Rapid Diagnostic PCR Assay Method for Species Identification of Mantidis Ootheca (Sangpiaoxiao) Based on Cytochrom C Oxidase I (COI) Barcode Analysis

Abstract

Mantidis Ootheca (sangpiaoxiao), the egg case of the mantis, is a type of insect-derived traditional medicine widely used in East Asia. However, species identification based on egg morphology is challenging, leading to the distribution of counterfeit and adulterated products. The use of inauthentic ingredients can pose serious health risks to consumers. This study aimed to develop PCR markers that can rapidly and accurately differentiate between authentic and counterfeit Mantidis Ootheca. The mitochondrial cytochrome c oxidase I (COI) region was sequenced in thirteen samples from four mantis species: Tenodera angustipennis, Statilia maculata, Hierodula patellifera, and T. sinensis. Four sets of SCAR primers were designed based on species-specific nucleotide polymorphisms, and a multiplex SCAR assay was developed by combining all sets of the primers. The sequence-characterized amplified region (SCAR) primers successfully produced amplicons for each target species, even with low-DNA templates or templates containing DNA from multiple samples. No amplification was observed for nontarget species. This study presents a novel approach for identifying authentic Mantidis Ootheca species using DNA-based diagnostic marker assays, which enable rapid and precise species identification. The SCAR assays developed in this study will aid in maintaining quality control and promoting the standardization of commercial Mantidis Ootheca products.