Artemisia annua: The anti-malarial plant

Boswellia papyrifera  (Frankincense)

Boswellia sacra (Synonym: Boswellia carteri)  

Herbal Medicines for Diabetes mellitus

Distillate Waters

Eucalyptus: The Air Purifier

Moringa tree    

Myrrh (Commiphora myrrha)    

Neem Tree (Azadirachta indica)         

Opoponax (Commiphora guidotti)     

Rosemary for Health and Beauty    

Tinctures

Using Aroma to Combat Stress

Using Aroma to Fight Infection

2.Artemisia annua: The anti-malarial plant Comes to Ethiopia

Artemisia annua L. (also known as sweet wormwood) is an aromatic annual herb traditionally grown in China as a medicinal plant. Recent research has brought this plant into the limelight because of the discovery that it yields a compound known as artemisinin, that exhibits   anti-malarial properties. Many countries have therefore approved use of artemisinin and its derivatives to treat malaria.
A. annua is relatively easy to grow and very high biomass yields can be obtained in 5-6 month period.  This plant was first successfully introduced by the German NGO Anamed (Action for Natural Medicine) on the highlands of Chencha in the Gamo Gofa Region of Ethiopia. It has then been introduced in other parts of the country.  Anamed has also shown that taking the herb in the form of tea cures patients of malaria, with a cure rate of 90%. In our laboratory, we have shown by chemical analysis that the leaves of the cultivar of Artemisia that has been introduced in Ethiopia contain significant amount of artemisinin.

According to www.anamed.org, one liter of boiling water is poured onto 5 g dried leaves and allowed to brew for 10 to 15 minutes. This tea is then drunk by the malaria patient during the course of the day. Repeat this for 5-7 or so days to bring the total to 25-35 g of tea leaves. This experiment has been done successfully in Uganda, the DRC and Tanzania. This tea has also been found to be useful for the following conditions:

• Artemisia tea strengthens the immune system of AIDS patients.
• It treats haemorrhoids, internally as tea and externally as ointment.
• Eye infections, artemisia tea internally and finely filtered, as an eye bath.
• Bronchitis, as tea and inhalation.
• Skin complaints, as ointment.
• Digestion problems, as tea etc.

Further uses include, the vapour against colds and coughs, and chewing the leaves to treat Candida infection in the mouth.

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3. Boswellia papyrifera  (Frankincense)
Frankincense or olibanum is the name given to hardened resinous exudate derived from different species of Boswellia. The principal frankincense producing species include B. papyrifera (Del.) Hochst, B. neglecta S. Moore and B. rivae Engl. occurring in Ethiopia, B. frereana Birdw. and B. sacra Flueck. (Synonym: B. carteri Birdw.) in Somalia and Arabia, and B. serrata (salai guggal) in India. This short article deals mainly with B. papyrifera. For B. rivae see: http://portal.ics.trieste.it/MAPs/EssentialOils_Oil.aspx?id=13

About the tree: B. payrifera is a deciduous tree that grows up to 12 m. It is known to occur in North Ethiopia, Eritrea, Sudan and in some parts of West Africa (Vollesen, 1989).Its bark is white to brown and peels off in large flakes. The wood is light and soft, it is used for fencing and to make household furniture. When the trunk of the tree is tapped, a white fluid oozes out, which gradually dries (2-3 weeks) to yield the high valued frankincense resin. The tree is tapped at regular intervals throughout the dry season (in Ethiopia September to June). A tree yields on the average 2-3 kg of resin per year. After 4-5 years of tapping the tree needs to rest for 3-5 years [Kindeya, 2003]. There is hardly any cultivation of this plant. It is wild and certainly organic.

The resin: Etan is the common name in Ethiopia. In commercial circles it is referred to as Tigray or Eritrean or church Type. It is widely used as incense and to some extent for chewing in the surrounding countries including the Middle East and in many churches worldwide. The absolute, which is obtained by macerating the resin with ethanol at room temperature and the oil obtained by steam distillation find applications in traditional medicine, perfumes, aromatherapy, pharmaceuticals, as flavor in the food and beverage industries, for making adhesives, chewing gum etc.  Ethiopia and Sudan are the biggest exporters of B. papyrifera resin.  Unofficial trade among producing countries makes it difficult to estimate volume of export. The annual volume of export from Ethiopia varies between 1000 and 2000 tons [Coppen 1995; Kindeya 2003].

Conservation: Several factors have been cited by Kindeya (2003) for the decline in the population of B. papyrifera. There is increasing population pressure in the areas where B. papyrifera occurs resulting in conversion of Boswellia woodlands to agricultural lands. Unregulated grazing has also damaged natural regeneration since its seeds and seedling are preferred by livestock and wild life. Improper incense tapping practices such as over-tapping, use of inappropriate tapping methods by unskilled labourers etc also contribute to decline of the population of this plant, thus making it one of the threatened species of the region. More efforts to rehabilitate B. papyrifera has been recommended such as closure of degraded sites from livestock grazing.  (Kindeya, 2003).

