Development of microwave-assisted extraction followed by headspace single-drop microextraction for fast determination of paeonol in traditional Chinese medicines

Tuning water chemistry for the recovery of greener products: pragmatic and sustainable approaches

The environmental impact and denaturing propensity of organic solvents in the extraction of plant bioactives pose great challenges in extraction systems. As a result, proactive consideration of procedures and evidence for tuning water properties for better recovery and positive influence on the green synthesis of products become pivotal. The conventional maceration approach takes a longer duration (1-72 h) for product recovery while percolation, distillation, and Soxhlet extractions take about 1 to 6 h. An intensified modern hydro-extraction process was identified for tuning water properties with an appreciable yield similar to organic solvents within 10-15 min. The percentage yield of tuned hydro-solvents achieved close to 90% recovery of active metabolites. The additional advantage of using tuned water over organic solvents is in the preservation of the bio-activities and forestalling the possibility of contamination of the bio-matrices during extractions with an organic solvent. This advantage is based on the fast extraction rate and selectivity of the tuned solvent when compared to the traditional approach. This review uniquely approaches the study of biometabolite recovery through insights from the chemistry of water under different extraction techniques for the very first time. Current challenges and prospects from the study are further presented.

Paeonol Ameliorates Abdominal Aortic Aneurysm Progression by the NF-κB Pathway

OBJECTIVE

Abdominal aortic aneurysm (AAA) is a chronic inflammatory disease characterized by localized progressive dilatation. Currently, paeonol has been shown to possess anti-inflammatory and protective cardiovascular properties. Our study aimed to investigate the potential influences of paeonol on AAA progression.

METHODS

Experimental AAAs were created in C57BL/6J mice by intra-aortic infusion of porcine pancreatic elastase, and then intragastrically administered paeonol (20 mg/kg/day) for 14 days. The effects of paeonol on experimental AAA were measured by ultrasound imaging, histopathology, and western blot analyses.

RESULTS

Paeonol treatment limited the enlargement of the aneurysmal diameter and alleviated the depletion of elastic fibers and vascular smooth muscle cells (VSMCs). Furthermore, the infiltration of CD68+ macrophages and CD8+ lymphocytes was obviously attenuated after paeonol administration, along with mural neoangiogenesis. Western blot results showed that paeonol inhibited the expression of matrix metalloproteinase (MMP) and the NF-κB pathway activation.

CONCLUSIONS

Paeonol might prevent experimental AAA progression by inhibiting the NF-κB pathway, which suggests that it is a potential drug for AAA.

Paeonol inhibits human lung cancer cell viability and metastasis in vitro via miR-126-5p/ZEB2 axis

Paeonol exerted an effect in lung cancer, but the underlying mechanism remained vague. In this research, we assessed the effects of Paeonol and microRNA (miR)-126-5p on the viability, migration, invasion, and epithelial-mesenchymal transition (EMT) of lung cancer cells. Lung cancer cells and BEAS-2B cells were treated with Paeonol, and viability was detected by 3-(4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay. The migration and invasion of lung cancer cells after treatment with Paeonol at 40 μg/mL or 80 μg/mL were detected by wound healing assay and Transwell assay, respectively. The effects of Paeonol on transforming growth factor-β1 (TGF-β1)-induced EMT and relative expressions of EMT-related proteins were determined using Western blot. The target gene of miR-126-5p and the binding sites between them were predicted by TargetScan, and confirmed using dual-luciferase reporter assay. Relative expressions of miR-126-5p, its target gene and EMT-related proteins were determined by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Rescue assay was performed to analyze the relation between Paeonol and miR-126-5p. Paeonol down-regulated cell viability and inhibited migration, invasion and TGF-β1-induced EMT while up-regulating miR-126-5p expression in lung cancer cells as the dose increased. However, miR-126-5p inhibitor could reverse the effect of Paeonol. ZEB2 was the target gene of miR-126-5p, and silencing ZEB2 expression reversed the effects of miR-126-5p downregulation. Paeonol also regulated the expression of ZEB2 in lung cancer cells, and this regulation depends on the regulation of miR-126-5p. Paeonol inhibits human lung cancer cell viability and metastasis via the miR-126-5p/ZEB2 axis, and could be adopted as a potential agent for lung cancer treatment.

Application of liquid-phase microextraction to the analysis of plant and herbal samples

INTRODUCTION

The analysis of plant and herbal samples is a challenging task for analytical chemists due to the complexity of the matrix combined with the low concentration of analytes. In recent years different liquid-phase microextraction (LPME) techniques coupled with a variety of analytical equipment have been developed for the determination of both organic and inorganic analytes.

