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Korean Medicine (KM), a traditional medical system with a history spanning thousands of years, has long been utilized for disease prevention, symptom alleviation, and health promotion (Kwon et al., 2017). In recent years, KM has expanded its industrial horizons by converging with the functional food, natural pharmaceutical, and cosmetic sectors, thus presenting new opportunities for innovation and commercialization (Shin and Park, 2019). This multidisciplinary expansion has led to a marked increase in the consumption of herbal medicines, consequently generating large quantities of herbal medicine waste (HMW) during manufacturing, extraction, and formulation processes (Shin and Park, 2019). Addressing the treatment and utilization of this waste has emerged as a critical social and environmental challenge.

Traditionally, herbal medicine waste has been treated as ordinary refuse, with disposal methods such as landfilling or incineration being the predominant practices (Lu and Li, 2021). However, there is growing recognition that HMW contains residual bioactive compounds and holds promise as a valuable biorefinery resource. Indeed, herbal residues are known to contain flavonoids, saponins, polysaccharides, alkaloids, and other bioactive substances, which have been scientifically demonstrated to exert anti-inflammatory, antioxidant, antimicrobial, and immunomodulatory activities (Yatoo et al., 2018; Harikrishnan and Balasundaram, 2020; Prabhu et al., 2024). Despite this, the majority of HMW is currently disposed of without adequate separation or processing, leading to a dual problem of environmental pollution and resource wastage.

The challenge of HMW management is not confined to Korea; it is a shared industrial issue among East Asian countries where traditional medicine systems are institutionalized, including Traditional Chinese Medicine (TCM) and Kampo medicine in Japan (Harikrishnan and Balasundaram, 2020). In Korea, reports by the Ministry of Health and Welfare and related academic societies estimate that as of 2020, the annual consumption of herbal medicine exceeds 60,000 tons (Izah et al., 2024). This generates substantial amounts of waste across various settings, including Korean medicine hospitals, clinics, and manufacturing facilities (Izah et al., 2024). Notably, herbal decoction residues and other by-products from processes such as pharmacopuncture and formulation are often classified as medical waste and incinerated (Zhang and Wong, 2023). This practice has been criticized not only for squandering useful resources but also for exacerbating environmental burdens. Although some municipalities and enterprises have recently attempted to recycle herbal waste into agricultural resources or environmental materials, the technological infrastructure and regulatory frameworks remain underdeveloped.

China, where the TCM industry has seen rapid expansion, produces an estimated 60 to 70 million tons of herbal residues annually (Tao et al., 2021; Zhang and Wong, 2023). Much of this waste is still processed through landfilling, incineration, or open dumping (Wu et al., 2025). While TCM has attracted global attention for its potential in treating refractory diseases such as cancer, liver disease, atherosclerosis, and even COVID-19, the environmental impact of its waste management remains a pressing issue (Huang, Y. F. et al., 2020; Li et al., 2020). In response, China has seen a surge of research into resource utilization strategies, including thermochemical conversion, biochemical conversion, and composting technologies (Li et al., 2020).

In Japan, Kampo medicine has been integrated into the formal healthcare system, with licensed physicians prescribing it as part of routine care (Payyappallimana and Serbulea, 2013; Yoshino et al., 2023). Major pharmaceutical companies, such as Tsumura and Chuo Yakuhin, consume tens of thousands of tons of herbal material annually, employing large-scale extraction systems (Alamgir, 2017a). Some of these companies operate in-house recycling systems to manage their waste (Başaran, 2012). Japan, known for its stringent environmental regulations, has also explored composting and biomass energy conversion as methods of utilization (Kataya et al., 2023). However, challenges remain in standardizing treatment technologies and fostering industrial collaboration.

Collectively, the bioconversion of HMW has emerged as an industrial and environmental priority across Korea, China, and Japan. Addressing this issue requires integrated discussions encompassing scientific, technological, and institutional approaches. Notably, the composition of herbal residues, largely composed of lignocellulosic biomass, renders them highly suitable as feedstocks for biorefinery applications. This has led to a paradigm shift in which herbal waste is increasingly viewed not as a disposal problem, but as a promising source of high-value bioresources. Technologies such as thermochemical conversion and biochemical conversion are now being actively investigated and applied in this paper.

To date, research on HMW valorization has primarily focused on individual technologies or case-specific studies. Comprehensive reviews that systematically examine the industrialization and productization potential of these approaches remain scarce. Accordingly, this paper aims to provide a holistic review of the major sources and compositional characteristics of HMW, followed by an integrated discussion of various technological approaches, including composting, thermochemical conversion, biochemical conversion, and the development of adsorbent materials.

Importantly, this review adopts an expanded concept of resource utilization that goes beyond mere waste disposal or the production of primary materials. Instead, it emphasizes the direct transformation of HMW into final functional products for use in the functional food, pharmaceutical, and cosmetic sectors. This involves preserving and exploiting the residual bioactive components in herbal waste to develop high-value applications, positioning the entire process chain from extraction to application as a core element of resource valorization.

