Chapter one introduction 1 Herbs

Дата канвертавання25.04.2016
Памер94.77 Kb.


1.1 Herbs

An herb is a plant that is valued for flavor, scent, medicinal or other qualities other than its food value (John, 2000). They are used in cooking, as medicines, and for spiritual purposes. Herbs have a variety of uses including culinary and medicinal usage. General usage differs between culinary herbs and medicinal herbs (John, 2000). Herbs are “generally recognized as safe” by the Food & Drug Administration (FDA), at least at concentrations commonly found in foods (Kaefer et al, 2008). Medicinal plants continue to provide valuable therapeutic agents, both in modern medicine and in traditional system (Reaven, 1983). The leaves, roots, flowers, seeds, root bark, inner bark (cambium), berries and sometimes the pericarp or other portions of the plant might be considered in medicinal or spiritual use (John, 2000). In the medicinal uses, herbs (plants) contain phytochemicals that have effects on the body (John, 2000).

Until the 20th century, (Sanusi et al, 2008) most medicinal remedies all over the world were obtained from plants. For example, purple forglove was found to be helpful in dropsy, the opium poppy for pain, cough, and diarrhea, and the cinchona bark for fever. With the emergence of chemical and pharmacological methods in the 20th century, it became possible to identify the active ingredients in the plants and study them. Furthermore, once the chemistry was understood, it was possible to synthesize related molecules with more desirable properties. According to (Sodimu et al, 2008), today, the two most effective and widely accepted drugs for the treatment of malaria today emerged through herbal traditional medicine viz: Quinine from the bark of the Peruvian cinchona tree and artemisinin from the Chinese antipyretic Artemisia annua L. Hence, throughout history, the medicinal benefits of herbs are quoted (John, 2000). There may be some effects when consumed in the small levels that typify culinary "spicing", and some herbs are toxic in larger quantities. For instance, some types of herbal extract, such as the extract of St. John's-wort (Hypericum perforatum) or of awa (Piper methysticum) can be used for medical purposes to relieve depression and stress (John, 2000). However, (Milner et al, 2008), large amounts of these herbs may lead to toxic overload that may involve complications, some of a serious nature, and should be used with caution. One herb-like substance, called Shilajit, may actually help a lower blood glucose level which is especially important for those suffering from diabetes.

In comparative terms, (Metuh, 1987) the western idea of medicine and the traditional African conception differ in scope. In the traditional sense, it refers to a wholistic view of well being, while in the western sense, it is strictly limited to bodily therapeutic purposes. Nze in his own comparative analysis of medicine underscores the peculiarity difference, which defines the traditional wholistic perception of medicine (Metuh, 1987).

According to (John, 2000), modern pharmaceuticals had their origins in crude herbal medicines, and to this day, many drugs are still extracted as fractionate/isolate compounds from raw herbs and then purified to meet pharmaceutical standards. Some herbs are used not only for culinary and medicinal purposes, but also for psychoactive and/or recreational purposes; one such herb is cannabis (John, 2000).

However, many herbs and their bioactive components are being investigated for potential disease prevention and treatment at concentrations which may exceed those commonly used in food preparation herbs (Milner et al, 2008). It is therefore imperative to identify any potential safety concerns associated with the use of various dosages which range from doses commonly used for culinary purposes to those used for medicinal purposes since there are often unclear boundaries between the various uses of herbs (Milner et al, 2008).

Other uses of herbs other than medicinal uses are:

Sacred uses:

According to “Chinese herbal medicine” Herbs are used in many religions for example, myrrh (Commiphora myrrha) and frankincense (Boswellia spp) in Christianity, the Nine Herbs Charm in Anglo-Saxon paganism, the Neem tree (Azadirachta indica) by the Tamils, holy basil or tulsi (Ocimum tenuiflorum) in Hinduism, and many Rastafarians consider cannabis (Cannabis sp) to be a holy plant (John, 2000). Siberian Shamans also used herbs for spiritual purposes. Plants may be used to induce spiritual experiences, such as vision quests in some Native American cultures (John, 2000). The Cherokee Native Americans use sage and cedar for spiritual cleansing and smudging.