OBJECTIVE

Over the past few years, the number of research papers in this field has shown a markedly growing tendency. Therefore, the purpose of this review paper is to summarise and critically evaluate research articles focused on the application of LPME techniques for the analysis of plant and herbal samples.

RESULTS

Due to the complex nature of the samples, the direct application of LPME techniques to the analysis of plants has not often been done. LPME techniques as well as their modalities have been commonly applied in combination with other pretreatment techniques, including a solid-liquid extraction technique supported by mechanical agitation or auxiliary energies for plant analysis. Applications and the most important parameters are summarised in the tables.

CONCLUSION

This review summarises the application of the LPME procedure and shows the major benefits of LPME, such as the low volume of solvents used, high enrichment factor, simplicity of operation and wide selection of applicable detection techniques. We can expect further development of microextraction analytical methods that focus on direct sample analysis with the application of green extraction solvents while fully automating procedures for the analysis of plant materials.

Cynanchum paniculatum (Bunge) Kitag. ex H. Hara: A review of its ethnopharmacology, phytochemistry and pharmacology

ETHNOPHARMACOLOGICAL RELEVANCE

Cynanchum paniculatum (Bunge) Kitag. ex H. Hara (C. paniculatum), is a broadly used traditional medicinal plant by East Asians. The roots and rhizomes of this herb were named 'Xu-Chang-Qing' since the Qin or Han Dynasty (B.C.221-220) in China. It is pungent and warm in nature and associated with the liver and stomach meridians. Moreover, the efficacy of this herb are dispelling wind, resolving dampness, relieving pain and itching. It is used for treating the onset of rheumatic arthralgia, stomachache, toothache, lumbago, soft tissue injury, rubella and eczema.

AIM OF THE STUDY

The purpose of this paper is to provide a systematic review about the botany, traditional uses, phytochemistry and pharmacology of C. paniculatum on the strength of the studies in the past two decades.

MATERIALS AND METHODS

A comprehensive search on previous literature was conducted on databases such as Web of Science, Pubmed, Sciencedirect, American Chemical Society (ACS), Google scholar and China national knowledge internet (CNKI). The search was based on the botany, traditional uses, phytochemistry and pharmacology of C. paniculatum. The key search words were 'Cynanchum paniculatum' and 'Radix Cynanchi Paniculati'. In addition, some published books were searched for more information on the herb.

RESULTS

Over 150 compounds have been isolated and identified from C. paniculatum, including C₂₁ steroids, volatile oils, carbohydrates and phenanthroindolizidine alkaloids. Extensive pharmacological activities of the extracts or compounds of C. paniculatum in vivo and in vitro were confirmed including anti-inflammatory, anti-nociceptive, sedative antiviral, antitumor, neuroprotective, treating snake bites, immunomodulatory, anti-radiation, vasodilatory, acaricidal potentials and anti-adipogenic activities.

CONCLUSIONS

In this paper, the botany, traditional uses, phytochemistry and pharmacology of C. paniculatum were reviewed. This herb has long been used as traditional medicine. It was reported with numerous chemical ingredients and various pharmacological activities with anti-inflammatory, antitumor, neuroprotection, etc. In the future, C. paniculatum still needs further study, such as identifying the active compounds, clarifying the pharmacological mechanisms, discussing quality and safety.

Extraction of Flavonoids From Natural Sources Using Modern Techniques

Flavonoids are one of the main groups of polyphenols found in natural products. Traditional flavonoid extraction techniques are being replaced by advanced techniques to reduce energy and solvent consumption, increase efficiency and selectivity, to meet increased market demand and environmental regulations. Advanced technologies, such as microwaves, ultrasound, pressurized liquids, supercritical fluids, and electric fields, are alternatives currently being used. These modern techniques are generally faster, more environmentally friendly, and with higher automation levels compared to conventional extraction techniques. This review will discuss the different methods available for flavonoid extraction from natural sources and the main parameters involved (temperature, solvent, sample quantity, extraction time, among others). Recent trends and their industrial importance are also discussed in detail, providing insight into their potential. Thus, this paper seeks to review the innovations of compound extraction techniques, presenting in each of them their advantages and disadvantages, trying to offer a broader scope in the understanding of flavonoid extraction from different plant matrices.

