their structural identification of the five steroid saponins was performed by means of ESI-MS, and (13)C NMR.

Novel method utilizing microbial treatment for cleaner production of diosgenin from Dioscorea zingiberensis C.H. Wright (DZW)

A novel method utilizing microbial treatment for cleaner production of diosgenin from Dioscorea zingiberensis C.H. Wright (DZW) was presented. A new Bacillus pumilus HR19, which has the great ability to secrete pectinase, was screened and applied in the microbial treatment. Low-pressure steam expansion pretreatment (LSEP) was employed in advance to assist microbial treatment efficiently in releasing saponins, which are the precursors of diosgenin. Compared with the traditional process of acid hydrolysis, this novel process reduced the consumptions of water, acid and organic solvent by more than 92.5%, 97.0%, 97.0%, respectively, while simultaneously increasing the diosgenin yield by 6.21%. In addition, the microbial treatment was more efficient than enzymatic treatment, which arised from that microorganisms could be induced to secrete related enzymes by the compositions of DZW and relieve product inhibition by utilizing enzyme hydrolysates.

Deltonin, a steroidal saponin, inhibits colon cancer cell growth in vitro and tumor growth in vivo via induction of apoptosis and antiangiogenesis

Deltonin, a steroidal saponin, isolated from Dioscorea zingiberensis Wright (DZW), has shown high-cytotoxic activity in cancer cells. However, its mechanisms and in vivo anti-cancer effects remain unknown. In the present study, we evaluated the effects and explored the anti-tumor mechanisms of deltonin on a panel of colon cancer cell lines and in a mouse model of murine colon cancer C26. Deltonin had more cytotoxic effect on C26 cells than 5-fluorouracil had, promoting dramatic G2-M phase arrest and apoptosis in C26 cells in a concentration-dependent manner; oral administration of deltonin significantly inhibited the tumor growth and prolonged survival of the tumor bearing mice. The deltonin treatment caused a noticeable apoptosis in tumor tissue, which associated with increased levels of Bax, activated caspase-3, caspase-9, and cleaved poly (ADPribose) polymerase, decreased pro-caspase-8, pro-caspase-9, Bcl-2 expression levels and extracellular signal-regulated kinase-1/2 activity; and dose-dependently inhibit angiogenesis. In conclusion, the findings in this study demonstrated that deltonin is an effective natural agent for cancer therapy, which may be mediated, in part, by induction of apoptosis, as well as involve mitogen-activated protein kinase pathways, and inhibition of angiogenesis.