In ntroduct Chapter- tion -1
Introduction
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Chapter-
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INTRODUCTION
Chapter-1 “They are without leaves, without buds and without
flowers yet they form fruit”
1.1 Mushroom: A fungus
This intellectual definition delinrates macrofungi through the vison of S. T. Chang
(1993), an eminent mycologist, tha captures the essence of its versatility and
beauty. Technically speaking “macrofungi” that are mostly scattered throughout
Ascomycota, Basidiomycota and Zygomycota are defined as those fungi which
bear large, easily observed spore-bearing structures that are formed above or
below ground (Mueller et al., 2007). A recent global study regarding macrofungal
diversity estimated it to be within the range of 53,000 to 110,000 species (Mueller
et al., 2007).
Under the term ‘‘useful mushroom’’ (Lelley, 2005) all the mushrooms which
are used by man for some economical importance are considered. This would
contain all the edible mushrooms, toxic or cryptic mushrooms with medicinal
properties, mushrooms that can be used in forestry, industry, biotechnology,
bioremediation, restoration, reforestation, etc. Wild mushrooms are believed to be
one of the most important non-wood forest products. Almost 3000 species or
more have gastronomical uses and 100 or more have promising clinical activity
against cancer and other chronic diseases. Because of which UN-FAO promotes
sustainable use of macrofungi and use them for forests management and
conserve their biodiversity as well that would have a long term effect on income-
generation and food security (FAO, 1991).
1.1.1 An overview on fungi
Fungi is one of the most prominent and biodiverse organism to inhabit and
influence this planet. They are neither animal nor plant though some people
consider them plants for various reasons, but they differ from plants in that they
lack the green chlorophyll that plants use to manufacture their own food and
energy. For this reason they are placed in a different Kingdom of their own. The
true fungi belong to the kingdom Eukaryota that encompasses 4 phyla, 103
orders, 484 families and 4979 genera (Manoharachary et al., 2005).
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INTRODUCTION
Chapter-1 Fungi play critical role in ecosystem be it grassland and forest ecosystems
they are equally vital as they are an indispensible link in the food web as
decomposers and pathogens that have many different kinds of associations with
other organisms, both living and dead. In other words being heterotrophs it is
involved in decomposition, nutrient cycling, and nutrient transport and are
indispensable for achieving sustainable development (Palm and Chapela, 1998).
They serve the plant kingdom by mutualistic ties to which over 90% of plants
subscribe in form of mycorrhizal associations enabling them to scavenge essential
minerals from nutrient poor soils. They are also known for their positive and
negative economic impacts on human beings. On the positive axis they are
employed for brewing, baking, industrial fermentation, pharmaceutical and
biotechnical exploitation and direct cultivation as food. Industrial use of fungi has
now developed in leaps and bounds. Apart from edible mushroom cultivation of
several species other direct or indirect commercial engagements are being
pursued. Fungi have become integral to immunosupressive drugs, steroids,
hormones, organic acids, and fermented foods as soy, cheese, fabric finishing,
pollution treatment and several other such processes. On negative axis they
cause diseases in humans, animals and plants and degrade artifacts and utility
materials. Mycotoxins from micro- and macrofungi cause harm and even fatality to
animal and human lives each year. They have the most awesome methods and
strategies of dissemination as Entomopbtbora muscae, that infects houseflies and
reaches its brain to cause it to crawl high where it can sproulate and spread
further (Carlilie et al., 2001).
1.1.2 Biodiversity of fungi
Fungi is the 2nd most diverse of all groups and is considered as a prime
member of the other “mega-diverse” groups like insects, bacteria, arachnids and
nematodes (Gaston, 2000; Hawksworth and Kalin-Arroyo, 1995). Hawksworth
estimated the total number of fungal species by calculating that there is an
average of six known fungal species for every known plant species in Finland,
Switzerland, the UK and the USA. Based on an estimated 250,000 plant species
worldwide, Hawksworth calculated that there are approximately 1.5 million extant
fungal species, of which 95% are not described (Hawksworth and Rossman,
1997). However, the high species richness predicted by the ‘‘ratio estimate’’ has
been cast into doubt. But some studies based on meta-analysis of macrofungal
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INTRODUCTION
Chapter-1 diversity have shown that tree diversity is a promising surrogate for macrofungal
diversity at large spatial scales (Schmit et al., 2005). An interesting study
highlighted that the rate at which 74,000–120,000 species of total 1.5 million
fungal species were discovered it would theoretically take 1290 years without
considering the rate of extinction (Hawksworth, 2001).
The comparison of diversity of fungal species on global and Indian levels is
compared below (Table 1.1). The Ascomycotina and Deuteromycotina are the
least estimated at national level, which doesn’t necessarily indicate that they are
rare but the current scenario may be due to the paucity of data. According to
Manoharachary et al. (2005), 205 new genera have been described from India. Of
these, approximately 27,000 species are reported to colonize diversified habitats
implying that there has been a 10 fold increase in registering the species during
past 70 years.