Cynanchum paniculatum and Its Major Active Constituents for Inflammatory-Related Diseases: A Review of Traditional Use, Multiple Pathway Modulations, and Clinical Applications

Cynanchum paniculatum Radix, known as Xuchangqing in Chinese, is commonly prescribed in Chinese Medicine (CM) for the treatment of various inflammatory diseases. The anti-inflammatory property of Cynanchum paniculatum can be traced from its wind-damp removing, collaterals' obstruction relieving, and toxins counteracting effects as folk medicine in CM. This paper systematically reviewed the research advancement of the pharmacological effects of Cynanchum paniculatum among a variety of human diseases, including diseases of the respiratory, circulatory, digestive, urogenital, hematopoietic, endocrine and metabolomic, neurological, skeletal, and rheumatological systems and malignant diseases. This review aims to link the long history of clinical applications of Cynanchum paniculatum in CM with recent biomedical investigations. The major bioactive chemical compositions of Cynanchum paniculatum and their associated action mechanism unveiled by biomedical investigations as well as the present clinical applications and future perspectives are discussed. The major focuses of this review are on the diverse mechanisms of Cynanchum paniculatum and the role of its active components in inflammatory diseases.

Paeonol attenuates isoflurane anesthesia-induced hippocampal neurotoxicity via modulation of JNK/ERK/P38MAPK pathway and regulates histone acetylation in neonatal rat

Objective: Volatile anesthetic such as isoflurane causes widespread neurodegeneration in the developing animal brains and also induces cognitive impairments. Paeonol is a plant-derived phenolic compound possessing numerous bioactive properties. The study investigates the neuroprotective effects of paeonol against isoflurane-induced neurodegeneration and cognitive disturbances in neonatal rats.Methods: Paeonol (50, 100, and 150 mg/kg body weight/day) was given orally to separate groups of neonatal rats from postnatal day 3 (P3) to P21 and were exposed to isoflurane (0.75%; 6 h) on P7.Results: Neuroapoptosis following isoflurane exposure was remarkably reduced by paeonol. Isoflurane-induced elevated cleaved caspase-3, Bad, and Bax expression, were down-regulated on paeonol administration. Paeonol significantly enhanced expression of antiapoptotic proteins (Bcl-2, Bcl-xL, xIAP, c-IAP-1, c-IAP-2, and survivin) and improved acetylation of HK39 and HK412. The expression of histone deacetylases (HDACs)-HDAC2 and HDAC-3 were down-regulated. Isoflurane-induced activation of JNK/p38MAPK signaling and suppressed ERK signaling and were effectively regulated by paeonol. General behavior and freezing responses of the rats were improved. Results of the Morris Water Maze tests revealed improved learning and memory retention on paeonol treatment.Conclusions: Paeonol effectively inhibited neuroapoptosis and improved isoflurane-induced cognitive dysfunctions via regulating histone acetylation and JNK/ERK1/2/p38MAPK signaling pathways.

Role of Paeonol in an Astrocyte Model of Parkinson's Disease

Background

Parkinson’s disease (PD) is characterized by a progressive degeneration of dopaminergic (DA) neurons in the substantia nigra pars compacta (SNc). Inflammation and neural degeneration are implicated in the pathogenesis of PD. Paeonol has been verified to attenuate inflammation.

Material/Methods

1-methyl-4-phenylpyridnium ion (MPP+, 100 μM) was used to induce the cell model of PD in primary cultured astrocytes. Astrocyte cell viability and apoptosis were determined by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay and flow cytometry (FCM), respectively. Protein levels of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthases (iNOS) in culture medium were tested by enzyme-linked immunosorbent (ELISA) assay. Protein levels of casapse-1, COX2, iNOS, B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), Bcl-2, and phosphorylated Jun N-terminal kinase (p-JNK)/phosphorylated extracellular signal-regulated kinase (p-ERK)/p-P38 were examined by Western blot.

Results

Pretreatment with paeonol remarkably rescued MPP+-induced cell viability reduction, up-regulation of cell apoptosis, caspase-1 activity, COX-2, iNOS, and Bax/Bcl-2 ratio in primary astrocytes. Furthermore, paeonol repressed MPP+ -induced elevation of p-JNK/p-ERK in primary cultured astrocytes.

Conclusions

The present study found that paeonol protected cells from apoptosis by repressing the activation of the JNK/ERK related signalling pathway induced by MPP+ in astrocytes. We propose that paeonol is a neuroprotective agent for the treatment of PD patients, with great promise in the future.

