MALARIA AND PHARMACOGNOSY Syed Hussain Ahmad, Muhmmad Sohail Sajid

MALARIA AND PHARMACOGNOSY

Syed Hussain Ahmad, Muhmmad Sohail Sajid

Department of Parasitology, University of Agriculture Faisalabad

Pharmacognosy, division of science, deals with medicinal drugs extracted from plants or other natural sources. History of herbal medication is as earliest as human civilization. It is considered as the mother of all science. In the past, almost all drugs used were obtained from the plants. History of pharmacognosy is also associated with the history of pharmacy and medicine. The early man sought to improve his woes of illness & injuries by consuming plants. Human being got information about remedial properties of plants, by using extract of those plants which show morphological resemble with their body parts, by observing other animal and human innate discrimination or by accidental discovery during the search of food.

Hippocrates (460-370 BC) considered as the “Father of medicine” for their influence to human physiology and anatomy. He used a large number of plants after collection and identification. Aristotle (384-322 BC) discovered about 500 plants of therapeutic importance with their description and their uses. Theophrastus (370-287 BC) collected and recognized large number of herbal plants and recorded their therapeutic properties. Dioscorides (78 AD) Wrote a book entitled ‘De MateriaMedica”.In his book he defined more than 600 herbal plants with their properties, storage and uses. Pliny de Elder(23-70 AD), a botanist, defined the properties of many plants with their medicinal effect. Galen (131-200 AD), a Greek pharmacist-physician, elaborated the procedures of formulating pharmaceutical preparations having plant and animal extract. With the increase knowledge of phytotharapy, two disciplines were originated. One group focused in identifying the illness known as physician and doctors. The other group is specialized in gathering, formulating and dispensing the drug and became known as pharmacist. In this way, Pharmacognosy developed progressively and formed the foundation of both pharmacy and medicine. On the Other hand, Malaria is a communicable disease and disturbing the social and economic value of human beings throughout the world with 40% prevalence. It causes morbidity about 350-500 million and 1 million mortalities in each year. Pakistan is a part of those countries that have accounted 81% of the estimated mortalities due to malaria. It is a vector borne disease caused by protozoan species of genus Plasmodium (P) including: P. malariae, P. ovale, P. falciparum and P. vivax. Transmission of malaria is accomplished through vector (Anopheles) mosquitoes. The larvae of these mosquitoes can be found on rice fields, grassy channels, bank of rivers, temporary rain pools and marshy places.

Transmission of Plasmodium species is done by the bite of an infected female Anopheles mosquito. About 60–100 anopheles species have ability to transmit malaria in the world. Person to person transmission is common by the bite of mosquitoes. There is no animal reservoir for malaria parasites. It is entirely a human disease. In endemic areas, children under the age of five years and pregnant women are at more risk group than other population. The clinical presentation of malaria depends very much on the pattern and intensity of malaria spread in the area of habitation, which defines the degree of protective acquiredimmunity. Malaria characterized by fever, including chills, headache, myalgia, and malaise. Malaria may be associated with anemia and jaundice. Diagnosis can be done by molecular and serological tests. Currently, the preventive measures include chemoprophylaxis and avoiding mosquito bites. No malaria vaccine is available in market as many of them are under development. Chemoprohylaxis of malaria depends on the travel location, resistance pattern of parasite, age, extent of vector exposure, seasonality and level of transmission and pregnancy. Plant species viz; Oleacapensis, Periplocalinearifolia,Tecleasimplicifolia, M. putterlickioides, Albiziaamara,and Maytenusheterophylla are recognized for treatment of malaria. As Anopheles mosquitoes are nocturnal feeders so malarial transmission mostly arises at night. Mosquito bites can be avoided by wearing clothes that cover most of the body, insect repellant use on exposed skin and by using mosquito bed nets.

Control measures of vector depend on mosquito biology, cost, vector species, epidemiological context, acceptance by populations and vector species. But the best main prevention is to decrease the contact between humans and mosquitoes. People mostly come in contact with mosquito bites due to a combination of humidity, heat, scent and light. Some plant extracts like Lemon eucalyptus oil is one of the most common natural repellents and is used by people since 1940s. In mosquito repellents, eucalyptus has been approved as an effective ingredient by the Center for Disease Control and Prevention. According to a recent study, for three hours more than 95% protection mosquitoes can be achieved by using a misture of 32% lemon eucalyptus oil.

Lavender (vernacular:???? ?????)  The oil and fragrance produced by the crushed lavender flowers can be used as mosquito repellent. A study was conducted on hairless mice found lavender oil to be effective against adult mosquitoes. Lavender has antiseptic, analgesic and antifungal properties. It also has soothing effect on the skin.Lavender can be grown in outdoor as well as indoor garden. To the areas of body that are bite-sensitive apply the oil of crushed flowers. Some lavender drops can also be dropped on a clean cloth and rub on skin. Cinnamon oil (vernacular: ??? ????) is a part of applesauce or oatmeal. A study conducted in Taiwan shows tha cinnamon oil can beused for killing off mosquito eggs.

Thyme oil (vernacular: ????? ??????) a protective agent against mosquitoes, shows 91% protection with 5% concentration. For 60-90 minutes 85% protection is provided by the burning thyme leaves. Soybean oil products like Bite Blocker for Kids (2%) can provide long-lasting protection from mosquitoes. Addition of soybean oil along withlemongrass oil can be used for protection against several mosquito species. Citronella (vernacular: ?????? ) is a common natural essential oil that works against mosquitoes. Citronella candles can offer up to 50% protection. Tea tree oil has anti-inflammatory, antiseptic and antimicrobial qualities. Tea tree oil is also proved to be an effective insect repellent by some recent studies. Geranial is a kind of alcohol those fragrance and also ingredient in many mosquito repellent products. Depending upon species, it gives protection from two to four hours. Neem oil can deliver 70% protection for three hours. As it cause skin irascibility hence cannot be considered suitable as a topical repellant. For making mosquito repellent add 50 to 100ml of neem oil in water. Precaution for using essential oils is that they should not be directly applied on the skin instead diluted with a carrier oil like almond oil.  The recipe is usually 1 ounce of carrier oil mixed in 3 to 5 drops of essential oil. Following plants in home can used as mosquito repellent, Basil Plant – tulsi – ????, Lavender Plant – ???? ?????, Lemongrass – ????????, Mint – Podina – ??????, Marigold flower – GaindakaPhool – ?????