Biological activities of Kalmegh (Andrographis paniculata Nees) and its active principles-A review

Kalmegh (Andrographis paniculata Nees) has wide range of medicinal and pharmacological applications. It is used in different traditional systems of medicine and exhibits anti-inflammatory, anti-HIV, antibacterial, antioxidant, antiparasitic, antispasmodic, antidiabetic, anticarcinogenic, antipyretic, hepatoprotective, nematocidal and various other activities. It is a potent scavenger of a variety of reactive oxygen species (ROS) including superoxide anion, hydroxyl radical, singlet oxygen, peroxynitrite and nitric oxide. Among several active chemical constituents, andrographolide, neoandrographolide and dehydroandrographolide are most important bioprotectants with wide range of therapeutic applications. Andrographolides significantly inhibit the expression of iNOS, COX-2, mRNA, protein, enzyme activity in RAW 264.7 macrophages that involves in anti-inflammatory activity. Kalmegh extract protects lipids, haemoglobin and red blood cells from lipid peroxidation. It prevents oxidative damage and inhibits binding to toxic metabolites to DNA. Safety evaluation studies indicate that kalmegh is well tolerated at very high dose without any toxic effects.