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    New Insights in Pesticide Registration: Application of “Chemical Fingerprinting” in Botanical‑Based Pesticides


    Release Date:

    2018-06-20

    Ministry of Agriculture Announcement No. 2569 establishes a classification-based management system for plant‑derived pesticide active ingredients (technical grades) in the registration requirements. Based on whether the plant source has been used extensively over a long period, such active ingredients are categorized into Class I and Class II. Class I plant‑derived pesticide active ingredients: The plant source is widely used. In this case, a compositional analysis report must be submitted, including at least qualitative and quantitative data on the active ingredient or marker active ingredient, relevant impurities, and solvents, as well as “chemical fingerprint” profiles for five batches of the product. Class II plant‑derived pesticide active ingredients: The plant source has not been widely used. Should…

    Agriculture Ministry Announcement No. 2569, concerning plant-derived… Pesticide In the registration requirements for active ingredients (technical-grade materials), for plant-derived substances… Pesticide Implement categorized management, classifying plant-derived substances into Category 1 based on whether they have been widely and extensively used over a long period. Pesticide Parent compound and Category 2 plant-derived substance Pesticide Parent drug.

     
    Category 1: Plant-derived Pesticide Parent drug: The plant material used is widely employed. In such cases, a compositional analysis report for the parent drug shall be submitted, containing at least qualitative and quantitative data on the active ingredient or marker constituent, relevant impurities, and solvents, as well as “chemical fingerprint” profiles for five batches of the product.
     
    Category 2, plant-derived Pesticide Parent drug: The plant material used has not been widely employed. A complete compositional analysis report for the parent drug shall be submitted, including at least the following: the active constituent(s) or marker active constituent(s), relevant impurities, components with peak areas ≥ 10% of the main peak area, and components present at ≥ 1%; qualitative and quantitative analytical data for solvents; and “chemical fingerprint” profiles for five batches of the product. The sum of the quantitatively determined contents of all identified constituents must not be less than 80%.
     
    Requirements for the identification of active ingredients or marker compounds in plant‑derived formulation products during registration: (1) For formulations prepared from the technical grade material, at least one analytical method must be used to identify the active ingredient. When chemical methods are employed, at least two distinct identification assays shall be provided; (2) For formulations prepared from a parent compound, identification shall be based on characteristic peaks and retention times derived from the formulation’s “chemical fingerprint” profile.
     
    Modern “fingerprint” identification originated in criminology and forensic science at the turn of the 19th and 20th centuries. With advances in genetics, the concept of fingerprint analysis has been integrated with biotechnology, extending to DNA fingerprinting; its applications have expanded from criminology into medicine and the life sciences. The use of fingerprinting techniques for quality control of natural products dates back to the early 1970s. In a broad sense, fingerprinting encompasses both chemical fingerprints and DNA fingerprints, whereas in a narrower sense, it refers exclusively to chemical fingerprints. Compared to its application in… Pesticide Applications in this area need to be even more diverse.
     
    In recent years, both domestic and international researchers have developed a variety of methods for constructing fingerprint profiles of traditional Chinese medicines, including thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), gas chromatography (GC), high-speed counter-current chromatography (HPSCCC), high-performance capillary electrophoresis (HPCE), infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), X-ray diffraction, as well as liquid chromatography–tandem mass spectrometry (LC‑MS/MS) and gas chromatography–mass spectrometry (GC‑MS). Among these, chromatographic techniques constitute the mainstream approach to fingerprint profiling; in particular, TLC, HPLC, and GC have become widely recognized as the three standard analytical methods.
     
