Residues of 18 organochlorine pesticides in 30 traditional Chinese medicines

Research on Chinese medicinal materials cultivation: A bibliometric and visual analysis

Chinese medicinal materials (CMMs) are important strategic resource in China. The cultivation process of medicinal plants is the key link which directly affect the quality and efficacy. The literatures of CMMs cultivation were acquired from China National Knowledge Infrastructure (CNKI) database and State Intellectual Property Office (SIPO) patent database for the years between 2001 and 2021. All the articles found were subjected to bibliometric analysis. The development trends and key topics were analyzed and visualized by VOSviewer and CiteSpace software. The results indicate that ecological planting, under-forest economy, intercropping patterns and industrialization production are the research hotspots in this field; cultivation technology and nutritional fertilization technology are the main areas addressed in recent years. Therefore, the high-quality and sustainable development of CMMs cultivation should be examined in terms of theoretical approaches, technical innovation, multi-cooperation, and intellectual property protection.

Toxicological effects, residue levels and risks of endocrine-disrupting chemicals in Chinese medicine: a review

Traditional Chinese medicine (TCM) that is used worldwide possesses the satisfactory function of disease prevention, treatment and health care, and this natural medicine seems to be favored due to its low side effects. Endocrine disrupting chemicals (EDCs), which exist in all aspects of our lives, may interfere with the synthesis, action and metabolism of human sex steroid hormones, resulting in the development and fertility problems as well as obesity and the disturbance of energy homeostasis. From planting to processing, TCM may be polluted by various EDCs. Many studies pay attention to this problem, but there are still few reviews on the residues and toxicity risks of EDCs in TCM. In this paper, researches related to EDCs in TCM were screened. The possible contamination sources of TCM from planting to processing and its toxic effects were introduced. Moreover, the residues of metals, pesticides and other EDCs in TCM as well as the health risks of human exposure to EDCs through ingestion of TCM materials were reviewed.

Organochlorine pesticide residue in Chinese herbal medicine

Over ten-year routine inspection results on organochlorine pesticide (OCP) residue were summarized, OCPs residues, including BHC isomers (α, β, γ, and δ-BHC), DDT analogs (p,p'-DDD, p,p'-DDE, o,p'-DDT, and p,p'-DDT), and pentachloronitrobenzene (PCNB) and its metabolites (pentachloroaniline and methyl pentachlorophenyl sulfide (MPCPS)), in 1,665 samples for 37 types of Chinese herbal medicine (CHM) using the QuEChERS method coupled with the GC-ECD. Based on the maximal residue levels for OCPs set by Asian pharmacopeias, PCNB contamination in Ginseng radix as well as the total DDT and PCNB contamination in Panacis quinquefolii radix are of concern. OCP residues in different parts of Panax ginseng were also compared. The total BHC residue in leaf and fibrous root, as well as the total DDT and PCNB residue in all parts, exceeded MRL of 0.1 mg/kg. Overall, this study provided meaningful results about OCP residue in CHM for pharmaceutical industries and consumers.

Dissipation Behavior of Three Fungicides during the Industrial Processing of Paeoniae Radix Alba and Associated Processing Factors

Before being administered as medicinal products, Chinese herbal medicines (CHMs) must be processed and decocted for human consumption. While the presence of pesticide residues in CHMs is a major concern, pesticide dissipation behavior during CHM processing has rarely been reported. In this study, the dissipation of three pesticide residues in the CHM Paeoniae Radix Alba (PRA) was investigated during each step of industrial processing. The boiling process was found to significantly reduce pesticide residues (61–89%), and the peeling process also contributed to pesticide degradation (29–68%). The high temperature (60 °C) during the drying process led to further pesticide degradation. The processing factors of all three pesticides after each processing step were less than one, and the processing factors for the overall process were lower than 0.027, indicating that industrial processing clearly reduced the amount of pesticide residues (97.3–99.4%). The findings provide guidance for the safe use of fungicides in CHMs and can help establish maximum residue limits for PRA to reduce human exposure to pesticides.

The potential of three different PCR-related approaches for the authentication of mixtures of herbal substances and finished herbal medicinal products

BACKGROUND

Herbal substances and preparations thereof play an important role in healthcare systems worldwide. Due to the variety of these products regarding origin, composition and processing procedures, appropriate methodologies for quality assessment need to be considered. A majority of herbal substances is administered as multicomponent mixtures, especially in the field of Traditional Chinese Medicine and ayurvedic medicine, but also in finished medicinal products. Quality assessment of complex mixtures of herbal substances with conventional methods is challenging. Thus, emphasis of the present work was directed on the development of complementary methods to elucidate the composition of mixtures of herbal substances and finished herbal medicinal products.