Uses as pest control:

Herbs are also known amongst gardeners to be useful for pest control. Mint, spearmint, peppermint, and pennyroyal are a few such herbs. These herbs when planted around a house's foundation can help keep unwanted critters away such as flies, mice, ants, fleas, moth and tick amongst others. They are not known to be harmful or dangerous to children or pets, or any of the house's fixtures (John, 2000).

1.2 Objectives of study

Piper methysticum being a plant used for its medical and social purposes (Johnston et al, 2008), may have been of great benefits in human health due to its biochemical, pharmacological, and medical properties. This study, therefore, was undertaken to evaluate the trace – element composition of the leaf extract.



2.1 History of Piper methysticum (Awa)

Piper methysticum is the botanical name of the plant more commonly known as kava. Other common names for kava include ava, awa, inebriating pepper, intoxicating pepper, kava kava, sakau, and yakona. The Piper genus is made up of at least 1000 species, maybe 2000 or more (Pittler et al, 2003).

According to “Psychedelics Encyclopedia”, Piper methysticum is part of the Piperaceae family, more commonly known as the pepper family. Depending on the source, the Piperaceae family itself is made up of between 2500-3500 species and 5-24 genera (Nerurkar et al., 2007). Besides Piper, the other major genus in the family is Peperomia. The botanical name Piper methysticum is derived from Latin and Greek words. Piper is the Latin word for pepper, and methysticum is the Greek word meaning intoxicating. The name Piper methysticum can be translated into English as intoxicating pepper. (Nerurkar et al, 2007).

Figure 1: Piper methysticum leaf (Awa, kawa leaf)

Figure 2: Piper methysticum plant

Scientific Classification of Piper methysticum
Kingdom: Plantae
Division: Magnoliophyta
Class: Magnoliopsida
Order: Piperales
Family: Piperaceae
Genus: Piper
Species: methysticum

According to (Kevin et al, 2005), Piper methysticum is thought to have originated in Oceania, but the exact location is not known. It is also found in the eastern part of Nigeria precisely used by inhabitants of Imo state and Enugu state in cooking. Today, new Awa plants are almost always started by taking cuttings (cloning, striking) off of living plants. When cultivated under the proper conditions, cuttings are fully grown and ready to harvest within 6 years. Most plant attains a height of 6-7 feet, but some may grow as tall as 15-16 feet. (Kevin Cassell et al, 2005).

2.1.1 Chemistry of Awa

According to “Psychedelics Encyclopedia”, in the past, the psychoactive chemicals in kava were not very well known; recent studies have shown that a group of chemicals named kavalactones are the main psychoactive constituents of Piper methysticum. So far, there are 15-25 different kavalactones that have been identified “Psychedelics Encyclopedia”. Each of them have a different effect, and their concentrations vary in different parts of the same plant, and between the same parts of different plants. Different ratios of kavalactones will produce different effects. The leaves, stems, and roots all contain psychoactive material. The psychoactive effect of ingesting either the leaves, stems, or root is similar but most people find the root most potent (Psychedelics Encyclopedia).

Awa (kava, Piper methysticum) is a plant with medicinal and social uses (Johnston et al, 2006). A relaxing beverage is made from the roots and stump of this plant on islands where it grows throughout the tropical Pacific (Johnston et al, 2006). Cultivars of the plant were intentionally transported to Hawai‘i by Polynesian colonizers, where it was used ceremonially and medicinally in various occasions (Nelson, 2007). Today the plant is still used, but mainly as a social beverage sold as a bottled drink in stores or served in bars or circles of friends. Awa products are manufactured and exported throughout much of the world and prescribed by some medical doctors for relief of anxiety (Nelson, 2007).

According to (Nelson, 2007), Awa is susceptible to a number of significant pests, especially where it grows in unshaded monocultures in Hawai. One of the severe fungal diseases of leaves and stems is known as “shot hole.” Shot hole first caused significant crop losses in the early 2000s as large ‘awa monocrops were planted in Hawai‘i. Aside from kava dieback caused by cucumber mosaic virus (CMV) and root disease caused by root-knot nematodes (Meloidogyne spp.), shot hole is the most economically important, widespread, and most difficult awa disease to manage effectively in Hawai‘i in higher rainfall areas of the state (Nelson, 2007).