    As is well known, traditional organic synthesis Pesticide The various adverse effects associated with long-term use—such as the development of resistance in pest organisms, residual toxicity, and environmental pollution—have become a significant threat to human health, food safety, ecological balance, and social development. Consequently, there is growing demand for the development of highly effective, low-toxicity pest control agents, particularly those derived from plants. Pesticide Research and development is the key to addressing current chemical challenges. Pesticide An important research direction for many adverse effects. Chemistry Pesticide Its active ingredients are relatively simple, with clear targets, making it easy to detect and analyze, and also straightforward to specify the content and names of the effective components, unlike chemical… Pesticide Different, plant-based Pesticide The composition is rather complex, and many of its constituents exhibit biological activity; however, they vary in both concentration and potency, making it difficult to clearly label the product as plant-derived. Pesticide The names and amounts of all active ingredients. In Pesticide During the registration process, it is required to specify the chemical. Pesticide The content and names of the active ingredients must be specified, and even the levels and identities of impurities are required to be clearly defined. In toxicity testing, both the technical-grade material and its impurities must undergo toxicity assessment; however, for plant-derived… Pesticide In practice, these requirements are difficult to meet. For example, matrine-based insecticides may contain more than 50 alkaloids or other insecticidal constituents; it is challenging to obtain reference standards for all 50-plus active ingredients, and equally difficult to perform quantitative analyses on such a large number of components. Consequently, it is hard to precisely determine the content and identity of each active constituent, as well as the relative proportions among them.
     
    China’s plant-derived Pesticide In the development of quality standards, the primary approach involves using analytical techniques such as HPLC or GC to quantify a specific major active constituent, with the level of this constituent serving as the basis for assessing product quality. However, this quality-control paradigm fails to provide a comprehensive and holistic assessment of plant‑derived products. Pesticide Changes in product quality, which have consequently given rise to plant-based… Pesticide Certain market irregularities, such as uneven product quality, significant variations in efficacy among preparations of the same type produced by different manufacturers or among batches from the same manufacturer, and poor formulation stability, have been observed. Consequently, plant‑derived… Pesticide Quality and stability issues have become bottlenecks hindering its development.
     
    Plant-derived Pesticide Typically, the labels indicate the most representative active ingredients with both high content and potency, such as 0.3% azadirachtin emulsifiable concentrate, 2.5% rotenone emulsifiable concentrate, 0.25% matrine emulsifiable concentrate, and 0.04% oxymatrine aqueous solution. However, this approach does not fully and accurately characterize plant‑derived products. Pesticide the nature of the substance. For example, a 0.3% neem oil emulsion lists azadirachtin A as its active ingredient; however, the content of azadirachtin B alone can account for 1/8 to 1/3 of that of azadirachtin A in the formulation, and the two exhibit no fundamental difference in activity. Pure azadirachtin A and seed The activity of the methanol extract (containing approximately 1% azadirachtin A) also did not show substantial differences. During toxicity assessments, it is likewise challenging to conduct toxicity tests on all more than fifty active constituents. Furthermore, it is equally difficult to evaluate plant‑derived… Pesticide It is difficult to conduct standalone toxicity assessments on the impurities in the technical-grade active ingredient, as they require separate isolation, identification, and quantitative analysis. For instance, in 0.3% neem oil emulsifiable concentrate and 0.23% rotenone emulsifiable concentrate, nearly 80% of the components in the technical-grade material may be inactive. By isolating and identifying each impurity individually, obtaining reference standards, and performing quantitative analysis and toxicity testing on these impurities, the evaluation of plant‑derived products can be significantly enhanced. Pesticide the registration costs. Therefore, fingerprinting technology can be integrated into the quality-control system for plant-derived materials; its distinctive characteristics enable effective authentication of plant samples, while establishing quantitative criteria based on the areas and ratios of key characteristic peaks allows for robust quality control and ensures relative stability of sample quality.
     
    However, fingerprinting technology in plant-derived… Pesticide Few studies have reported that, for example, Zuo Jinliang et al. used RP‑HPLC to simultaneously determine the contents of sanguinarine, chelerythrine, and protopine in the medicinal material of Chelidonium majus; this also represents a fingerprint profile in plant‑derived materials. Pesticide One of the earliest reports in this field; Liu Lina et al. employed high-performance liquid chromatography–electrospray/quadrupole–time-of-flight tandem mass spectrometry, conducting compound identification by comparing retention times, accurate molecular masses, and both primary and secondary mass spectra with those of reference standards. They also developed a quantitative method for determining matrine and oxymatrine in Picrasma quassioides. Their findings indicated that Picrasma quassioides contains trace amounts of matrine and oxymatrine, and that the levels of these compounds vary considerably among different geographic origins and plant parts. The established method is specific and highly sensitive, making it suitable as a basis for the identification of matrine and oxymatrine in Picrasma quassioides.
     