Table 1.1. An estimate of Fungal diversity in India (Manoharachary et al., 2005)
PHYLA GLOBAL INDIA Percentage
Myxomycotina 450 380 84.44
Mastigomycotina 308 205 66.55
Zygomycotina 55 50 90.91
Ascomycotina 2000 745 37.25
Basidiomycotina 357 232 64.98
Deuteromycotina 4100 468 11.41
Total 7270 2080 28.61
1.1.3 The taxonomic shelters of macrofungi
The kingdom fungi include a wide variety of whopping diversity in terms of
micro- or macroscopic morphology, ecological niches occupied, metabolism and
reproduction. An estimate revealed that 80% of the species in species-rich groups
of fungi are distributed widely and only 20% are distributed in limited niches. More
than 90% of fungi are yet to be evaluated for antibiotics in light of the current
challenge of microbial resistance. The Eumycota or true fungi are broadly divide
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INTRODUCTION
Chapter-1 under the classes Chytridiomycetes, Zygomyces, Ascomycetes, Basidiomycetes,
and Mitosporic fungi.
Ascomycetes and Basidiomycetes, which contain most of the macrofungal
species, in addition to producing spores by a sexual process, form other types of
spores asexually and are known as ‘Higher fungi’. Different kinds of large fungi or
macrofungi have been recognized for thousands of years. In current English
edible ones are often called mushrooms and poisonous ones toadstools, which
are not taxomonical terms. During the eighteenth century, botanists made
considerable progress in the recognition and classification of the fungi, and early
microscopists observed and described hyphae and spores. The role of the edible
fruit bodies (or fruiting bodies) is the production of large numbers of spores by
means of which dispersal occurs. The spores are borne on the gills below the cap,
and a stalk raises the fruit body above the ground to facilitate spore dispersal by
air currents. Examination of the stalk, cap and gills with a microscope shows that
the fruit body is composed of long, cylindrical branching threads known as
hyphae. The hyphae are divided by cross-walls into compartments, which typically
contain several nuclei. Such compartments, together with their walls, are
equivalent to the cells of other organisms. The spores are borne on specialized
cells termed basidia in the Basidiomycetes or in sac like structures called ascus in
Ascomycetes (Carlilie et al., 2001).
The Ascomycota is the largest phylum of the Kingdom Fungi, with
approximately 32,000 species (Hawksworth et al., 1995). Three major groups or
classes of Ascomycota, including Euascomycetes (mostly filamentous,
sporocarpproducing as well as mitosporic or conidial forms), Saccharomycetes
(the true yeasts), and Archiascomycetes (a paraphyletic assemblage of basal
taxa) generally are recognized (Nishida and Sugiyama 1994; Taylor et al., 1994).
The Euascomycetes is the largest class of Ascomycota and includes the major
lineages of filamentous, sporocarpproducing taxa and their equally diverse
asexual relatives (anamorphs). It is arguably the most successful group of fungi,
including parasites, pathogens, and mutualists of plants, algae, and animals, as
well as saprobes able to decompose virtually all known organic substrata.
Pezizales is a basal lineage of the class (Berbee and Taylor 1993; Gargas et al.
1995; Platt 2000). It also may be the best-known and largest group of apothecial
fungi and includes numerous macroscopic forest species (e.g., Morchella species,
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INTRODUCTION
Chapter-1 Gyromitra species, Helvella species). The Pezizales is characterized by
operculate asci. The monophyly of the order is not strongly supported, however,
and numerous familial revisions have been proposed (O’Donnell et al., 1996).
Moreover, the group includes numerous, independent lineages of truffles
(O’Donnell et al. 1996) and, as an order, probably contains the majority of
ectomycorrhizal species of ascomycetes. Pyrenomycetes is a class name
formerly used to refer to a group of species with a particular shared morphology. It
now is used to designate a clade that includes the orders Diaporthales,
Halosphaeriales, Hypocreales, Lulworthiales, Microascales, Ophiostomatales,
Phyllachorales, Sordariales, and Xylariales (Hausner et al. 1992; Spatafora and
Blackwell 1993; Kohlmeyer et al. 2000). Although the taxa in the clade
encompass a wide range of macromorphologies and micromorphologies, the vast
majority have a flask-shaped ascomata or perithecia.
The Basidiomycota is the second largest phylum of Kingdom Fungi, with
approximately 23,000 species (Hawksworth et al. 1995), including many of the
common macroscopic forest fungi (e.g., mushrooms, shelf fungi). Classifications
of the Basidiomycota, with fungi possessing septate basidia assigned to the
Phragmobasidiomycetes (Heterobasidiomycetes) and fungi with nonseptate
basidia classified in the Homobasidiomycetes (Holobasidiomycetes) (Donk, 1966).
Basidiomycota generally is considered to include the classes Urediniomycetes
(rusts and relatives), Ustilagniomycetes (smuts), and Hymenomycetes
(mushrooms and relatives) (Wells, 1994). The Hymenomycetes consists of the
fleshy forest fungi (e.g., mushrooms, jelly fungi, shelf fungi) with which biologists,
naturalists, and nonmycologists are most familiar. The clade is united by a unique
mycelial structure, the dolipore septum, in which the cell walls near the pore of the
septum flare, and a membrane structure, the parenthesome, occurs on either side
of the pore (Moore, 1985). The parenthesome may be perforated or not,
depending on the clade, with the imperforated form being ancestral for the class.
homobasidiomycetous taxa with nonseptate basidia that lack a yeast phase in
their life cycles. This clade includes the mushrooms, shelf fungi, and stinkhorns,
all of which may produce mycorrhizae, decay litter and wood, or act as plant
pathogens and insect symbionts. Traditional classifications of the
homobasidiomycetous fungi were based largely on basidiocarp morphology with
particular emphasis on the sporeproducing region or hymenophore. For example,
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INTRODUCTION
Chapter-1 all of the mushrooms and their gilled relatives were grouped in the Agaricales, and
all of the poroid forms and their relatives were grouped in the Aphyllophorales.
