Aromatic Plants

Introduction

Medicinal plants in traditional systems of medicine and emerging plants of drug and pharmaceutical industries

Introduction

  • The use of plants as medicine is as old an human civilization.
  • The earliest record of use of medicinal plants for prevention of diseased and cure of ailments can be traced in "Rigveda" perhaps the oldest repository o fhumna knowledge having been written between 4,500 and 1600 BC.
  • In the 'Atherveda", which is a later production , the use of plants as drug is more varied and it is the "Ayurveda" which is considered as "Upveda" that the definite properties of drugs and their uses have been given in more details.
  • To the early part of this century, there was a perceptible change from herbal medicines to synthetic and coal-tar products and one time it was thought that the chemical systesis would completely replace the drugs of plant origin.
  • There is no doubt that, with the development of many wonderful drugs of plant origin and phenomenal growth of modern pharmaceutical industry, the pace of growth and popularity of herbal medicine have been considerable affected in recent past, but the indigenous (traditional ) or folk medicines still remain alive as precious cultural heritage in different civilization of the world and herbal medicines continued to cater the medicinal needs of the third world countries which are inhabitated by approximately 80% of the world's population.
  • Moreover, there has been renewed interest in the herbal medicines and apex body like WHO has recognized the potentialities of traditional or folk medicines in the management and self reliance of medicinal care system, and currently encourages, recommends and promotes the inclusion of herbal drugs in "National Health Care Pragrammes" because such drugs are easily available at a price within the reach of a common man and as such are time tested and thus considered to be much safer than the modern synthetic drugs.
  • India, in this regard has unique position in the world, where a number of traditional systems of midicine Ayurveda, Siddha, Unani, Homeopathy are practiced and utilized in the total health care system of the country and all the these systems are predominantly dependent upon medicinal plants.

Medicinal plants used in Traditional or Indigenous systems of medicine

  • Traditional medicine is wide spread through out of the world and it comprises those practices based on beliefs that were inexistence, often for hundreds of years, before the development and spread of modern scientific medicines and which are strill in use to day.
  • As its name implies, "It is the part of tradition of each country of employees 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 once culture to another".
  • An important feature of traditional therapy is the preference of practitioner for compound prescriptions over single substance/drugs 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 more difficult than for simple preparation.
  • In India earlier, the medicines used in indigenous systems of medicines were generally prepared by the practicing by themselves, but now this practice has been largely replaced by the establishment of organized indigenous drug's industry.
  • It is estimated that at present there are more than 46,000 licensed pharmacies in Indian systems of medicine and nearly 400,000 registered practitioners of Ayurveda, Siddha, Unani medicine or Homeopathy. As far as the Ayurveda systems of medicine is concerned, it does not rule out any substances being used as potential source of medicine.
  • Presently about 1,000 single drugs and 8000 compound formulations of recognized 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 has been estimated around 2,000 crores and is expected to reach up to 4,000 crores by the year 2,000.

Herbal Crude Drugs

  • In India most of the medicinal and aromatic plant or crude drugs (roots,Stems,leaves, flowers,seeds,fruit,whole plants etc.) are handled by the traditional herbal crude drugs dealers commonly known as "Pansaris" in the North and "Pachamarunna Kado" in the south, who sell crude drugs under Ayurvedic, Unani or local names.
  • They have go their own traditional suppliers who have been supplying the crude drugs to them since ages.
  • In the market, we do not often get genuine or standardized crude drugs due to one or another reason. In large number of cases botanically different plants are being sold and used for the same Ayurvedic drug in different places.
  • Some times different species of the same genus which are more easily and cheaply available are used in the place of one that has been prescribed in the literature. Further, there are certain well known drugs about which confusion still prevails with regards to their correct identity dur to the fact that descriptions of the plants in Ayurvedic literature are meager and vague.
  • As a result of this confusion, different drugs are being sold in different states under exactly the same name and even the learned physicians (Vaidyas, Kaviraj, and Hakims can not say with certainity which is the authentic specimen meant in the old texts.
  • Some examples may prove this point of view. "Brahmi" a very important drugs in the Ayurvedic Material Medica of India, has been employed as a nervine tonic, useful in insanity and epilepsy from ancient times.
  • The correct identity of this drug is not certain on account of the fact that different plants are sold under the name "Brahmi". In UP, most of the Ayurvedic physicians regard Centella asiatica (Syn. Hydrocotyle asiatica) to be "Brahmi" while physicians of Bengal consider Bacopa monnieri (Syn. Herpestis monniera) as the real Brahmi of Ayurveda. In North Gujarat and Saurastra, the entire species of Hydrocatyle viz. H.Java
  • nica and h.rotundifolia are also used in some part or the other as "Brahmi" or Mandukparni". However, Most of the Physician consider Bacopa monnieri as Brahmi and centella asiatica as "Mandukuparni" being two separate indentity of the drug in Ayurvedic texts.
  • Similarly Chaerophyllum villosum sold in place of Aconitum heterophyllum as "Atis"; Polyalthia Longifolia and Shorea robusta inplace of Saraca asoca as "Ashoka", and different crude drugs are available in the market under one vermacular names of "Nag Keshar"-e.g Flowe buds of Mesua ferrea, Ochrocarpus, logifolius, Callophyllums inophyllem, Cinnamomum tamala and Dellenia Pentugyna etc.