    Fishvine root is a classic insecticidal plant; however, its quality varies considerably from batch to batch, and it is closely linked to its place of origin. Currently, there is a lack of standardized quality criteria and a robust control system for fishvine root and its derived products. Chen Xiaojun et al. conducted HPLC analysis on the acetone cold‑extraction of Fengshun fishvine root, obtaining excellent chromatographic separation. By comparing with reference standards, they identified several compounds in the chromatogram, including genistein, rotenone, trans‑chalcone, pterocarpin, and dehydropterocarpin. In the methanol extract of Fengshun fishvine root, when the acetone cold‑extract was analyzed by HPLC, 37 peaks were observed at λ = 254 nm, whereas at λ = 240 nm, the number of peaks decreased to 34 (see Figures 1–2).
    The acetone cold‑extract of Fengshun Derris root was subjected to ten HPLC analyses. The results demonstrated that, during the stability study, both the relative standard deviations of retention times and peak areas for the established acetone cold extract were below 1.5%; in the precision study, the relative standard deviations of the relative retention times of the 37 common peaks were all less than 1.0%, and those of the mass fractions were all below 2%; furthermore, in the reproducibility test, the relative standard deviations of the relative retention times of all peaks remained under 1.5%, indicating good reproducibility. Consequently, the developed method is well suited for constructing the fingerprint profile of Derris root and provides a reliable foundation for establishing the entire fingerprint‑based analytical system.
     
    For agricultural active plants, fingerprint profiles can be used to authenticate their identity and assess their quality; as for plant-derived… Pesticide The product can serve as a quality standard, enabling the authentication of its genuineness, the control of batch-to-batch quality variations, and the evaluation of process rationality. The chemical constituents of agricultural active plants constitute a complex multi‑component system; therefore, their quality assessment should rely on analytical methods that are well suited to this system and capable of providing comprehensive identification information. However, existing approaches—such as microscopic identification, physicochemical analysis, and quantitative assays—are insufficient to address this challenge.
     
    Therefore, establishing an active‑plant fingerprint profile for agricultural use will enable a more comprehensive characterization of the types and quantities of chemical constituents present in plants, thereby facilitating the identification and evaluation of bioactive plants and plant‑derived products. Pesticide A comprehensive description and evaluation of product quality, which also aligns perfectly with plant-derived sources. Pesticide The development trend of Chinese herbal medicine. Specifically, this can be achieved by extracting and isolating the major bioactive constituents from natural plants, employing techniques such as HPLC, LC‑MS/MS, and GC‑MS for qualitative and quantitative analysis of these key components, and applying computer‑aided spectral interpretation to decipher chromatographic profiles, thereby generating fingerprint signatures and establishing high‑resolution fingerprint databases for different varieties and geographic origins. Furthermore, gray relational analysis and chemometric methods can be used to construct models that link fingerprint profiles with biological activities. On this basis, by integrating the individual fingerprint‑related constituents with their corresponding bioactivities, a “fingerprint‑activity” research framework can be established, effectively linking plant quality with its functional efficacy and facilitating elucidation of the underlying mechanisms of action. Consequently, the study and establishment of fingerprint profiles for bioactive plants are instrumental in enhancing the quality and reliability of plant‑derived products. Pesticide The establishment of product quality, quality management systems, and product quality standards holds significant guiding and practical value, and will effectively promote plant‑derived… Pesticide The healthy development of the industry.
     
    Today, with the thorough implementation of Ministry of Agriculture Announcement No. 2569, it is believed that… Pesticide Enterprise or Pesticide Researchers on plant-derived Pesticide The understanding and application of “chemical fingerprints” will continue to deepen. From a registration perspective, it is all the more important to strengthen research and knowledge exchange at this level, with the aim of contributing in the future to the advancement of plant‑based products. Pesticide Further development within the country.
     
    Author: Yu Yun Source: Pesticides

     

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