Classification of glycosidases that hydrolyze the specific positions and types of sugar moieties in ginsenosides

Preparation of in vivo intermediate metabolites of soybean saponins with improved bioactivity by in vitro deacetylation and deglucosylation

Unlike natural soyasaponins and their aglycones formed by enzymatic hydrolysis in the human intestine, in vivo intermediate soyasaponin metabolites are difficult to prepare. Therefore, the pharmacological activities of in vivo intermediate soyasaponins remain uninvestigated. Herein, in vivo intermediate soyasaponins with purities of >90% were prepared by in vitro deacetylation (alkaline treatment) and deglucosylation (β-glucosidase treatment) of natural soyasaponins using preparative high-performance liquid chromatography. These compounds exhibited higher anti-inflammatory and antioxidant activities than natural soyasaponins in in vitro bioassays, suggesting that the intermediate soyasaponins can be used as improved bioactive food supplements. To the best of our knowledge, this is the first study reporting the in vitro preparation and bioassays of in vivo intermediate soyasaponin metabolites formed in the human intestine.

Exploring the antimicrobial activity of rare ginsenosides and the progress of their related pharmacological effects

BACKGROUND

Panax ginseng C. A. Mey is a precious medicinal resource that could be used to treat a variety of diseases. Saponins are the most important bioactive components of, and rare ginsenosides (Rg3, Rh2, Rk1 and Rg5, etc.) refer to the chemical structure changes of primary ginsenosides through dehydration and desugarization reactions, to obtain triterpenoids that are easier to be absorbed by the human body and have higher activity.

PURPOSE

At present, the research of P. ginseng. is widely focused on anticancer related aspects, and there are few studies on the antibacterial and skin protection effects of rare ginsenosides. This review summarizes the rare ginsenosides related to bacterial inhibition and skin protection and provides a new direction for P. ginseng research.

METHODS

PubMed and Web of Science were searched for English-language studies on P. ginseng published between January 2002 and March 2024. Selected manuscripts were evaluated manually for additional relevant references. This review includes basic scientific articles and related studies such as prospective and retrospective cohort studies.

CONCLUSION

This paper summarizes the latest research progress of several rare ginsenosides, discusses the antibacterial effect of rare ginsenosides, and finds that ginsenosides can effectively protect the skin and promote wound healing during use, so as to play an efficient antibacterial effect, and further explore the other medicinal value of ginseng. It is expected that this review will provide a wider understanding and new ideas for further research and development of P. ginseng drugs.

Advancements in enzymatic biotransformation and bioactivities of rare ginsenosides: A review

Ginsenoside, the principal active constituent of ginseng, exhibits enhanced bioavailability and medicinal efficacy in rare ginsenosides compared to major ginsenosides. Current research is focused on efficiently and selectively removing sugar groups attached to the major ginsenoside sugar chains to convert them into rare ginsenosides that meet the demands of medical industry and functional foods. The methods for preparing rare ginsenosides encompass chemical, microbial, and enzymatic approaches. Among these, the enzyme conversion method is highly favored by researchers due to its exceptional specificity and robust efficiency. This review summarizes the biological activities of different rare ginsenosides, explores the various glycosidases used in the biotransformation of different major ginsenosides as substrates, and elucidates their respective corresponding biotransformation pathways. These findings will provide valuable references for the development, utilization, and industrial production of ginsenosides.

Engineering UDP-Glycosyltransferase UGTPg29 for the Efficient Synthesis of Ginsenoside Rg3 from Protopanaxadiol

Rare ginsenosides Rg3 and Rh2, which exhibit diverse pharmacological effects, are derivatives of protopanaxadiol (PPD). UDP-glycosyltransferases, such as the M315F variant of Bs-YjiC (Bs-YjiCm) from Bacillus subtilis and UGTPg29 from Panax ginseng, can efficiently convert PPD into Rh2 and Rh2 into Rg3, respectively. In the present study, the N178I mutation of Bs-YjiCm was introduced, resulting in an increase in Rh2 production. UDP-glycosyltransferase UGTPg29 was then engineered to improve its robustness through semi-rational design. The variant R91M/D184M/A287V/A342L, which indicated desirable stability and activity, was utilized in coupling with the N178I variant of Bs-YjiCm and sucrose synthase AtSuSy from Arabidopsis thaliana to set up a "one-pot" three-enzyme reaction for the biosynthesis of Rg3. The influential factors, including the ratio and concentration of UDP-glycosyltransferases, pH, and the concentrations of UDP, sucrose, and DMSO, were optimized. On this basis, a fed-batch strategy was adopted to achieve a Rg3 yield as high as 12.38 mM (9.72 g/L) with a final yield of 68.78% within 24 h. This work may provide promising UDP-glycosyltransferase candidates for ginsenoside biosynthesis.

A Versatile β-Glycosidase from Petroclostridium xylanilyticum Prefers the Conversion of Ginsenoside Rb3 over Rb1, Rb2, and Rc to Rd by Its Specific Cleavage Activity toward 1,6-Glycosidic Linkages

To convert ginsenosides Rb1, Rb2, Rb3, and Rc into Rd by a single enzyme, a putative β-glycosidase (Pxbgl) from the xylan-degrading bacterium Petroclostridium xylanilyticum was identified and used. The kcat/Km value of Pxbgl for Rb3 was 18.18 ± 0.07 mM-1/s, which was significantly higher than those of Pxbgl for other ginsenosides. Pxbgl converted almost all Rb3 to Rd with a productivity of 5884 μM/h, which was 346-fold higher than that of only β-xylosidase from Thermoascus aurantiacus. The productivity of Rd from the Panax ginseng root and Panax notoginseng leaf was 146 and 995 μM/h, respectively. Mutants N293 K and I447L from site-directed mutagenesis based on bioinformatics analysis showed an increase in specific activity of 29 and 7% toward Rb3, respectively. This is the first report of a β-glycosidase that can simultaneously remove four different glycosyls at the C-20 position of natural PPD-type ginsenosides and produce Rd as the sole product from P. notoginseng leaf extracts with the highest productivity.

Conversion of notoginsenoside R1 to 3β,12β-dihydroxydammar-(E)-20(22),24-diene-6-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside by Lactiplantibacillus plantarum S165 enhanced protective effects of LPS-induced intestinal epithelial barrier injury in Caco-2 cells

AIMS

Microbial transformation to modify saponins and enhance their biological activities has received increasing attention in recent years. This study aimed to screen the strain that can biotransform notoginsenoside R1, identify the product and study its biological activity.

METHODS AND RESULTS

A lactic acid bacteria strain S165 with glycosidase-producing activity was isolated from traditional Chinese fermented foods, which was identified and grouped according to API 50 CHL kit and 16S rDNA sequence analysis. Subsequently, notoginsenoside R1 underwent a 30-day fermentation period by the strain S165, and the resulting products were analyzed using High-performance liquid chromatography (HPLC), Ultra-performance liquid chromatography (UPLC)-mass spectrometry (MS)/MS, and 13C-Nuclear magnetic resonance (NMR) techniques. Employing a model of Lipopolysaccharide (LPS)-induced damage to Caco-2 cells, the damage of Caco-2 cells was detected by Hoechst 33 258 staining, and the activity of notoginsenoside R1 biotransformation product was investigated by CCK-8 and western blotting assay. The strain S165 was identified as Lactiplantibacillus plantarum and was used to biotransform notoginsenoside R1. Through a 30-day biotransformation, L. plantarum S165 predominantly converts notoginsenoside R1 into 3β,12β-dihydroxydammar-(E)-20(22),24-diene-6-O-β-D-xylopyranosyl-(1→2)-β-D-glucopyranoside, temporarily named notoginsenoside T6 (NGT6) according to HPLC, UPLC-MS/MS, and 13C-NMR analysis. Results from CCK-8 and Hoechst 33258 staining indicated that the ability notoginsenoside T6 to alleviate the intestinal injury induced by LPS in the Caco-2 cell was stronger than that of notoginsenoside R1. In addition, Western blotting result showed that notoginsenoside T6 could prevent intestinal injury by protecting tight junction proteins (Claudin-1, Occludin, and ZO-1).

