1. INTRODUCTION - Shodhgangashodhganga.inflibnet.ac.in/bitstream/10603/96409/6/07_chapter 1.pdf · Promotion of crops such as sugar cane, beet sugar, sweet sorghum, cassava etc as

Molecular studies on Azadirachta indica

Department of Biotechnology, Gulbarga University, Kalaburagi.

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1. INTRODUCTION

India is one of the fastest developing countries with a stable economic growth,

which multiplies the demand for transportation in many folds. Fossil fuel

consumption is directly proportionate to this demand. India depends mainly on

imported fuels due to lack of fossil fuel reservoirs and it has a great impact on the

economy. Fast depletion of fossil fuels demands an immediate and urgent need for

extensive research so that some viable alternative is obtained and sustainable energy

demand with less environmental impact is met. The major environmental concern, as

expressed in an IPCC report is most of the observed increase in globally averaged

temperatures since the mid 20th century is due to the observed increase in

anthropogenic greenhouse gas concentrations (IPCC, 2009).

The major percentages of energy used in the world today are being generated

from fossil fuel sources. These fossil fuels are non-renewable resources that take

millions of years to form and their reserves are being depleted faster than they are

being regenerated. They are the major contributors and sources of greenhouse gases,

air pollution and global warming. Some of the emissions generated from these fossil

fuels are CO, CO2, NOx, SOx, unburnt or partially burnt hydrocarbon and particulate

(Ndana et al., 2011). Non-renewable fossil fuels are a limited resource that supplies

nearly 90% of the world‟s energy demand. Sustained economic growth in India

desires for similar trends, especially the increase in global energy consumption

(Fig.1). Although it is much debated as to whether substantial oil reserves lie

undiscovered, inaccessible or environmentally hazardous to recover. It is widely

accepted that the rate of consumption will continue to increase.



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Fig 1: World marketed energy consumption 1980-2030

(Adapted from www.eia.doe.gov/iea)

Another concern is advocated by the peak oil theory which predicts a rising

cost of fossil fuels caused by a severe shortage of petroleum reserves underground

during an era of growing energy consumption. According to the peak oil theory, the

demand for oil will exceed the supply, and the gap between the demand and supply

will continue to grow. This could cause a growing energy crisis starting between 2010

and 2020. However, the crisis has not yet come and it may be delayed further. The

reason is that the peak oil theory did not take into consideration the growing

technological developments in the energy sector (Fusco, 2013). Since the majority of

the known petroleum reserves are located in the Middle East, Asia, there is a general

concern that the fuel shortage worldwide could intensify the unrest in this region. This

rate of depletion and environmental issue is seriously calling for an alternative.

An alternative fuel also known as a non-conventional fuel, is any material or

substance that can be used as a fuel other than conventional fuels. Conventional fuels

include fossil fuels (petroleum oil, coal, propane and natural gas) and also nuclear



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fuels such as uranium in some instances. A host of alternative fuels has already been

identified, and these include biodiesel, bio-alcohol (methanol, ethanol and butanol),

hydrogen, non-fossil methane, non-fossil natural gas, vegetable oils and other fuels

derived from biomass sources. Among all those alternative fuels, biodiesel is the most

promising, popular in the transport sector and other CI engine applications.

1.1 Demand of crude oil in India

Currently India is the third largest oil consumer in the world behind the US,

China and Japan. The US will continue to be the world‟s biggest oil consumer but

with almost no demand growth. The US consumed 18.21 million bpd of oil in 2012,

projected to rise 19.23 million bpd in 2020 before falling to 18.97 million bpd in 2025

and to 18.42 million bpd in 2040. China oil consumption is projected to rise from

10.36 million bpd in 2012 to 15.70 million bpd in 2025 and 20.48 million bpd in

2040, posting a compounded annual growth rate of 2.5%.