Based on this framework, the paper analyzes how each technology facilitates the extraction and processing of active ingredients into industrial products, thereby exploring the potential for creating a high-value, circular ecosystem within the KM industry. Furthermore, the paper goes beyond assessing technical feasibility to examine the policy and institutional foundations needed to support this transformation, ultimately proposing a strategic roadmap for ensuring the sustainability and industrial expansion of Korea’s KM sector.

This review categorizes the technologies for HMW resource utilization by type, linking them to the specific end products they generate (e.g., energy, functional materials, environmental adsorbents) and exploring their potential applications in the functional food, pharmaceutical, and cosmetic industries. The review also examines the evolution of technological developments and recent case studies, providing an application-oriented analytical perspective that highlights industrialization potential and policy implications. By focusing on research advances from the past decade, this paper captures recent technological trends and the expanding scope of applications, underscoring the potential of HMW valorization as part of a broader strategy for industrial ecosystem transformation.

Fig. 1. 
Processing and bioresource utilization pathways of various Korean medicinal herb residues. Herbal medicine residues are generated from different parts of medicinal plants, including roots, rhizomes, stems, above-ground rhizomes, leaves, flowers, and fruits. Residual biomass arises from both the removal of non-medicinal plant parts during pretreatment and from traditional or targeted extraction processes such as decoction or bioactive compound extraction. These residues represent potential bioresources for diverse applications, including composting, thermochemical and biochemical conversion, and functional material production.

Herbal medicine waste (HMW) can be broadly categorized into two main types based on its generation pathway and form (Lu and Li, 2021). The first category consists of plant by-products generated during the pretreatment stage, where non-medicinal parts of herbal materials are removed (Lu and Li, 2021; Jouyandeh et al., 2022). Since most herbal medicines utilize only specific parts of plants, such as roots, stems, leaves, flowers, or fruits a substantial amount of plant waste is produced during the elimination of unnecessary portions (Luo et al., 2023). For instance, in the case of medicinal herbs like Panax ginseng or Glycyrrhiza uralensis, which primarily use roots, stems and leaves become waste; conversely, herbs such as Schizonepeta tenuifolia or Schisandra chinensis, which rely on above-ground parts, leave roots as waste (Zhang et al., 2020; Shang et al., 2022; Zhao and Zhou, 2022).

The second category comprises residues remaining after decoction or extraction of active constituents. Commonly referred to as “herbal decoction residues” or “herbal extraction by-products,” these wastes are generated in large quantities at clinical sites (such as Korean medicine clinics and hospitals) and manufacturing facilities. Herbal medicines are often used in the form of decoctions or concentrated extracts, leaving behind moist solid residues after extraction. Although these materials may appear to be simple waste, numerous studies have reported that they retain considerable amounts of bioactive compounds (Fueki et al., 2015).

From a compositional perspective, HMW exhibits characteristics similar to those of typical agricultural biomass (Parmar, 2017). The primary structural components include cellulose, hemicellulose, and lignin, forming what is known as a lignocellulosic matrix (Monties, 1991). This structure offers physical stability while also presenting opportunities for conversion into high-value materials through various processing pathways.

In addition, HMW contains a wide range of residual bioactive compounds, including flavonoids, saponins, alkaloids, polyphenols, and tannins (Lu and Li, 2021). These compounds exhibit diverse biological activities, such as antioxidant, anti-inflammatory, antiviral, antimicrobial, and immunomodulatory effects, which confer high potential value as functional raw materials or additives (Lu and Li, 2021; Prabhu et al., 2024). Notably, the decoction process often exhibits low extraction efficiency for non-heat-stable components or high-molecular-weight polysaccharides, rendering the residues promising targets for subsequent valorization in the development of functional foods or pharmaceuticals (Lu and Li, 2021).

Despite this potential, HMW poses environmental and sanitary risks when treated as general waste due to its high moisture content and rapid decomposition rate (Lu and Li, 2021). Particularly in summer, the speed of decomposition accelerates dramatically, leading to odor generation, microbial contamination, and pest infestation, all of which present significant hygiene concerns (Luo et al., 2023). Therefore, prompt treatment and separation systems are required rather than simple storage.

HMW exists in diverse physical forms, including solid, semi-solid, and sludge-like states, with moisture content typically ranging from 60% to 80% (Luo et al., 2023). These high-moisture organic wastes are generally unsuitable for conventional thermal treatment methods but are well suited for biological or thermochemical resource conversion techniques, such as composting, fermentation, or biomass transformation (Begum et al., 2024).

The quantity and composition of HMW vary depending on the type of herbal material used, its formulation, and the extraction method employed. Compared to traditional decoctions, modern herbal preparations (such as concentrates, granules, and tablets) tend to generate more uniform residues (Alamgir 2017b). This uniformity offers advantages for applying standardized resource recovery processes, enhancing their industrial utilization potential (Alamgir, 2017b).

