Determination of volatile components in different parts of Atractylodes macrocephala by headspace solid-phase microextraction gas chromatography-mass spectrometry
Atractylodes macrocephala Koidz., a perennial herbaceous plant belonging to the Asteraceae family, is used as medicine with its roots and stems. It has the effects of strengthening the spleen, nourishing qi, drying dampness, promoting diuresis, stopping sweating, and stabilizing pregnancy. Modern pharmacological research shows that Atractylodes macrocephala has pharmacological effects such as improving gastrointestinal function, anti-cancer, protecting nerves, and has potential therapeutic effects on diseases such as low immunity, cerebral ischemia, rheumatoid arthritis, depression, diabetes, etc. Volatile components are an important part of its pharmacological effects. Atractylon, a sesquiterpene compound, is one of the main active ingredients in Atractylodes macrocephala, which has pharmacological effects such as anti-tumor, hypotensive, and respiratory system protection.
At present, the extraction and analysis of Atractylodes macrocephala ketone mainly use steam distillation method, which has disadvantages such as low extraction efficiency and easy loss of compounds. Headspace solid phase microextraction technology (HS-SPME-GC-MS) is a fast and simple volatile component extraction technique that does not require tedious pre-treatment processes such as solvent extraction. It has the advantages of high extraction efficiency, short extraction time, low sample consumption, and minimal loss of volatile compounds. At present, it has been widely used for extracting volatile components from samples such as vegetables, fruits, and alcoholic beverages. Guo et al. used headspace solid-phase microextraction gas chromatography-mass spectrometry to separate and identify the volatile components in Atractylodes macrocephala, and compared them with the volatile components extracted by traditional steam distillation method. The main components extracted by the two methods were basically the same; Liu et al. used headspace liquid-liquid extraction gas chromatography-mass spectrometry to determine the volatile components in Atractylodes macrocephala, and compared them with the volatile components extracted by traditional steam distillation method. The results indicate that the components extracted by the two methods are basically the same and can be used for the determination of volatile components in Atractylodes macrocephala. The combination of headspace solid-phase microextraction and gas chromatography-mass spectrometry is more suitable for the extraction of volatile substances in Atractylodes macrocephala.
Zhang et al. found that Atractylodes macrocephala produced in Pingjiang, Hunan had a higher content of Atractylodes macrocephala ketone by comparing the content of Atractylodes macrocephala ketone in different regions. At present, research and development of Atractylodes macrocephala in Atractylodes macrocephala mainly focus on its main root, and there is relatively little research on other non medicinal parts of Atractylodes macrocephala. Therefore, for the first time, this experiment used the main root, fibrous root, stem, and leaf of Atractylodes macrocephala in Pingjiang as raw materials, and used HS-SPME-GC-MS technology to analyze the differences in the content of Atractylodes macrocephala in the four parts of Atractylodes macrocephala, and compared the differences in the volatile component composition of different parts, providing reference for the research and development of volatile components in non medicinal parts of Atractylodes macrocephala.

The experiment found that there are significant differences in the accumulation of volatile components in different parts of Atractylodes macrocephala. As the main active ingredient of Atractylodes macrocephala (see Figure 7), Atractylodes macrocephala accumulates mainly in the roots of Atractylodes macrocephala, and has a wide range of good pharmacological activities such as anti-tumor, blood pressure lowering, respiratory system protection, anti-inflammatory, analgesic, antioxidant, hepatoprotective, anti influenza virus, mite removal, etc; This study found that in addition to the traditional medicinal parts of Atractylodes macrocephala, the relative content of Atractylodes macrocephala ketone in its fibrous roots (25.85%) and leaves (5.98%) is also relatively high; During the harvesting season, the stems and leaves of Atractylodes macrocephala account for 40% of the entire plant, the main roots account for 40%, and the fibrous roots account for over 10%. However, the stems, leaves, and other parts are mostly treated as waste, which has great potential for development and utilization; Shao et al. found through studying the quality difference between the main root and the fibrous root of Atractylodes macrocephala that when the volatile components of Atractylodes macrocephala are the main active ingredients, the fibrous root of Atractylodes macrocephala can be considered as a substitute for the main root for medicinal use; As a widely demanded medicinal ingredient in the market, there is relatively little research on the quality control of Atractylodes macrocephala, and its large-scale development and utilization have been constrained by factors such as extraction technology and yield. This study can provide new ideas for its extraction and utilization. Atractylodes macrocephala ketone is extremely unstable and easily undergoes oxidation reaction with water at room temperature, producing compounds such as Atractylodes macrocephala lipid I and III. However, no lipids or related compounds were found in the four parts of Atractylodes macrocephala in this experiment. The reason for this is speculated to be that the volatile component extraction process uses headspace solid-phase microextraction, which avoids interference from other factors such as solvents and high temperatures, and the extraction time is relatively short. Based on this experiment, the combination of headspace solid-phase microextraction and gas chromatography-mass spectrometry has the characteristics of high efficiency, trace amount, and sensitivity, which can better reflect the composition and accumulation of volatile components in medicinal materials. Currently, it has been widely used in the field of detecting and analyzing volatile components from plant sources, such as Fructus Aurantii and Huanghua. It can provide technical choices and references for the detection and analysis of volatile components from plant sources such as Atractylodes macrocephala, and the analysis of biosynthetic pathways.

Secondly, it was found that there were significant differences in the types and relative contents of volatile components in Atractylodes macrocephala leaves compared to the other three; 45 volatile compounds were determined in the leaves, and terpenes are the main volatile oil components in Atractylodes macrocephala leaves. Among them, the relative content of Daphne D is the highest (18.74%), which has been proven to be a key antibacterial active ingredient in plants such as Artemisia annua and Salvia miltiorrhiza, and has been applied in the production of related products such as Artemisia argyi essential oil; At the same time, Daphne D has a strong attractive effect on pests, pathogens, etc., and can be used as a natural lead for repellents. D-limonene is a natural functional monoterpene with a relatively high content (12.89%) in Atractylodes macrocephala leaves, exhibiting significant anti-tumor, antibacterial, and anti-inflammatory activities; In addition, D-limonene is commonly used as a food additive in the food industry due to its aroma enhancing and antioxidant properties; In terms of pesticides, D-limonene has an attractive effect on certain insects and can also inhibit the growth of some weeds, making it suitable for natural insect and herbicide applications. In summary, the leaves, stems, and other parts of Atractylodes macrocephala have good prospects in the development and utilization of natural products.

Currently, there is a high demand in the market for Atractylodes macrocephala, and research on the volatile components of Atractylodes macrocephala is mostly focused on its medicinal parts such as roots and stems. There is relatively little research and development on its non medicinal parts such as leaves and fibrous roots. For example, Atractylodes macrocephala leaves are only treated as waste. If further research and development can be conducted on the non medicinal parts of Atractylodes macrocephala, it will improve resource utilization and alleviate the problem of resource scarcity. This experiment used headspace solid-phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) to determine the volatile components in different parts of Atractylodes macrocephala, elucidating the differences in volatile component composition between different parts, and providing a data basis for the development and utilization of volatile components in non medicinal parts of Atractylodes macrocephala; The traditional detection methods of Atractylodes macrocephala have problems such as easy conversion. This study can provide technical reference for the quality control of related medicinal materials such as Atractylodes macrocephala.