India‟s oil consumption growth rate from 2012 to 2040 will be highest in the

world with a 3% compounded annual growth rate. Its oil consumption, according to

EIA, will reach 6.11 million bpd in 2030 and 8.33 million bpd in 2040. As much as

80% of India‟s oil need is met through imports. China‟s gross domestic product

(GDP) is roughly 4.5 times more than that of India and the US gross domestic product

almost nine times that of India. India had in 2013 overtaken. Japan is the world‟s

third-biggest crude oil importer. It imported 3.86 million bpd of crude oil, nearly 6%

higher than Japan‟s customs-cleared imports of 36,48,372 bpd. The International

Energy Agency estimates that India will become the world‟s largest oil importer by

2020 (Fig. 2).



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Fig 2: Oil demand

The rapid increasing demand for crude oil coupled with the increase in fuel

demand has forced the countries to look for an alternative to conventional fuels. The

biodiesel production from a non edible seed plant like neem, pongamia, mahua, etc.

are being considered as an indigenous source of oil for biodiesel production. Once the

oil resources starts to available in the country, the availability of biodiesel as

substitute to the diesel fuel will increase and dependency on oil import would reduce

thereby making the country self sufficient in fuel supplies.

1.2 Biofuel policy in Karnataka

Karnataka is the India‟s eighth largest state in geographical area covering 1.92

lakh Sq.Km and accounting for 6.3% of the geographical area of the country.

Agriculture is the major occupation for a majority of the rural population in

Karnataka. The agricultural sector of Karnataka is characterized by vast steppes of

drought prone region and sporadic patches of irrigated area. Thus, a large portion of

agricultural land in the state is exposed to the vagaries of monsoon with severe agro-

climatic and resource constraints. Agriculture employs more than 60% of Karnataka‟s

workforce.



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Karnataka has over 13.5 lakh hectares of such lands and the same can be

utilized for growing biofuel species (Table 1). Village tank fore shore and bunds,

degraded forest lands other government marginal lands, institutional lands left

unproductive, village common lands, bunds of the farmers land can be utilized for

raising biofuel species. The implementation of all programs will be with the total

involvement of farmers, landless labourers, NGOs, VFCs and TUGs. Entire program

will be implemented without affecting the food security of the state.

Karnataka took the lead in constituting the Biofuel Task Force on 12th

September, 2008 for effective planning and implementation of the biofuel programs.

The task force was entrusted with the responsibility of advising the Government and

to create an enabling atmosphere in the state. The Karnataka state has already adopted

the Karnataka Biofuel Policy from 1st March, 2009.

In order to take forward the biofuel activities, the state government has

constituted a permanent body by converting the Biofuel task Force into Karnataka

State biofuel Development Board as a society registered under Registrar of Society

and fully funded by Government of Karnataka. Karnataka state biofuel development

board (KSBDB) constituted under the rural development and panchayat raj

department is taking forward the biofuel policy objectives of the state with effect from

6th

decemeber 2010 in Karnataka state.

1.2.1 Biofuel objectives of KSBDB

Help government design and adopt biofuel programs.

Implementation of such programs in tune with the policy.

Identification of suitable land for raising biofuel crops.

Selection of suitable mix of plant species for different geo-climatic

conditions.



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Raising of quality seedlings through self help groups (SHGs) village,

forest, committees (VFCs)

To ensure total participation of the committees.

To create awareness among the farmers to adopt biofuel activities for their

additional income.

To provide right impetus to ethanol production and usage.

Promotion of crops such as sugar cane, beet sugar, sweet sorghum, cassava

etc as feedstock for ethanol production.

Setting up of information and demonstration centres for biodiesel

production.

Establishment of seed collection networks.

Programs for value addition and usage of value added products in rural

areas.

Establishment of clonal orchards in different regions across the state.

Encouraging various research activities in the entire biofuel value chain

involving Universities and research organizations.