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Global Importance

  • If we are to discuss the global importance of medicinal plants, it is necessary to defince the term medicinal plant.
  • In the broadest definition of medicinal plants-It includes all higher plants that have been alleged to have medicineal properties i.e effects that relate to health or which have been proven to be useful as drugs by western standards of that which contain constituents that are used as drugs.

    1.    Complicating the matter of identifying all such plants is that, there are no readily available souces of        information, i.e, the information is found scattered through out the world- in classical old leteratures,        books om medical botany, in ethnbo-medico-botanical survey reports for specific geographic regions        and or for different in various herbiaria. In variety of reviews articles and in other sources.
    2.    Secrets locked in minds of indigenous peoples, traditional healers etc. are less likely to discovered.

Importance of medicinal plants

  • Finally how does one measures "Importance" of medicinal plants. It may be possible in two ways

    1.    It is possible to document in many ways, that medicinal plants and their active principles are able to        alleviate or cure human suffering and illness.
    2.    Another, way is to measure the monetary value of the cost of the plants entering into global commerce,        but data are available only for plants that are entering into commerce on a major scale i.e. hundereds or        thousands of tons per year.
    3.    On global basis, it appears that only consolidated source of information in the monetary values of        medicinal plant entering into global commerce is that provided by the International Trade Centre        (UNCTAD/GATT). The most recent compilation of data from this agency involving medicinal placts and        their derivatives was published in 1982. However this information must be considered as grossly        incomplete. Major data on export/import of medicinal plants involve West Germany, Singapore and Hong        Kong. However, these countries produce little, medicinal plants.
    4.    Other producing countries often do not report details of specific plants but only report figures for "Seeds",        "Roots", "Medicinal Plnats" etc. However, a publication. Export potential of selected Medicinal plants and        their derivatives has been brought out in India by CHEMEXCIL India.

Prospects of cultivation

  • Most of the medicinal plants extensively used in traditional systems of medicines are obtained from wild sources leading to dwindling of populations of numerous plants. Some of the important medicinal plants have become threatened or endangered in their natural habitats.
  • Rauvolfia serpentina (Sarpgandha) a very important medicinal plants of widespread distribution is today no where in abundance because of heavy exploitation of the wild strain during the last 60 years.
  • Aconitum heterophyllum (Atish), A.deinorrhizum, Cochicum lutium (Chlchicine plant) Gentiana Kurroa widely distributed in western Himalayan have become endangered species. Commiphora wightii (Guggul) distributed in Gujarat and Rajasthan has been much exploited for gum resin.
  • Podophyllum hexandrum (Babd kakari) and Nardostachys grandiflora (Jatasmansi) now rarely occur in Himalay.
  • Populations of Coptis teeta of Mismee hills (Arunachal Pradesh) have seriously dwindled due to excessive trade from natural population. The increasing demands of the pharmaceutical industry have created problem of supply and one of the major difficulties being experienced by the Indian systems of medicine is that of obtaining sufficient qualtities of medicinal plants for the manufacture of genuine medicines.
  • In the absence of standards for crude drugs adulteration and substitution have become rampant.
  • To correct this situation, measures are needed to promote the cultivation of medicinal plants, to improve method of collection, to ensure effective quality control and to regulate commerce so as to protect the producer and the consumer.
  • In our country, there are only few herbal drugs under large scale cultivation that are used in indigenous systems of medicines as well as in modern systems of medicines. Theres are Isabgol (Psyllium), Ahiphen (Poppy) and Svarnpatri (Senna).
  • There are other that are cultivated on a very small scale exclusively used in indigenous systems of medicine: Kali mirchi (Pepper Nigrum), Haldi (Curcuma longa), Adraja (Zingiber officinalis), Dhaniya (Coriandrrum); Sanuf (Foeniculum), Ajawayn (Trachyspernum) etc. Cultivation of medicinal plants permits production of uniform quality raw material whose properties are standardized and from which the crude drugs can be obtained unadulterated.