Moreover, the feasibility of HMW utilization is highly dependent on the classification and compositional information of the resource in question. Because residual constituents and functions differ among herbal species, precise classification, pretreatment, and compositional analysis in the pre-conversion stage are essential (Huang et al., 2021). For example, combining or separating residues from Schisandra chinensis, known for its high antioxidant activity, and Astragalus membranaceus, rich in anti-inflammatory compounds, enables the development of customized high-functionality materials (Zhao et al., 2024; Hao et al., 2025). Such fractionation strategies have been proposed as effective means for generating targeted functional ingredients (Hao et al., 2025).

For these reasons, HMW should not be regarded as mere waste but rather as an organic bioresource capable of regeneration through deliberate processing. It is crucial to establish a systematic resource recovery framework encompassing collection, sorting, and processing from the point of generation. Such a system is not only vital for addressing environmental challenges but also serves as an important foundation for enhancing the sustainability and economic viability of the herbal medicine industry.

Fig. 2. 
Overview of resource utilization technologies for herbal medicine waste. The figure illustrates four major conversion pathways composting, thermochemical conversion, biochemical conversion, and adsorbent production highlighting their respective outputs and inputs. Composting produces functional compost and soil amendments through microbial decomposition; thermochemical conversion generates biochar, bio-oil, biogas, and heat/energy via pyrolysis and gasification; biochemical conversion yields bio-adsorbents and cosmetic ingredients through fermentation; and adsorbent production creates materials for heavy metal removal, water purification, and antibacterial films through nanomaterial development. The diagram emphasizes the technological approaches and valorization strategies for transforming herbal medicine waste into high-value products.

Building upon the aforementioned resource utilization technologies, the following section outlines how these approaches are being translated into real-world applications across the functional food, pharmaceutical, and cosmetic industries. HMW is not merely organic waste but a bioresource rich in residual bioactive compounds. Polysaccharides, flavonoids, saponins, and alkaloids are widely used as key ingredients in functional foods, pharmaceuticals, and cosmetics, and are reported to remain at substantial levels even after extraction. Accordingly, HMW is a promising raw material for direct application in high-value products following appropriate refinement and conversion processes.

The valorization of HMW transcends environmental and technological challenges, holding the potential to create new high-value industries. Technologies such as composting, thermochemical conversion, and biochemical conversion have already demonstrated technical feasibility in other biomass sectors, and with appropriate adaptation, can be directly integrated into functional food, pharmaceutical, and cosmetic applications. However, successful large-scale industrialization requires strategies that comprehensively address technological maturity, economic viability, operational efficiency, and environmental safety.

Herbal medicine waste is not merely a by-product for disposal but a latent high-value bioresource rich in residual bioactive compounds. This review analyzed the primary generation pathways and biological and chemical characteristics of HMW and examined various resource utilization technologies, including composting, thermochemical conversion, biochemical conversion, and functional material production. It further discussed how the conversion products can directly connect to industrial sectors such as functional foods, pharmaceuticals, and cosmetics, confirming the potential of HMW valorization to link technologies, products, and industrial ecosystems. HMW, with its lignocellulosic structure and abundant bioactives such as polysaccharides, flavonoids, and saponins, can serve as a versatile feedstock for diverse functional products. This transforms waste management from simple organic treatment into a deliberate value-added product strategy.

Currently, most HMW is incinerated as medical or general waste, undermining its potential value and creating environmentally inefficient systems. However, if HMW is viewed as an inexpensive, usable biomass resource rather than a pollutant, it can become an attractive industrial material. The reviewed technologies including thermochemical, biochemical, and hybrid approaches demonstrate clear potential for producing energy, functional materials, and functional chemicals. By systematically integrating these technologies and designing appropriate equipment, efficient, stable, and eco-friendly waste management systems can be established.

Additionally, ensuring connectivity between technologies and preventing secondary pollution must be prioritized. For example, lignin-rich residues can be thermochemically processed after biochemical extraction, with the resulting energy reinvested in upstream processes, creating circular resource systems. Addressing residual contaminants, such as heavy metals and toxins, through rigorous safety assessments and treatments will also be critical.

Future research should focus on optimizing hybrid technologies to simultaneously achieve cost-efficiency, operational stability, and environmental safety. Developing nanozyme-based catalysts, high-efficiency equipment, and advanced pollution control technologies will be key. At the same time, regulatory support, such as demonstration projects, streamlined regulations, and certification standards will be essential to increase industrial uptake. Ultimately, HMW valorization is not only a technical solution to environmental problems but also a strategic springboard for enhancing the sustainability and competitiveness of the Korean Medicine industry. This review aims to provide foundational insights and directions toward realizing this vision through collaboration across academia, industry, and policymakers.