Mauji Ram

SCAR markers: a potential tool for authentication of herbal drugs.

Randomly Amplified Polymorphic DNA (RAPD) is easy to develop and simple molecular marker, but lack of reproducibility makes it less reliable for authentication of herbal drugs. Besides RAPD, other popular PCR and non-PCR based markers like AFLP, ISSR, SSR and RFLP are also used for authentication. However, these also have disadvantages like use of radioactive isotopes, high cost and absolute requirement of sequence information. Therefore, it is a better option to improve the reproducibility of RAPD by converting RAPD amplicons into Sequence Characterized Amplified Region (SCAR) markers. SCAR markers are easy, reliable and reproducible thus, have an advantage over RAPD markers for authentication of medicinal herbs used in the preparation of traditional medicines. These markers however, have been developed for only a few medicinal herbs. This review is an attempt to evaluate critically the role of SCAR markers in authentication of medicinal herbs used in traditional formulations.

Enhancement of artemisinin content by constitutive expression of the HMG-CoA reductase gene in high-yielding strain of Artemisia annua L.

Artemisinin is effective against both chloroquine-resistant and -sensitive strains of Plasmodium species. However, the low yield of artemisinin from cultivated and wild plants is a serious limitation to the commercialization of this drug. Optimization of artemisinin yield either in vivo or in vitro is therefore highly desirable. To this end, we have overexpressed the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR) gene (hmgr) from Catharanthusroseus L. in Artemisia annua L. and analyzed its influence on artemisinin content. PCR and Southern blot analyses revealed that the transgenic plants showed stable integration of the foreign hmgr gene. The reverse transcriptase-PCR results suggested that the hmgr was expressed at the transcriptional level in transgenic lines of Artemisia annua L., while the high-performance liquid chromatography analysis showed that artemisinin content was significantly increased in a number of the transgenic lines. Artemisinin content in one of the A. annua transgenic lines was 38.9% higher than that in non-transgenic plants, and HMGR enzyme activity in transgenic A. annua L. was also higher than that in the non-transgenic lines.

Fusarium solani, P1, a new endophytic podophyllotoxin-producing fungus from roots of Podophyllum hexandrum

Podophyllotoxin, a well-known naturally occurring aryl tetralin lignan produced by few plant species is used as precursor for the chemical synthesis of the anticancer drugs like etoposide, teniposide and etopophos phosphate. The availability of this lignan is limited due to the scarce occurrence of its natural sources. Further, synthetic approaches for its production are still commercially unacceptable. This paper reports the synthesis of podophyllotoxin by an endophytic fungus Fusarium solani isolated from the roots of Podophyllum hexandrum. The presence of podophyllotoxin in fungal biomass was confirmed and quantified by HPLC and mass spectrometry. The fungus is able to produce 29.0 µg/g podophyllotoxin on dry weight basis.

HPTLC Fingerprint Analysis: A Quality Control for Authentication of Herbal Phytochemicals

Authentication and consistent quality are the basic requirement for Indian traditional medicine (TIM), Chinese traditional herbal medicine (TCHM), and their commercial products, regardless of the kind of research conducted to modernize the TIM and TCHM. The complexities of TIM and TCHM challenge the current official quality control mode, for which only a few biochemical markers were selected for identification and quantitative assay. Referring too many unknown factors existed in TIM and TCHM, it is impossible and unnecessary to pinpoint qualitatively and quantitatively every single component contained in the herbal drug. Chromatographic fingerprint is a rational option to meet the need for more effective and powerful quality assessment to TIM and TCHM. The optimized chromatographic fingerprint is not only an alternative analytical tool for authentication, but also an approach to express the various pattern of chemical ingredients distribution in the herbal drugs and preserve such “database” for further multifaced sustainable studies. Analytical separation techniques, for example, high-performance liquid chromatography (HPLC), gas chromatography (GC) and mass spectrometry (MS) were among the most popular methods of choice used for quality control of raw material and finished herbal product. Fingerprint analysis approach using high-performance thin-layer chromatography (HPTLC) has become the most potent tool for quality control of herbal medicines because of its simplicity and reliability. It can serve as a tool for identification, authentication, and quality control of herbal drugs. In this chapter, attempts are being made to expand the use of HPTLC and at the same time create interest among prospective researcher in herbal analysis. The developed method can be used as a quality control tool for rapid authentication from a wide variety of herbal samples. Some examples demonstrated the role of fingerprinting in quality control and assessment.

Structural and functional characterization of HMG-COA reductase from Artemisia annua.

Plants synthesize a great variety of isoprenoid products that are required not only for normal growth and development but also for their adaptive responses to environmental challenges. However, despite the remarkable diversity in the structure and function of plant isoprenoids, they all originate from a single metabolic precursor, mevalonic acid. The synthesis of mevalonic acid is catalysed by the enzyme, 3‐hydroxy‐3‐methylglutaryl coenzyme A reductase (HMG‐ CoA reductase). The analysis of the amino acid sequence of HMG‐CoA reductase from Artemisia annua L. plant showed that it belongs to class I HMG‐CoA reductase family. The three dimensional structure of HMG‐CoA reductase of Artemisia annua has been generated from amino acid sequence using homology modelling with backbone structure of human HMG‐CoA reductase as template. The model was generated using the SWISS MODEL SERVER. The generated 3‐D structure of HMG‐CoA reductase was evaluated at various web interfaced servers to checks the stereo interfaced quality of the structure in terms of bonds, bond angles, dihedral angles and non-bonded atom-atom distances, structural as well as functional domains etc. The generated model was visualized using the RASMOL. Structural analysis of HMG-CoA reductase from Artemisia annua L. plant hypothesize that the N and C‐terminals are positioned in cytosol by the two membrane spanning helices and the C-terminals domain shows similarity to the human HMG‐CoA reductase enzyme indicating that they both had potential catalytic similarities.