The symptoms of shot hole disease on Piper methysticum leaves are;

On leaves, spots are small, initially black but later developing whitish to tan centers with well defined, dark margins. Centers of lesions tend to detach and fall away, creating holes in leaves. Leaves develop chlorotic (yellow) areas before defoliating prematurely. Adjacent lesions may coalesce. Spot symptoms are always visible on both sides of infected leaves. There may be dozens of distinct spots on a single leaf.

The symptoms of shot hole disease on Awa stem are;

On stems, spots are initially small and dark to black colored; they expand and develop whitish to tan colored centers that can develop cracks. The spots can extend into the stem below the epidermis, causing stem death and complete defoliation where enough spots accumulate.

2.1.2 Uses of Piper methysticum

i. Reduces anxiety in perimenopausal women

Along with climacteric symptoms, (Cagnacci et al, 2003) mood disturbances, particularly anxiety and depression, are frequent around the menopause. Although, they are dependent on modifications of central neurotransmitters consequent to rapid modifications of circulating gonadal steroids, their manifestation is influenced by individual factors such as education, socio-economic status and the woman capability to cope with daytime stress. Likely, they spontaneously vanish with time, but in the years of their manifestation, (Cagnacci et al, 2003) mood disturbances may greatly impact on the woman quality of life.

According to (Tarabusi et al,1999), Hormone replacement therapy may ameliorate mood but this pharmacological approach is sometimes contraindicated and frequently non-accepted by the woman. Benzodiazepines, and antidepressants, represent commonly used pharmacological remedies for mood disturbances, but their use is sometimes associated with side effects; the case of benzodiazepines are characterized by drowsiness, prolonged time of reaction, and dependence, and in the case of some antidepressants are characterized by anti-cholinergic and cardiotoxic effects. Alternative remedies are frequently used. Kava_ Kava, an extract from rhizome of Piper methysticum (Ernst, 2002), has been proposed as a ‘natural’ remedy for the treatment of anxiety. Indeed, Kava-Kava depending on the dose and type of preparation seems to induce variegate effects, among which are skeletal muscle relaxation, sleepiness and central effects ranging from depression to euphoria (Ernst, 2002). Kava plant contains 15 lactones also called kavalactones, which are chemicals that can affect the central nervous system. Several other types of tranquilizers and relaxant drugs also act upon this area in the brain. Like many other tranquilizers, the relaxant and mild euphoric effects of Kava occur rapidly after ingestion (Pittler and Edzard, 2000). Kava is commonly used to prepare a traditional beverage and pharmaceutical purposes (Pittler and Edzard, 2000).

ii. as a potential herbicide and fungicide

According to (Kohli et al, 1998), the inappropriate use of agrochemicals may give rise to undesirable side effects. He quoted, there may be a need to develop new management systems to reduce dependence on synthetic herbicide and insecticide based on ecological manipulations (Kohli et al, 1998).

The exploitation of allelopathic plants for weed control has gained in importance (Xuan et al, 2003). There are a number of higher plants, which show suppressive effects on other plants in their vicinity, but only some among them have shown effects on weeds and pathogen. Kava is a perennial pepper plant. Kava may exert its effects through similar mechanism as many more standard drug therapies.

2.1.3 Effect of Awa on the fungal growth

Findings in this study according to (Chikara, 2003) confirmed that Kava root had strong allelopathic activity, with significant inhibition on barnyardgrass, monochoria and knotgrass as well as five harmful fungi. According to (Chikara, 2003), Kava might be a promising material to biologically control the fast expansion of these paddy weeds.

2.1.4 Hepatotoxicity of Piper methysticum

Medical indications for kava include induction of relaxation and/or sleep, counteraction of fatigue, chronic cystitis, asthma, rheumatism, weight reduction, headache, and treatment of infections such as syphilis and gonorrhea (Singh, 1998). Traditionally, kava extracts are prepared from kava roots macerated with water or coconut milk (Johnson, 1999; Lebot et al, 1997). Some years ago, kava products became popular also in Western countries, mainly as an herbal alternative to drugs used in patients with anxiety disorders (Schulze et al, 2003). Commonly used drugs for this indication, E.g. benzodiazepines, selective serotonin-reuptake inhibitors or buspirone, are associated with adverse drug reactions such as withdrawal syndromes, memory changes, sexual dysfunction and others (Fricchione, 2004), which have not been described for kava products.

