Medicinal Plants

General and Importance of Medicinal Plants

Systems of Medicine

  • There are mainly 3 systems of medicine practised in the world today. They are :

Modern System or Allopathy

  • This system was developed in the Western countries. In this system drugs (tablets, capsules, injections, tonics etc.) are manufactured using synthetic chemicals and / or chemicals derived from natural products like plants, animals, minerals etc. This system also uses modern equipment for diagnosis, analysis, surgery etc.
  • Medicines or drugs of this system is often criticised for its treatment of the symptoms rather than the cause of the disease, harmful side effects of certain drugs and for being out of reach of common / poor people due to the high cost of drugs and treatment.
  • This system is used in all the countries of the world today.

Alternative Medicine or Traditional System

  • Different countries of the world developed independently their own traditional systems of medicine using locally available materials like minerals and products of plants and animals.
  • The World Health Organisation is giving considerable importance to these alternate medicine (as they act as alternative to allopathy) systems to provide Primary Health Care to millions of people in the developing countries.
  • China developed the Chinese system of medicine, which is practised in China, Singapore, Taiwan, Japan and other countries.
  • In Indonesia, Jamu and in South Africa, Zulu systems of herbal medicine are practised. The Unani or Tibb system was developed in the Middle Eastern Arab countries and is practised in India and in many countries.
  • In India, Ayurveda (developed in North India), Siddha (developed in Tamil Nadu) and Nagarjuna (developed in Andhra Pradesh) systems of medicine were developed. Ayurveda is practised in Sri Lanka, Pakistan and Bangladesh also. Herbo-mineral is another traditional system used in India and other neighbouring countries.
  • Drugs (balms, oils, pills, tonics, paste etc) are manufactured and marketed in these systems. The major advantage of these systems is that they are within the reach of the people, particularly rural poor.
  • These systems are claimed to be pollution free, eco-freindly and have minimal or no harmful side effects. Ayurveda claims to cure the cause of the disease rather than the symptoms and is wholistic in its approach.
  • In this system a disease is conceived as an imbalance in the systems of the body and the treatment aims at restoring the balance in the various systems of the body.

Folk Medicine

  • The medicinal systems followed by various tribals / aborigins of different countries is popularly known as folk or tribal medicine.
  • In the system, the "medicine man" or the "doctor" of the tribe who has the knowledge of treating diseases, keeps this knowledge as a closely guarded secret and passes it to the next generation by word of mouth.
  • No written texts on these systems are available and different tribes follow different time tested methods. The treatment is often associated with lengthy and mystic rituals, in addition to prescription of drugs (decoctions, pastes, powders, oils, ashed materials etc.).
  • Mostly locally available natural materials are used for the preparation of drugs, which are not commercially made and marketed. Generally speaking, folk medicine can also be regarded as a traditional system of medicine.
  • The basic aim of all the above systems of medicine is to alleviate the sufferings of human beings and their domesticated animals.
  • The knowledge of the traditional systems is undergoing close scientific scrutiny and is being increasingly incorporated into the modern system.

Other Systems

  • Yoga, Acupressure, Acupuncture, Reiki, Magneto therepy, Pyramid therapy, Flower therapy, Homeopathy, Nature Cure or Naturopathy etc. are some of the other systems of medicine practised in different parts of the world today.

Top

Importance of Medicinal plants

Important Medicinal Plants and their active constituents

Plant
Active principle
Pharmacological activity
1 Rauvolfia serpentina Reserpine Hypotensive
2 Catharanthus roseus Ajmalicine Vasodilator
  Vinblastine Anticancer
  Vincristine Anticancer
3 Cassia angustifolia, Cassia acutifolia Sennosides Laxative
4 Plantago ovata Psyllium mucilage Laxative
5 Glycyrrhiza glabra Glycyrrhizic acid Antiinflammatory
6 Berberis sp. Berberin Antidiarrhoeal
7 Digitalis lanata Digitoxin Lanatoside Cardiotonic
8 Taxus baccata Taxol Anticancer
9 Podophyllum emodi Podophyllotoxin
Etoposide
Tenoposide
Anticancer
10 Datura species,
Hyocymus musticus,
Duboisia myoporoides

Hyoscine
Syoscyamina
Atropine
Parasympatholytic
11 Artemisai annua Artemisinin Antimalarial
12 Mappia foetida Camptothecine Anticancer

Medicinal Plants used as Crude Extracts / Tinctures in Medicines

Botanical Name
Common Name
1 Belladonna Atropa belladonna
2 Ipecac Cephaelis ipecacuanha
3 Opium Papaver somniferum
4 Henbane Hyoscyamus niger
5 Stramonium Datura stramonium
6 Liquorice Glycyrrhiza glabra
7 Rhubarb Rheum officinale
8 Podophyllum Podophyllium emodi
9 Capscicum oleoresin Capsicum annum
10 Digitalis Digitalis lanata, Digitalis purpurea
11 Aloe Aloe vera

Important Plant Products having great potential in Medicine

Plant Product
Source
Pharmacological activity
1 Valepotriates Valeriana wallichii Sedative, tranquilizer
2 Silymarin Silybum marianum Antihepatoxic
3 Podophyllotoxin (Etoposide/tenoposide) Podophyllum emodi, P. pellatum Anticancer
4 Taxol Taxus baccata Anticancer
5 Guggul saponins Cormmiphora wiightii Hypolipidaemic
6 Artemisinin Artemisai annua Antimalarial