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Table 1: Biofuel Plants in Karnataka State

Biofuel

plants Neem Pongamia Simarouba Mahua Jatropha

Uses

Biofuel,

Medicine,

Biopesticide,

Oil cake,

Manure,

Agricultural

equipment

Biofuel,

Manufacture

of soap,

Leather

tanning, Oil

cake, Manure,

Medicine,

Biopesticide

Biofuel,

Medicine,

Edible oil,

Biopesticide,

Oil cake,

Manure

Biofuel,

Medicine,

Oil cake,

Manure,

Agricultural

equipment

Biofuel,

Medicine,

Biopesticide

Starts

yielding 5 Years 5-6 Years 5-6 Years 10 Years 3 Years

Yield of

seeds 15-35 Kg 15-40 Kg 10-25 Kg 10-40 Kg 2-4 Kg

Oil

Content 28-35% 30-35% 40-50% 30-35% 30-35%

Seed cost

per Kg 12/- 16/- 11/- 10/- 10/-

Harvesting

period June-August March-May Feb-April June-August Aug-Oct.

1.2.2 Hyderabad Karnataka Region

Hyderabad Karnataka region is situated in the north eastern part of the

Karnataka state and falls within the geographical region of north maiden (Fig. 3). It

spreads between 140 60‟ to 18

0 30‟ Northern latitude and 75

0 60‟ to 77

0 70‟ Eastern

altitude (Brisbhasi, 2001). The region is bound on the north by Sholapur, Nanded and

Usmanabad districts of Maharashtra State and on the east by Nizamabad, Medak,

Mahaboob Nagar, Rangareddy districts of Andhra Pradesh, in the south by Karnool

district of Andhra Pradesh and Chitradurga, Devangere districts of Karnataka state in

the west by Bijapur, Bagalkot, Gadag and Haveri districts of Karnataka state.

The Hyderabad Karnataka region covers the area of 44138 Sq.Km. This is

account for 23.12% of the total geographical area of the Karnataka State. At presently

it is consist of six districts i.e., Bellary, Bidar, Gulbarga, Yadgir, Raichur and Koppal.

The Karnataka State Biofuel Development Board has identified the Hyderabad



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Karnataka region as the best site in the State, with its vast wastelands, for the

cultivation of biofuel plants to increase its production manifold (Table 2).

Fig 3: Administrative Map of Hyderabad Karnataka Region

Table 2: Wastelands of Hyderabad Karnataka region

HK Region Wasteland (Hectares)

Bidar 19,127

Gulbarga 63,155

Yadigir 63,155

Raichur 20,084

Bellary 53,477

Koppal 16,627



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1.2.2.1 Physiographic of HK Region

Physiographical, the Hyderabad Karnataka region forms the part of two well

defined physiographic region of Karnataka state.

Northern part of Karnataka Plateau

The northern Karnataka plateau comprises the districts of Bidar and Gulbarga.

It is largely composed of Deccan trap. It represents a monotonous treeless extensive

plateau landscape with a general elevation of 300 to 600 mts. From the mean sea level

this region is largely covered with the rich black cotton soil.

Central Karnataka plateau

The central Karnataka plateau comprises of the districts of Raichur, Koppal

and Bellary. The region represents the transisnal surface between the Northern

Karnataka plateaus with relatively higher surface. By and large this region represents

the area of Tungabhadra basin. The general evaluation varies between 450 to700 mts.

from the sea level.

1.2.2.2 Soil

The soil condition in Hyderabad Karnataka region varies from district to

district. Major portion of Gulbarga and Bidar districts consists of deep black soil, few

parts of Bidar district i.e., Humanabad, Basavakalyan, Bidar talukas have laterite soil.

On the other hand the districts of Raichur, Koppal, Yadgir and Bellary districts are

covered by the reddish. Sandy soil, the light green loamy soil and there reddish drown

soil. The soil and climate conditions are very district to district in the H.K. region.

1.2.2.3 Climate

The climate of the H.K. region in general is characterized by dryness for the

major part of the year and a very hot summer. The year may be divided broadly into

four seasons. The hot season begins by the middle of February and extends to the end



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of May. The south-west monsoon season is from June to the end of September.