Apart from the so called kava dermatopathy, kava was not associated with severe adverse reactions (Bilia et al, 2002; Norton and Ruze, 1994). Kava dermatopathy includes yellowing of the skin, and the development of red eyes and a variety of allergic skin reactions, which are spontaneously reversible on stopping of the drug (Singh, 1992).

During the last few years, several patients with hepatic injury associated with the ingestion of kava have been described (Escher et al, 2001; Humberston et al, 2003; Russmann et al, 2001). In a case series, 82 cases of liver toxicity associated with the use of kava have been reported from several countries (Schmidt, 2003). According to (Schmidt, 2003), for 20 of these cases, however, there was no clear connection with the ingestion of kava. Twenty-one of these patients were treated concomitantly with potentially hepatotoxic drugs. In seven of these patients, the causality that kava was the cause for the hepatic injury could be doubted considerably for several reasons, whereas in 31 other cases, the available data were too fragmentary for a clear assessment. These left three cases, in which hepatic injury associated with the ingestion of kava, could be established as probable (Schmidt, 2003). Based on the clinical findings, it was hypothesized that liver injury associated with kava could have an immunological origin (Russmann et al, 2001; Schmidt, 2003; Schulze et al, 2003). Several other mechanisms and/or risk factors for hepatic toxicity of kava have been proposed, including the formation of electrophilic metabolites from kavalactones (Johnson et al, 2003), possibly associated with glutathione depletion (Whitton et al, 2003), and also genetic polymorphisms of CYP2D6 (Russmann et al, 2001).

Kavalactones, also called kavapyrones, are the major lipophilic compounds in the kava root and are claimed to be responsible for the anxiolytic effect of kava (Schulz et al, 1998). Accordingly, kava containing a high amount of kavalactones is generally considered to be of high quality (Dragull et al, 2003). The amount of kavalactones varies with the different parts, the age and the cultivar of the plant (Smith, 1983). Other researchers have found that the total kavalactone content is typically highest in the lateral roots and decreases continuously towards the aerial parts of the plants (Duve, 1976). Since it is not clear whether kavalactones are responsible for the hepatic toxicity of kava, it was speculated that other components of kava extracts and/or the extraction method could be the reason. (Nerurkar et al, 2004) and (Dragull et al, 2003) have investigated the alkaloid pipermethystine, a component of kava extracts, and found a stronger toxicity on HepG2 cells than for kavalactones. (Cote et al, 2004), compared the effect of an acetonic, an ethanolic and methanolic root extract with a (traditional) aqueous extract on Cytochrome P450 isozymes (CYP). All extracts inhibited the CYPs investigated, but the aqueous extract was the least potent inhibitor. Whether inhibition of CYPs is somehow connected with the hepatic toxicity of kava is currently not known.

The research by (Weise et al, 2002; Russmann et al, 2003), substantiating that the use of traditional aqueous extracts has risks similar to those by the treatment with ethanolic and acetonic kava extracts (Teschke et al., 2008). This raises the question to what extent the quality of the kava raw material, may be a major contributing factor for the toxicity rather than the used chemical extraction medium. The quality of kava depends on several major conditions and on their complex combinations (Lebot and Levesque, 1996; Lechtenberg et al, 2008). They include the chemotype and thus further studies summaries the characteristics of 14 patients with Hepatotoxicity in established causal relationship to the use of aqueous, ethanolic and acetonic kava extracts and kava–herbs mixtures.

2.1.5 Phytochemicals of Piper methysticum

The root of the kava shrub (Piper methysticum G. Forster, Piperaceae) is the source of perhaps the most important traditional beverage for many South Pacific Island peoples. This relaxing drink is prepared for ceremonial and recreational purposes (Lebot et al, 1997). During the past decade, kava has become a popular remedy in Europe (Dentali, 1997) and North America (Blumenthal, 1999) due to its anxiolytic properties (Bilia et al, 2002). Tablets, capsules and tinctures prepared from the lipophilic extracts have been widely available as non-prescriptive botanical dietary supplements (Davis and Brown, 1999). Since 1998, however, several European countries reported cases of liver damage allegedly due to medicinal usage of kava (Stoller, 2000). The products were subsequently banned in Germany (BfArM, 2002) and several other countries around the world.