The consensus arising from those studies is that overall, basidiocarp morphology
it is not a phylogenetically informative trait at higher taxonomic levels because of
repeated episodes of convergent and divergent evolution. The Hymenomycetes
includes an estimated eight major clades each of which encompasses multiple
basidiocarp and hymenophore morphologies like Polyporoid, Euagaric, Bolete,
Thelephoroid, Russuloid, Hymenochaetoid, Cantharelloid and Gomphoid-phalloid
(Hibbett and Thorn 2001). Morphologically the mushrooms can be broadly divided
in the following forms, as bracket shaped, stiped and poroid, gilled, smooth and
resupniate on woods, coralloid, hood like, dentoid or with cup shaped cap having
or lacking stipe etc. (Pacioni and Lincoff, 1981) some of the examples are given
below (Fig 1.1).
Figure 1.1. Various morphological forms of macrofungi.
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INTRODUCTION
Chapter-1 1.2 Bioprospecting
1.2.1 Bioprospecting: Defining it
Bioprospecting is defined as “the purposeful evaluation of wild biological material
in search of valuable new products” (Artuso, 2002). Biodiversity prospecting is the
exploration of wild plants and animals for commercially valuable genetic and
biochemical resources.
Ants of the tribe Attini and other termites known to rear and consume
mushrooms for over 50 million years are the natural frontiers of bioprospecting
(Muller, 1998). Ever since mankind has started living in community be it small or
large, the bioprospecting of nature for battling diseases has been a never ending
story. The trial and error efforts directed towards the betterment of the quality of
life was compiled orally or textually in due course of time, so that it can be
communicated vertically down the generations. Today contemporary natural
medicines in use have that are pure and well-defined chemotherapeutic chemical
entities. The evolution from herbal remedies to novel chemical entities in clinical
use today was a slow and gradual process that started with inquiring minds at the
beginning of the 19th century (Wetzel et al., 2010).
Friedrich Wilhelm Adam Serturner, a German pharmacist, reported the
isolation of a white crystalline powder from opium (Papaver somniferum), which
he named morphine in earlier 18th century. This was the 1st isolation of a pure
natural product that was commercialized two decades later by Heinrich Emanuel
Merck. The same molecule and several classes of analogues are being used as
analgesics even after 200 years. Later this led to isolation of several natural
products as strychnine, colchicine and codeine (Sneader, 2005).
The fact that 214,000 chemical entities are known to us indicates that
mankind has traversed a long way in drug discovery and bioprospecting in a
major way (DNP, 2010). The 20th century witnessed the discovery of the
antibacterial properties of penicillin, derived from the mould Penicillium notatum,
which was soon followed by various other antibacterials that gave physicians an
enormously powerful weapon in their battle against infectious diseases (Ji et al.,
2009).
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INTRODUCTION
Chapter-1 The products intended as outcome of bioprospecting programs range from
pharmaceuticals, agrochemicals, cosmetics, flavorings, fragrances to even
industrial enzymes. Post Convention of Biodiversity Intervention the
bioprospectors have become accountable to the countries from which biological
material had been collected. Thereafter the equitable benefit sharing and
technology transfer is required in exchange for access to biochemical resources
that include include genetic material as well as other chemical compounds that
can be derived from biodiversity.
Analysis of effective economic models estimating the value of biological
samples for pharmaceutical research revealed that demand curve for biological
samples is downward sloping because the market price for randomly collected
biological samples is likely to be little more than the cost of collecting them
(Simpson et al., 1996). The optimal bioprospecting strategy is expected to trigger
knowledge generating investments. Bioprospecting activities are intended to
support sustainable development in terms of widespread, long-term improvement
in economic opportunity and environmental well being, that bags incentives for
conservation. Moreover, apart from drug discovery resource sharing, the
validation of effective traditional practices can give rise to opportunities for
developing commercial-scale operations for production and extraction of
biochemical materials like raw materials, extracts, fractions, drug powders,
infusions or any of these in convenient pharmaceutical forms. The bulk supply of
raw materials and purified natural products can provide a source of revenue and a
means of developing technical and management capabilities. But, the laws of
supply and demand still hold; unless the commodity can be differentiated on the
basis of quality or other characteristics, prices and profits will be limited by the
ability of other suppliers to enter the market. These can offer for immediate
sustainable development and opportunities can grow with expanding market.
