Metals/bisulfite system involved generation of 24-sulfonic-25-ene ginsenoside Rg1, a potential quality control marker for sulfur-fumigated ginseng

Ginseng is a most popular health-promoting food with ginsenosides as its main bioactive ingredients. Illegal sulfur-fumigation causes ginsenosides convert to toxic sulfur-containing derivatives, and reduced the efficacy/safety of ginseng. 24-sulfo-25-ene ginsenoside Rg1 (25-ene SRg1), one of the sulfur-containing derivatives, is a potential quality control marker of fumigated ginseng, but with low accessibility owing to its unknown generation mechanism. In this study, metals/bisulfite system involved generation mechanism was investigated and verified. The generation of 25-ene SRg1 in sulfur-fumigated ginseng is that SO2, formed during sulfur-fumigation, reacted with water and ionized into HSO3-. On the one hand, under the metals/bisulfite system, HSO3- generates HSO5- and free radicals which converted ginsenoside Rg1 to 24,25-epoxide Rg1; on the other hand, as a nucleophilic group, HSO3- reacted with 24,25-epoxide Rg1 and further dehydrated to 25-ene SRg1. This study provided a technical support for the promotion of 25-ene SRg1 as the characteristic quality control marker of sulfur-fumigated ginseng.

Selection and application of aptamers for p-hydroxybenzyl hydrogen sulfite after Gastrodia elata Bl. fumigated with sulfur

Gastrodia elata Bl. is a widely used traditional Chinese medicine known for its medicinal properties. However, during the drying process, G. elata is often fumigated with sulfur to prevent corrosion and improve its appearance. Sulfur-fumigation can result in a reduction in the effective components of the herb and can also be hazardous to human health due to the remaining sulfur dioxide. Sulfur-fumigation of G. elata poses a significant challenge to both end-users and researchers. The detection of p-hydroxybenzyl hydrogen sulfite (p-HS) is a useful tool in determining whether G. elata has been fumigated with sulfur. Unfortunately, the current method for detecting p-HS is costly and requires sophisticated instruments. Therefore, there is a need to develop a more cost-effective and user-friendly method for the detection of p-HS. This study utilized the Capture-SELEX technique to screen high-affinity aptamers for p-HS, which were subsequently characterized by isothermal titration calorimetry (ITC). An aptamer sequence (seq 6) with a high affinity of Kd = 26.5 μM was obtained following 8 rounds of selection against p-HS. With the aptamer serving as the recognition element and gold nanoparticles as the colorimetric indicator, a simple and efficient colorimetric sensor was developed for the specific detection of p-HS. This detection method exhibited a limit of detection of 1 μg/ml, while the p-HS recoveries demonstrated a range of between 88.5 % and 105 % for samples of G. elata obtained in the market. In summary, the aptamer exhibited a high affinity for p-HS, and the sensor developed through the use of a colloidal gold detector based on nucleic acid aptamer can be utilized for rapid detection of sulfur-fumigated G. elata. With these findings, this research paper provides valuable scientific insights and highlights significant potential for future studies in this area.

Impact of sulfur-fumigation on carbohydrate components of Atractylodis Macrocephalae Rhizoma

Atractylodis Macrocephalae Rhizoma (AMR) is one of commonly used medicinal and edible herbs in China. It is often sulfur-fumigated during post-harvest processing. Carbohydrates are important active components of AMR. However, it is unknown whether sulfur-fumigation would induce changes on carbohydrates. Here, carbohydrates including polysaccharides, oligosaccharides and free monosaccharides were comprehensively analyzed to characterize the quality changes of sulfur-fumigated AMR. Determination of both homemade sulfur-fumigated AMR samples and commercial samples from market revealed that sulfur-fumigation did not affect molecular weight distribution of polysaccharides, but altered polysaccharides content and its ratios of constituent monosaccharides, especially glucose (Glc) and fructose (Fru), as well as the contents of oligosaccharides DP2-10 and free monosaccharide Fru. Moreover, the variations enhanced with the increasing of residual SO₂ content. The potential transformation mechanisms could be due to the hydrolysis of polysaccharides. The research outcomes could provide a chemical basis for the safety and efficacy evaluations of sulfur-fumigated AMR.