Extensive work has been done on the chemistry and physiological effects of kavalactones, also known as styryl a-pyrones, the major lipophilic natural products in roots. They have been found to be responsible for the anxiolytic effect (Schulz et al, 1998), and kava with high kavalactone content is generally considered to be of high quality. One cepharadione (Jaggy and Achenbach, 1992) and two pyrrolidine alkaloids (Achenbach and Karl, 1970) have also been isolated and identified from kava roots as minor components. Their physiological activity is unclear. Since the major plant parts in traditional use of kava have been the rootstock and roots, far less research has been done on the chemistry of the aerial parts. In recent years, however, stem peelings are included as a raw material in kava commerce (Bennett, 2002) due to the high demand by the pharmaceutical industry. Also, leaves and branches have been used in folk medicine (Cambie and Ash, 1994; WHO, 1998) primarily for topical applications and kava leaf tea has appeared in health food stores. Smith (1979, 1983) discovered the alkaloid pipermethystine in leaves and stems of kava.


R = - N



Structure of Pipermethystine Structure of 3a, 4a- epoxy-5B-pipermethystine

Structure of Awaine Structure of Dihydropyridine

Kava is called awa in Hawaiian and also called awa in Nigeria, hence the name awaine. This new alkaloid was obtained as colorless oil with the molecular formula C14H17NO2. Awaine occurred primarily in the unopened leaves at a concentration range from 0.16 to 2.67 % (Kofron et al, 1992; Nogle et al, 2002). When leaves of different developmental stages from the same branch were compared, the concentration reduced sharply; only about half remained in the partially opened and minor amounts or none were found in the opened leaves.

The effects of these piperidine alkaloids on human physiology are unknown and their possible toxicity on the liver remains to be investigated. Several pyridone alkaloids with structures similar to 1 have been shown to be cytotoxic (Duh and Wu, 1990; Duh et al, 1990).

Furthermore, compound 1 decomposes on standing at room temperature due to hydrolysis of the amide, to give 3-phenylpropionicacid and the dihydropyridone 4 (Smith, 1979). Compounds 1 and 4 exhibit structural features of 2,5-dihydroxypyridine, which has been shown to affect DNA integrity in vitro due to its ability to redox cycle (Kim and Novak, 1990, 1991). Compound 2 is the first alkaloidal epoxide isolated from the kava plant. Its high concentration in the ‘Isa’ peelings suggests the ease of enzymatic epoxidation of compound1, resulting in a relatively stable product. Epoxidation of certain natural or xenobiotic compounds in liver has been well established as one of the mechanisms pertinent to hepatotoxicity (Zimmerman, 1999). The Pacific peoples prepare the time-proven kava drink using primarily the underground parts of certain preferred kava cultivars, and the use of alkaloid-rich stem peelings is avoided in general. In contrast, the raw material for extraction in the pharmaceutical industry may include stem peelings (Dentali, 1997; Secretariat of the Pacific Community, 2001).

Although we have no direct evidence on the presence of piperidine alkaloids in kava dietary supplements, the quantitative data, researches on this, suggest that products using kava peelings contain the piperidine alkaloids and their decomposition products. It is therefore compelled to advise caution on using the above-ground plant parts for human consumption.



3.1 Plant material

The plant used for this research, Piper methysticum locally known as Awa were collected from Oye market in Enugu State in July, 2010. The plant was identified by Mr. Ozioko, Alfred at BDCP, Nsukka. It is commonly grown in the eastern part of Nigeria where it is used mostly for the preparation of soup.

3.2 Extract Preparation

The sample of Piper methysticum leaves were washed thoroughly and dried under room temperature. The extraction of Piper methysticum leaves was done using 7.690g of the ground leaf sample in soxhlet extractor with distilled water in the department of biochemistry, Caritas University, Amorji Nike, Enugu State. The recycling of the solvent was allowed to be repeated for complete extraction. The slurry extracts were then poured into evaporating dish to evaporate the solvent in the extract over the water bath at the temperature of 80oC – 95oC and a yield of 17ml of crude extract was obtained.

3.3 Atomic Absorption Spectroscopy determination.

The water extract of Piper methysticum was later read in the atomic absorption spectroscopy to determine the actual concentration of mineral element present in the leaf extract.