Apart from India several countries like Argentina, Australia, Bermuda,
Cameroon, Chile, China, Costa Rica, India, Indonesia, Jamaica, Malaysia,
Mexico, Nigeria, South Africa, and Suriname have actively taken part in
bioprospecting programs. Costa Rica and South Africa are two countries that are
using the experience and technical capabilities gained from initial bioprospecting
endeavors to develop more comprehensive value-added bioprospecting
programs. Since 1990 South Africa’s is actively progressing to develop the
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INTRODUCTION
Chapter-1 chemical and genetic value of its biodiversity. After completion of pilot projects
with several industrial participants the Chemtek division of South Africa’s
Commission on Scientific and Industrial Research launched its own pilot
bioprospecting effort. As a result of this effort an antiobesity agent named P57
was discovered from an indigenous South African plant. They were able to obtain
its intellectual property rights even though P57 is a mixture of phytochemicals.
This in turn led to the formation of a bioprospecting consortium involving
Commission on Scientific and Industrial Research, the South African Medical
Research Council, the Agricultural Research Council, the National Botanical
Institute, and several universities that road-mapped to evaluate the
pharmaceutical potential of all 23,000 species of vascular plants native to South
Africa. Meanwhile pushing forward the P57 project they have collaborated with
UK-based Phytopharm for technical assistance regarding manufacturing FDA
guidelines and Pfizer for funding to develop a manufacturing facility to produce
sufficient quantities of P57 for clinical trials. On the successful completion of the
project the parent body will receive a part of revenue (Horak, 1998).
Bioprospecting for genetic material that codes for medicinally or
agronomically valuable traits is targeted for the production of transgenic crop
varieties. The newly developed ‘‘golden’’ rice variety that many hope will help
reduce vitamin A deficiency in developing countries was developed using genes
from daffodils and two species of bacteria. The Diversa Corporation, a rapidly
growing biotechnology company that has entered into bioprospecting agreements
not only in Costa Rica and South Africa but also in Indonesia, Iceland, and
Bermuda, uses microbial DNA extracted from soil samples to genetically engineer
common microorganisms to produce novel chemical compounds. Biotechnological
techniques are also used as a means of producing commercial quantities of
complex natural products that were discovered through bioprospecting activities,
but have proven too difficult or costly to synthesize chemically. Examples include
the anti-cancer drug taxol, which was originally derived from the bark of the
Pacific Yew tree but is now produced using tissue culture techniques, and the
anti-coagulant hirudan, which is a chemical isolated from the saliva of the
common leech, Hirudo medicinalis, but is now produced in commercial quantities
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INTRODUCTION
Chapter-1 from transgenic strains of bacteria as well as from transgenic plants (Walsh,
2000).
Similarly the collaboration between Merck and Costa Rica’s National
Institute of Biodiversity has been fruitful in isolating novel compounds such as
arundifungin (Cabello et al., 2001) and durhamycin A (Jayasuriya et al., 2002).
1.2.2 Bioprospecting of traditional databases
The ethnobotanical-driven discovery of novel pharmacological agents highlights
the potential for using collected indigenous knowledge as a research tool.
Prostratin, an HIV therapeutic that activates the latently infected T-cell pool (Korin
et al., 2002), is a recent example of a potentially beneficial and lucrative
compound identified through ethnobotanical work in Samoa. Common to all drug
discovery programs high-throughput screening employed to identify potential
therapeutic leads by the application of a ‘brute-force’ method to examine
specimens for activity are lately found to be inefficient. This is because the
compounds that were active in vitro were inactive in vivo, as witnessed by a large,
random library screen for antiretrovirals that failed to identify any compounds that
possessed in vivo activity (Chapman et al., 2002). On the other hand there are
several mentions of medico-ethnobotanical records made by historians,
physicians, expatriates and indigenous people. Most of the herbal texts have been
preserved as historical artifacts, but lately, its potential in unraveling prized
ethnomedicinal practices have been realized. Gerard’s The Herball (Cox, 1998)
and plants in Herbarium Amboinense (Rumphius, 1741-1755) have firm-footed
these endeavors as several potent pharmaceutical constituents have been
unleashed on this line. Texts detailing natural pharmaceuticals have been found
that date back to the ancient Egyptians and Sumerians (c. 3100 BC). Records in
hieroglyphs (Egypt) and cuneiforms (ancient Mesopotamia) are frequently recipes,
usually listing the ailment and providing ingredients and preparation and
administration instructions (Estes, 1989; Manniche 1989). Hundreds of unstudied
Latin, Greek and Arabic herbal texts and recipe books from the Middle Ages
remain in manuscript depositories across Europe, northern Africa and the Middle
East.
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INTRODUCTION
Chapter-1 In several remote places that lack medical facilities, the community
traditional practices are prevalent. They use biological cures for disease that
aren’t laboratory produced or patented. Envisioning the immense potential
harnessed by these traditional practices a surge of interest in drug discovery
based on ethnomedicinal foundation has long taken off. Though this search is
often called bioprospecting, but it may also be termed biopiracy by those who
disapprove of the occasionally exploitive methods used by large companies
desirous of being the first ones to patent a newly discovered biological “cure”. The
current work is registered with State Department of Forest, biodiversity division
and is being officially permitted.