CONCLUSION

Notoginsenoside R1 was biotransformed into the notoginsenoside T6 by L. plantarum S165, and the biotransformed product showed an enhanced intestinal protective effect in vitro.

Ginseng fermentation solution affects the gut microbiota in zebrafish with alcoholic liver disease via PI3K/Akt pathway

BACKGROUND

Ginsenosides have received increased amounts of attention due to their ability to modulate the intestinal flora, which may subsequently alleviate alcoholic liver disease (ALD). The effects of ginseng fermentation solution (GFS) on the gut microbiota and metabolism in ALD patients have not been explored.

PURPOSE

This research aimed to explore the regulatory effect of GFS on ALD both in vitro and in vivo.

METHOD

This study assessed the anti-ALD efficacy of GFS using an LO2 cell model and a zebrafish model. Untargeted metabolomics was used for differentially abundant metabolite analysis, and high-throughput 16S rRNA sequencing was used to examine the effect of GFS on ALD.

RESULTS

The LO2 cell line experiments demonstrated that GFS effectively mitigated alcohol-induced oxidative stress and reduced apoptosis by upregulating PI3K and Bcl-2 expression and decreasing the levels of malondialdehyde, total cholesterol, and triglycerides. In zebrafish, GFS improved morphological and physiological parameters and diminished oxidative stress-induced ALD. Meanwhile, the results from Western blotting indicated that GFS enhanced the expression of PI3K, Akt, and Bcl-2 proteins while reducing Bax protein expression, thereby ameliorating the ALD model in zebrafish. Metabolomics data revealed significant changes in a total of 46 potential biomarkers. Among them, metabolites such as prostaglandin F2 alpha belong to arachidonic acid metabolism. In addition, GFS also partly reversed the imbalance of gut microbiota composition caused by alcohol. At the genus level, alcohol consumption elevated the presence of Flectobacillus, Curvibacter, among others, and diminished Elizabethkingia within the intestinal microbes of zebrafish. Conversely, GFS reversed these effects, notably enhancing the abundance of Proteobacteria and Archaea. Correlation analyses further indicated a significant negative correlation between prostaglandin F2 alpha, 11,14,15-THETA, Taurocholic acid and Curvibacter.

CONCLUSION

This study highlights a novel mechanism by which GFS modulates anti-ALD activity through the PI3K/Akt signalling pathway by influencing the intestinal flora-metabolite axis. These results indicate the potential of GFS as a functional food for ALD treatment via modulation of the gut flora.

Biotransformation of Ginsenoside Rb1 to Ginsenoside Rd and 7 Rare Ginsenosides Using Irpex lacteus with HPLC-HRMS/MS Identification

The biotransformation of ginsenosides using microorganisms represents a promising and ecofriendly approach for the production of rare ginsenosides. The present study reports on the biotransformation of ginsenoside Rb1 using the fungus Irpex lacteus, resulting in the production of ginsenoside Rd and seven rare ginsenosides with novel structures. Employing high-performance liquid chromatography coupled with high-resolution tandem mass spectrometry, the identities of the transformation products were rapidly determined. Two sets of isomers with molecular weights of 980.56 and 962.55 were discovered among the seven rare ginsenosides, which were generated through the isomerization of the olefin chain in the protopanaxadiol (PPD)-type ginsenoside skeleton. Each isomer exhibited characteristic fragment ions and neutral loss patterns in their tandem mass spectra, providing evidence of their unique structures. Time-course experiments demonstrated that the transformation reaction reached equilibrium after 14 days, with Rb1 initially generating Rd and compound 5, followed by the formation of other rare ginsenosides. The biotransformation process catalyzed by I. lacteus was found to involve not only the typical deglycosylation reaction at the C-20 position but also hydroxylation at the C-22 and C-23 positions, as well as hydrogenation, transfer, and cyclization of the double bond at the C-24(25) position. These enzymatic capabilities extend to the structural modification of other PPD-type ginsenosides such as Rc and Rd, revealing the potential of I. lacteus for the production of a wider range of rare ginsenosides. The transformation activities observed in I. lacteus are unprecedented among fungal biotransformations of ginsenosides. This study highlights the application of a medicinal fungi-based biotransformation strategy for the generation of rare ginsenosides with enhanced structural diversity, thereby expanding the variety of bioactive compounds derived from ginseng.

Characterization of a novel cold-adapted GH1 β-glucosidase from Psychrobacillus glaciei and its application in the hydrolysis of soybean isoflavone glycosides

The novel β-glucosidase gene (pgbgl1) of glycoside hydrolase (GH) family 1 from the psychrotrophic bacterium Psychrobacillus glaciei sp. PB01 was successfully expressed in Escherichia coli BL21 (DE3). The deduced PgBgl1 contained 447 amino acid residues with a calculated molecular mass of 51.4 kDa. PgBgl1 showed its maximum activity at pH 7.0 and 40 °C, and still retained over 10% activity at 0 °C, suggesting that the recombinant PgBgl1 is a cold-adapted enzyme. The substrate specificity, Km, Vmax, and Kcat/Km for the p-Nitrophenyl-β-D-glucopyranoside (pNPG) as the substrate were 1063.89 U/mg, 0.36 mM, 1208.31 U/mg and 3871.92/s, respectively. Furthermore, PgBgl1 demonstrated remarkable stimulation of monosaccharides such as glucose, xylose, and galactose, as well as NaCl. PgBgl1 also demonstrated a high capacity to convert the primary soybean isoflavone glycosides (daidzin, genistin, and glycitin) into their respective aglycones. Overall, PgBgl1 exhibited high catalytic activity towards aryl glycosides, suggesting promising application prospects in the food, animal feed, and pharmaceutical industries.

Ginsenoside Rg3, enriched in red ginseng extract, improves lipopolysaccharides-induced suppression of brown and beige adipose thermogenesis with mitochondrial activation

Brown adipose tissue (BAT) which is a critical regulator of energy homeostasis, and its activity is inhibited by obesity and low-grade chronic inflammation. Ginsenoside Rg3, the primary constituent of Korean red ginseng (steamed Panax ginseng CA Meyer), has shown therapeutic potential in combating inflammatory and metabolic diseases. However, it remains unclear whether Rg3 can protect against the suppression of browning or activation of BAT induced by inflammation. In this study, we conducted a screening of ginsenoside composition in red ginseng extract (RGE) and explored the anti-adipogenic effects of both RGE and Rg3. We observed that RGE (exist 0.25 mg/mL of Rg3) exhibited significant lipid-lowering effects in adipocytes during adipogenesis. Moreover, treatment with Rg3 (60 μM) led to the inhibition of triglyceride accumulation, subsequently promoting enhanced fatty acid oxidation, as evidenced by the conversion of radiolabeled 3H-fatty acids into 3H-H2O with mitochondrial activation. Rg3 alleviated the attenuation of browning in lipopolysaccharide (LPS)-treated beige adipocytes and primary brown adipocytes by recovered by uncoupling protein 1 (UCP1) and the oxygen consumption rate compared to the LPS-treated group. These protective effects of Rg3 on inflammation-induced inhibition of beige and BAT-derived thermogenesis were confirmed in vivo by treating with CL316,243 (a beta-adrenergic receptor agonist) and LPS to induce browning and inflammation, respectively. Consistent with the in vitro data, treatment with Rg3 (2.5 mg/kg, 8 weeks) effectively reversed the LPS-induced inhibition of brown adipocyte features in C57BL/6 mice. Our findings confirm that Rg3-rich foods are potential browning agents that counteract chronic inflammation and metabolic complications.