As a result of the analysis carried out on the leaf, Piper methysticum, it was observed that Piper methysticum has a high mineral content which include the following:

Table 4.1 Absorbance and concentration of 7.690g of the extract


Absorbance (Ao)

Concentration (mg/ml)

Piper methysticum


0.125 x 10-3

Table 4.2 Concentration of manganese (Mn) in mg/180ml of extract






0.125 x 10-3

From Table 4.2 above, the dilution factor for the 180ml of extract used for the analysis of manganese gave the following result:

 Equation A
where 2.5 was the dilution factor used.

But 180ml of the extract was used, equation A will then be calculated thus:

 Equation B

But 7.690g of the sample was used in the extraction; the quantity in mg/g can be calculated thus:

Table 4.3 Concentration of Copper (Cu) in mg/180ml of extract


Mg Cu/mg





From Table 4.3 above, the dilution factor for the 180ml of extract used for the analysis of copper gave the following result:

Now to get copper contain in mg/g thus:

 Equation A
 Equation B

Since 7.690g of Awa leaf (dried) was used for extraction, quantity in mg/g:

Table 4.4 Concentration of Iron (Fe) in mg/180ml of extract




3.20 x 103

From Table 4.4 above, the dilution factor for the 180ml of extract used for the analysis of Iron gave the following result:

The copper content in 180ml (volume):

Since 7.690g of Awa was used for extraction. Therefore copper content in mg/g is thus:

Concentration of Zinc (Zn) in mg/180ml of extract

Since 7.690 of fresh Awa leaf was used for extraction, therefore:

Quantity in mg/g = 
Calcium – 0.13mg/g
Magnesium – 0.3mg/g
Sodium – 0.59mg/g
Potassium – 0.07mg/g

The subsequent values below were directly read using the Atomic Absorption Spectroscopy, while the previous (tabular) values are the confirmatory test of the specified mineral.

Tabular representation of the experimentally eight mineral constituent of Awa Leaf











Unit (mg/g)











5.1 Discussion

This research is aimed at studying the nutritive profile of a vegetable, Piper methysticum, locally known as Awa using Atomic Absorption Spectroscopy. Atomic Absorption Spectroscopy was used because it is the modern technique used to determine the concentration of a specific metal element in a sample. It can also be used to analyze the concentration of over 70 different metals in a solution.

This study was proposed because much research has not being done on this vegetable; therefore, it was my interest to venture into a research work on this plant used by the easterners mainly for preparation of soup which have also been researched to have some medicinal properties.

According to the result, Piper methysticum contains 0.13mg/g of calcium; calcium is the mineral that is mostly associated with bone health.

0.3mg/g of magnesium; magnesium is important in generation of ATP, muscle contraction and the transmission of nerve impulse.

Sodium and potassium with concentration 0.59mg/g and 0.07mg/g respectively are important in nerve conduction which helps generate the signals from the central nervous system to the muscles to perform work.

Manganese with concentration 0.0061mg/g, is an essential trace nutrient especially Mn-containing superoxide dismutase (Mn- SOD) which is enzyme used by nearly all organisms to deal with the toxic effects of superoxide. And 0.3mg/g of copper; copper is used for biological electron transport. It is also found in a variety of enzymes.

In the course of this work, it was discovered that Piper methysticum has a high iron content which is 3.1mg/g and also high zinc content 23.72mg/g mostly when compared to Dogogaro plant (Neem tree), while other mineral constituent of the vegetable were moderately okay.

Owing to the high concentration of iron in Piper methysticum, the consumption of the vegetable can be encouraged because iron is a trace mineral that is essential for our health. Forming a part of the pigment called hemoglobin in the blood, it gives blood the dark colour and helps transport oxygen to our cells. It is also important for muscle protein. A short term use of 80mg doesn’t cause harm, the safe upper limit is 15mg. therefore I suggest that frequent consumption of this vegetable, as regards to its iron content concentration 3.1mg/g will go a long way in preventing anemia, brain dysfunction, painful period, which are some of the common problem associated with lack of iron in the body.

The consumption of Piper methysticum is questionable considering the high concentration of zinc. Zinc is an essential mineral of exceptional biologic and public health importance. Its deficiency causes growth retardation in children, delayed sexual maturity, infection susceptibility, and diarrhea. Excess consumption of zinc can cause ataxia, lethargy and copper deficiency. Owing to the high concentration of zinc in Piper methysticum, I suggest that further studies should be done on this vegetable to know if the zinc content of Awa will be reduced by heating using the hot water extract procedure and lukewarm water procedure. This is important since in the cause of preparing the vegetable, is being passed through flame (heat). This should be done to certify if there is any effect of heat in reducing the concentration of zinc consumed.