HYPOTHESIS/PURPOSE

An indispensable prerequisite for the safe and effective use of herbal medicines is the unequivocal authentication of the medicinal plants used therein. In this context, we investigated the potential of three different PCR-related methods in the characterization and authentication of herbal substances.

METHODS

A multiplex PCR assay and a quantitative PCR (qPCR) assay were established to analyze defined mixtures of the herbal substances Quercus cortex, Juglandis folium, Aristolochiae herba, Matricariae flos and Salviae miltiorrhizae radix et rhizoma and a finished herbal medicinal product. Furthermore, a standard cloning approach using universal primers targeting the ITS region was established in order to allow the investigation of herbal mixtures with unknown content.

RESULTS

The cloning approach had some limitations regarding the detection/recovery of the components in defined mixtures of herbal substances, but the complementary use of two sets of universal primer pairs increased the detection of components out of the mixture. While the multiplex PCR did not retrace all components in the defined mixtures of herbal substances, the established qPCR resulted in simultaneous and specific detection of the five target sequences in all defined mixtures.

CONCLUSION

These data indicate that for authentication purposes, complementary PCR-related methods are highly recommendable for the analysis of herbal mixtures in parallel.

Simultaneous determination of organochlorine and pyrethriod pesticide residues in the Chinese patent medicines by gas chromatography-tandem mass spectrometry

A simple, sensitive, reliable method was developed for the simultaneous determination of organochlorine and pyrethriod pesticide residues in Chinese patent medicines Six ingredient rehmannia pills and Xiaoyao pills. These pesticides were extracted by ethyl acetate. The extraction time and volume of ethyl acetate were optimized. Cleanup of extracts was performed with dispersive-solid phase extraction using graphitized carbon black as the sorbent. The determination of pesticides in the final extracts was carried out by gas chromatography-tandem mass spectrometry in multiple reaction monitoring mode (GC-MS/MS, MRM). The linearity of the calibration curves is good in matrix-matched standard and yields the coefficients of determination (R²) ≥0.99 for all of the target analytes. Under optimized conditions, the average recoveries (five replicates) for most pesticides range from 75.5% to 114.6%, and RSDs are less than 10.0%. The LODs of 18 pesticides in Six ingredient rehmannia pill and Xiaoyao pills are in the range of 0.01-8.82 μg kg^-1. The developed method meets the requirements of pesticide residue analysis and could be effectively used for routine analysis of the organochlorine and pyrethriod pesticide residues in Six ingredient rehmannia pills and Xiaoyao pills.

Biodegradation of pentachloronitrobenzene by Cupriavidus sp. YNS-85 and its potential for remediation of contaminated soils

Pentachloronitrobenzene (PCNB) is a toxic chlorinated nitroaromatic compound. However, only a few bacteria have been reported to be able to utilize PCNB. In the present study, one pentachloronitrobenzene (PCNB)-degrading bacterium, Cupriavidus sp. YNS-85, was isolated from a contaminated Panax notoginseng plantation. The strain co-metabolized 200 mg L^-1 PCNB in aqueous solution with a removal rate of 73.8% after 5 days. The bacterium also degraded PCNB effectively under acid conditions (pH 4-6) and showed resistance to toxic trace elements (arsenic, copper, and cadmium). Its ability to utilize proposed PCNB intermediates as sole carbon sources was also confirmed. The soil microcosm experiment further demonstrated that bacterial bioaugmentation enhanced the removal of PCNB (37.8%) from soil and the accumulation of pentachloroaniline (89.3%) after 30 days. Soil enzyme activity and microbial community functional diversity were positively influenced after bioremediation. These findings indicate that Cupriavidus sp. YNS-85 may be a suitable inoculant for in situ bioremediation of PCNB-polluted sites, especially those with acid soils co-contaminated with heavy metal(loid)s.

Chemical and Physical Methods to Analyze a Multicomponent Traditional Chinese Herbal Prescription Using LC-MS/MS, Electron Microscope, and Congo Red Staining

This study develops several chemical and physical methods to evaluate the quality of a traditional Chinese formulation, Jia-Wei-Xiao-Yao-San. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with electrospray ionization was used to measure the herbal biomarkers of saikosaponin A, saikosaponin D, ferulic acid, and paeoniflorin from this herbal formula. A scanning electron microscope (SEM) and light microscopy photographs with Congo red staining were used to identify the cellulose fibers if raw herbal powder had been added to the herbal pharmaceutical product. Moreover, water solubility and crude fiber content examination were used to inspect for potential herbal additives to the herbal pharmaceutical products. The results demonstrate that the contents of the herbal ingredients of saikosaponin A, saikosaponin D, ferulic acid, and paeoniflorin were around 0.351 ± 0.017, 0.136 ± 0.010, 0.140 ± 0.005, and 2.281 ± 0.406 mg/g, respectively, for this herbal pharmaceutical product. The physical examination data demonstrate that the raw herbal powder had rough, irregular, lumpy, filamentous, and elongated shapes, as well as strong Congo red staining. In addition, water solubility and crude fiber content were not consistent in the herbal pharmaceutical products.