Effects and contributory factors of sulfur-fumigation on the efficacy and safety of medicinal herbs evaluated by meta-analysis

ETHNOPHARMACOLOGICAL RELEVANCE

Sulfur-fumigation undoubtedly alters the chemical and metabolic profiles, but controversially affects the efficacy and safety of medicinal herbs.

AIM OF THE STUDY

To comprehensively evaluate the effects of sulfur-fumigation on the efficacy and safety of medicinal herbs using a meta-analysis approach and further investigate the potential contributory factors.

MATERIALS AND METHODS

Literatures were retrieved on PubMed, Web of Science, Embase, China National Knowledge Infrastructure, Chinese VIP Information and Wanfang, and the outcomes involved activities and toxicities were extracted using standard data extraction forms. The effects of sulfur-fumigation on the efficacy and safety of medicinal herbs were evaluated by meta-analysis approaches.

RESULTS

A total of sixteen studies were included in this study. Sulfur-fumigation reduced the efficacies of medicinal herbs with immune activity [thymus index (SMD = -1.81; P < 0.00001); spleen index (SMD = -1.11; P < 0.0001)], anti-oxidative activity [MDA (SMD = 2.60; P = 0.04); SOD (SMD = -2.21; P < 0.00001)], analgesic activity [heat tolerate time (SMD = -2.51; P = 0.001); writhing time (SMD = 0.36; P = 0.006)], anti-platelet aggregation activity (SMD = -1.84; P = 0.001), and anti-inflammatory activity [ear swelling degree (SMD = 0.47; P = 0.006)]. The reductions might be ascribed to sulfur-fumigation significantly reduced the contents of active ingredients in medicinal herbs, leading to dramatic decrease in the absorption of these ingredients and their metabolites in vivo. Furthermore, sulfur-fumigation induced the toxicities of medicinal herbs, mainly on hepatotoxicity, which might due to fumigation-induced residues of sulfur dioxide and heavy metal, and generations of sulfur-containing derivatives and toxic metabolites. Besides, administrated with sulfur-fumigated medicinal herbs with high sulfur ratio and/or higher dosage showed more significant toxicity.

CONCLUSION

Sulfur-fumigation reduced the efficacy and safety of medicinal herbs, indicating sulfur-fumigation might not a feasible approach to process medicinal herbs. However, with obvious limitations, much more rigorous designed-trials are still needed to confirm the conclusion.

Effects of sulfur-fumigated ginseng on the global quality of Si-Jun-Zi decoction, a traditional ginseng-containing multi-herb prescription, evaluated by metabolomics and glycomics strategies

Si-Jun-Zi decoction (SJZD) with ginseng as the principal medicinal herb is a traditional Chinese Medicine multi-herb prescription that commonly employed to treat colorectal cancer etc. Previous studies showed that nearly half of the commercial ginseng was sulfur-fumigated, one of the postharvest processing methods that commonly causes sulfur-dioxide (SO₂) residue and chemical composition transformation in medical herbs. In this study, the effect of sulfur-fumigated ginseng on global quality of SJZD was evaluated by UPLC-QTOF-MS/MS based metabolomics and multiple chromatographic techniques based glycomics strategies. For non-saccharides components, sulfur-fumigated ginseng led to the emergence of sulfur-containing derivatives and alteration of saponins and flavonoids in SJZD. For saccharide components, sulfur-fumigated ginseng decreased the total contents and molecular weights of polysaccharides, changed the monosaccharide composition of polysaccharides, and increased the contents of oligosaccharides and free monosaccharides of SJZD. The alterations of SJZD were aggravated with the sulfur-fumigated content of ginseng. Those phenomena might be attributed to 1) sulfur-fumigation caused the generation of sulfur-containing derivatives in ginseng, which further transferred to SJZD, and 2) sulfur-fumigation caused the residue of SO₂ in ginseng, which reduced the pH value and further changed the dissolution of saponins and flavonoids and accelerated the degradation of the polysaccharides to oligosaccharides and/or monosaccharides in SJZD. Furthermore, although storage reduced the SO₂ residue in sulfur-fumigated ginseng, it couldn't recover the alterations of chemical profiles in SJZD. In conclusion, sulfur-fumigated ginseng altered the global quality of SJZD, which promoted that extra attention must be paid during the application of herbal formulas that containing sulfur-fumigated herbs.