Mutations in Glycosyltransferases and Glycosidases: Implications for Associated Diseases

Glycosylation, a crucial and the most common post-translational modification, coordinates a multitude of biological functions through the attachment of glycans to proteins and lipids. This process, predominantly governed by glycosyltransferases (GTs) and glycoside hydrolases (GHs), decides not only biomolecular functionality but also protein stability and solubility. Mutations in these enzymes have been implicated in a spectrum of diseases, prompting critical research into the structural and functional consequences of such genetic variations. This study compiles an extensive dataset from ClinVar and UniProt, providing a nuanced analysis of 2603 variants within 343 GT and GH genes. We conduct thorough MTR score analyses for the proteins with the most documented variants using MTR3D-AF2 via AlphaFold2 (AlphaFold v2.2.4) predicted protein structure, with the analyses indicating that pathogenic mutations frequently correlate with Beta Bridge secondary structures. Further, the calculation of the solvent accessibility score and variant visualisation show that pathogenic mutations exhibit reduced solvent accessibility, suggesting the mutated residues are likely buried and their localisation is within protein cores. We also find that pathogenic variants are often found proximal to active and binding sites, which may interfere with substrate interactions. We also incorporate computational predictions to assess the impact of these mutations on protein function, utilising tools such as mCSM to predict the destabilisation effect of variants. By identifying these critical regions that are prone to disease-associated mutations, our study opens avenues for designing small molecules or biologics that can modulate enzyme function or compensate for the loss of stability due to these mutations.

Molecular cloning, expression, purification, and characterization of Bacillus subtilis hydrolyzed ginsenoside Rc of α-L-arabinofuranosidase in Escherichia coli

The α-L-arabinofuranosidase enzyme plays a crucial role in the degradation of ginsenosides. In this study, we successfully cloned and expressed a novel α-L-arabinofuranosidase bsafs gene (1503 bp, 501 amino acids, 55 kDa, and pI = 5.4) belonging to glycosyl hydrolase (GH) family 51 from Bacillus subtilis genome in Escherichia coli BL21 cells. The recombinant protein Bsafs was purified using Ni2+ sepharose fastflow affinity chromatography and exhibited a specific activity of 2.91 U/mg. Bsafs effectively hydrolyzed the α-L-arabinofuranoside at C20 site of ginsenoside Rc to produce Rd as the product. The Km values for hydrolysis of pNP-α-L-arabinofuranoside (pNPαAraf) and ginsenoside Rc were determined as 0.74 and 4.59 mmol/L, respectively; while the Vmax values for these substrates were found to be 24 and 164 μmol/min/mg, respectively; furthermore, the Kcat values for these enzymes were calculated as 22.3 and 1.58 S-1 correspondingly.

Biosynthesis of palladium, platinum, and their bimetallic nanoparticles using rosemary and ginseng herbal plants: evaluation of anticancer activity

In this research, palladium (II) and platinum (II), as well as their bimetallic nanoparticles were synthesized using medicinal plants in an eco-friendly manner. Rosemary and Ginseng extracts were chosen due to their promising anticancer potential. The synthesized nanoparticles underwent characterization through FT-IR spectroscopy, DLS, XRD, EDX, SEM, and TEM techniques. Once the expected structures were confirmed, the performance of these nanoparticles, which exhibited an optimal size, was evaluated as potential anticancer agents through in vitro method on colon cancer cell lines (Ls180, SW480). MTT assay studies showed that the synthesized nanoparticles induced cell death. Moreover, real-time PCR was employed to investigate autophagy markers and the effect of nanoparticles on the apoptosis process, demonstrating a significant effect of the synthesized compounds in this regard.

Tomato root-associated Sphingobium harbors genes for catabolizing toxic steroidal glycoalkaloids

IMPORTANCE

Saponins are a group of plant specialized metabolites with various bioactive properties, both for human health and soil microorganisms. Our previous works demonstrated that Sphingobium is enriched in both soils treated with a steroid-type saponin, such as tomatine, and in the tomato rhizosphere. Despite the importance of saponins in plant-microbe interactions in the rhizosphere, the genes involved in the catabolism of saponins and their aglycones (sapogenins) remain largely unknown. Here we identified several enzymes that catalyzed the degradation of steroid-type saponins in a Sphingobium isolate from tomato roots, RC1. A comparative genomic analysis of Sphingobium revealed the limited distribution of genes for saponin degradation in our saponin-degrading isolates and several other isolates, suggesting the possible involvement of the saponin degradation pathway in the root colonization of Sphingobium spp. The genes that participate in the catabolism of sapogenins could be applied to the development of new industrially valuable sapogenin molecules.

Identification of Potential Mechanisms of Rk1 Combination with Rg5 in the Treatment of Type II Diabetes Mellitus by Integrating Network Pharmacology and Experimental Validation

In this study, we aimed to explore the potential targets and functional mechanisms of Rk1 combined with Rg5 (Rk1+Rg5) against type II diabetes mellitus (T2DM). Network pharmacology and molecular docking were used to predict and verify the targets and signaling pathways of Rk1+Rg5 against T2DM. The results were further confirmed by a db/db mouse model and a model using PA-induced L6 cells. According to network pharmacology, a total of 250 core targets of Rk1+Rg5 towards T2DM were identified; the insulin resistance signaling pathways were enriched by KEGG. Results of molecular docking indicated good binding affinity of Rk1 and Rg5 to Akt1. In vivo and in vitro studies further showed that Rk1+Rg5 is an inhibitor of skeletal muscle insulin resistance. The results showed that Rk1+Rg5 significantly improved the hyperglycemic state of db/db mice, alleviated dyslipidemia, and promoted skeletal muscle glucose uptake. This phenomenon was closely related to the alleviation of the insulin resistance in skeletal muscles. Finally, the combination activated the Akt signaling pathway and promoted GLUT4 translocation to the cell membrane for glucose uptake. Altogether, our findings, for the first time, demonstrate that the combination of Rk1 and Rg5 could be beneficial for anti-T2DM, possibly involving ameliorated insulin resistance.

Production of ginsenoside compound K from American ginseng extract by fed-batch culture of Aspergillus tubingensis

Compound K (C-K), one of the most bioactive ginsenoside, is produced by hydrolyzing the glycoside moieties of protopanaxadiol (PPD)-type glycosylated ginsenosides in the ginseng extract. To enhance the biotransformation of PPD-type ginsenosides in American ginseng extract (AGE) into C-K, the optimization of the feed type, concentration, and period for the carbon source sucrose and the reactant AGE was performed in fed-batch fermentation of Aspergillus tubingensis using a fermenter. The concentration (3.94 g/L) and productivity (27.4 mg/L/h) of C-K after feed optimization in fed-batch fermentation increased 3.1-fold compared to those (1.29 g/L and 8.96 mg/L/h) in batch fermentation, and a molar conversion of 100% was achieved. To the best of our knowledge, this is the first trial of fed-batch fermentation to convert ginseng extract into deglycosylated ginsenoside and the highest reported C-K concentration and productivity using ginseng extract via fermentation. After ethanol and resin treatments, C-K solids with purities of 59% and 96% were obtained from the fermentation broth as food- and pharmaceutical-grade products, respectively.

Structures, Biochemical Characteristics, and Functions of β-Xylosidases

The complete degradation of abundant xylan derived from plants requires the participation of β-xylosidases to produce the xylose which can be converted to xylitol, ethanol, and other valuable chemicals. Some phytochemicals can also be hydrolyzed by β-xylosidases into bioactive substances, such as ginsenosides, 10-deacetyltaxol, cycloastragenol, and anthocyanidins. On the contrary, some hydroxyl-containing substances such as alcohols, sugars, and phenols can be xylosylated by β-xylosidases into new chemicals such as alkyl xylosides, oligosaccharides, and xylosylated phenols. Thus, β-xylosidases shows great application prospects in food, brewing, and pharmaceutical industries. This review focuses on the molecular structures, biochemical properties, and bioactive substance transformation function of β-xylosidases derived from bacteria, fungi, actinomycetes, and metagenomes. The molecular mechanisms of β-xylosidases related to the properties and functions are also discussed. This review will serve as a reference for the engineering and application of β-xylosidases in food, brewing, and pharmaceutical industries.