5.2 Conclusion

In conclusion, Piper methysticum (Awa) is a highly nutritive vegetable that experimentally contains eight essential minerals of exceptional biologic and public health importance, including some phytochemicals which aids its function as a nutritive and also a medicinal plant. The mineral constituents of Awa are moderately okay except for iron and zinc which are high in concentration. Hence the high concentration of iron has encouraged the use of Awa, while further studies should be done to ascertain the effect of heat in the reducing the concentration of zinc for human consumption.


Bilia, A.R., Gallori, S. and Vincieri, F. (2002). Kava-kava and anxiety: growing knowledge about the efficacy and safety. Life Sciences 70: 2581–2597.

Blumenthal, M. (1999). Herb market levels after five years of boom: 1999 sales in mainstream market up only 11% in first half of 1999 after 55% increase in 1998. HerbalGram 47: 64–65.
Cagnacci, A., Volpe, A. and Arangino, S. (2003). Kava_/Kava administration reduces anxiety in perimenopausal women. Maturitas: The European Menopause Journal 44: 103 – 109
Chikara, J. (2003). Study on the allelopathy of Kava (Piper methysticum L.). MSc Thesis. Miyazaki University, Japan, p. 70.
Davis, R.I. and Brown, J.F. (1999). Kava (Piper methysticum) in the South Pacific: its importance, methods of cultivation, cultivars, diseases and pests. Canberra, Australia. p.13.
Dentali, S.J. (1997). Herb Safety Review. Piper methysticum Forster f. (Piperaceae). Herb Research Foundation, Boulder, CO.
Dragulla, K., Yoshidab, W. and Tanga, C. (2003). Piperidine alkaloids from Piper methysticum. Phytochemistry 63: 193–198
Duve, R.N. (1976). Highlight of the chemistry and pharmacology of yaqona, Piper methysticum. Fiji Agriculture Journal 38: 81–84.
El-Gamal, H.M., Shaker, H.K., Pollmann, K. and Seifert, K. (1995). Triterpenoid saponins from zygophyllum species. Phytochemistry 40 (4): 1233–1236.
Ernst, E. (2002). Safety concerns about kava. Lancet 359: 1865.
Fricchione, G. (2004). Clinical practice: Generalized anxietydisorder. N. Engl. J. Med. 351: 675– 682.
Gow, P.J., Connelly, N.J., Hill, R.L., Crowley, P. and Angus, P.W. (2003). Fatal fulminant hepatic failure induced by a natural therapy containing kava. Medical Journal of Australia 178: 442–443.
Hamdy, A., Mansour, A., Al-Sayeda, A., Newairya, M.I. and Sheweitac S.A. (2002). Biochemical study on the effects of some Egyptian herbs in alloxan-induced diabetic rats. Toxicology 170: 221–228.
Humberston, C.L., Akhtar, J. and Krenzelok, E.P. (2003). Acute hepatitis induced by kava kava. Journal of Toxicology/Clinical Toxicology 41: 109–113.
Ibrahim, N.M. (1990). MSc Thesis. Institute of Graduate Studies and Research, Alexandria University pp.1–150.
Ibrahim, R.F. (1998). MSc Thesis. Institute of Graduate Studies and Research, Alexandria University, pp. 1–124.
Jaggy, H. and Achenbach, H. (1992). Cepharadione A from Piper methysticum. Planta Med. 58: 111
Johnston, E. and Rogers, H. (2006). Hawaiian ‘awa. Views of an ethnobotanical treasure (808) 323- 3318.
Kaefer, M.C. and Milner, J.A. (2008). The role of herbs and spices in cancer prevention. Journal of Nutritional Biochemistry 19: 347–361
Kohli, R.K., Batish, D. and Singh, H.P. (1998). Allelopathy and its implications in agro-ecosystems. Journal of Crop Production 1: 169 – 202.
Lebot, V. and Levesque, J. (1996). Genetic control of kavalactone chemotypes in Piper methysticum cultivars. Phytochemistry 43: 397–403.
Lebot, V., Merlin, M. and Lindstrom, L. (1997). Kava, the Pacific elixir. Yale University Press, New Haven.