Ethno-botanical information: Incense is burnt as insect repellent and also chewed by local people to quench thirst during hot days. Frankincense was used as a stimulant and to treat wounds and leprosy in China (Tucker, 1986). Frankincense is used in Arab homes to perfume clothes and purify the atmosphere. It is used in traditional festivities such as weddings and religious celebrations. It probably was one of the ingredients used by the ancient Egyptians for embalming.

Pharmacological studies: There are only limited pharmacological studies on the essential oil or extracts of B. papyrifera. The essential oil exhibited good activity against fungal strains with MIC values of 6 g/ml (Camrada et al., 2007). Since this resin is a good source of incensole and its derivatives, more work needs to be done on the pharmacological properties including anticancer studies.

 Chemical constituents: Although the gum resin of B. papyrifera coming from Ethiopia, Sudan and E. Africa is believed to be the main source of frankincense of antiquity   (Tucker, 1986), there was until recently a great deal of confusion in the literature regarding the chemical analysis of its resin as well as of the essential oil derived from it by steam or hydro distillation. This was mainly due to the fact that analyses were done on commercial samples without establishing the proper botanical identity of the true source of the resin. This led to confusion because resins of several Boswellia species are traded as frankincense or olibanum in the world market such as the resins originating from B. sacra (Syn. B. carteri of Somalia and Oman), B. frereana (Somalia), B. papyrifera (Ethiopia and Sudan) and B. rivae and B. neglecta (Ethiopia) and B. serata (India).

The works of Dekebo et al (1999, 2002), Basar (2001, 2005) and Hamm et al. (2005) have clarified the distinction between B.sacra and B. payrifera. Dekebo et al. (1999) working on olibanum obtained from an identified plant established that the essential oil of B. papyrifera resin is characterized by the presence of octyl acetate (56%), octanol (8%) and smaller amounts of monoterpenes namely alpha-pinene, limonenene and linalool and only traces of sesquiterpenes.

The above results are significant because previously some studies on essential oil of olibanum in which octyl acetate was the major component were erroneously reported as coming from B. carteri (Abdel Wahab et al., 1987), Vernin et al. (1990) and  Basar et al. (2001). The two species are further distinguished by the presence of incensole and incensole actetate only in B. payrifera (Hamm et al., 2005), thus making these two compounds as additional biomarkers for B. papyrifera. On the other hand B. frereana,  is rich in the monoterepens, alpha-thujene and alpha-pinene, poor in sesquiterepnes.  

References
Abdel-Wahab, S. M., Aboutabl, E. A., El-Zalabani, S. M., Fouad, H. A., De Pooter, H. L., and El-Fallaha, B. (1987). The Essential Oil of Olibanum. Planta Med.  382-384.
Basar, S., Koch, A. and Koenig, W.A. (2001). A Verticillane-type Diterpene from Boswellia carteri Essential Oil. Flavour Fragr. J. 16, 315-318.
Basar, S. (Advisor Prof. W.A. Koenig) (2005). Phytochemical Investigations on Boswellia species, PhD Dissertation, University of Hamburg, Germany. (Full text available on the Internet).
Camarda, L.et al. (2007), Chemical Composition and Antimicrobial Activity of Some Oleogum Resin Essential Oils from Boswellia spp (Burseraceae), Annali di Chimica, 837-844.
Coppen, J.J.W. (1995). Flavours and fragrances of plant origin, Non-Wood Forest Products, 1, FAO, Rome.
Dekebo, A., Zewedu, M., Dagne, E. (1999) Volatile oils of frankincense from Boswellia papyrifera. Bull. Chem. Soc. Ethiop. 13: 93-96.
Dekebo, A. (Advisor E. Dagne) (2002). Chemical Studies of the Resins of Some Boswellia and Commiphora Species, PhD Dissertation, Addis Ababa University, Ethiopia.         
Kindeya, G.H. (2003). Ecology and Management of Boswellia  papyrifera (Del.) Hochst. Dry Forest in Tigray, Northern Ethiopia. PhD Thesis, Culvillier Verlag, Gottingen, Germany.       
Mesele, A. (Advisor, E. Dagne, 2007).  MSc Thesis, Chemistry Department, Addis Ababa University, Ethiopia.
Tucker, A.O (1986) Frankincense and Myrrh, Economic Botany, 40: 425-433.
Vernin, G., et al. (1990). GC-MS Data Bank Analysis of the Essential Oils from B. frereana and Boswellia carteri Bird. Dev. Food Sci. ,24:511-542.