October and November are post monsoon and the period from December to the

middle of February is the cold season. The region receives rainfall both from south-

west and North West monsoons. However, the mean rainfall in the region is very

scant at 692 million meter in a year.

1.3 Biodiesel in India

The consumption of diesel fuel in India is approximately six times that of

gasoline fuel, as shown in Table 3 (BPC, 2013). The table predicts a rising cost of oil-

derived fuels caused by severe shortages of oil because of growing energy demand.

Renewable fuels, particularly biodiesel, should get more attention in India.

Researchers are trying to find several ways to make biodiesel from different feedstock

such as edible oil, non-edible oil, waste vegetable oil, algae, animal tallow and fats,

etc.

Table 3: Demand for gasoline and diesel in India.

Year Gasoline demand (MMT) Diesel demand (MMT)

2001–2002 7.07 39.81

2002–2003 7.62 42.15

2003–2004 8.20 44.51

2004–2005 8.81 46.97

2005–2006 9.42 49.56

2006–2007 10.07 52.33

2011–2012 12.85 66.90

The transesterification process, employed to manufacture biodiesel from raw

feedstock, yields a byproduct glycerol, which has many applications in the

pharmaceutical, cosmetics and food industries. Sharma and Singh in 2010 produced

biodiesel from non-edible feedstock such as Karanja, Mahua and a hybrid mixture

(50:50 v/v) of the two. Saka and Kusdiana in 2011 produced biodiesel from rapeseed

vegetable oil. Venkanna and Reddy in 2009 produced biodiesel from Calophyllum



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Inophyllum Linn oil. Ghadge and Raheman in 2005-06 produced biodiesel from

Mahua oil.

Biodiesel produced from different sources, may be considered supplementary

fuels to the diesel fuel in CI engine applications. In addition, it also promises

employment to rural people through the opportunities of cultivation of oil bearing

plants, and this may help to improve the domestic economy. Biodiesel is a clean

burning fuel, and it can be produced from 100% renewable resources (Minnesota,

2013). Several experimental studies (Palit et al., 2011; Agarwal and Das, 2000; Shaoo

and Das, 2009; Misra and Murthy, 2011) available in the literature have shown that

biodiesel and biodiesel-diesel blends reduce smoke opacity, emission of particulate

matter, unburnt hydrocarbon and carbon monoxide as well as life-cycle carbon

dioxide emissions. However, the emission of nitrogen oxides increases to some extent

with the use of biodiesel as fuel. However, the NOx emissions can be reduced by the

use of any post-combustion techniques such as exhaust gas recirculation and catalytic

conversion. As biodiesel contains about 11% excess oxygen, the calorific value is

lower than diesel, but it enhances the combustion process. The peak pressure rise after

TDC with biodiesel makes the combustion process safer and more efficient. Another

advantage is the shorter ignition delay of biodiesel, which results in a decrease in

maximum heat release rate.

Biodiesel does not contain petroleum, but it can be mixed with petroleum and

a biodiesel blend thus made it can be used in a number of vehicles. Biodiesel is

biodegradable and nontoxic. It has even been claimed to be less toxic than common

salt. Biodiesel is made from oil through a process called transesterification. This

process involves removing the glycerin from the oil or fat. Biodiesel is free from

some environmentally harmful substances such as sulfur and aromatics that are found



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Fig 4: Transesterification reaction for biodiesel production

in the traditional diesel fuels. The overall reaction of the transesterification process is

shown in Fig 4.

1.4 Biofuel policy in India

The Government of India (GOI) approved the National Policy on Biofuels on

December 24, 2009. The policy encourages use of renewable energy resources as

alternate fuel to supplement transport fuels and had proposed an indicative target to

replace 20% of petroleum fuel consumption with biofuels (bioethanol and biodiesel)

by end of 12th Five-Year Plan (2017).