Mansour, H.A. and Newairy, A.A. (2000). Amelioration of impaired renal function associated with diabetes by Balanites aegyptiaca fruits in streptozotocin-induced diabetic rats. Journal of Medical Research Institute. 21 (4): 115–125.
Metuh, E.I. (1987). Comparative Studies in African Traditional Religion. A division of Eternal Communication, Nigeria. P. 74
Nelson, Scot. (2007). Plant Disease. Journal of Ethnopharmacology 123: 378 – 384
Nerurkar, P.V., Dragull, K. and Tang, C.S. (2004). In vitro toxicity of kava alkaloid, pipermethystine, in HepG2 cells compareds to kavalactones. Toxicological Science 79: 106–111
Pittler, M.H. and Edzard, E. (2000). Efficacy of kava extract for treating anxiety: systematic review and meta-analysis. Journal of Clinical Psychopharmacol 20: 84 – 89.
Reaven, G.M. (1983). Effect of age and diet on insulin secretion and insulin action in the rat. Journal of Medicine. 74: 69.
Russmann, S., Lauterburg, B.H. and Helbling, A. (2001). Kava hepatotoxicity. Ann. Intern. Med. 35: 68–69.
Schulze, J., Raasch, W. and Siegers, C.P. (2003). Toxicity of kava pyrones, drug safety and precautions—a case study. Phytomedicine. 10: 68–73
Singh, Y.N. (1998). Blumenthal M. Kava, an overview. Herbalgram. 39: 33 - 55.
Smith, R.M. (1983). Kava lactones in Piper methysticum from Fiji. Phytochemistry 22: 1055–1056.
Sodimu, A.I., Faleyimu, O.I., Olorukooba, M.M. and Sanusi, A.O. (2008). International Journal of Development in Medical Sciences. Vol.1.
Stoller, R. (2000). Leberscha¨ digungen unter Kava-Extrakten. Schweizerische A¨rztezeitung 81: 1335–1336.
Teschke, R., Gaus, W. and Loew, D. (2003). Kava extracts: safety and risks including rare hepatotoxicity. Phytomedicine 10: 440–446.
Teschke, R., Moreno, F. and Petrides, A.S. (1981). Hepatic microsomal ethanol oxidizing system (MEOS): respective roles of ethanol and carbohydrates for the enhanced activity after chronic alcohol consumption. Biochemical Pharmacology 30: 1745–1751.
Teschke, R., Neuefeind, M., Nishimura, M. and Strohmeyer, G. (1983). Hepatic gammaglutamyl- transferase activity in fatty liver: comparison with other liver enzymes in man and rats. Gut 24:625–630.
Teschke, R. and Petrides, A.S. (1982). Hepatic gamma-glutamyltransferase activity: its increase following chronic alcohol consumption and the role of carbohydrates. Biochemical Pharmacology 31: 3751–3756.
Teschke, R. and Schwarzenboeck, A. (2009). Suspected hepatotoxicity by Cimicifugae racemosae rhizoma (black cohosh, root): critical analysis and structured causality assessment. Phytomedicine 16: 72–84.
Teschke, R., Schwarzenboeck, A. and Hennermann, K.H. (2008). Kava hepatotoxicity: a clinical survey and critical analysis of 26 suspected cases. European Journal of Gastroenterology and Hepatolology 20: 1182–1193.
Weise, B., Wiese, M., Plotner, A. and Ruf, B.R. (2002). Toxic hepatitis after intake of kava-kava. Verdauungskrankheiten 4: 166–169.
Whitton, P.A., Lau, A., Salisbury, A., Whitehouse, J. and Evans, C.S. (2003). Kava lactones and the kava-kava controversy. Phytochemistry 64: 673–679
Xuan, T.D., Tsuzuki, E., Matsuo, M. and Khanh, T.D. (2003). Kava root (Piper methysticum L.) as a potential natural herbicide and fungicide. Crop Protection. 22: 873 - 881
Zimmerman, H.J. (1999). Hepatotoxicity: The Adverse Effects of Drugs and Other Chemicals on the Liver, second edition. Lippincott Williams & Wilkens, Philadelphia, PA, Pp. 11–40.

База данных защищена авторским правом © 2016
звярнуцца да адміністрацыі

    Галоўная старонка