For the accepted botanical naming for B. sacra (Syn. B. carteri) see http://zipcodezoo.com/Plants/B/Boswellia_sacra/

See also:
http://portal.ics.trieste.it/MAPs/MedicinalPlants_Plant.aspx?id=584
and http://portal.ics.trieste.it/MAPs/EssentialOils_Oil.aspx?id=13

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4. Boswellia sacra Flueck. (Synonym: Boswellia carteri Birdw.)

Common Names: In Somali Mohor (tree), Beyo (resin). In Arabic Mogar (tree), Sheehaz (resin), in English Arabian Frankincense.
Geographical distribution: There are two geographic origins where this plant occurs. For many years botanists considered the frankincense plant occurring in Arabia (i.e. South Yemen and Dhofar region of Oman) as the distinct species B. sacra Flueck., while considering the similar plant found at the tip of the Horn of Africa in North Somalia as a different species named as B. carteri Birdw. These taxa are now lumped together as one taxon, B. sacra (www.ipni.org/index.html).

Conservation: B. sacra tree could be 1.5 – 8 m tall, branching from the base or with a distinct trunk, bark pale brown with some outer flaking papery layers.  B. sacra occurs in Acacia-Commiphora woodland at altitudes not exceeding 1200 m, usually in rocky slopes and gullies in particular on limestone boulders. The areas where these trees are found are arid and mostly inaccessible making conservation work quite a difficult undertaking.  
The resin: B. sacra resin is barely translucent, yellowish or brownish in colour, partly brittle, softens when chewed and tastes bitter but aromatic. It has characteristic sweet balsamic aroma and it smells pleasant when placed on hot charcoal.

There are six most common Boswellia species whose resins are widely traded and these are:-

Extractability of dried material: Table 1 shows extractability data of gum-resins of 4 frankincense species with four solvents

Very useful information about nature of a given gum-resin can be obtained by determining its solubility in different solvents. The procedure we followed was as follows: In each case 500 mg of the frankincense was powdered and extracted with the solvent by using sonic bath for 20 min, filtered and then solvent removed using rotary evaporator. In the case of extraction with water the filtered extract was frozen and dried by freeze drier.  The residue was weighed giving soluble fraction yield in mg and % as shown in the Table above. As can be easily deduced the results are indeed most interesting and have far reaching implications for determining identity and quality of a given resin. There is thus clear cut distinction between Meydi and Beyo. The Meydi sample is almost totally soluble in hexane (90-95%), where as the solubility of Beyo in hexane is much lower 45-50%. 

It is interesting to note that Anon as early as in 1941 came to the above conclusion as quoted below: “The samples of Mohor contained considerable amts. of water soluble gum, whereas the Maidi samples were almost free from gum. Judging from the analyses, the difference in the composition of the exudations from the 2 species of trees is such that only that from B. carteri can be truly designated as a gum resin or gum oleoresin; the product of B. frereana, being practically free from gum, would be classified as an oleoresin of the elemi type, and not an incense gum.” (Anon, 1941).

It is a pity that subsequent workers did not pay attention to the findings of this paper, which if followed would have helped to avoid the unnecessary confusions that permeate over the years through the literature. This simple solubility test could also be used as a quick test to distinguish Beyo gum resin (B. sacra) from Meydi resin (B. frereana). Guenther (1943) also stated B. sacra (syn B. carteri) gum-resin to be “about 75% soluble in alcohol”. Table 1 above clearly shows that Meydi is essentially a pure resin while the other types of frankincense can be considered as gum-resin.  On the other hand myrrh can be designated as gum-resin because it is partly soluble in hexane (15%) and also in water (60%) (see AAMPS Profile Monograph on Myrrh).

The study of the chemistry of frankincense has attracted over the years the interest of several chemistry research groups in different parts of the world. The main limitations of many of these reports is the fact that many workers did not pay much attention to the precise botanical origin of the resin they studied. This is in part because people worked on resins obtained from trade circles (Cairo, Turkey, Israel, Hamburg etc) rather than on resins collected from properly identified trees.

The trees and resins of each of these frankincense producing species are known in different localities by different names. However in English the resins are all lumped under the general name frankincense or olibanum, although in most cases the geographic origin is given some emphasis.

Abdel-Wahab (1987) working on sample obtained from Cairo, Egypt, and believing it to be B. carteri reported the chemical composition of the essential oil, which contained in addition to several minor mono-terpenes two prominent compounds namely octyl acetate and 1-octanol. However it became very evident from our work (Dekebo et al. 1999) that this profile is typical of B. papyrifera clearly showing that the material these workers investigated was B. papyrifera gum-resin and not B. sacra (syn. B. cateri). Similar problem arose also in the excellent PhD dissertation of Basar (2005), which was conducted under the guidance of the late Professor Koenig of Hamburg University. The dissertation gives a comprehensive account of the resin of B. payrifera although the botanical origin of the resin was erroneously reported to be B. carteri. One should therefore read the dissertation by substituting B. papyrifera in place of B. carteri. Indeed it is in this study that the unique compound verticilla-4(20)-7,11-triene was discovered for the first time as one of the constituents of  B. papyrifera, which also contains incensole, incensole acetate, n-octanol and octyl acetate. This group of compounds now enables one to distinguish with ease B. papyrifera not only from B. sacra (syn B. carteri) but also from all other Boswellia spp. Our analyses by GC (Fig. 2) shown below on the essential oils of samples obtained from these three species indicate striking differences. 