The Effects of Xiangqing Anodyne Spray on Treating Acute Soft-Tissue Injury Mainly Depend on Suppressing Activations of AKT and p38 Pathways

Objectives. In the present study we try to elucidate the mechanism of Xiangqing anodyne spray (XQAS) effects on acute soft-tissue injury (STI). Methods. Acute STI model was established by hammer blow in the rat hind leg muscle. Within 8 hours, instantly after modeling and per 2-hour interval repeated topical applications with or without XQAS, CP or IH ethanol extracts spray (CPS and IHS) were performed, respectively; muscle swelling rate and inflammation-related biochemical parameters, muscle histological observation, and mRNA and protein expression were then examined. Results. XQAS dose-dependently suppressed STI-caused muscle swelling, proinflammatory mediator productions, and oxidative stress as well as severe pathological changes in the injured muscle tissue. Moreover, CPS mainly by blocking p38 activation while IHS majorly by blocking AKT activation led to cytoplastic IκBα degradation with NF-κB p65 translocated into the nucleus. There are synergistic effects between CP and IH components in the XQAS on preventing from acute STI with suppressing IκBα degradation, NF-κB p65 translocation, and subsequent inflammation and oxidative stress-related abnormality. Conclusion. Marked effects of XQAS on treating acute STI are ascribed to strong anti-inflammatory and antioxidative actions with a reasonable combination of CP active components, blocking p38-NF-κB pathway activated, and IH active components, blocking AKT-NF-κB pathway activated.

Qualitative and Quantitative Analysis of Volatile Components of Zhengtian Pills Using Gas Chromatography Mass Spectrometry and Ultra-High Performance Liquid Chromatography

Zhengtian pills (ZTPs) are traditional Chinese medicine (TCM) which have been commonly used to treat headaches. Volatile components of ZTPs extracted by ethyl acetate with an ultrasonic method were analyzed by gas chromatography mass spectrometry (GC-MS). Twenty-two components were identified, accounting for 78.884% of the total components of volatile oil. The three main volatile components including protocatechuic acid, ferulic acid, and ligustilide were simultaneously determined using ultra-high performance liquid chromatography coupled with diode array detection (UHPLC-DAD). Baseline separation was achieved on an XB-C18 column with linear gradient elution of methanol-0.2% acetic acid aqueous solution. The UHPLC-DAD method provided good linearity (R (2) ≥ 0.9992), precision (RSD < 3%), accuracy (100.68-102.69%), and robustness. The UHPLC-DAD/GC-MS method was successfully utilized to analyze volatile components, protocatechuic acid, ferulic acid, and ligustilide, in 13 batches of ZTPs, which is suitable for discrimination and quality assessment of ZTPs.

Investigation of excited-state intramolecular proton transfer coupled charge transfer reaction of paeonol

An excited-state intramolecular proton transfer (ESIPT) coupled charge transfer reaction of paeonol was investigated both experimentally and theoretically. The ESIPT reaction of paeonol was predicted based on the large Stokes shift, which is observed in steady-state absorption and fluorescence spectra in an ethanol solution. The steady-state spectra in some solutions, such as methanol, ethanol, propanol, dichloromethane, and n-hexane, illustrate that the ESIPT reaction of paeonol has no dependence on the solvent properties. Therefore, the excited-state intermolecular proton transfer cannot be generated in protic solvents. Using the density functional theory and time-dependent density functional theory methods, we make a subsequent theoretical calculation that indicates that the ESIPT reaction of paeonol occurs through the intramolecular hydrogen bond O−H···O=C. The excited-state potential energy curve of paeonol indicates that the ESIPT reaction is a barrierless process, and the fluorescence emission of paeonol at 493 nm in the ethanol solution was assigned to the keto isomer fluorescence. Additionally, we also found an intramolecular charge transfer in the excited state by analysing the frontier molecular orbitals of paeonol.

A review on plant-based rutin extraction methods and its pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Rutin is a common dietary flavonoid that is widely consumed from plant-derived beverages and foods as traditional and folkloric medicine worldwide. Rutin is believed to exhibit significant pharmacological activities, including anti-oxidation, anti-inflammation, anti-diabetic, anti-adipogenic, neuroprotective and hormone therapy. Till date, over 130 registered therapeutic medicinal preparations are containing rutin in their formulations. This article aims to critically review the extraction methods for plant-based rutin and its pharmacological activities. This review provides comprehensive data on the performance of rutin extraction methods and the extent of its pharmacological activities using various in vitro and in vivo experimental models.

