PCR–RFLP to distinguish three Phyllanthus sp., commonly used in herbal medicines

The herbs Phyllanthus amarus, P. fraternus and P. urinaria, are known for their use in preparation of herbal medicines. These herbs grow together and are morphologically indistinguishable. Hence, collections of these herbs for raw drug trade, frequently contain mixture of the three species. Such mixing can result in preparation of herbal drugs with altered efficacy. To prevent this, it is essential to develop reliable methods/markers for accurate identification of species. Keeping this in view, PCR–RFLP (Polymerase Chain Reaction–Restriction Fragment Length Polymorphism) of chloroplast genome regions was carried out, using six pairs of universal primers of chloroplast DNA for amplification, followed by restriction with HinfI and TaqI in P. amarus, P. fraternus and P. urinaria. Distinct restriction patterns for the three species were obtained in all primer pair-restriction enzyme combinations. Since the primers used are conserved over a wide range of plant taxa, PCR–RFLP technique using universal cpDNA primers may be applied to other medicinal/economically important plants, posed with similar problems of identification.