A growing demand for herbal medicines in North America and Europe as
well as rise in epidemics like malaria, tuberculosis and HIV/AIDS in Sub-Sahara
African have created an expanding market for indigenous herbal medicines
(Reihling, 2008). Traditional healers, plant gatherers, petty traders, research
institutions and private corporations have assembled around the issues of
standardization and commercialization of local knowledge about plants.
Bioprospecting is engaged by highthroughput screening or through traditional
healers. Both of these strategies have been combined to maximize the outputs
(Berlin and Berlin, 2005).
1.2.3 Resources of and traditional practices in ethnomycology
Ethnomedicinal use of plants is probably 60,000 years or more old, when their use
by Neanderthals is evidenced by the pollen deposits at one of the graves of
Shanidar caves located in the Zagros Mountains of Kurdistan in Iraq (Solecki,
1975). Some texts from Mesopotamia, circa 2600 BC are believed to be the oldest
medical oeuvre compiled on hundreds of clay tablets in cuneiform and
encompasses medicinal details on 1,000 plants and plant-derived substances,
such as the oils of Cedrus species (cedar), the resin of Commiphora myrrha
(myrrh) and the juice of the poppy seed Papaver somniferum (Newman et al,
2000). Around 800 complex prescriptions and more than 700 natural agents such
as Aloe vera (aloe), Boswellia carteri (frankincense) and the oil of Ricinus
communis (castor) are found in the ancient Egyptian Ebers Papyrus that date
back to 1550 BC (Zhong and Wan, 1999). Descriptions on more than 400 natural
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INTRODUCTION
Chapter-1 agents in delineated the work called Corpus Hippocraticum by the Greek
physician Hippocrates of Cos around circa 460–377 BC (Castiglioni, 1985).
Medicinal use of some of these herbs is still found to be prevalent among several
communities.
The advent of Ethnomycology was witnessed long before the very term
being coined by R. Gordon Wasson (1967), who also unleashed the depiction of
“Soma” as a mushroom summed up in 120 slokas. An excerpt from, “Rigveda”,
explicitly matches the morphology of a mushroom. It is a collection of ancient
Indian sacred hymns dated back to the late Bronze Age, which would be
between 1700–1100 BC. Soma is an ancient drug that was used for long life and
consumed as worship by the priests of Rig Veda. It was appreciated for its life
extending other therapeutic and psychological effects. It is believed to be
introduced by the Aryan people, when they inhabited valleys of Northern India.
Soma was said to be the symbol of power of sacrifice and was a common
sacrificial offering. It was a drink made before the sacrifice and was consumed by
the priests. The 9th book of Rigveda is loaded with attributes and importance of
soma (Mulhollan, 1980). There has been a lot of debate on whether soma is
mushroom or not. Though the arguments are focused majorly on Amanita not
being the ideal soma and this has been the source of disagreement. This was
proposed by Wasson in connection to other Eurasian practice linked to its
psychoactive species. There are compelling evidences like verses sighterd below
which match to the morphology of an agaric mushroom. Thus it may be possible
that the soma can be another mushroom rather than any species of Amanita as it
is said to be confined to mountains.
V 43 4c madhvo rasam sugabhastir giristham
Meaning - Plant from mountain
V 85 2d divi suryam adadhat somam adrau
Meaning - he has placed soma on mountain top
IX 62 4A asavya amsur madayapsu dakso gristhayah
Meaning - soma stalk seated on mountain top
IX 66 5 pari dhamani yani te tvam somasi visvatah pavamana rtubhih kave
Meaning – Your shining rays spread a filter on the back of heaven, O Soma, with thy forms.
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INTRODUCTION
Chapter-1 This may also relate to macrofungi which may have luster like Ganoderma
lucidum. The juice was taken directly or with milk or curd. IX 69 5 pra kristiheva susa eti roruvad asuryam varnam ni rinite asya tam jahati vavrim pitur eti niskrtam upaprutam krnute nirnijam tana Meaning – Aggressive as a killer of people he advances, bellowing with power.
He sloughs off the saurian color that is his. He abandons his envelope, goes to the rendezvous with the father. With what floats he makes continually his vesture-of-grand-occasion.
This disposition is attributed to the universal veil found in agarics and is closest to
the description of the mushroom.
Since its identifying characters were not mentioned the Soma of Rigveda
was changed to another form that was clearly defined in later religio-medical texts.
This religion based science is thought to develop since 6000 BC (Lee, 1949). The
principles of Ayurveda that stemmed from Atharvaveda were organized into
treatises around 800 BC, by Charaka and Sushruta (Sneader, 2005). Bower
manuscript, which is the excavated oldest preserved written material dated to the
4th century AD, has mentions of the works of Sushruta (Kutumbian, 1999)
indicating that it was a very prevalent school of practice. The teachings of sage
Sushruta was earlier put together in form of a treatise known as “Sushruta
Samhita”. It has 184 chapters that encompass issues regarding 1,120 illnesses,
700 medicinal plants, 64 and 57 preparations from mineral and animal sources
respectively (Dwivedi and Dwivedi, 2007). In this awesome compilation Sushrut
classifies mushrooms according to its theraputic effect, ecology and gastronomic
outcomes. They were in general addressed as “Udbhida” and were presented as
follows.
� Palala: These grew on stacks of straw were claimed to be sweet in taste
and digestion, produced a state of dryness and subdued the 3 deranged
humours of the body.