β-Glucosidase and Its Application in Bioconversion of Ginsenosides in Panax ginseng

Ginsenosides are a group of bioactive compounds isolated from Panax ginseng. Conventional major ginsenosides have a long history of use in traditional medicine for both illness prevention and therapy. Bioconversion processes have the potential to create new and valuable products in pharmaceutical and biological activities, making them both critical for research and highly economic to implement. This has led to an increase in the number of studies that use major ginsenosides as a precursor to generate minor ones using β-glucosidase. Minor ginsenosides may also have useful properties but are difficult to isolate from raw ginseng because of their scarcity. Bioconversion processes have the potential to create novel minor ginsenosides from the more abundant major ginsenoside precursors in a cost-effective manner. While numerous bioconversion techniques have been developed, an increasing number of studies have reported that β-glucosidase can effectively and specifically generate minor ginsenosides. This paper summarizes the probable bioconversion mechanisms of two protopanaxadiol (PPD) and protopanaxatriol (PPT) types. Other high-efficiency and high-value bioconversion processes using complete proteins isolated from bacterial biomass or recombinant enzymes are also discussed in this article. This paper also discusses the various conversion and analysis methods and their potential applications. Overall, this paper offers theoretical and technical foundations for future studies that will be both scientifically and economically significant.

Combinatorial Enzymatic Catalysis for Bioproduction of Ginsenoside Compound K

Ginsenoside compound K (CK) is an emerging functional food or pharmaceutical product. To date, there are still challenges to exploring effective catalytic enzymes for enzyme-catalyzed manufacturing processes and establishing enzyme-catalyzed processes. Herein, we identified three ginsenoside hydrolases BG07 (glucoamylase), BG19 (β-glucosidase), and BG23 (β-glucosidase) from Aspergillus tubingensis JE0609 by transcriptome analysis and peptide mass fingerprinting. Among them, BG23 was expressed in Komagataella phaffii with a high volumetric activity of 235.73 U mL-1 (pNPG). Enzymatic property studies have shown that BG23 is an acidic (pH adaptation range of 4.5-7.0) and mesophilic (thermostable < 50 °C) enzyme. Moreover, a one-pot combinatorial enzyme-catalyzed strategy based on BG23 and BGA35 (β-galactosidase from Aspergillus oryzae) was established, with a high CK yield of 396.7 mg L-1 h-1. This study explored the ginsenoside hydrolases derived from A. tubingensis at the molecular level and provided a reference for the efficient production of CK.

Renal function protection and the mechanism of ginsenosides: Current progress and future perspectives

Nephropathy is a general term for kidney diseases, which refers to changes in the structure and function of the kidney caused by various factors, resulting in pathological damage to the kidney, abnormal blood or urine components, and other diseases. The main manifestations of kidney disease include hematuria, albuminuria, edema, hypertension, anemia, lower back pain, oliguria, and other symptoms. Early detection, diagnosis, and active treatment are required to prevent chronic renal failure. The concept of nephropathy encompasses a wide range of conditions, including acute renal injury, chronic kidney disease, nephritis, renal fibrosis, and diabetic nephropathy. Some of these kidney-related diseases are interrelated and may lead to serious complications without effective control. In serious cases, it can also develop into chronic renal dysfunction and eventually end-stage renal disease. As a result, it seriously affects the quality of life of patients and places a great economic burden on society and families. Ginsenoside is one of the main active components of ginseng, with anti-inflammatory, anti-tumor, antioxidant, and other pharmacological activities. A variety of monomers in ginsenosides can play protective roles in multiple organs. According to the difference of core structure, ginsenosides can be divided into protopanaxadiol-type (including Rb1, Rb3, Rg3, Rh2, Rd and CK, etc.), and protopanaxatriol (protopanaxatriol)- type (including Rg1, Rg2 and Rh1, etc.), and other types (including Rg5, Rh4, Rh3, Rk1, and Rk3, etc.). All of these ginsenosides showed significant renal function protection, which can reduce renal damage in renal injury, nephritis, renal fibrosis, and diabetic nephropathy models. This review summarizes reports on renal function protection and the mechanisms of action of these ginsenosides in various renal injury models.

Production of ginsenoside compound K by microbial cell factory using synthetic biology-based strategy: a review

Ginsenoside compound K (CK) is a major intestinal bacterial metabolite of the protopanaxadiol-type ginsenoside family that can be absorbed in the systemic circulation. CK possesses diverse and important pharmacological properties. The low production and high cost of traditional manufacturing methods based on the extraction and biotransformation of total ginsenosides from ginseng have limited their medical application. However, considerable progress has been made in the area of de novo CK production via microbial cell factories using synthetic biology-based strategies. By introducing key enzymes responsible for CK biosynthesis into microbial cells, CK was produced via a series of in vivo enzymatic reactions that utilize the inherent precursors in microbial cells. After systematic optimization using various metabolic engineering strategies, the yield of CK increased significantly and exceeded the traditional plant extraction-biotransformation method, implying the commercial feasibility of this approach. This review summarizes recent novel advancements in the production of CK using microbial cell factories.

Biotransformation of Platycosides, Saponins from Balloon Flower Root, into Bioactive Deglycosylated Platycosides

Platycosides, saponins from balloon flower root (Platycodi radix), have diverse health benefits, such as antioxidant, anti-inflammatory, anti-tussive, anti-cancer, anti-obesity, anti-diabetes, and whitening activities. Deglycosylated platycosides, which show greater biological effects than glycosylated platycosides, are produced by the hydrolysis of glycoside moieties in glycosylated platycosides. In this review, platycosides are classified according to the chemical structures of the aglycone sapogenins and also divided into natural platycosides, including major, minor, and rare platycosides, depending on the content in Platycodi radix extract and biotransformed platycosides. The biological activities of platycosides are summarized and methods for deglycosylation of saponins, including physical, chemical, and biological methods, are introduced. The biotransformation of glycosylated platycosides into deglycosylated platycosides was described based on the hydrolytic pathways of glycosides, substrate specificity of glycosidases, and specific productivities of deglycosylated platycosides. Methods for producing diverse and/or new deglycosylated platycosides are also proposed.

Progress in the Conversion of Ginsenoside Rb1 into Minor Ginsenosides Using β-Glucosidases

In recent years, minor ginsenosides have received increasing attention due to their outstanding biological activities, yet they are of extremely low content in wild ginseng. Ginsenoside Rb1, which accounts for 20% of the total ginsenosides, is commonly used as a precursor to produce minor ginsenosides via β-glucosidases. To date, many research groups have used different approaches to obtain β-glucosidases that can hydrolyze ginsenoside Rb1. This paper provides a compilation and analysis of relevant literature published mainly in the last decade, focusing on enzymatic hydrolysis pathways, enzymatic characteristics and molecular mechanisms of ginsenoside Rb1 hydrolysis by β-glucosidases. Based on this, it can be concluded that: (1) The β-glucosidases that convert ginsenoside Rb1 are mainly derived from bacteria and fungi and are classified as glycoside hydrolase (GH) families 1 and 3, which hydrolyze ginsenoside Rb1 mainly through the six pathways. (2) Almost all of these β-glucosidases are acidic and neutral enzymes with molecular masses ranging from 44-230 kDa. Furthermore, the different enzymes vary widely in terms of their optimal temperature, degradation products and kinetics. (3) In contrast to the GH1 β-glucosidases, the GH3 β-glucosidases that convert Rb1 show close sequence-function relationships. Mutations affecting the substrate binding site might alter the catalytic efficiency of enzymes and yield different prosapogenins. Further studies should focus on elucidating molecular mechanisms and improving overall performances of β-glucosidases for better application in food and pharmaceutical industries.

Shengmai san-derived compound prescriptions: A review on chemical constituents, pharmacokinetic studies, quality control, and pharmacological properties

BACKGROUND

Shengmai San Formula (SMS), composed of Ginseng Radix et Rhizoma, Ophiopogon Radix and Schisandra chinensis Fructus, was a famous formula in Tradition Chinese Medicine (TCM). With the expansion of clinical applications, SMS was developed to different dosage forms, including Shengmai Yin Oral liquid (SMY), Shengmai Capsule (SMC), Shengmai Granule (SMG), Shengmai Injection (SMI) and Dengzhan Shengmai Capsule (DZSMC). These above SMS-derived compound prescriptions (SSCPs) play an important role in the clinical treatment. This review is aimed to providing a comprehensive perspective of SSCP.

METHODS

The relevant literatures were collected from classical TCM books and a variety of databases, including PubMed, Google Scholar, Science Direct, Springer Link, Web of Science, China National Knowledge Infrastructure, and Wanfang Data.