Effect of sulfur-fumigation process on ginseng: Metabolism and absorption evidences

ETHNOPHARMACOLOGICAL RELEVANCE

Sulfur-fumigation has been developed to prevent insects and molds during post-harvest handling of Panax ginseng C.A. Mey (ginseng) in the near decades. Our previous study indicated sulfur-fumigation could transform ginsenosides, the active components of ginseng, into sulfur-containing derivatives (SFCDs), the artifacts with unknown toxicity. However, whether the biotransformation could be occurred and absorption characteristics between ginsenosides and SFCDs are still needed to further investigate.

AIM OF THE STUDY

To evaluate the effect of sulfur-fumigation process on ginseng through comparing the metabolic profile and absorption characteristics between ginsenoside Rg1, Re and their SFCDs.

MATERIALS AND METHODS

Intestinal microflora and liver S9 fraction were utilized to compare the metabolic profile, and single-pass intestinal perfusion and Caco-2 cell models were applied to compare the absorption characteristics, between Rg1, Re and their SFCDs.

RESULTS

Rg1 and Re were metabolized to 7 none sulfur-containing metabolites, while their SFCDs were metabolized to 18 sulfur-containing metabolites. The intestinal absorption and transport of Rg1 and Re were much greater than their SFCDs. Besides, the uptakes of Rg1 and Re were transport-dependent, but their SFCDs were non-transport-dependent.

CONCLUSION

Ginsenosides and their SFCDs could not be bio-transformed with each other and their absorption characteristics were quite different, which suggested that sulfur-fumigation is not a feasible post-harvest process of ginseng.

A new approach for identification of medicinal almonds by fourier transform infrared spectroscopy and systematic clustering of characteristic peaks

Medicinal almonds have been used for over 2 000 years and its clinical efficacy includes relieving cough and asthma. The domestic market in China is flooded with different kinds of dried almonds, such as bitter almond (Armeniacae Semen Amarum, AAS), sweet almond (Armeniacae Semen Dulce, ADS), salted almond (Armeniacae Semen Salsa, ASS), and their sulfur-fumigating products (Armeniacae Semen Sulphur Fumabat, ASFS). Wide varieties of almonds may lead to uncertain efficacy, aberrant quality, and even increased safety risk. However, the authentication method for medicinal almonds has not been reported, although imposters may lead to ineffective medical response. In the present study, Fourier transform infrared spectroscopy (FTIR) and the 2-dimensional infrared (2D-IR) spectroscopy were used to identify different almonds, which were extracted with different solvents including water, methanol, ethanol, chloroform and ethyl acetate, respectively. A new simple FTIR method was developed in the present study. According to the gradient solvent polarity, a new 2D IR method was first developed, and the commodities of almonds in China were analyzed by using the FTIR spectroscopy supported by hierarchical clustering of characteristic peaks. Moreover, 5-hydroxymethyl-2-furfural could be used as a detection index and control target in the quality control of medicinal almonds.

Rapid discrimination of raw and sulfur-fumigated Smilax glabra based on chemical profiles by UHPLC-QTOF-MS/MS coupled with multivariate statistical analysis

Smilax glabra (SG) is commonly used as a traditional edible herb in eastern Asia. Recently, sulfur-fumigation has been frequently used in order to obtain better color and a longer storage lifetime. However, the chemical alterations caused by this process remain unknown. The aim of this research was to explore potential chemical differences between non-fumigated and sulfur-fumigated SG samples. A novel approach was developed by using ultra-high-performance liquid chromatography-quadrupole/time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) with principal component analysis (PCA) and orthogonal partial squared discriminant analysis (OPLS-DA). Fifty-eight compounds were unambiguously characterized or tentatively identified in the chemical profiles for the first time. Six newly generated sulfur-containing compounds, namely glucosyringic acid sulfate, 5-O-caffeoylshikimic acid sulfite, 3-O-caffeoylshikimic acid sulfite, 5-O-caffeoylshikimic acid sulfate, 3-O-caffeoylshikimic acid sulfate and astilbin sulfate, were screened out to be the most characteristic markers for distinguishing non-fumigated and sulfur-fumigated SG. This newly proposed approach can not only be applied for exploring chemical markers but can also be used to investigate the chemical transformation mechanism associated with sulfur for other edible herbs.