� Venn: These grew on the stems of bamboo and were found to be
astringent in taste and aggravated the bodily Vayu.
� Ikshu: These grew on the sugar-cane were claimed to be sweet pungent in
taste leaving behind an astringent after taste were cooling in potency.
� Udbhida: These were hypogeal or said to appear from beneath the surface
of the ground. They were heavy to digest and didn’t generate the Vayu.
Their tastes varied according to the nature of the soil.
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INTRODUCTION
Chapter-1 � Karisha: These grew on the compost heap of decomposing cow-dung and
were claimed to aggravate Vayu or were know to be heat generating in
other words.
At the end of his discussion Sushrut stated that the shepherds knew better
about these in greater deal and can be counsulted for more onformation. Thus in
other words he suggested that the enthnomycological database amongst the
forest wanderers were rich as they took the cattle for grazing and did
bioprospecting of macrofungi for edible or medicinal use. This was taken into
account and thus apart from traditional practitioners, such people were also
involved in the study.
Documented medicinal use of mushrooms laps back to18th century in case
of wound healing by Fomes fomentarius in (Roussel, 2002), also recorded along
with Piptoporus betulinus from an 5300 years old “iceman” (Stamets, 2002).
Traditional medico-chronicles of Slavic countries enshrine around 40
medicinal species for numerous human diseases. Rural Russian people of
Kamchatka believed Amanita muscaria (fly agaric) as "the god of hard drinking
and a chief of poisonous potions," and those in Kostroma region used its tinctures
against stomachache or gastric disease and other diseases. The farmers used it
as soporific by taking five or six drops to fall asleep. In Belorussia its mycelia were
grown on cow dung from pileus and were used against rheumatic aches by
rubbing it on the sore area. In Siberia its tincture was taken as a beverage to aid
in the healing of broken bones after fractures. One of the first medicinal
mushrooms taken at the Fomitopsis officinalis (larch polypore) was taken as the
direct orders of the Russian Tzar and was later used as styptic and purgative or to
treat bronchial asthma, night sweats of tubercular patients. American-Indian
believed that F. officinalis had miraculous powers. In Ancient Rome Pliny the
Elder suggested its use for treatment of stomach, dyspepsia, liver (including
jaundice), kidney, and urinary bladder (especially when urination is difficult, such
as while passing bladder stones) diseases; against tuberculosis, asthma,
epilepsy, and also as antidote after snake, spider, or scorpion bites. Siberian
farmers used it as a styptic to cauterize a bleeding wound, and against
indigestion, hemorrhoids, uterus, breast, esophagus, and stomach cancers.
Similarly Fomitopsis pinicola (red-belted polypore) was very common in the
Eastern countries for its antitumor and sedative properties. Moreover, the
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INTRODUCTION
Chapter-1 American Pharmacopoeia of the 19th century recommended F. pinicola for stable
spasmodic fevers, chronic diarrhea, dysentery, jaundice, and diuresis. This
species was known in eastern Canada as "Mech quah" and was used as an
emetic for stomach cleansing (Denisova, 1998).
Inonotus obliquus (Clinker Polypore), known as chaga, was used for
treatment of different gastrointestinal diseases (ulcers, gastritis) and sometimes
against lip, skin, stomach, and rectal cancers throughout Russia including Ural,
Siberia, Poland and Baltic countries. Since centuries malignant tumors are treated
with chaga or Phellinus nigricans. E. Froben, a physician, from Russia reported
recession of parotid gland cancer upon treatment with Piptoporus betulinus
decoction. Moreover, Russians also used puffballs
(Lycoperdon and Calvatiaspecies) with hot wine to treat constipation. Mushrooms
also were used to cure livestock (Denisova, 1998).
Various volumes as the materia medica compiled by Li Shi-Zhen of the
Ming Dynasty highlighting more than 20 mushrooms (Bensky and Gamble, 1993),
now totals around at least 270 species of mushroom for various therapeutic
properties (Ying et al., 1987). Live ethnomycological practices in India (Natrajan et
al 2006) spanning from “Phanasomba” under the Ayurvedic regime to other
ethnomycological practices from central India (Vaidya et al., 2000; Harsh et al.,
1999; Rai et al., 1993), calls for a strategic investigations evolving from
ethnomycological practices to pharmacological evaluations.
1.3 Commercial scenario of medicinal mushrooms
The value of medicinal mushrooms along with their derivative dietary supplements
on global scale had increased 5 folds from US $1.2 billion in 1991 (Chang, 1996)
to, a considerable US $6 billion in 1999 (Wasser, 2000). The total global
production of edible and medicinal mushrooms escalated from 1.2 million tons in
1981 to an estimated 7 million tons in 1999 and approximately 9.9 million tons in
2004 (Casey, 2008). Thus is almost two decades the global production of
mushrooms increased c.a. eight times.
In 2004, the estimated value of wild edible mushroom gathering was $2
billion (Boa, 2004). In Washington, Oregon and Idaho sales reached $41.1 million
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INTRODUCTION
Chapter-1 in 1992 (Schlosser and Blatner, 1995). Trade of species like Cantharellus
formosus, C. subalbidus, T. magnivelare and Morchella spp. is an alternative
activity that complements local earnings, in the US Northwest, where the wood
industry is restricted (Pilz et al., 1999).