Fig. 2: Gas chromatographic profile of essential oils of three frankincense species A: B. sacra or Beyo  (Somalia) B : B. frereana or Meydi (Somalia)  C. B. papyrifera (Ethiopia).

Similar conclusions can also be arrived at using TLC fingerprints

The TLC above is that of the hexane extracts of gum-resins of Boswellia species. BK (unknown origin), BP (B. papyrifera), BC (B. sacra) and BF (B. frereana). The yellow coloured spots in BP are due to the diterpenes  incensole (lower spot) and incensole acetate (upper spot), compounds that are unique markers for B. papyrifera that aid in singling out this species from all other Boswellia species. As already described above  1-octanol and octyl acetate are also unique constituents of B. papyrifera. 

            Medicinal uses and biological activities  according to literature: We can now confidently state that several biological evaluation reports in the literature on so called B. carteri resins may not be from trees of this species. For instance in the recent paper, by Akihisa et al. over 15 boswellic acids were isolated along with incensole and incensole acetate from gum-resin supplied to them by an American Co. Scents of Earth.  The workers were led to believe that the gum-resin was derived from B. carteri trees.and that the compounds tpossess strong anticancer and cytotoxic properties. However it is now evident that incensole and incensole acetate are unique markers present only in B. papyrifera originating from Ethiopia and are not present in authentic B. sacra (syn B. carteri) gum-resins. Hence the conclusions of the above important paper may be valid for B. papyrifera gum-resin and not for B. sacra (Syn  B. carteri).  Boswelllic acids are known to possess marked anti inflammatory properties (Safayhi et al., 1997) and are useful in treating patients with rheumatoid arthritis, chronic colitis, bronchial asthma etc.

C: References
Abdel-Wahab, S. M., Aboutabl, E. A., El-Zalabani, S. M., Fouad, H. A., De Pooter, H. L., and El-Fallaha, B. (1987).The Essential Oil of Olibanum. Planta Med. 53, 382-384.
Akihisa, T. et al. (2006). Cancer chemopreventice activities of the triterpene acids from resin of Boswellia carteri. Biol. Pharm. Bull., 29, 1976-1979.
Anon (1941). Incense Gums from British Somaliland. Bulletin of the Imperial Institute, London 39, 99-104.
Basar, S. (2005).  Phytochemical investigations on Boswellia species, PhD Dissertation, Hamburg University.
Birdwood, G. (1870). On the genus Boswellia, with description and figures of three new species. Trans. Linn. Soc. Lond. 27: 111-148.
Dekebo, A., Zewdu, M., and Dagne, E. (1999). Volatile Oils of Frankincense from Boswellia papyrifera. Bull.Chem.Soc.Ethiop. 13, 93-96.
Flueckiger, F.A. (1864). Ueber den Weihrauchbaum. Schweiz. Wochenschr. Parm. 2 (19, 20).
Guenther, E. S (1943). Characteristics and Uses of oil of Olibanum. American Perfumer and Essential Oil Review 45, 41-43.
Safayhi, H., Rall, B., Sailer, E. R., and Ammon, H. P. (1997), Inhibition by Boswellic acids of Human Leukocyte Elastase. J. Pharmacol. Experimental Therapeutics 281, 460-463.
Thulin, M. and Warfa, A.M. (1987). The frankincense trees (Boswellia spp., Burseraceae) of northern Somalia and southern Arabia. Kew Bulletin, 42, 487-500.
For correct naming of B. sacra see: http://www.kew.org/ceb/sepasal/bsacra.htm

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5. Herbal Medicines for Diabetes mellitus

Diabetes is a disorder in which people suffering from it are not able to produce or properly use insulin in the body. Without insulin it is not possible for the human body to utilize glucose properly, thus leading to high glucose levels in the blood. There are two types of diabetes known as Type 1, insulin-dependent diabetes mellitus (IDDM) and Type 2, noninsulin-dependent diabetes mellitus (NIDDM). Type 1 patients are not capable of producing insulin and should therefore take daily insulin injection to stay alive. Most diabetes patients are in Type 2 category, in which the body does not produce enough insulin or is not properly using insulin. In this case drugs and natural products that aid in the release of insulin alleviate the condition of the patient by lowering the level of blood glucose.