Effects of sulfur-fumigation on the pharmacokinetics, metabolites and analgesic activity of Radix Paeoniae Alba

ETHNOPHARMACOLOGICAL RELEVANCE

Radix Paeoniae Alba (Baishao, BS), one of the most commonly used traditional Chinese medicinal herbs, has many pharmacological effects including analgesic activity. Previous studies found that sulfur-fumigation, a post-harvest handling process developed to prevent mold contamination of medicinal herbs, altered the quality of BS. However, whether sulfur-fumigation affects the pharmacokinetics, safety and efficacy of BS warrants further investigation.

AIM OF THE STUDY

To evaluate the feasibility of sulfur-fumigation as a post-harvest handling process of BS from the viewpoints of pharmacokinetics, safety and efficacy.

MATERIALS AND METHODS

The pharmacokinetic behaviors of four active components of BS and one characteristic component of sulfur-fumigated BS (S-BS) were evaluated by high performance liquid chromatography triple quadrupole mass spectrometry (HPLC-TQ-MS/MS). The safety was investigated using ultra high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS/MS) based metabolomics approach after intragastric (i.g.) administration of non-fumigated BS (N-BS) and S-BS in rats. The analgesic efficacy was compared using hot-plate test in mice, after i.g. administration of N-BS and S-BS, at both high and low dosages.

RESULTS

Systemic exposures of paeoniflorin and oxypaeoniflorin, two analgesic components of BS, were significantly decreased in the S-BS treated group compared to the N-BS treated group, while paeoniflorin sulfonate, one of the sulfur-containing derivatives of S-BS, was detected in all time-points of S-BS treated group with the area under the plasma concentration-time curve (AUC_0-t) and the maximum plasma concentration (C_max) as high as 7077.06 ± 2232.97ng/mL*h and 1641.42 ± 634.79ng/mL respectively, which indicated that sulfur-fumigation altered the pharmacokinetic behaviors of BS. Besides, paeoniflorin sulfonate and its four metabolites with ambiguous toxicities, as well as one endogenous metabolite p-cresol glucuronide, the biomarker of disordered homeostasis of intestinal bacteria and bile acid, were identified as the characteristic metabolites in S-BS administered rats, suggesting that sulfur-fumigation reduced the safety of BS. Furthermore, the analgesic effects at both low and high dosages were decreased in different extent when compared to N-BS administered groups, indicating that sulfur-fumigation weakened the efficacy of BS.

CONCLUSION

Sulfur-fumigation altered the pharmacokinetics, as well as reduced the safety and efficacy of BS, suggesting that sulfur-fumigation is not recommended for post-harvest handling of BS.

A practical protocol for comprehensive evaluation of sulfur-fumigation of Gastrodia Rhizoma using metabolome and health risk assessment analysis

Gastrodia Rhizoma is one of the most heavily sulfur-fumigated edible and medical herbs in the marketplace. We developed a practical protocol using an ultra-performance liquid chromatography coupled with quadrupole time-of-flight-MS^E (UPLC/QTOF-MS^E)-based metabolome and health risk assessment model to identify characteristic sulfur-fumigated markers, dissect chemical transformation mechanisms, and control the quality of sulfur-fumigated Gastrodia Rhizoma. Two sulfur-containing p-hydroxybenzyl products, one sulfur-containing disaccharide, one glycolipid, and two phospholipids were selected and identified as markers based on multivariate statistical analysis. In particular, the sulfur-containing markers p-hydroxybenzyl hydrogen sulfite and trace p-mercaptobenzyl hydrogen sulfate were positively correlated with the active major phenolics. Moreover, a practical index the time of the minimum content was useful for evaluating the extent of the sulfur-fumigation under different weight ratios of the sulfur to herbal materials (1:20, 1:40, and 1:80). Ultimately, the 1:40 ratio within 1h of sulfur-fumigation was considered as safe and efficient for herb quality preservation under the maximum residue limit of 750mg/kg. This study shows that the practical protocol-based discriminated markers and practical limits can be applied to quality assurance of sulfur-fumigation and non-fumigation Gastrodia Rhizoma and other edible or medical materials.

