Recent advances in plant hepatoprotectives - CIMAP Staff - Central ...

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NEGI ET AL.
done on histopathological parameters in rats showed picroliv was non-toxic. 122 A similar experiment
done on adult rhesus monkeys showed no abnormality in food intake, daily activities, body weight,
hematology, and blood biochemistry.
F. Future Prospects
Picroliv was found to be a safe drug with no reported side effects. 123 Picroliv has successfully
completed phase I and phase II clinical trials and waiting for phase III clearance. Being a potent
hepatoprotective, this may emerge as a potent hepatoprotective drug in a near future.
6. PHYLLANTHIN AND HYPOPHYLLANTHIN
A. Introduction
Phyllanthin (13) and hypophyllanthin (14) are potent hepatoprotective lignans found in Phyllanthus
niruri Linn. (Family: Euphorbiacea). The genus includes more than 600 species of shrubs, trees, and
annual/biennial herbs distributed throughout the globe, many of which are used medicinally in
different countries such as P. emblica L., P. urinaria L., P. reticulates in Indo-China, P. niruri in Brazil
and West Indies, P. elegans Wall, P. urinaria in the Philippines. The plant is commonly known as
‘‘Bhuiamliki’’ in India and ‘‘Look Tai Bai’’ in Thailand. P. niruri is a small, erect, annual herb
that grows 30–60 cm in height mainly as a weed in both cultivated fields and wastelands. It is a wellknown
Ayurvedic plant used in folk remedy for jaundice and other liver disorders.
B. Chemistry
Chemically, both phyllanthin (13) and hypophyllanthin (14) are lignans (Fig. 10). 124,125 Phyllanthin
is linked through C8–C8 0 of phenyl propanoid units, while hypophyllanthin is additionally linked
through C2–C7 0 to make a tetrahydronaphthalene ring system. The stereochemistry of phyllanthin
was established as 8(S), 8 0 (R). 126 Phyllanthin and hypophyllanthin have been isolated from the
hexane extracts of P. niruri.
A complete spectral studies 127 including single crystal X-ray analysis 128 have left no doubt on
the full 3-dimensional structural characterization of phyllanthin and hypophyllanthin. Being
important markers of the medicinal plant, several HPTLC methods have also been developed for
quantitative estimation of these molecules. 129
C. Biological Activity
The plant has been effective against infective hepatitis 130,131 and other disorders of liver. 132–134 The
hexane fraction of the ethanolic extract showed potent hepatoprotective activity. Its liver protective
effects have been established by various in vitro and in vivo experiments in rats and mice. Human
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Medicinal Research Reviews DOI 10.1002/med
Figure 10. Structures of phyllanthin (13) and hypophyllanthin (14).