RESULTS

The chemical constituents of SSCPs, arrived from the individual medicinal materials including Ginseng Radix et Rhizoma, Ophiopogon Radix, Schisandra chinensis Fructus, Erigerontis Herba, were firstly summarized respectively. Then the pharmacokinetics studies, quality control, and pharmacological properties of SSCPs were all reviewed. The active compounds, pharmacokinetics characterizes, quality control markers, the effects and mechanisms of pharmacology of the different dosage forms of SSCPs were summarized. Furthermore, the research deficiencies of SSCPs and an innovative research paradigm for Chinese materia medica (CMM) formula were proposed.

CONCLUSIONS

SMS, as a famous CMM formula, has great values in drug research and in clinical treatment especially for cardiocerebrovascular diseases. This article firstly make a comprehensive and systematic review on SMS.

Cloning and characterization of thermophilic endoglucanase and its application in the transformation of ginsenosides

A novel endoglucanase (BcelFp) was identified from Fervidobaterium pennivorans DSM9078 which had biotransformation activity for protopanaxadiol (PPD)-type ginsenosides. Sequence analysis of BcelFp revealed that it could be classified into glycoside hydrolase family 5 (GH5). The gene encoding a 323-amino acid protein was cloned and expressed in Escherichia coli. The recombinant enzyme was purified, and its molecular weight was approximate 37 kDa. The recombinant BcelFp exhibited an optimal activity at 95 oC and pH 5.5 and showed high thermostability. The endoglucanase had high selectivity for cleaving the outer glucose moiety at the C3 carbon of ginsenoside Rb1, Rb2, Rc and Rd, which produced stronger pharmacologically active gypenoside XVII (GypXVII), Compound O (CO), Compound Mc1 (CMc1) and F2, respectively. The Km values for Rb1, Rb2, Rc and Rd were 3.66 ± 0.04 µM, 4.02 ± 0.12 µM, 5.95 ± 0.03 µM, 0.67 ± 0.006 µM, respectively. The kcat/Km value of BcelFp for ginsenoside Rd was 27.91 mM-1s-1, which was much higher than that of the previously enzymes. This study was the first report of the highly efficient and selective transformation of GypXVII, CO, CMc1 and F2 from Rb1, Rb2, Rc and Rd by a GH5-family thermophilic endoglucanase.

Production of Minor Ginsenoside CK from Major Ginsenosides by Biotransformation and Its Advances in Targeted Delivery to Tumor Tissues Using Nanoformulations

For over 2000 years, ginseng (roots of Panax ginseng C.A. Meyer) has been used as a traditional herbal medicine. Ginsenosides are bioactive compounds present in ginseng responsible for the pharmacological effects and curing various acute diseases as well as chronic diseases including cardiovascular disease, cancer and diabetes. Structurally, ginsenosides consist of a hydrophobic aglycone moiety fused with one to four hydrophilic glycoside moieties. Based on the position of sugar units and their abundance, ginsenosides are classified into major and minor ginsenosides. Despite the great potential of ginsenosides, major ginsenosides are poorly absorbed in the blood circulation, resulting in poor bioavailability. Interestingly, owing to their small molecular weight, minor ginsenosides exhibit good permeability across cell membranes and bioavailability. However, extremely small quantities of minor ginsenosides extracted from ginseng plants cannot fulfill the requirement of scientific and clinical studies. Therefore, the production of minor ginsenosides in mass production is a topic of interest. In addition, their poor solubility and lack of targetability to tumor tissues limits their application in cancer therapy. In this review, various methods used for the transformation of major ginsenosides to minor ginsenoside compound K (CK) are summarized. For the production of CK, various transformation methods apply to major ginsenosides. The challenges present in these transformations and future research directions for producing bulk quantities of minor ginsenosides are discussed. Furthermore, attention is also paid to the utilization of nanoformulation technology to improve the bioavailability of minor ginsenoside CK.

Differential Metabolic Profiles of Ginsenosides in Artificial Gastric Juice Using ultra-high-pressure Liquid Chromatography Coupled with Linear ion trap-Orbitrap Mass Spectrometry

Ginsenosides have poor bioavailability of oral administration and undergo rapid biologic transformation in the complex gastrointestinal environment. Most studies on the metabolism of ginsenosides has focused on gut bacteria, yet gastric juice remains as a non-negligible factor. Metabolic profiles of ginsenoside monomers formed in artificial gastric juice were separately investigated and qualitatively identified by UHPLC-LTQ-Orbitrap MSⁿ . A common pattern of their metabolic pathways was established, showing that ginsenosides were transformed via deglycosylation, hydration and dehydration pathways. Two major structure types, PPTs and PPDs, basically shared similar transformation pathways and yielded deglycosylated, hydrated and dehydrated products. Fragmentation patterns of major ginsenosides were also discussed. Consequently, gastric juice, as the primary link in ginsenoside metabolism and as important as the intestinal flora, produces considerable amount of degraded ginsenosides, providing a partial explanation for the low bioavailabilities of primary ginsenosides.

Increased Production of Ginsenoside Compound K by Optimizing the Feeding of American Ginseng Extract during Fermentation by Aspergillus tubingensis

The ginsenoside compound K (C-K) is widely used in traditional medicines, nutritional supplements, and cosmetics owing to its diverse pharmacological activities. Although many studies on C-K production have been conducted, fermentation is reported to produce C-K with low concentration and productivity. In the present study, addition of an inducer and optimization of the carbon and nitrogen sources in the medium were performed using response surface methodology to increase the C-K production via fermentation by Aspergillus tubingensis, a generally recognized as safe fungus. The optimized inducer and carbon and nitrogen sources were 2 g/l rice straw, 10 g/l sucrose, and 10 g/l soy protein concentrate, respectively, and they resulted in a 3.1-fold increase in the concentration and productivity of C-K (0.22 g/l and 1.52 mg/l/h, respectively) compared to those used before optimization without inducer (0.071 g/l and 0.49 mg/l/h, respectively). The feeding methods of American ginseng extract (AGE), including feeding timing, feeding concentration, and feeding frequency, were also optimized. Under the optimized conditions, A. tubingensis produced 3.96 mM (2.47 g/l) C-K at 144 h by feeding two times with 8 g/l AGE at 48 and 60 h, with a productivity of 17.1 mg/l/h. The concentration and productivity of C-K after optimization of feeding methods were 11-fold higher than those before the optimization (0.22 g/l and 1.52 mg/l/h, respectively). Thus, the optimization for the feeding methods of ginseng extract is an efficient strategy to increase C-K production. To our knowledge, this is the highest reported C-K concentration and productivity via fermentation reported so far.

Biotransformation, Pharmacokinetics, and Pharmacological Activities of Ginsenoside Rd Against Multiple Diseases

Panax ginseng C.A. Mey. has a history of more than 4000 years and is widely used in Asian countries. Modern pharmacological studies have proved that ginsenosides and their compounds have a variety of significant biological activities on specific diseases, including neurodegenerative diseases, certain types of cancer, gastrointestinal disease, and metabolic diseases, in which most of the interest has focused on ginsenoside Rd. The evidentiary basis showed that ginsenoside Rd ameliorates ischemic stroke, nerve injury, cancer, and other diseases involved in apoptosis, inflammation, oxidative stress, mitochondrial damage, and autophagy. In this review, we summarized available reports on the molecular biological mechanisms of ginsenoside Rd in neurological diseases, cancer, metabolic diseases, and other diseases. We also discussed the main biotransformation pathways of ginsenoside Rd obtained by fermentation.

Progress in research of glycoside hydrolases in the intestine

Glycoside hydrolases are a class of enzymes that hydrolyze glycosides and play an important role in the metabolic transformation of glycosides in the intestine, but the number of glycoside hydrolases encoded and expressed in the body is limited, and most glycoside hydrolases are produced from intestinal bacteria genes. Gut microbiota and the secreted glycoside hydrolases participate in the deglycosylation of glycosides and improve their bioavailability. In this paper, we review the definition and types of glucoside hydrolases, their sources from the gut microbiota, and transformation of glycosides by the gut microbiota. We also discuss the relationship between the gut microbiota, glucoside hydrolases, and glucoside deglycosylation transformation products, with an aim to provide a reference for efficient production of enzymes and glycoside conversion products, and mining of new drug resources.