Some important medicinal plants suggested for cultivation

Botanical name of the plant
Common
Aegle marmalos
Bilva (Hindi); Maredu (Telugu)
Glycyrrhiza glabra
Mulethi (Hindi); Athimadhuramu (Telugu)
Gmelina arborea
Gambhiri (Hindi); Gummadi (Telugu)
Mesua ferrea
Nagkesara (Hindi); Keearamu (Telugu)
Piper longum
Pipli (Hindi); Pippali (Telugu)
Picrorhiza kurroa
Kutki (Hindi); Katukarogani (Telugu)
Phyllanthus niruri Jar-amla (Hindi); Nelausiri (Telugu)
Saraca indica Ashoka (Hindi); Asokachettu (Telugu)
Swertia chirayata Chirayata (Hindi); Nilavemyu (Telugu)
Andrographis paniculata Kalmegha (Hindi); Nelavemu (Telugu)
Terminalia arjuna Arjuna (Hindi); Tellamaddi (Telugu)
Valeriana wallichii Tagar (Hindi)
Tinospora cordifolia Gulancha (Hindi); Thippatheega (Telugu)
Asparagus racemosus Shatavar (Hindi); Pillitheegalu (Telugu)
Plumbago zeylanica Chita (Hindi); Chitramulamu (Telugu)
Conuniphora wightii Guggul (Hindi, Telugu)
Boerhaavia diffusa Punarnava, Sant (Hindi, Telugu)
Withania somnifera Ashwagandha (Hindi, Telugu)
Bacopa monnieri Brahmi (Hindi, Telugu)

Top

Utilization of Medicinal Plants

  • The utility of medicinal plants has four major segments:
    • Medicinal plants utilised in indigenous or traditional systems of medicines (ISM) - Ayurveda, Siddha, Unani and Homeopathy systems of medicines.
    • OTC (over the country, non-prescription) items / products involving plant parts, extracts galenicals etc.
    • Essential oils
    • Phyto-pharmaceuticals or plants used in modern systems of medicine.

Medicinal plants used in Traditional Systems of Medicine

  • Traditional medicine is widespread through the world and it comprises of those practices based on beliefs that were in existence, often for hundreds of years, before the development and spread of modern scientific medicines and which are still in use today.
  • As its name implies, it is the part of tradition of each country which employs practices that have been handed down from generation to generation. Its acceptance by a population is largely conditioned by cultural factors and much of traditional medicine, therefore, may not be easily transferable from one culture to another.
  • An important feature of traditional therapy is the preference of practitioner for compound prescriptions over single substance/drug as it is being held that some constituents are effective only in the presence of others.
  • This renders assessment of efficacy and eventually identification of active principles as required in international standards much difficult than for simple preparation.
  • In India, earlier the medicines used in indigenous systems of medicines were generally prepared by the practicing physicians by themselves, but now this practice has been largely replaced by the establishment of organised indigenous drug industries.
  • It is estimated that at present there are more than 1,00,000 licensed registered practitioners of Ayurveda, Siddha, Unani medicine or Homeopathy.
  • As far as the Ayurveda system of medicine is concerned, it does not rule out any substances being used as potential source of medicine.
  • Presently about 1000 single drugs and 8000 compound drug formulations of recognised merit are in vogue.
  • In fact reliable data on availability in different regions of country as well as supply and demand of medicinal plants used in production of indigenous medicines are not available.
  • However, annual herbal drug market has been estimated around 2200 crores and is expected to reach up to 4000 crores by the year 2000.

Plants-parts, extracts and galenicals

  • The direct utilisation of plant material is not only a feature of ISM in the developing world but also in developed countries like USA, UK, Germany etc., the various herbal formulations are sold on health food shops.
  • Preparation of decoctions, tinctures, galenicals and total extracts of plants also form a part of many pharmacopoeias of the world.
  • The current trend of medicinal plants based drug industry is to procedure standard extracts of plants as raw material.

Essential Oils from plants

  • The essential oil industry was traditionally a cottage industry in India. Since 1947, a number of industrial companies have been established for large scale production of essential oils, oleoresins and perfumes.
  • The essential oil from plants includes Ajowan oil, Eucalyptus oil, Geranium oil, Lavender oil, Palmarosa oil, Patchouli oil, Rose oil, Sandalwood oil, Turpentine oil and Vetiver oil.

Phyto-pharmaceuticals

  • During the past decades, bulk production of plant based drugs has become an important segment of Indian pharmaceutical industry.
  • Some of the phyto-pharmaceuticals which are produced in India at present include
    1. 1.    morphone,
      2.    codeine,
      3.    papaverine (Papaver somniferum),
      4.    quinine,
      5.    quinidine,
      6.    cinchonine and cinchonidine (Cinchona sp., C. calisaya, C. ledgeriana, C. officinais and C.        succirubra);
      7.    hyoscine,
      8.    hyoscyamine (Hyocyamus niger and H. muticus),
      9.    colchicine (Gloriosa superbad, Colchicum luteum and Iphigenia stellata),
      10.  cephaeline and emetin (Cephalis ipacacuanha),
      11.  sennosides A & B (Cassia angustifolia and C. acutifolia),
      12.  reserpine,
      13.  rescinnamine,
      14.  ajmalicine and ajmaline (Rauvolfia serpentina);
      15.  vinblastine and vincristine,
      16.  ajmalicine (raubacine) (Catharanthus roseus);
      17.  guggul lipid (Commiphora wightii);
      18.  taxol (Taxus baccata);
      19.  artemisinin (Artemisai annua) etc.
  • For all these segments of drug, perfumery, flavouring and cosmetic industries, mostly the higher plants are one of the raw materials and comes from the natural resources i.e. forests through forest contractors employing local or tribal people or from the drug farms maintained by the growers of aromatic and medicinal plants.

Top