Although Diabetes is one of those diseases for which there is no cure, there is now ample scientific evidence that has established beyond doubt that some natural products can be used to control Type 2 diabetes mellitus just as well as the modern drugs. Some of the natural medicines enjoying long indigenous use are presented below.

Garlic or Allium sativum and Onion or Allium cepa: Regular use of these two food items lowers blood sugar by stimulating insulin secretion in the pancreas.

Abish (Amharic), Fenugreek or Trigonella foenum-graecum: The seeds of this plant are traditionally used in many cultures for diabetes care. This is now fully substantiated by scientific research.

Zeitun (Amharic) or Psidium guajava: The water extract of the leaves of this plant lowers blood glucose indicating that it can be used for this purpose in the form of tea.

Homer (Amharic) or Tamarind or Tamarindus indica: The fruit of this plant, used in Indian traditional medicine against diabetes, has been shown by Indian scientists to have beneficial effects in Type I diabetes mellitus, thus holding hope of new generation of antidiabetic drugs. 

Other antidiabetic natural products: Beans or Phaseolus species; Peanut or Arachis hypogaea; Black Tea or Camellia sinensis; Ginseng or Panax ginseng; Black seed or Tikur Azmud or Nigella sativa; Moringa stenopetala or Shiferaw; Aloe vera  etc.

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6. Distillate Waters or Hydrosols

The essential oil is the precious product of steam distillation and is mainly made up of volatile organic compounds most of which belong to the group of natural products known as terpenoids. Distillate Water is a by-product of steam distillation. It is also known by at least four other names: hydrosol, hydrolate, aromatic or floral water. During steam distillation of aromatic plants, the steam that comes out of the boiler carries essential oil molecules and lots of water vapour. When these are condensed they form two phases, with the lighter essential oil as the upper layer and the much larger lower phase containing the distillate water or hydrosol.

Hydrosol is derived from the Latin words hydro and sol, meaning "water solution." Hydrosols usually have strong aroma because they contain small amounts of essential oil and other water soluble molecules. The distillate water that accompanies the essential oil during distillation contains a variety of water-soluble molecules, many of which have medicinal and other biological activities.  The distillate water may not necessarily smell like the essential oil from which it separated. This is because the kinds of compounds that go into the water phase are more polar than those that are in the essential oil. Some polar compounds are known to be beneficial on account of their anti-oxidant activities. Since most distillate waters are not concentrated, they may be used as they are or diluted a bit before use.

One of the most popular distillate waters is that of Eucalyptus, which can be used for a variety of purposes such as antiseptic spray around the home, as toilet water, as body spray, for wound cleansing, for footbath and for hair and skin rinse. Immersing the feet in a bowl containing distillate water of Eucalyptus is one of the best ways of treating tired and sweaty feet. Also try a facial compress after dipping a small towel in aromatic water. Rosemary distillate water is particularly ideal for hair rinse.

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7. Eucalyptus: The Air Purifier

Eucalyptus trees with over 500 species are native to Australia and Tasmania and are mainly used for production of timber, fuel wood, essential oils and as a source of nectar in honey production. In 1895, upon the request of Emperor Menelik II, a French philologist, Mondon-Vidaillet, brought to Ethiopia seeds of several Eucalyptus species. Two species were soon found to be particularly suitable for Ethiopian climatic and soil conditions and these were E. globulus or the "white eucalypt" (Amharic Nech Bahrzaf) suitable for growing on the highlands and E. camaldulensis or the "red eucalypt" (Key Bahrzaf) for the lowlands1. The other species that were later introduced widely in Ethiopia are E. citriodora, E. regnans, E. saligna and E. tereticornis2.

Of all the eucalyptus species, the one that is very popular as medicinal plant is without doubt E. globulus (Blue Gum Eucalyptus). The major compound present in its essential oil, obtained by steam distillation of the leaves and twigs, is 1,8-cineole, which is responsible for its characteristic smell and medicinal properties.  The presence of this compound can be established by gas chromatographic (GC) analysis. The figures below shows GC profiles of two eucalyptus oils, the top for the oil of E. betryoides, with -pinene (Peak 1, 70%) and the bottom for E. globulus with 1,8-cineole (Peak 2, 80%) as major components.

Eucalyptus oil purifies the air by killing bacteria and other disease causing germs. It is known to be antiseptic, deodorant, useful for lung diseases, sore throat, colds and to heal wounds, burns, insect bites etc. If diluted with carrier oil and rubbed on the skin it brings relief from arthritis and rheumatism because it increases blood flow to the area, producing a feeling of warmth. If suffering from flu, there is no better momentary relief than inhaling this oil. This can be done by placing a drop or two of the essential oil on a piece of tissue paper, inserting it in the nose and inhaling. This clears a stuffy nose and a foggy head. Eucalyptus oil should not be taken internally because it is toxic if ingested, and should always be kept out of reach of children. 