Molecular Cloning and Functional Characterization of a β-Glucosidase Gene to Produce Platycodin D in Platycodon grandiflorus

Platycodin D (PD) is a deglycosylated triterpene saponin with much higher pharmacological activity than glycosylated platycoside E (PE). Extensive studies in vitro showed that the transformation of platycoside E to platycodin D can be achieved using β-glucosidase extracted from several bacteria. However, whether similar enzymes in Platycodon grandiflorus could convert platycoside E to platycodin D, as well as the molecular mechanism underlying the deglycosylation process of platycodon E, remain unclear. Here, we identified a β-glucosidase in P. grandiflorus from our previous RNA-seq analysis, with a full-length cDNA of 1,488 bp encoding 495 amino acids. Bioinformatics and phylogenetic analyses showed that β-glucosidases in P. grandiflorus have high homology with other plant β-glucosidases. Subcellular localization showed that there is no subcellular preference for its encoding gene. β-glucosidase was successfully expressed as 6 × His-tagged fusion protein in Escherichia coli BL21 (DE3). Western blot analysis yielded a recombinant protein of approximately 68 kDa. In vitro enzymatic reactions determined that β-glucosidase was functional and could convert PE to PD. RT-qPCR analysis showed that the expression level of β-glucosidase was higher at night than during the day, with the highest expression level between 9:00 and 12:00 at night. Analysis of the promoter sequence showed many light-responsive cis-acting elements, suggesting that the light might regulate the gene. The results will contribute to the further study of the biosynthesis and metabolism regulation of triterpenoid saponins in P. grandiflorus.

Production of Deglucose-Apiose-Xylosylated Platycosides from Glycosylated Platycosides by Crude Enzyme from Aspergillus tubingensis

Platycosides, Platycodi radix (Platycodon grandiflorus root) saponins, are used as food supplements and exert diverse pharmacological activities. Deglycosylation of saponins enhances their biological efficacy, and deglycosylated platycosides are produced mainly through enzymatic hydrolysis. However, the types of available deglycosylated platycosides remain limited because of a lack of hydrolyzing enzymes that can act on specific glycosides in glycosylated platycosides. In this study, a crude enzyme from Aspergillus tubingensis converted platycoside E (PE) and polygalacin D₃ (PGD3) into deglucose-apiose-xylosylated (deGAX)-platycodin D (PD) and deGAX-polygalacin D (PGD), respectively. The products were identified through LC/MS analysis by specifically hydrolyzing all glucose residues at C-3, and apiose and xylose residues at C-28 of platycoside. The hydrolytic activity of the crude enzyme obtained after the cultivation of the fungus using citrus pectin and corn steep solid as carbon and nitrogen sources, respectively, in culture medium was increased compared with those using other carbon and nitrogen sources. The crude enzyme from A. tubingensis was the most effective in producing deGAX platycoside at pH 5.0 and 60°C. The crude enzyme produced 0.32 mg/ml deGAX-PD and 0.34 mg/ml deGAX-PGD from 1 mg/ml PE and 1 mg/ml PGD3 (at pH 5.0 and 60°C) for 12 and 10 h, with productivities of 32.0 and 42.5 mg/l/h and molar yields of 62.1 and 59.6%, respectively. To the best of our knowledge, this is the first study to produce deGAX platycosides from glycosylated platycosides.

Ginsenoside-Mc1 reduces cerebral ischemia-reperfusion injury in hyperlipidemia through mitochondrial improvement and attenuation of oxidative/endoplasmic reticulum stress

The neuroprotective effect of ginsenoside-Mc1 (GMc1) in hyperlipidemic rats in the setting of cerebral ischemiareperfusion injury (I/RI), as well as the role of mitochondrial ATP-sensitive potassium (mitoKATP) channels and oxidative/ endoplasmic reticulum (ER) stress, was investigated. Hyperlipidemia (8 weeks) was induced by a high-fat diet in Sprague Dawley rats. GMc1 (10 mg/kg, i.p.) was given to hyperlipidemic rats daily for one month before I/RI. Rat brains were subjected to 2 h of local ischemia followed by 24 h reperfusion. The cerebral infarcted injury was measured by triphenyltetrazolium chloride staining and the levels of oxidative stress indicators were detected by ELISA and spectrophotometry. A fluorometric technique was employed to evaluate mitochondrial function. Western blotting was used to detect changes in the expression of ER stress proteins. GMc1 reduced cerebral infarct volume in hyperlipidemic rats in comparison to untreated ones (P<0.01). GMc1 reduced cerebral infarct volume in hyperlipidemic rats as compared to untreated rats (P<0.01). GMc1 significantly decreased mitochondrial membrane depolarization, mitochondrial reactive oxygen species (mitoROS) and malondialdehyde levels (P<0.01), while increasing the activity of superoxide dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GPx) (P<0.001). GMc1 administration reduced the expression of ER stress markers, including phosphorylated (p)-endoplasmic reticulum kinase (PERK), p-eukaryotic translation initiation factor 2 subunit 1 (elF2?), and C/EBP homologous protein (CHOP). Inhibition of mitoKATP channels with hydroxydecanoate significantly eliminated the protective impacts of GMc1 in hyperlipidemic rats subjected to cerebral I/RI. The neuroprotective effect of GMc1 preconditioning was remarkably improved by increasing mitoKATP channel activity and decreasing oxidative and ER stress levels in hyperlipidemic rats, implying that this compound could be an appropriate candidate for reducing cerebral I/RI in comorbidities.

Ginseng extract and ginsenosides improve neurological function and promote antioxidant effects in rats with spinal cord injury: A meta-analysis and systematic review

Spinal cord injury (SCI) is defined as damage to the spinal cord that temporarily or permanently changes its function. There is no definite treatment established for neurological complete injury patients. This study investigated the effect of ginseng extract and ginsenosides on neurological recovery and antioxidant efficacies in rat models following SCI and explore the appropriate dosage. Searches were done on PubMed, Embase, and Chinese databases, and animal studies matches the inclusion criteria were selected. Pair-wise meta-analysis and subgroup analysis were performed. Ten studies were included, and the overall methodological qualities were low quality. The result showed ginseng extract and ginsenosides significantly improve neurological function, through the Basso, Beattie, and Bresnahan (BBB) locomotor rating scale (pooled MD = 4.40; 95% CI = 3.92 to 4.88; p < 0.00001), significantly decrease malondialdehyde (MDA) (n = 290; pooled MD = −2.19; 95% CI = −3.16 to −1.22; p < 0.0001) and increase superoxide dismutase (SOD) levels (n = 290; pooled MD = 2.14; 95% CI = 1.45 to 2.83; p < 0.00001). Both low (<25 mg/kg) and high dosage (≥25 mg/kg) showed significant improvement in the motor function recovery in SCI rats. Collectively, this review suggests ginseng extract and ginsenosides has a protective effect on SCI, with good safety and a clear mechanism of action and may be suitable for future clinical trials and applications.

Enhanced biotransformation of the minor ginsenosides in red ginseng extract by Penicillium decumbens β-glucosidase

Compound K (C-K) and Rh2, which are present at low levels in ginseng and ginseng extracts, have higher intestinal absorption rates than other ginsenosides. Here, we attempted to convert ginsenoside Rb1 to C-K using a β-glucosidase from Penicillium decumbens. Ten commercially available enzymes were screened to identify enzymes that can convert ginsenoside Rb1 to C-K, resulting in the selection of a P. decumbens-derived β-glucosidase. β-Glucosidase showed maximum activity at pH 4.0 and 60 °C; its substrate specificity for ginsenoside Rb1 was investigated. The main glucoside-hydrolyzing pathways were as follows: ginsenoside Rb1 or Rd → gypenoside XVII → F2 → C-K and ginsenoside Rg3 → Rh2. The P. decumbens-derived β-glucosidase was used to generate C-K and Rh2 using protopanaxadiol-type ginsenosides as substrates. Additionally, to apply this enzyme to the commercialized red ginseng extract products, the contents of C-K and Rh2 in the total ginsenosides significantly (p < 0.05) increased up to 36-fold and 8.9-fold, respectively, higher than prior to subjecting to biotransformation. To the best of our knowledge, this is the first report of the dual biotransformation of C-K and Rh2 by a food-grade commercial enzyme. This study demonstrates that the use of a specific β-glucosidase may increase C-K and Rh2 contents in the ginseng extract through a simple biotransformation process and, thus, enhance its health benefits.