MATERIALS AND METHODS

Literatures including journals, patents, books and leaflets reporting on rutin from natural resources are systematically reviewed, particularly in the aspect of its extraction methods and biological activities. Factors affecting the efficiency of rutin extraction such as extraction temperature, duration and solvent to sample ratio are presented based on the findings of previous studies. The observed biological activities followed by clear explanation are also provided accordingly.

RESULTS

The biological activities of rutin varied largely dependent on the geographical and plant origins. The complexity of natural rutin has impeded the development of rutin derived drugs. The detail mechanism of rutin in human body after consumption is still unclear. Therefore, studies are intensively carried out both in vitro and in vivo for the better understanding of the underlying mechanism. The studies are not limited to the pharmacological properties, but also on the extraction methods of rutin. Many studies have focused on the optimization of extraction method to increase the extraction yield of rutin. Currently, the performances of modern extraction approaches have also been compared to the conventional heat reflux method as a benchmark.

CONCLUSION

There are various extraction methods for plant-based rutin ranging from conventional method up to the use of modern techniques such as ultrasound, mechanochemical, microwave, infrared and pressurized assisted methods. However, proper comparison between the methods is very difficult because of the variance in plant origin and extraction conditions. It is important to optimize the extraction method in order to produce high yield and acceptable purity of rutin with a reasonable cost. Even though rutin has been proven to be effective in numerous pharmacological activities, the dosage and toxicity of rutin for such activities are still unknown. Future research should relate the dosage and toxicity of rutin for the ethnobotanical claims based on the underlying mechanisms.

Headspace single-drop microextraction gas chromatography mass spectrometry for the analysis of volatile compounds from herba asari

A rapid headspace single-drop microextraction gas chromatography mass spectrometry (SDME-GC-MS) for the analysis of the volatile compounds in Herba Asari was developed in this study. The extraction solvent, extraction temperature and time, sample amount, and particle size were optimized. A mixed solvent of n-tridecane and butyl acetate (1 : 1) was finally used for the extraction with sample amount of 0.750 g and 100-mesh particle size at 70°C for 15 min. Under the determined conditions, the pound samples of Herba Asari were directly applied for the analysis. The result showed that SDME-GC-MS method was a simple, effective, and inexpensive way to measure the volatile compounds in Herba Asari and could be used for the analysis of volatile compounds in Chinese medicine.

Analysis of Rutin fromLespedeza virgata(Thunb.) DC. by Microwave-Assisted Extraction and Capillary Electrophoresis

A simple and rapid microwave-assisted extraction (MAE) technique was developed for the extraction of rutin fromLespedeza virgata(Thunb.) DC. The influence of four extraction variables on extraction of rutin was discussed. The optimum extraction conditions found were 75% aqueous ethanol, solvent volume to sample weight ratio at 90 : 1, extracting temperature at75°C, and extraction time for 15 min. A comparison was made among MAE, classical maceration, and ultrasonic-assisted extraction (UAE). Yields were determined by high-performance capillary electrophoresis (HPCE). The whole analysis process was completed in ten minutes. The needful volumes of sample and buffer are very little. Compared with maceration and ultrasonic extraction, MAE is a rapid method with higher yield and less solvent consumption.

Recent advances in liquid microextraction techniques coupled with MS for determination of small-molecule drugs in biological samples

Sample preparation is an important and necessary step in a measurement process for isolation and concentration of desired components from complex matrices. It is the most time-consuming and error-prone step in analytical methodology, greatly affecting quality and quantity of analytical data. During the past 15 years, solvent microextraction techniques have been introduced as alternatives to conventional sample preparation methods, such as liquid–liquid extraction and solid-phase extraction. These novel methodologies, which have proved to be extremely simple, low-cost and virtually solvent-free sample-preparation techniques provide a high degree of selectivity, sample cleanup and enrichment. The aim of the present review is to explore recent analytical applications of solvent microextraction techniques for quantification of drugs in biological samples, with particular focus on the methods involving MS as a detection system.

Optimization of microwave-assisted extraction for the characterization of olive leaf phenolic compounds by using HPLC-ESI-TOF-MS/IT-MS(2)

In the present work, a simple and rapid method for the extraction of phenolic compounds from olive leaves, using microwave-assisted extraction (MAE) technique, has been developed. The experimental variables that affect the MAE process, such as the solvent type and composition, microwave temperature, and extraction time, were optimized using a univariate method. The obtained extracts were analyzed by using high-performance liquid chromatography (HPLC) coupled to electrospray time-of-flight mass spectrometry (ESI-TOF-MS) and electrospray ion trap tandem mass spectrometry (ESI-IT-MS(2)) to prove the MAE extraction efficiency. The optimal MAE conditions were methanol:water (80:20, v/v) as extracting solvent, at a temperature equal to 80 °C for 6 min. Under these conditions, several phenolic compounds could be characterized by HPLC-ESI-MS/MS(2). As compared to the conventional method, MAE can be used as an alternative extraction method for the characterization of phenolic compounds from olive leaves due to its efficiency and speed.