Comparison of different sample pre-treatments for multi-residue analysis of organochlorine and pyrethroid pesticides in chrysanthemum by gas chromatography with electron capture detection

The widespread use of insecticides in Chinese herbal medicines has created a compelling need for the development of a multiresidue analytical method to help assure herbs safety. The operating variables affecting the performance of the multiresidue analysis of 34 organochlorine and 12 pyrethroid pesticides in chrysanthemum, a widely used kind of Chinese herbal medicines, were evaluated. Three different extraction solvents including n-hexane and its mixtures with acetone and petroleum ether were compared, and n-hexane was found to be an appropriate option. A combination of gel permeation chromatography and SPE was selected as the optimum cleanup, in comparison with dispersive SPE, or the two former methods alone. The determination of the 46 pesticide residues in the spiked chrysanthemum samples was performed by GC with electron capture detection. The average recoveries ranged from 71.3 to 102.6% with RSDs of 1.4-15.7% for all of the pesticides. The LOQs were in the range of 0.0015-0.2 mg/kg, while the LODs were between 0.0005 and 0.1 mg/kg. The satisfactory accuracy, and precision, in combination with a good separation and few interferences, have demonstrated the strong potential of this technique for its application in chrysanthemum analysis.

Quality of herbal medicines: challenges and solutions

The popularity of herbal medicines has risen worldwide. This increase in usage renders safety issues important. Many adverse events of herbal medicines can be attributed to the poor quality of the raw materials or the finished products. Different types of herbal medicines are associated with different problems. Quality issues of herbal medicines can be classified into two categories: external and internal. In this review, external issues including contamination (e.g. toxic metals, pesticides residues and microbes), adulteration and misidentification are detailed. Complexity and non-uniformity of the ingredients in herbal medicines are the internal issues affecting the quality of herbal medicines. Solutions to the raised problems are discussed. The rigorous implementation of Good Agricultural and Collection Practices (GACP) and Good Manufacturing Practices (GMP) would undoubtedly reduce the risk of external issues. Through the use of modern analytical methods and pharmaceutical techniques, previously unsolved internal issues have become solvable. Standard herbal products can be manufactured from the standard herbal extracts.

Heavy metal and pesticide content in commonly prescribed individual raw Chinese Herbal Medicines

Heavy metal and pesticide contamination has previously been reported in Chinese Herbal Medicines (CHMs), in some cases at potentially toxic levels. This study was conducted to determine general patterns and toxicological significance of heavy metal and pesticide contamination in a broad sample of raw CHMs. Three-hundred-thirty-four samples representing 126 species of CHMs were collected throughout China and examined for arsenic, cadmium, chromium, lead, and mercury. Of the total, 294 samples representing 112 species were also tested for 162 pesticides. At least 1 metal was detected in all 334 samples (100%) and 115 samples (34%) had detectable levels of all metals. Forty-two different pesticides were detected in 108 samples (36.7%), with 1 to 9 pesticides per sample. Contaminant levels were compared to toxicological reference values in the context of different exposure scenarios. According to a likely scenario of CHM consumption, only 3 samples (1%) with heavy metals and 14 samples (5%) with pesticides were found with concentrations that could contribute to elevated background levels of contaminant exposure. According to the most conservative scenario of CHM consumption, 231 samples (69%) with heavy metals and 81 samples (28%) with pesticides had contaminants that could contribute to elevated levels of exposure. Wild collected plants had higher contaminant levels than cultivated samples. Cadmium, chromium, lead, and chlorpyrifos contamination showed weak correlations with geographic location. Based on our assumptions of the likely mode of consumption of raw CHMs, the vast majority (95%) of the 334 samples in this study contained levels of heavy metals or pesticides that would be of negligible concern. However, given the number of samples with detectable contaminants and the range between the more likely and more conservative scenarios of contaminant exposure, more research and monitoring of heavy metals (especially cadmium and chromium) and pesticide residues (especially chlorpyrifos) in raw CHMs are advised.