USA alone produced around 400,000 tons of Agaricus species in 2006
fetching $915 million that was 8% more than the previous crop year. Import of
mushrooms witnessed a 30% increase from the year before at $236 million for the
first 10 months of 2007. Though the speciality or medicinal mushroom accounted
for $40 million of the total in 2006, the initial leap was 400% from 2 to 8 million
pounds in a single crop year. The medicinal ones are catching up at a fast pace
as the bulk sales of Agaricus blazei of Torrance Ltd. alone has shot up 300%
within 2003 and 2007 (Casey, 2008).
Recognition of polysaccharides from mushrooms as anticancer agents,
other constituents exhibiting antioxidants, anti-hypertensive, cholesterol-lowering,
liver protection, anti-fibrotic, anti-inflammatory, anti-diabetic, anti-viral and anti-
microbial like activities, has overtly primed its potential as dietary supplements
(Zjawiony, 2004). They are designed to supplement the human diet, not to be
used as a regular food, by increasing the intake of bioactive compounds for the
enhancement of health and fitness. While more than 600 mushroom species have
revealed immune stimulation effects, commercial focus is still on medicinal
mushrooms like Grifola frondosa, Lentinula edodes, Ganoderma lucidum,
Coriolus versicolor, Agaricus blazei, Cordyceps sinensis, Hericium erinaceus and
Schizophyllum commune (Casey, 2008). US diet-supplement sales moved from
US$3.3 billion in 1990 to US$ 14.0 billion in 2000 (Zeisel 1999). Commercial
interest on "mushroom nutriceuticals" compounds that is used in the prevention
and treatment of various human diseases is increasing dramatically (Chang and
Buswell, 1996). The focus is majorly on the following species with specific
therapeutic potentials (Francia et al., 1999).
Total cholesterol reduction: Auricularia auricula-judae, Cordyceps sinensis,
Ganoderma lucidum, Grifola frondosa, Pleurotus ostreatus, and Tremella
fuciformis
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INTRODUCTION
Chapter-1 Low-density lipoprotein reduction: Auricularia auricula-judae and Tremella
fuciformis
Triglyceride level reduction: Cordyceps sinensis, Grifola frondosa, and Lentinua
edodes
Platelet binding reduction: Auricularia auricula-judae, Calyptella sp., Ganoderma
lucidum, Kuehneromyces sp., Neolentinus adhaerens and Panus sp.
Blood pressure reduction: Ganoderma lucidum, Grifola frondosa and Tricholoma
mongolicum
Glycemia reduction: Agaricus bisporus, Agrocybe aegerita, Cordyceps sinensis,
Tremella aurantia, Grifola frondosa and Coprinus comatus
Grossly speaking these species accounted for a US$3.6 billion industry in
1994 (Chang, 1996) and in 1995 G. lucidum alone accounted for a sale of about
US$1,628.4 million. The market values of the mushroom products were estimated
to be US$350 million in China, US$600 million in Korea, US$300 million in Japan,
US$215 million in Taiwan, US$91.2 million in Malaysia, US$60 million in Hong
Kong, US$2.2 million in Singapore and US$10 million in other countries (Chang
and Buswell, 1999).
The output of China’s edible mushroom increased from 1000 million
kilogram in 1978 to 14.7 billion kilogram to 2006, which is 3 times in less than 30
years accounting for 70% of the worlds’ total (Ziqiang, 2009). There was a
phenomenal increase in Chinese edible mushroom export (1.121billion dollar) in
2006, which escalated to 1.45 billion in 2007 and then 1.424 billion in 2008 (Hui,
2009). But this plummeted under the influence of the economic meltdown that
decreased the demand of medicinal and edible mushrooms by 40 – 20% (Ziqiang,
2009).
1.4 Natural products in drug discovery
Ethnopharmacological studies are generally based on anthropological
appropriations of natural resources that are propagated across several
generations endowing it traditionality, which if delved deeper regarding its mode of
actions may result in discovery of novel medicines (Patwardhan, 2005).
NAPRALERT a database withhold above fourteen thousand ethnomedical
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INTRODUCTION
Chapter-1 species which is only about 5% of the total estimated biodiversity. On the other
hand only 42% of the reported species are bioprospected leaving a large room for
exploration (Cordell and Quinn-Beattie, 2005). In addition to this one-half of the
anti-cancer drugs developed since 1960 (Kim and Park, 2002), and over 100
other successful pharmaceuticals (Farnsworth, 1994) are from natural resources. A recent survey revealed that 61% of the 877 drugs introduced worldwide
can be traced to or were inspired by natural products (Rouhi, 2003a). Natural
product drug discovery plummeted post combinatorial chemistry (Cseke et al.,
2004), which has given moderate outputs. The number of new drugs entering the
market has dropped by half, a figure of which the large pharmaceutical
corporations are painfully aware. Of the roughly 3,50,000 species of plants
believed to exist, one-third of those have yet to be discovered but at the same
time, habitat loss is the greatest immediate threat to biodiversity (Rouhi, 2003b).