Improved production of deglucosylated platycodin D from saponins from balloon flower leaf by a food-grade enzyme using high hydrostatic pressure

Platycosides, saponins contained in balloon flower, which have been used as food health supplements for respiratory diseases, have diverse pharmacological effects. Platycosides exhibit better pharmacological activity by hydrolyzing their own sugars. However, to date, there have been no studies on the production of deglucosylated platycodin D suitable for food applications. In this study, Pluszyme 2000P, which was derived from Aspergillus niger, a food-grade microorganism, was used to completely convert platycoside E into deglucosylated platycodin D. For an efficient and economical production of deglucosylated platycodin D, the productivity was improved approximately 2.4 times by application of high hydrostatic pressure and the discarded balloon flower leaf was used as a substrate. As a result, deglucosylated platycodin D was produced with the highest concentration (3.49 mg/mL) and productivity (581.7 mg/L/h) reported so far. Our results contribute to functional saponin production and the related food industries.

Production of minor ginsenosides by combining Stereum hirsutum and cellulase

Minor ginsenosides (MGs) (include ginsenoside F2, Compound K, PPT, etc), which are generally not produced by ginseng plants naturally, are obtained by deglycosylation of major ginsenosides. However, the conventional processes used to produce deglycosylated ginsenosides focus on the use of intestinal microorganisms for transformation. In this study, an edible and medicinal mushroom Stereum hirsutum JE0512 was screened from 161 β-glucosidase-producing soil microorganisms sourced from wild ginseng using the plate coloration method. Furthermore, JE0512 was used for the production of CK from ginseng extracts (GE) in solid-state fermentation (SSF) using 20 g corn bran as substrate, 4 g GE, and 20% inoculation volume, and the results showed that the highest CK content was 29.13 mg/g. After combining S. hirsutum JE0512 with cellulase (Aspergillus niger), the MGs (F2, CK, and PPT) content increased from 1.66 to 130.79 mg/g in the final products. Our results indicate that the Stereum genus has the potential to biotransform GE into CK and the combination of S. hirsutum JE0512 and cellulase could pave the way for the production of MGs from GE.

Pharmacological activities of ginsenoside Rg5 (Review)

Ginseng, a perennial plant belonging to genus Panax, has been widely used in traditional herbal medicine in East Asia and North America. Ginsenosides are the most important pharmacological component of ginseng. Variabilities in attached positions, inner and outer residues and types of sugar moieties may be associated with the specific pharmacological activities of each ginsenoside. Ginsenoside Rg5 (Rg5) is a minor ginsenoside synthesized during ginseng steaming treatment that exhibits superior pharmaceutical activity compared with major ginsenosides. With high safety and various biological functions, Rg5 may act as a potential therapeutic candidate for diverse diseases. To date, there have been no systematic studies on the activity of Rg5. Therefore, in this review, all available literature was reviewed and discussed to facilitate further research on Rg5.

Phytochemistry of ginsenosides: Recent advancements and emerging roles

Ginsenosides, a group of tetracyclic saponins, accounts for the nutraceutical and pharmaceutical relevance of the ginseng (Panax sp.) herb. Owing to the associated therapeutic potential of ginsenosides, their demand has been increased significantly in the last two decades. However, a slow growth cycle, low seed production, and long generation time of ginseng have created a gap between the demand and supply of ginsenosides. The biosynthesis of ginsenosides involves an intricate network of pathways with multiple oxidation and glycosylation reactions. However, the exact functions of some of the associated genes/proteins are still not completely deciphered. Moreover, ginsenoside estimation and extraction using analytical techniques are not feasible with high efficiency. The present review is a step forward in recapitulating the comprehensive aspects of ginsenosides including their distribution, structural diversity, biotransformation, and functional attributes in both plants and animals including humans. Moreover, ginsenoside biosynthesis in the potential plant sources and their metabolism in the human body along with major regulators and stimulators affecting ginsenoside biosynthesis have also been discussed. Furthermore, this review consolidates biotechnological interventions to enhance the biosynthesis of ginsenosides in their potential sources and advancements in the development of synthetic biosystems for efficient ginsenoside biosynthesis to meet their rising industrial demands.

Pharmacological Efficacy of Ginseng against Respiratory Tract Infections

Respiratory tract infections are underestimated, as they are mild and generally not incapacitating. In clinical medicine, however, these infections are considered a prevalent problem. By 2030, the third most comprehensive reason for death worldwide will be chronic obstructive pulmonary disease (COPD), according to the World Health Organization. The current arsenal of anti-inflammatory drugs shows little or no benefits against COPD. For thousands of years, herbal drugs have been used to cure numerous illnesses; they exhibit promising results and enhance physical performance. Ginseng is one such herbal medicine, known to alleviate pro-inflammatory chemokines and cytokines (IL-2, IL-4, IFN-γ, TNF-α, IL-5, IL-6, IL-8) formed by macrophages and epithelial cells. Furthermore, the mechanisms of action of ginsenoside are still not fully understood. Various clinical trials of ginseng have exhibited a reduction of repeated colds and the flu. In this review, ginseng’s structural features, the pathogenicity of microbial infections, and the immunomodulatory, antiviral, and anti-bacterial effects of ginseng were discussed. The focus was on the latest animal studies and human clinical trials that corroborate ginseng’s role as a therapy for treating respiratory tract infections. The article concluded with future directions and significant challenges. This review would be a valuable addition to the knowledge base for researchers in understanding the promising role of ginseng in treating respiratory tract infections. Further analysis needs to be re-focused on clinical trials to study ginseng’s efficacy and safety in treating pathogenic infections and in determining ginseng-drug interactions.

Improved Bioactivity of 3-O-β-D-Glucopyranosyl Platycosides in Biotransformed Platycodon grandiflorum Root Extract by Pectinase from Aspergillus aculeatus

Platycodon grandiflorum (balloon flower) root (Platycodi radix, PR) is used as a health supplement owing to its beneficial bioactive properties. In the present study, the anti-inflammatory, antioxidant, and whitening effects of deglycosylated platycosides (saponins) from PR biotransformed by pectinase from Aspergillus aculeatus were investigated. The bioactivities of the platycosides improved when the number of sugar moieties attached to the aglycone platycosides was decreased. The deglycosylated saponins exhibited higher lipoxygenase inhibitory activities (anti-inflammatory activities) than the precursor platycosides and the anti-inflammatory compound baicalein. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity of the pectinase-treated PR extract was higher than that of the non-treated PR extract. The trolox-equivalent antioxidant capacity (TEAC) assay showed improved values as the saponins were hydrolyzed. The tyrosinase inhibitory activities (whitening effects) of deglycosylated platycosides were higher than those of the precursor platycosides. Furthermore, 3-O-β-D-glucopyranosyl platycosides showed higher anti-inflammatory, antioxidant, and whitening activities than their precursor glycosylated platycosides. Therefore, 3-O-β-D-glucopyranosyl platycosides may improve the beneficial effects of nutritional supplements and cosmetic products.

Production of Bioactive Deapiosylated Platycosides from Glycosylated Platycosides in Balloon Flower Root Using the Crude Enzyme from the Food-Available Fungus Rhizopus oryzae

Extract from balloon flower root (Platycodi radix) containing platycosides as saponins is a beneficial food additive and is used for their savory taste and the alleviation of respiratory diseases. Deglycosylated platycosides show greater pharmacological effects than glycosylated platycosides. However, there are no reports on the conversion of glycosylated platycosides into deapiosylated platycosides. In this study, we showed that the crude enzyme from Rhizopus oryzae, a generally recognized as safe (GRAS) fungus isolated from meju (fermented soybean brick), completely converted glycosylated platycosides in Platycodi radix extract into deapiosylated platycosides: deapiosylated platycodin D (deapi-PD), deapiosylated platycodin A (deapi-PA), deapiosylated polygalacin D (deapi-PGD), and deapiosylated platyconic acid A (deapi-PCA). Among these, deapi-PA and deapi-PCA were first identified using liquid chromatography/mass spectrometry. The anti-inflammatory and antioxidant effects of deapiosylated platycosides were greater than those of the precursor glycosylated platycosides. These deapiosylated platycosides could improve the properties of functional food additives.