Analysis of pesticide residues using the Quick Easy Cheap Effective Rugged and Safe (QuEChERS) pesticide multiresidue method in traditional Chinese medicine by gas chromatography with electron capture detection

The Quick Easy Cheap Effective Rugged and Safe multiresidue method (QuEChERS) has been validated for the extraction of 15 organochlorine pesticides (OCPs) in completely different matrices of traditional Chinese medicine (TCM). The method employed a rapid, simple and cost-effective procedure. The spiking levels for the recovery experiments were 0.1, 0.5 and 2.0 mg kg(-1). Mean recoveries mostly ranged between 76.0% and 114.0% (96.0% on average), and relative standard deviations (RSD) were generally below 10% (4.72% on average). Based on these results, the methodology has been proven to be highly efficient and robust and thus suitable for monitoring the MRL compliance of a wide range of commodity. The contamination status of 15 OCPs on 80 different TCMs marketed in China, and a total of 400 samples were also performed using a previously validated method. 15 OCPs were benzene hexachloride (BHC, including α-BHC, β-BHC, γ-BHC, δ-BHC), hexachlorobenzene, heptachlor, heptachlor epoxide, aldrin, p, p'-DDE, p, p'-DDD, o, p'-DDT, p, p'-DDT, mirex, endrin, dieldrin. This study indicates that the proposed method is useful for analyzing OCPs in TCM.

Analysis of contaminant polycyclic aromatic hydrocarbons in tea products and crude drugs

Tea products and crude drugs were analyzed to determine levels of contamination with 15 polycyclic aromatic hydrocarbons (PAHs) using a new online automated method, consisting of in-tube solid-phase microextraction (SPME) coupled with high-performance liquid chromatography-fluorescence detection (HPLC-FLD). PAHs were separated within 15 min by HPLC using a Zorbax Eclipse PAH column with a water/acetonitrile gradient elution program as the mobile phase. The optimum in-tube SPME conditions were 20 draw/eject cycles of 40 µL of sample using a CP-Sil 19CB capillary column as an extraction device. Low- and high-molecular weight PAHs were extracted effectively onto the capillary coating from 5% and 30% methanol solutions, respectively. The extracted PAHs were readily desorbed from the capillary by passage of the mobile phase. Good linearity of the calibration curve (r > 0.9972) was obtained in the concentration range of 0.05-2.0 ng mL-1, and the detection limits (S/N = 3) of PAHs were 0.32-4.63 pg mL-1. Using the in-tube SPME/HPLC-FLD method, PAHs were detected at ng g-1 levels in the samples without interference peaks. Our results suggest that PAHs contamination in herbal products is widespread, and the proposed method may become a useful tool for monitoring PAH contamination and quality control in herbal products.

Simultaneous determination of organophosphorus and organonitrogen pesticides residues in Angelica sinensis

Gas chromatography with nitrogen phosphorus detector (GC-NPD) was applied to the simultaneous determination of 15 organophosphorus and 6 organonitrogen pesticides residues in Angelica sinensis. The pesticides were extracted by microwave-assisted extraction (MAE) and ultrasound-assisted extraction (UAE) techniques, respectively. The experimental variables were optimized through orthogonal array experimental design. Cleanup of extracts was performed with column chromatography using florisil and neutral aluminum as the sorbents. The determination of pesticides in the final extracts was carried out by GC-NPD. Under optimized conditions, the average recoveries obtained from MAE and UAE are in the range of 75.1-129% and 70.6-129%, respectively, and the relative standard deviations of MAE and UAE were 3.1-10.6% and 1.0-17.8%, respectively.

Contaminants of medicinal herbs and herbal products

Medicinal plants have a long history of use in therapy throughout the world and still make an important part of traditional medicine. Thus, medicinal plants and herbal products must be safe for the patient (consumer). This review addresses biological contaminants (microbes and other organisms) and chemical contaminants (mycotoxins, toxic elements such as heavy metals, and pesticide residues) as major common contaminants of medicinal herbs and herbal products. To prevent and screen for contamination and ensure safety and conformity to quality standards, medicinal herbs and herbal products should be included in appropriate regulatory framework.

Simple and reliable methods for the determination of sixteen marker components for quality control of Daochi pill by HPLC coupled with diode array detection

INTRODUCTION

Traditional Chinese medicine plays a very important role in the healthcare system of China and thus the quality control of medicinal herb products is of paramount concern.

OBJECTIVE

To establish a simple and effective high-performance liquid chromatography (HPLC) method to evaluate the quality of Daochi pill.

METHODOLOGY

Two HPLC methods were developed for the determination of 16 marker components in Daochi pills. In method A, the analytes were separated on a Lichrosorb C(18) column using a gradient elution of methanol and 1% aqueous phosphoric acid (pH 2.9, adjusted by triethylamine). In method B, the separation was achieved on an Agilent Eclipse Plus C(18) column using a gradient elution of methanol and 3% aqueous phosphoric acid (pH 2.0, adjusted by triethylamine) in a gradient elution mode.

RESULTS

Methods were linear over the range 0.27-500 microg/mL (r(2) >or= 0.9995). Accuracy, precision and repeatability were all within the required limits. The mean recoveries measured at three concentrations were higher than 95% with RSD <or= 4% for the targets.

CONCLUSION

The established methods are simple and can be used as tools for quality evaluation and control of this natural product.