## 1 Introduction  
_Farfugium japonicum_ (L-) Kitamura is a member of the Asteraceae family of herbal plants [1]. It has a wide distribution in East Asia, in countries such as Japan, Korea, and China. _F. japonicum_ grows both in poor soils and in riverside areas, and it has a variety of leaf shapes, ranging from stenophyllous to spherical [2]. _F. japonicum_ commonly exhibits large, heart-shaped leaves that are randomly spotted with yellow dots, and they look similar to a lotus leaves or a horseshoe. In traditional Chinese medical therapy, _F. japonicum_ rhizces have been used to treat sore throats, colds, and coughs. In addition, modern pharmacological studies have shown its antipyretic, analgesic, antitumor, and anti-inflammatory activities [3]. It is reported that total flavonoids from the aerial parts of _F. japonicum_ are more active against bacteria (_Bacillus subtilis_, _Salmonella_, _Staphylococcus aureus_, and _Escherichia coli_) than fungi (_Penicillium_ and _Apergillus niger_) [4]. Chemical compounds such as benzofuranosesquiterpenes (farfugin A and farfugin B) [5], furanoeremophilane (3\(\beta\)-angeloyloxy-10\(\beta\)-hydroxy-98-seneocioyloxyfuranoeremophilane and 3\(\beta\)-angeloyloxy-10\(\beta\)-hydroxyfuranoeremophilane) [6], and the pyrrolidine alkaloid farfugine [7] have been isolated. Additionally, a previous report examining chemical composition of _F. japonicum_ flower oil highlighted its main components and demonstrated anti-inflammatory effects [1]. Volatiles are secondary metabolites that are generated by many plants. They are also referred to as ethereal oils. They are described as being volatile, naturally occurring, and odorous compounds, and they are utilized in the production of various items, including food flavors, perfumes, cleaners, pesticides, herbicides, and medicines [8]. The active benefits of volatiles are demonstrated in a variety of ways, including the effects of excitement, antioxidant, bacteriostasis, and virtustatic activities, demonstrating wide applications in terms of suitable medicine dosage forms, such as a tablet, lotion, spray, drop pill, soft capsule, microemulsion, gel paste, microcapsule, microsphere, liposome, polymer micelle, and so on [9]. The supercritical fluid extraction of the CO2 (SFE-CO2) process is becoming a highly appreciated, environmentally friendly, and effective plant extraction technology, and there have been increasingly broader applications over the past few decades. This avoids the shortcomings of traditional methods including poor purity, weak efficacy, solvent residue, and environmental pollution [10]. Compared to other fluids, supercritical CO2 is more suitable for the extraction of essential oils with its high solubility and diffusivity, safe and tasteless characteristics, and feasible critical temperature. To some extent, it restores the natural color, composition, and fragrance of the volatile oil with controllability [11]. According to previous studies [12; 13], the terpenids and phenols in volatiles are recognized for their antioxidant and antibacterial components. However, there are some important factors affecting the quality and ingredient composition in terpenids and phenols, such as the extraction methods used, plants organs, and compounds ingredients etc. An SFE-CO2 extraction method may be one of the best choices for extracting volatile oils due to its advantages of CO2 compatibility with volatiles, high efficiency, greenness, and low temperature extraction. In terms of plant organs, the leaf and stem usually show differences in volatile compounds, leading to further diversity in their biological activities [14]. However, the mechanism producing such results has not been fully clarified. As an example, the volatiles involved in the structure of oxygenated terpenids have been proven to have good antimicrobial and antioxidant capacities [15], and it is necessary to further test and verify the universal applicability of this to all plant organs.