Collection from wild Versus cultivation of medicinal plants

 
Collection
Cultivation
Availablity
Decreasing
Increasing
Fluctuation of supply
Unstable
More controlled and quality
Quality control
Poor
High
Botanical indentification
Sometimes not reliable
Not questionable
Genetic improvemt
No
Yes
Agronomic manipulation No Yes
Post harvest handling Poor Usually good
Adulteration Likely Relatively safe

  • One of the major difficulties for undertaking medicinal plants in large scale is the lack of scientific and appropriate agro technology for different climatic zones.
  • Experimental cultivation has been carried out in several places, but the recommended commercial practices had been neither worked out nor tested on an industrial scale. Moreover, even if the cultivation is likely to yield economic returns, the dominant sector or cultivators in the country are conservative and are reluctant to abandon their time tested crops and turn to medicinal crops.
  • In the view of the present status of medicinal plants used in medicines, there is a need to pay special attention on the cultivation of medicinal plants which are extensively used by industry; which have become endangered/threatened; on which significant research lands have been obtained and are emerging in world pharmaceutical industry; which are being imported and have exported potential.

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Products from Aromatic crops & their uses

Aromatic Crops

Distillation Water

    1. Recycle for Distillation

    2. Irritation

    3. Spraying on Crops

    4. Extraction of dissolved Oil components by Cohobation, Poroplast technique etc.

Suggested Uses:

    4. In Naturopathy

    5. Aromatheraphy etc.

    6. For bathing

    7. Herbal Teas etc.

    8. Making of perfumed Waters

Essential Oil (Steam Distillation)

Fractional Distillation

Terpeneless Essential Oils, Aroma chemicals, Residual Essential Oils

    1. Fragrance Industry

    2. Flavour Industry

    3. Pharmaceutial Industry

    4. Other specialised used

Distilled Waste

    1. Manure after composting

    2. Mulching in crops

    3. Fuel for Distillation Unit

    4. Fodder for Domestic Animals

    5. Manufacture of paper

    6. Packing materials Manufacturing

Suggested Uses:

    7. In Biogas Plant

    8. Vermiculture

    9. Mushroom culture

    10. Agarbatti Industry

    11. Extraction of specialized products of pectin from citru--rinds

    12. Extraction of remaining oil components by Acid Hydrolysis

    13. Blending with Fertilizers

    14. In Insect repellin products

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Emerging medicinal plants for drugs and pharmaceutical industries

  • The role of plants as a raw materials for isolation and characterization of new drugs molecules for cure or prevention of most dreaded diseases like cancer and AIDS, ahs created-resugence of interest in them, all over the world.
  • A recent study carried out indicates that about 60% of the anti-tumour or anti-infective agents that are commercially available or at the advanced stages of clinical trials are of natural origin.
  • At present, there are about 125-130 clinically useful prescription drugs derived from about 100 species of higher plants. It has also been estimated that about 5000 species of higher plants worldwide have been studied in some details as possible source of new drugs.
  • A programme for the screening of plant extracts for a wide range of biological activities is in progress at Central Drug Research Institute. Lucknow (India) since last 25 years. So far more that 3,300 plant materials have been screened for various biological activities.
  • Realizing, the importance of the plants in the druf discovery, the bioprespection of the plant species is in progress in many laboratories throughout the world, for the discovery of new pharmaceuticals for the health problems such as drug resistant infectious diseases, diabetes, asthma, arthristis and neurological and psychiatric disordes.
  • The satisfactory cure or means of management for many of such diseases are not yet available in medical sciences.

Medicinal plants and phytopharmaceuticals

  • The World Pharmaceuticals Industry is unique, extremely competitive and highly research based. It is characterized by some very special and striking features like high rate of obsolescence of drug and technologies; requirements of high quality of products;
  • Good manufacturing practices(GMP), Good Labaratory praces (GLP), environmental and regulatory requirements etc. The pharmaceutical research on a established parameters is a complex, multidisciplinary and time consuming activity. The current estimate indicates that more that 12 years of research efforts from discovery to marketing with average cost of about 250 US$ are required for a drug molecule to be used as therapeutic agent.
  • During the past decades, bulk production of placnt based has become an important segment of India Pharmaceutical industry.
  • Some of the phytopharmaceuticals whichare produced in India at present include: morphine, codeine, papaverine (Papaver somniferum), Quinine, Quinidine, Cinchonine and Cinchonidine (Chichona spp. Viz: C.calisaya, C.ledgeriana,C.officinalis and C.succirubra): Hyoscine and Hyoscyamine ((Hyoscyamus niger and H.muticus); Colchine (Gloriso superba, Colchicum luteum and Iphigenia stellata): Cephaeline and emetin (Cephalis ipecacuanha): Sennoside A&B (Cassia angustifolia and C. acutifolia): Rescephine, Rescinnamine, Ajmaline and Ajamalicine (Rauvolfia serpentina): Vinblastine and vincristine, ajalmalcine, raubacine (Catharanthus roseus):Guggal-lipid (Commiphora wightii), Taxol (Taxus baccata); Artemisinin(Artemisia annua) etc.
  • In the present time, Pharmaceutical and chemical sciences have greatly contributed in the enhancement of the utility of medicinal plants.
  • Selected medicinal plants have been subjected to rigorous chemical analysis and the bioactive compounds have been isolated and variously evaluated.
  • As a result, new drugs have been discovered and new applications have been found for the compounds/medicines that were already in use.
  • Over the years, there have been four principal routes bywhich have led to new therpeutic agents.