Indian Governement has adopted several policies in order to strengthen the

biofuel sector. It starts with the selection of appropriate feedstock having a relatively

higher oil yield and higher availability. The selection of the feedstock should be made

in such a manner so that the cultivation throughout the country with minimum cost is

possible. It also includes the identification of lands and seeds and the task of

motivating farmers for cultivating the biodiesel feedstock, mainly the non-edible plant

like Neem. So there is a long chain of activities that starts with the identification of oil

seeds, extraction of oil from the seed, transesterification of the raw vegetable oil for

the production of biodiesel, transportation of biodiesel to the oil depot, making blends

with mineral diesel, and finally, distribution to retailers. Table 4 (Kumar and Sharma,

2011) and Table 5 (Borugadda and Goud, 2012) estimated the yield of oil seed and

the potential of non-edible oil seed, respectively, in the Indian scenario. It can be seen



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from Table 4 that the oil yield of neem per hectare of land is highest among the

prospective non-edible oil seeds. It is quite interesting to note from the data in Table 5

that although neem has higher potential, it is found to be very attractive in the sense

that it can grow in adverse agro-climatic conditions throughout India. For the above-

mentioned reasons, neem has been identified as one of the most acceptable another

potential biodiesel-producing feedstock in India.

Table 4: Estimated yield of non-edible oil from different plants

Name Plant type Plant part Oil yield (Kg/ha)

Azadirachta indica (Neem) Tree Seed 2670

Jatropha curcas (Jatropha, Ratanjyot) Tree/Shrub Seed 1900-2500

Pongamia pinnata (Karanja) Tree Seed 225-2500

Ricinus communis (Castor) Tree/Shrub Seed 450

Table 5: Potential non-edible oil seed plants in India

Name Distribution Potential (metric tons/annum) Oil (%)

Neem All over India 5,00,000 34-45

Jatropha All over India 15,000 40-45

Karanja Maharastra, Karnataka, Assam 2,00,000 30-40

Castor All over India 7,90,000 46-55

1.4.1 Salient Features of Biofuel policy

An indicative target of 20% blending of biofuels both for biodiesel and

bioethanol by 2017.

Biodiesel production from non-edible oilseeds on waste, degraded and

marginal lands to be encouraged.

A Minimum Support Price (MSP) to be announced for farmers producing

non-edible oilseeds used to produce biodiesel.



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Financial incentives for new and second generation biofuels, including a

National Biofuel Fund

Biodiesel and bioethanol are likely to be brought under the ambit of

“declared goods” by the Government to ensure the unrestricted movement

of biofuels within and outside the states.

1.5 Biodiesel

Mix of fatty acid methyl esters (FAME) made from a renewable biological

source such as non edible vegetable oil or used animal fat and algae is called

biodiesel. Biodiesel is simple to use as it requires no major modifications. It is also

non-toxic, biodegradable and free of sulfur and aromatics. Biodiesel can be produced

by different methods of esterification, though most follow a similar basic approach

and then retreated to transform, free fatty acids into biodiesel. FAME can be produced

by different methods of esterification, in which the oil is first filtered to remove water

and contaminants and then retreated to remove or esterified to transform, free fatty

acids into biodiesel. Following pre-treatment, the oils are mixed with methanol and a

catalyst (NaOH or KOH) to transesterify the triglycerides into FAME and glycerol.

The glycerol can then be separated and the FAME used as biodiesel.

The transesterification is not new and has been practiced since the 1800s when

it was used to produce glycerin for soaps. The use of vegetable oils in transport is also

not new. More than a century ago Rudolph Diesel, the inventor of the diesel engine

first powered his engine with peanut oil. It was not till the 1920s when petrol-diesel

became readily available that biodiesel went out of favor. Biodiesel is the only biofuel

for which there is a strong market demand at present. The temporal and spatial

flexibility in biodiesel production due to the variety of feedstock‟s available is a major

strength. Most countries in the Americas and Europe are self sufficient in their



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production of edible oil, which is generally surplus to their requirements. This is why

most of Germany and France produce biodiesel from rapeseed oil while most of that

from the USA is derived from soya bean. Malaysia and Indonesia use coconut for

biodiesel synthesis. On the other hand, India does not produce enough quantity of

edible oil and hence proposes the use of non-edible oilseed crops such as Azadirachta

indica, Pongamia pinnata, etc. are the alternative sources. The list of alternative

oilseed plants can be narrowed further to few useful plants according to their oil

productivity per hectare; potential economically useful by by-products; growth habit

(tree or shrub); water and the need for plant protection.