Global sales of prescription pharmaceutical products are estimated to
exceed $330 billion and 57% of the top 150 prescription drugs contain active
ingredients that are pure natural products, synthetic derivatives or chemical
analogs of natural products (Grifo et al., 1997). Contradictorily the innate value of
such natural resources as plant, animal, and microbial products directly used in
the manufacture of prescription pharmaceuticals is estimated to be less than $12
billion (Ortega, 1998). Biodiversity is also a source of novel compounds for the
discovery of new drug leads, and pharmaceutical companies annually spend more
than $45 billion on research (Mathieu, 1998). But screening of natural and
synthetic compounds accounts for less than 12% of the research expenditures
because most of these resources are spent on equipment and manpower costs
rather than acquisition of compounds (PhRMA, 1999).
Skin care products containing biologically derived antioxidant, analgesic,
antibacterial and anti-inflammatory agents are a growing segment of this market.
One study estimated US sales of naturally derived personal care products to
account for $2.5 billion of the $28 billion US market. But, the value of the
biological source material used in these products was estimated at less than $500
million (Artuso, 2002).
About 60% of the drugs that are now available-including household names
such as artemisinin, camptothecin, lovastatin, maytansine, paclitaxel, penicillin,
reserpine and silibinin-were either directly or indirectly derived from natural
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INTRODUCTION
Chapter-1 products (Newman, 2008). As estimated by the World Health Organization almost
80% of the people rely mainly on traditional medicines for their primary health
care (Farnsworth et al., 1985). The continuum of new chemical entities (NCEs)
comprised of 877 small molecules (1981-2002), of which 67% were formally
synthetic but 16.4% correspond to synthetic molecules containing
pharmacophores and 12% were actually modeled on a natural products leaving
behind only 39% as truly synthetic (Newman et al., 2000).
1.5 Ecological bioprospecting aspects of plant para sitic macrofungi make
way for ethnomedicinal rationales
The inhabited earth is flooded with all sorts of life forms that compete for
resources. Thus in order to occupy a particular ecological niche the organism is
ought to be loaded with arsenal of counteracting metabolites that facilitate its
establishment. Under the co-evolutionary phenomenon the plants that evolved
antimicrobials were able to defend themselves against pathogenic bacteria;
pathogens that evolved resistance mechanisms, such as multi drug resistance
pumps, were able to break plant defenses; in turn, plants that developed multi
drug resistance inhibitors had a significant evolutionary advantage (Li & Zhang,
2008). This was reestablished when highly potent antimicrobial drug of Berberis
spp. (Pepperidge bush) was found to be due to its antimicrobial agents. But there
was a drastic reduction in potency when administered in pure form, because the
crude form of extracts had multidrug-resistance (MDR) inhibitors such as 5’-
methoxyhydnocarpin (Stermitz et al, 2000). Thus unlike allopathic regime,
ethnomedicinal regimes do not administer highly purified botanicals. By
administering crude preparations the traditional practitioners have been able to
suppress resistance and even toxicity. Aligning our research on these lines the
stress was on characterizing the active fractions rather than purifying individual
molecules.
On another axis, according to the hypothesis of xenohormesis, the
common ancestor of plants and animals were able to synthesize a large number
of stress-induced secondary metabolites but animals and fungi that feed on plants
gradually lost the capacity to synthesize some of these low-weight molecular
compounds. But they retained the ability to sense these chemical cues, possibly
in order to detect when plants were stressed and gain an early warning of
changing environmental conditions (Howitz and Sinclair, 2008). Thus reception of
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INTRODUCTION
Chapter-1 several metabolites not produced became all the more important. A comparative
genomic analysis revealed that 70% of cancer-related human genes have
orthologues in Arabidopsis thaliana (Jones et al, 2008). This ensures the cross
reactivity of several plant metabolites that were originally produced to modulate
their own metabolism and eventually end up bearing therapeutic potentials.
Moreover certain multidrug resistance-like proteins that are used by Arabidopsis
to transport auxin have orthologues in humans that are crucial for the transport of
anti-cancer agents; auxin-distribution modulators such as flavonoids from
Arabidopsis can inhibit P-glycoprotein (MDR1) in various human cancer cells
(Taylor & Grotewold, 2005).
Thus by co-evolutionary principle the plant parasitic macrofungi are known
to successfully infest the host heart wood. In order to launch and succeed in such
an insurgence the macrofungi is expected to overcome several challenges put
forth by the host. Moreover, according to the xenohormesis theorem, several plant
receptors and targets that may be attended by the macrofungi may have
homology with human counterparts. This paves the way for the rationale and
professes the plausible therapeutic potential of several bioactivities of
macrofungal metabolites. There are several studies which are based on mycellial
extracts of these macrofungi, but certain secondary metabolites are only
biosynthesized only in the fruiting body stage. Hence mycellial extracts may not
contain these molecules which the macrofungi prodices to forcefully establish
itself as a pathogen. The xenohormesis hypothesis implies that these
pathogenesis related macrofungal metabolites that are used against the host
might have better chances to work in human or mammalian-based in vivo models.
This piece of work was thus based on these rationales and in order to strengthen
its foundation, ethnomycomedicinal practices were aimed at, which ensues
clinically validated practices.