Biotransformation of ginsenoside Rc to Rd by endophytic bacterium Bacillus sp. G9y isolated from Panax quinquefolius

To isolate endophytic bacterium with the ability to specifically convert ginsenoside Rc from Panax quinquefolius. An endophytic bacterium G9y was isolated from Panax quinquefolius and indentified as Bacillus sp. based on 16s rDNA gene sequence. Ginsenoside Rc was effectively converted to Rd by G9y, which was confirmed by thin-layer chromatography and high performance liquid chromatography (HPLC) analysis. The biotransformation conditions were further optimized as follows: inoculum amount 5%, converting temperature 45 °C, medium beef extract peptone broth at pH of 7, and the time of Rc addition was 4 h after bacterium G9y growth, under which ginsenoside Rc was completely converted to Rd by bacterium G9y within 25 h after inoculation. A strain of G9y with the ability to convert ginsenoside Rc into Rd was screened from endophytic bacteria isolated from P. quinquefolius. The results provide a new microbial resource for preparing ginsenoside Rd via biotransformation, and explore a pathway for Rc utilization, which has great potential application value.

Ginsenosides for cardiovascular diseases; update on pre-clinical and clinical evidence, pharmacological effects and the mechanisms of action

Cardiovascular disease (CVD) remains the major cause of death worldwide, accounting for almost 31% of the global mortality annually. Several preclinical studies have indicated that ginseng and the major bioactive ingredient (ginsenosides) can modulate several CVDs through diverse mechanisms. However, there is paucity in the translation of such experiments into clinical arena for cardiovascular ailments due to lack of conclusive specific pathways through which these activities are initiated and lack of larger, long-term well-structured clinical trials. Therefore, this review elaborates on current pharmacological effects of ginseng and ginsenosides in the cardiovascular system and provides some insights into the safety, toxicity, and synergistic effects in human trials. The review concludes that before ginseng, ginsenosides and their preparations could be utilized in the clinical treatment of CVDs, there should be more preclinical studies in larger animals (like the guinea pig, rabbit, dog, and monkey) to find the specific dosages, address the toxicity, safety and synergistic effects with other conventional drugs. This could lead to the initiation of large-scale, long-term well-structured randomized, and placebo-controlled clinical trials to test whether treatment is effective for a longer period and test the efficacy against other conventional therapies.

Highly regioselective biotransformation of ginsenoside Rg1 to 25-OH derivatives of 20(S/R)-Rh1 by Cordyceps Sinensis

25-OH ginsenosides are potent and rare prodrugs in natural sources. However current strategies for such modification always end up in undesirable side products and unsatisfied yield that hinders them from further applications. Herein, ginsenoside Rg1 was thoroughly converted into 20(S/R)-Rh1 and 25-OH-20(S/R)-Rh1 by Cordyceps Sinensis in an optimum medium. The chemical correctness of either 25-OH-20(S/R)-Rh1 epimers was validated by LC-IT-TOF-MSn and ¹³C NMR spectrometry. The biocatalytic pathway was established as Rg1 → 20(S/R)-Rh1 → 25-OH-20(S/R)-Rh1. The molar bioconversion rate for total 25-OH-20(S/R)-Rh1 was calculated to be 82.5%, of which S-configuration accounted for 43.2% while R-configuration 39.3%. These two 25-OH derivatives are direct hydration products from 20(S/R)-Rh1 without other side metabolites, suggesting this is a highly regioselective process. In conclusion, this biocatalytic system could be harnessed to facilitate the preparation of diversified 25-OH ginsenosides with high yields of the target compound and simple chemical background in the reaction mixture.

Ginsenoside Mc1 improves liver steatosis and insulin resistance by attenuating ER stress

ETHNOPHARMACOLOGICAL RELEVANCE

Ginsenoside, a major pharmacologically active ingredient in ginseng, has been known to exhibit beneficial properties such as antioxidant and anti-inflammatory effects. Ginsenoside compound Mc1 is one of the newly identified de-glycosylated ginsenosides. Endoplasmic reticulum (ER) stress has implicated in the development of non-alcoholic fatty liver disease (NAFLD) through apoptosis and lipid accumulation.

AIM OF THE STUDY

We aimed to examine the protective effects of Mc1 treatment on ER stress-induced cell death and impaired insulin signaling in HepG2 human hepatoblastoma cells and ER stress-induced liver steatosis and insulin resistance in a diet-induced obesity (DIO) mouse model.

MATERIALS AND METHODS

HepG2 cells were treated with palmitate and Mc1 to evaluate the effects of Mc1 on ER stress-induced damage. C57BL/6 mice were fed with a high-fat diet (HFD) for 4 weeks and received an intraperitoneal injection of either vehicle or Mc1 (10 mg/kg/day). The control mice were fed with a chow diet and injected with vehicle for the same period. ER stress, cell death, and degree of steatosis were evaluated in the liver tissues of mice. The effect of Mc1 treatment on glucose metabolism was also determined.

RESULTS

Mc1 co-treatment reduced the palmitate-induced ER stress and death of HepG2 cells. The palmitate-induced insulin resistance improved after Mc1 co-treatment. Consistent with the in vitro data, chronic Mc1 supplementation reduced ER stress and apoptotic damage in the liver of obese mice. Mc1 treatment ameliorated glucose intolerance and insulin resistance through the suppression of c-Jun N-terminal kinase (JNK) phosphorylation. In addition, Mc1 treatment reduced obesity-induced lipogenesis and prevented fat accumulation in the liver of DIO mice.

CONCLUSIONS

Mc1 exerted protective effects against ER stress-induced apoptotic damage, insulin resistance and lipogenesis in palmitate-treated hepatocytes and in the liver of DIO mice. Therefore, Mc1 supplementation could be a potential therapeutic strategy to prevent NAFLD in patients with obesity and insulin resistance.

Advances in the Production of Minor Ginsenosides Using Microorganisms and Their Enzymes

Abstract Minor ginsenodes are of great interest due to their diverse pharmacological activities such as their anti-cancer, anti-diabetic, neuroprotective, immunomodulator, and anti-inflammatory effects. The miniscule amount of minor ginsenosides in ginseng plants has driven the development of their mass production methods. Among the various production methods for minor ginsenosides, the utilization of microorganisms and their enzymes are considered as highly specific, safe, and environmentally friendly. In this review, various minor ginsenosides production strategies, namely utilizing microorganisms and recombinant microbial enzymes, for biotransforming major ginsenosides into minor ginsenoside, as well as constructing synthetic minor ginsenosides production pathways in yeast cell factories, are described and discussed. Furthermore, the present challenges and future research direction for producing minor ginsenosides using those approaches are discussed.

Biotransformation of Glycosylated Saponins in Balloon Flower Root Extract into 3-O-β-D-Glucopyranosyl Platycosides by Deglycosylation of Pectinase from Aspergillus aculeatus

Platycodon grandiflorum root (Platycodi radix) saponins, platycosides, have been used as health supplements and food items for the treatment of respiratory disorders and pulmonary diseases. Deglycosylated saponins have been known to exert stronger biological effects than their glycosylated forms. In the present study, glycosylated platycosides in Platycodi radix extract were biotransformed into deglycosylated 3-O-β-D-glucopyranosyl platycosides, including 3-O-β-Dglucopyranosyl platycodigenin, 3-O-β-D-glucopyranosyl polygalacic acid, and 3-O-β-Dglucopyranosyl platyconic acid, by pectinase from Aspergillus aculeatus. This is the first report on the quantitative enzymatic production of 3-O-β-D-glucopyranosyl platycosides. The chemical structures of 3-O-β-D-glucopyranosyl platycosides were identified with LC/MS. Moreover, the biotransformation pathways of the three types of platycosides in Platycodi radix into 3-O-β-Dglucopyranosyl platycosides were established.