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9. Myrrh (Commiphora myrrha)

Myrrh is a gum-resin obtained from the trunk of the shrub or thorny three known in botany as Commiphora myrrha (Nees) Engl. Myrrh gum-resin is dark brown in colour with characteristic deep balsamic aroma, not so pleasant but not repulsive either. It also has a unique bitter taste that may also serve as a quick aid to distinguish it from many other related gums and resins.
Myrrh is wild crafted mainly by nomadic people who collect and sell the resin in nearby markets, which is then passed on through a supply chain eventually reaching large enterprises who organize clean up, sorting and grading for eventual export to international traders. Main buyer countries are Germany and France in Europe and India and China in Asia.

Commiphora and Boswellia species occur in semi arid regions and are not cultivated, other than being used to make hedges. They are economically and ecologically important plant species found mainly in Arabia and the horn of Africa particularly in Ethiopia, Somalia and Kenya. Little is written and known about the distribution, potential production, development opportunities and ecological conservation in the vast dry lands of these countries. Unfortunately the areas where these trees are found are arid, mostly inaccessible and are currently conflict prone, thus making conservation work highly challenging.
Strictly speaking genuine myrrh resin, with the typical aroma and characteristic chemical composition, is derived only from C. myrrha. However, in commerce it is not uncommon to have resins of other Commiphora species, which are present as adulterants. This has resulted in reports in the literature of a large number of compounds that are not present in true myrrh. This is because most previous chemical studies reported from myrrh were based on resins from commerce rather than on materials obtained from properly identified trees. Contrary to other resins, myrrh is quite soluble in water. Myrrh when steam distillated yields essential oil. It can also be extracted with organic solvents.

Myrrh has been used since ancient times as medicine and for ceremonial and religious purposes. In ancient times, myrrh was used by the Egyptians for embalming. The European Commission E+ (Blumenthal et al., 2000) approved myrrh for topical treatment of mild inflammations of the oral and pharyngeal mucosa. The British Herbal Pharmacopoeia (1996) indicates myrrh tincture as a mouthwash for gingivitis and ulcers. Myrrh is also an important drug in Chinese Traditional Medicine (Yen, 1992).

In Somalia and Ethiopia, a decoction of myrrh resin is used traditionally to treat stomachache; it is mixed with powdered charcoal to make ink for writing on parchments and burnt in houses and in the bush to chase away snakes. Modern uses include for flavoring foods, drinks and confectionary items, as additive of perfumes, deodorants, shampoos, bath lotions, toilet soaps, toothpastes, mouth washes, air fresheners etc.

Mekonen et al. (2003) showed the petrol extract of myrrh was not toxic to mice at a dose of 0.96g/kg while Rao et al (2001) found myrrh is not toxic to mice at doses of up to 3 g/kg. These results show the high degree of safety if myrrh is taken internally. However this may not be true of resins from other Commiphora species. For instance, the resin of C. erlageriana is known for its toxicity ascribed to unique podophylotoxin type compounds (Dekebo et al., 2002b).

The wound healing and anti-inflammatory properties of myrrh are well known, making it an important component of mouthwashes and toothpastes. For therapeutic use, myrrh is used in tincture form (1 part resin in 5 parts alcohol). A quick mouthwash is typically made by adding 5-10 drops of myrrh tincture to a glass of water. Other herbal ingredients such as clove, peppermint, rosemary or sage may be added. Myrrh tincture can also be applied to sore gums, lips, or mouth tissue up to three times a day and for skin wash or a vaginal douche. Thus a wide array of creative myrrh containing herbal products can be prepared for painful and swollen tissues, tonsillitis, sore throat, for menstrual cramps etc.