Application of microwave-assisted extraction coupled with high-speed counter-current chromatography for separation and purification of dehydrocavidine from Corydalis saxicola Bunting

INTRODUCTION

Dehydrocavidine is a major component of Corydalis saxicola Bunting with sedative, analgesic, anticonvulsive and antibacterial activities. Conventional methods have disadvantages in extracting, separating and purifying dehydrocavidine from C. saxicola. Hence, an efficient method should be established.

OBJECTIVE

To develop a suitable preparative method in order to isolate dehydrocavidine from a complex C. saxicola extract by preparative HSCCC.

METHODOLOGY

The methanol extract of C. saxicola was prepared by optimised microwave-assisted extraction (MAE). The analytical HSCCC was used for the exploration of suitable solvent systems and the preparative HSCCC was used for larger scale separation and purification. Dehydrocavidine was analysed by high-performance liquid chromatography (HPLC) and further identified by ESI-MS and 1H NMR.

RESULTS

The optimised MAE experimental conditions were as follows: extraction temperature, 60 degrees C; ratio of liquid to solid, 20; extraction time, 15 min; and microwave power, 700 W. In less than 4 h, 42.1 mg of dehydrocavidine (98.9% purity) was obtained from 900 mg crude extract in a one-step separation, using a two-phase solvent system composed of chloroform-methanol-0.3 m hydrochloric acid (4 : 0.5 : 2, v/v/v).

CONCLUSION

Microwave-assisted extraction coupled with high-speed counter-current chromatography is a powerful tool for extraction, separation and purification of dehydrocavidine from C. saxicola.

Recent analytical approaches in quality control of traditional Chinese medicines--a review

Traditional Chinese medicines (TCMs) are gaining more and more attention all over the world, due to their specific theory and long historical clinical practice. But the uncontrollable quality is a bottleneck for its modernization and globalization. This paper reviewed the recent analytical methods in the quality control of TCMs, including screening strategies of bioactive markers from TCMs through biochromatographic methods, the traditional chromatographic methods, DNA methods, as well as the spectroscopic methods, including FT-IR, NIR and NMR. The comprehensive methods, such as fingerprint and multi-component quantification are emphasized; hyphenated techniques, like HPLC-MS, GC-MS, CE-MS, LC-NMR, chemometric methods, and combination of chemical and biological methods, such as biofingerprint, metabolic fingerprint are now more and more widely used in TCMs. In a few word, the analysis and quality control of TCMs are moving towards an integrative and comprehensive direction, in order to better address the inherent holistic nature of TCMs.

Rapid analysis of the essential oil components of dried Perilla frutescens (L.) by magnetic nanoparticle-assisted microwave distillation and simultaneous headspace solid-phase microextraction followed by gas chromatography-mass spectrometry

In this work, two solvent-free sample preparation techniques of microwave distillation (MD) and headspace (HS) solid-phase microextraction (SPME) were combined, and developed for the determination of essential oil compounds in dry traditional Chinese medicine (TCM). Amine-functionalized magnetite nanoparticles (AMNs) were added and mixed with the dried Perilla frutescens (L.) sample, which was used as a microwave absorption solid medium for dry distillation of the TCM. Using the proposed method, isolation, extraction and concentration of TCM essential oil compounds can be carried out in a single step. The AMN-assisted MD-HS-SPME parameters including fiber coating, microwave power, irradiation time, and the amount of added AMN were studied. The optimal analytical conditions were: fiber coating of 100 µm PDMS/DVB, microwave power of 230 W, irradiation time of 2 min, as well as the addition of 0.1 g AMN to the TCM sample. The proposed method is applied to the determination of essential oil in Perilla frutescens (L.) and the RSD values is less than 9%. To demonstrate the method feasibility, the conventional HS-SPME method was also used for the analysis of essential oil in the TCM. Experimental results show that more compounds were isolated and identified by AMN-assisted MD-HS-SPME than those by HS-SPME. It was found that the proposed method is an alternative tool for the fast analysis of essential oils in dry TCMs.