HPLC-TOF-MS and HPLC-MS/MS combined with multivariate analysis for the characterization and discrimination of phenolic profiles in nonfumigated and sulfur-fumigated rhubarb

Sulfur fumigation has recently been used during the postharvest handling of rhubarb to reduce the drying duration and control pests. However, a few reports question the effect of sulfur fumigation on the bioactive components of rhubarb, which is crucial for the quality evaluation of the herbal medicine. The bottleneck limiting the study comes from the complex compounds that exist in herb samples with diverse structural features, wide concentration range and the difficulty to obtain all the reference standards. In this study, an integrated strategy based on the highly effective separation and analysis by liquid chromatography coupled with diode-array detection and time-of-flight/triple-quadruple tandem mass spectrometry combined with multivariate analysis was established. 68 phenolic compounds that exist in nonfumigated and sulfur-fumigated herb samples of rhubarb were tentatively assigned based on their retention behavior, UV spectra, accurate molecular weight, and mass spectral fragments. Qualitative and semiquantitative comparison revealed a serious reduction of the majority of phenolic compounds in sulfur-fumigated rhubarb. Furthermore, multivariate analysis was applied to holistically discriminate nonfumigated from sulfur-fumigated rhubarb and explore the characteristic chemical markers. The established approach was specific and rapid for characterizing and screening sulfur-fumigated rhubarb among commercial samples and could be applied for the quality assessment of other sulfur-fumigated herbs.

Sulfur dioxide residue in sulfur-fumigated edible herbs: The fewer, the safer?

The residual content of sulfur dioxide is frequently regarded as the exclusive indicator in the safety evaluation of sulfur-fumigated edible herbs. To examine the feasibility of such assessment criteria, here the variations in residual sulfur dioxide content during sulfur-fumigation and the potential mechanisms involved were investigated, using Angelicae Sinensis Radix (ASR) as a model herb. The residual sulfur dioxide content and ten major bioactive components in sulfur-fumigated ASR samples were dynamically examined at 13 successive time points within 72 h sulfur-fumigation. The relationship between the content variation tendency of sulfur dioxide and the ten chemicals was discussed. The results suggested that sulfur dioxide-involved chemical transformation of the original components in ASR might cause large consumption of residual sulfur dioxide during sulfur-fumigation. It implies that without considering the induced chemical transformation of bioactive components, the residual sulfur dioxide content alone might be inadequate to comprehensively evaluate the safety of sulfur-fumigated herbs.

The sulfur-fumigation reduces chemical composition and biological properties of Angelicae Sinensis Radix

Angelica Sinensis Radix (roots of Angelica sinensis; ASR) is a popular herbal supplement in China for promoting blood circulation. Today, sulfur-fumigation is commonly used to treat ASR as a means of pest control; however, the studies of sulfur-fumigation on the safety and efficacy of ASR are very limited. Here, we elucidated the destructive roles of sulfur-fumigation on ASR by chemical and biological assessments. After sulfur-fumigation, the chemicals in ASR were significantly lost. The biological activities of anti-platelet aggregation, induction of NO production and estrogenic properties were compared between the water extracts of non-fumigated and sulfur-fumigated ASR. In all cases, the sulfur-fumigation significantly reduced the biological properties of ASR. In addition, application of water extract deriving from sulfur-fumigated ASR showed toxicity to cultured MCF-7 cells. In order to ensure the safety and to achieve the best therapeutic effect, it is recommended that sulfur-fumigation is an unacceptable approach for processing herbal materials.