 References
Al-Harbi M.M., Qureshi S., Raza M., Ahmed M.M., Afzal M., Shah A.H. (1997). Gastric antiulcer and cytoprotective effect of Commiphora molmol in rats. J Ethnopharmacol., 55:141-50.
Blumenthal, M., Goldberg, A., Brinckmann, J. (2000). Herbal Medicine: Expanded Commission E Monographs, American Botanical Council, Austin, Texas. PP 273-277.
British Herbal Pharmacopoeia (1996). Exeter, U.K. British Herbal Medicine Association, 141.
Dekebo, A., Dagne, E., Sterner, O. (2002a). Furanosesquiterpenes from Commiphora sphaerorocarpa and related adulterants of true myrrh. Fitoterapia, 73: 48-55.
Dekebo, A., Lang, M., Polborn, K., Dagne, E., Steglich, W. (2002b). Four Lignans from Commiphora erlangeriana. J. Nat. Prod., 65: 1252-1257.
Dolara, P., Luceri, C., Ghelardini, C., Monserrat, C., Aiolli, S., Luceri, F., Lodovici, M., Menichetti, S., Romanelli, M. N. (1996). Analgesic effects of myrrh. Nature, 379: 29.
Mekonen, Y., Dekebo, A. , Dagne, E. (2003). Toxicity Study in Mice of Resins of three Commiphora Species. SINET: Ethiop. J. Sci., 26: 151-153.
Qureshi S, Al-Harbi MM, Ahmed MM, Raza M, Giangreco AB, Shah AH (1993). Evaluation of the genotoxic, cytotoxic, and antitumor properties of Commiphora molmol using normal and Ehrlich ascites carcinoma cell-bearing Swiss albino mice. Cancer Chemotherapy and Pharmacology. 33:130-138.
Rao, R.M., Khan, Z.A., Shah, A.H. (2001). Toxicity Studies in Mice of Commiphora molmol Oleo-gum-resin. J. Ethnopharmacol. 76:151-154.
Yen, K.Y. (1992). The Illustrated Chinese material Medica Crude and Prepared. Taipei: SMC Publishing, Inc. 202.

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10. Neem Tree (Azadirachta indica)

This is another wondrous plant, originally from India distinguished by its bark, which is grey-brown, leaves 5 to 8 pairs of leaflets, flowers creamy white, and yellow oval fruits 2 cm long. The neem tree is is introduced in Gode, Ethiopia, where the tree provides shade from the scorching sun. The people call the plant “Yekinin Zaf” (which means the “pill tree”) indicating its medicinal properties. In India it is known for its varied medicinal and other uses. Brushing the teeth with twigs of the plant is believed to be good for the gum. The seeds can be processed to yield the medicinal neem oil which is useful to treat skin conditions such as acne, psoriasis, warts, scabies, ringworm, boils, fungal infection, dandruff etc. If the neem oil is not available, decoction and extract can be prepared from the leaves and twigs of the tree and used for the same purpose as above.

Neem products accelerate wound and bruise healing with reduced scar formation. This is mainly because of the anti-inflammatory properties of the constituents, which also increase blood flow to the bruised area. Many also believe that neem helps to prevent or delay appearance of wrinkles due to its ability to moisturize the skin.

A number of insecticide commercial formulations are on the market based on neem. The fact that neem is non-toxic to humans, pets and livestock add to the popularity of these products. Neem's insecticidal activity is mainly due to the antifeedant properties of its principal constituent known as azadirachtin, a compound that deters insects from feeding. Hence when neem extract is sprayed on crops in the field or on stored grain, the plant material is protected from insects feeding on it, eventually causing death of the insects. Neem is one of the best natural products for crop protection.

Currently India is the leading producer and exporter of neem products such as pharmaceuticals, fertilizers, soaps, anti-fungal creams, toothpaste etc, surpassing an annual turnover of 2 billion USD. This dominance of the neem market by India may not last long, as new competitors are emerging. Recently Nigeria has launched massive neem cultivation and processing projects.

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11. Opoponax (Commiphora guidotti Chiov.)
 
The Plant: The botanical origin of the resin known in commerce as opoponax, also as scented myrrh, bissabol (Hindi), habak hadi (Somali) and abeked (Amharic)  was clarified by Thulin and Claeson (1991) as Commiphora  guidotti, a shrub or tree that grows up to 5 m.

Use: Opoponax is one of the most common medicines of Somali people. It is used to treat stomach complaints in particular diarrhea, to facilitate withdrawal of placenta  and for topical treatment of wounds. Opoponax is mixed with feed and given to cows and buffaloes to improve the quantity and quality of milk they produce. Opoponax is exported to China as well as to Europe because its essential oil and resinoid are used as fixatives in perfumery.

Pharmacological studies: Screening of extracts of ten plants, used in Somali traditional medicine for the treatment of diarrhea, by assessing their ability to inhibit cholera toxin-induced intestinal hypersecretion in mice resulted in opoponax as the most active. Bioassay-guided fractionation of the ethyl acetate extract of the resin resulted in isolation of the sesquiterpene (+)-T-cadinol, which dose-dependently reduced cholera toxin-induced hypersecretion in mice and inhibited electrically induced contractions in the isolated guinea pig ileum (Claeson, 1990). The results explain the traditional use of the resin to cure stomach complaints including diarrhea.

References

Baser, K.H.C., Demirci, B., Dekebo, A., and Dagne, E. 2003. Essential Oils of Some Boswellia Spp., Myrrh and Opoponax. Flavour Frag. J. 18, 153-156.

Claeson, P. 1990. Pharmacognostic Studies on Scented Myrrh With Emphasis on the Biological Activities of the Isolated Sesquiterpene T-Cadinol.  1-46.  PhD Thesis, Uppsala University, Sweden.