    1.    Chemical constituents isolated from the plants are directly used as therapeutic agents Such as        digitaxin, strophanhin, morphine and atropine etc. which still unsurpassed in theie respective filed.
    2.    Plant constituents which are used as starting material for the synthesis of useful drugs. For example        adrenal cortex and other steroid harmones are generally synthesized from plant steroidal sapagenins.
    3.    Natural products which serve as models for pharmacologically active compounds in the field of drug        synthesis.Frequently, the side effects of a natural product often prevent its use in medicine and resolved        only by preparation of synthetic derivative for example cocain which led to the development of modern        local anaesthetics; modification of colchicines and of podophyllotoxin to obtain anti tumour preparation.
    4.    The plant constituents which demostrate a mode of action which is then copied as in muscle relaxants        from curare

  • In recent years, there has been use of plant constituents as research chemical particularly in the areas of molecular biology. More that 50 anti-cancer drugs are not marketed because of the side effects but they are widely used in research.
  • One of the major criterion for selection of the plant for discovery of new lead molecules is the utilization of available knowledge in coded or un coded from in traditional or indigenous systems or medicines, including folk or tribal medicines. The past experiences in the areas of drug discovery have proved that the success rates are very high with such plants and they provide a fertile hunting ground for search of new therapeutic agents.
  • In this context, the development of new drugs, viz Reserpine and related alkaloids for treatment of essential hypertension and in certain neuro-psychiatric disorders from Rauvolfia serpentina (Serpengandha); Guggulipid - for lowering of cholesterol from Commiphora wightii Guggul); Forskolin (Coleonol) as anlihypertensive agents from Coleus forskohlii; Bacosides - for memory enhancer from Bacopa monnieri (Brohmi); are some of interesting example of how obervation is recorded in ancient medical text of Ayurveda or fold medicine, when investigated by modern scientific method led to the successful development of new drugs and also provided a lead compound for further modifications.

Some traditional Medicinal Plants on whcih Significant Research Leads have been obtained and have yielded clinically useful drugs

Species
Common names
Drugs
Action / Clinical Use
1. Acorus calamus Vacha Asarone Tranquilizer
2. Adhatoda vasica Vasa Vasicine (Pegarine) Oxytocic
3. Andrographis paniculata Kalmegh Andrographolide; Neo-andrographolide Bacillary dysentery
4. Asparagus racemosus Satawar Sapogenin glycosides Anti-oxytocic, anti-ulcerogenic, burns and wound healing
5. Azadirachto indica Neem Azadirachtin oil Insecticide, antifertility Antidiabetic
6. Bacopa monnieri Brahmi Azadirachtin oil Antianxiety agent, Improve intellect, Adaptogenc
7. Carica papaya Papaya Chymopapain Proteolytic, mucolytic
8. Centella asiatica Brahmi Asiaticoside Vulenerary Wound healing
9. Cissampelos pareira Patha Cissmpeline Skeletal muscle relaxant
10. Coscinium fenestratum Daruhaldi Alkalods (Berberine) Cholera and gastroentiritis
11. Curcuma longa Haldi Curceemin Choleretic
12. Gloriosa superba Kalihari Colchicine, Thio- Odema
13. Gossypium spp. Kapa, cotton Gossypol colchicoside Male contraceptive
14. Mappia foetida Chaneru Camptothecein Anticancer
15. Mucuna pruriens Kewanchh L-dopa Antiparkinsonism
16. Picrorhiza Kurroa Kutki Glycosides Antihepatotoxic
17. Phyllanthus amarus Bhumyamlki Lingnans Antihepatotoxic (Hepatitis B-virus)
18. Silybum marianum   Silmarin Antihepatotoxic
19. Taxus bacccata Talishpatra Taxol Anticancer
20. Tephrasia purpurea Sarpunkha Flavonoids, alkaloids Viral hepatitis
21. Urginia indica Indian squill Scillarin A & B Cardiotonic
22. valeriana wallichii Tagar Valeopotrates Sedative

  • Besides this the plant species viz: Canarium euphyllum, C.manii (Collected from Andman forests): Paeonia obovato (Collected from western ghats); are found to be very active against rhematoid arthritis and inflammation.

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