Coppen, J.J.W. 1995. Gum, Resins and Latex of Plant Origin. Non-wood Forest Products No. 6, FAO, Rome.

Mekonnen, Y., Dekebo, A. and Dagne, E. (2003). Toxicity Study in Mice of three Commiphora species. Sinet: J. Ethiop. Sci., 26, 151-153.

Thulin, M. and Claeson, P. 1991. The Botanical Origin of Scented Myrrh (Bissabol or Habak Hadi). Economic Botany, 45, 487-494.

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12. Rosemary for Health and Beauty

"There’s rosemary, that’s for remembrance." (Shakespeare in Hamlet)
Rosemary (Rosmarinus officinalis) is a recent introduction to the herbal flora of Ethiopia and its leaves are commonly used as spice when roasting beef or lamb. But there is a lot more to rosemary than using it for this purpose. 
 Rosemary is an evergreen shrub originally from the Mediterranean region but now grown worldwide.  It is prized both as a culinary and healing herb. Many of the current uses of this aromatic plant have been handed down from ancient times. Historically, Greek and Chinese healers used rosemary as a soothing digestive aid and to get relief from intestinal gas. The tea can be prepared from dried rosemary leaves or by adding small amount of its tincture to warm water. Tincture of rosemary is prepared by adding one part of the leaf to 5 parts of 40% alcohol or strong liqueurs such as brandy, rum or gin.

The ancient Greeks believed that this plant could enhance memory, hence Shakespeare’s quote above.  Today, aromatherapists commonly recommend inhaling rosemary oil for sharpening the mind, countering mental fatigue, and nervous exhaustion.

Rosemary oil, obtained by steam distillation of the leaves and flowers, can be inhaled directly, may be added to bath water, or diluted with carrier oil for use in massage. Many believe that massaging with diluted oil of rosemary helps to soothe muscle and arthritic joints. Its antibacterial and antifungal properties are probably why this oil enjoys universal popularity as ingredient of skin and hair care products. As is always the case with pure oils, use pure rosemary oil in drops or after dilution.

During the distillation of rosemary large amount of distillate water, also known as hydrosol, is obtained as a by-product. This distillate water is saturated with a wide array of bioactive compounds making it a truly healing water, which can be used for hair rinse, foot bath, facial cleansing, and even as tonic for digestive troubles. Diluted rosemary oil and the distillate water are highly recommended for scalp treatment since rosemary is known to activate circulation, cleanse follicles and revitalize the area for hair growth. 

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14. Using Aroma to Combat Stress  

Modern living is filled with stress. Stress affects not only our state of mind but may also affect our physical conditions such as causing increase in blood pressure, faster heart rate, headaches, back pain, digestive problems, insomnia, psoriasis, rash, sweaty palm, gastritis, asthma etc. And how do we combat stress? For serious conditions it is of course obvious to consult a physician. But there are a lot of things that we can do on our own. First we should attempt to heal ourselves through proper diet, using herbal teas, exercise etc. It is believed that sipping a cup of herb tea such as that of chamomile aids a great deal.

A lot of people believe that having a pleasant aroma around oneself changes ones mood and state of mind for the better. The aroma in a room can be changed by placing a few drops of essential oil like eucalyptus or lavender in warm water and letting the molecules of the essential oil gradually diffuse throughout the room. Creating a relaxing atmosphere is one of the simplest ways of combating stress.

To feel better, add few drops of aromatic oil during bathing or while in the shower. In fact lavender, the name given by the Romans to one of the most pleasant natural oils, is derived from the Latin “lavare” which means “to wash” because it was used in bath since ancient times. Furthermore when the vapour of lavender is inhaled it aids onset of sleep and thus help one combat insomnia. That is why some people like to place few drops of lavender onto their pillow before going to sleep.

Massaging the body with pressed oil scented with essential oils helps to a great extent in relieving the body from stress. Note here the difference between pressed oil and essential oil. Pressed or fixed oil is obtained by crushing oil bearing seeds followed by pressing. However, essential or aromatic oils are obtained by steam distillation. Pressed oils are non-volatile, while essential oils are volatile and usually have pleasant aroma. For instance almond and sun flower oils are pressed oils while eucalyptus and lavender oils are essential oils. Pressed oils are excellent carrier oils for essential oils because the two are miscible with each other.

We should also pay attention to our feet that carry our entire weight throughout the day. To relax the feet, taking footbath is highly recommended. This is done by dipping the feet in a bowel containing aromatic or distillate water. Alternatively one may use water to which a few drops of essential oil have been added.  Bathing the feet in this manner protects the feet from athlete’s foot, a fungal disease that usually attacks the toes. When rubbed on the temples, peppermint helps alleviate migraine and headache, and oils like geranium, rose and sandalwood are known to ease stress related allergy conditions like asthma, sinus etc.

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