When biodiesel is considered, the compound of interest is on oils containing

triacylglycerols (TAG) that consist of three fatty acids esterified to a glycerol back

bone (Chisti, 2007; Sivakumar et al., 2010). Triacylglycerols can be either used

directly or after conversion to fatty acid methyl esters (FAME) as biodiesel,

depending on the fatty acid composition (Barnwal & Sharma, 2005; Merchant et al.,

2012; Sivakumar et al., 2010). Oils that are characterized by short chain fatty acids

with carbon chain lengths between 8 and 14 carbons have the potential for direct use

as liquid fuel, therewith reducing costs in downstream processing (Sivakumar et al.,

2010). TAGs with longer fatty acids with up to 18 carbons can be also used as biofuel,

but require prior processing into FAME (Sivakumar et al., 2010). Several vegetable

oils as derived from canola, palm and soybean contain high contents of C16 and C18

fatty acids and were subject to intense investigations of their fuel properties (Knothe,

2008).

For the generation of biodiesel these oils are transesterified to methyl esters, a

process catalyzed by acids, alkalis or lipase enzymes, which releases glycerin as a

byproduct (Barnwal & Sharma, 2005; Chisti, 2007; Nigam & Singh, 2011). The



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conversion of the original vegetable oil to biodiesel reduces the viscosity as well as

the molecular weight and opens the possibility of blending with conventional fuel in

any proportion (Barnwal & Sharma, 2005). A further possibility of conversion of oils

into liquid fuel can be found within the hydrogenation of vegetable oils as performed

for NEXBTL (Aatola et al., 2009; Nigam & Singh, 2011). Instead of fatty esters,

hydrocarbons are generated within a process where oxygen is removed from lipids

using hydrogen, without the need of additional chemicals (Aatola et al., 2009). Since

the term “biodiesel” is reserved for fatty acid methyl esters, hydrotreated oils are

therefore known as “renewable diesel fuels” (Aatola et al., 2009). However, the

required equipment is rather complex as well as an additional source of hydrogen is

needed (Nigam & Singh, 2011). Important points that need consideration when fatty

acid derived compounds are intended for biofuel applications include oxidative

stability, which is promoted by a high degree of saturation and cold flow, which

generally increases with the degree of unsaturation (Chisti, 2007 and Knothe, 2008).

In addition, it was recently proposed that optimally a biodiesel fuel should consist of

only one major component in high concentration, though mixtures might be also

acceptable (Knothe, 2008). Biodiesel is currently produced, relying principally on

canola, sunflower, soybean and palm oil as feedstock (Nigam & Singh, 2011;

Sivakumar et al., 2010; Srirangan et al., 2012). When compared to ethanol, the use of

TAG for a liquid biofuel generation has several advantages as it exhibits usually a

better energy balance and can be used directly without engine modifications

(Merchant et al., 2012; Sivakumar et al., 2010; Srirangan et al., 2012).



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1.6 Neem oil for Biodiesel

Neem (Azadirachta indica A. Juss) is a native Indian tree well known for its

medicinal features. Most of the parts such as leaves, bark, flower, fruit, seed and root

have applications in the field of medicine (Muthu et al., 2010). It is an evergreen tree

related to mahogany, growing in almost every state of India, South-East Asian

countries and West Africa (Munoz et al., 2007). It grows in drier areas and in all

kinds of soil. It contains several thousands of chemicals which are terpenoids in

nature. A mature neem tree produces 30 to 50 Kg fruit every year and has a

productive life span of 150 to 200 years (Ragit et al., 2011). It has the ability to

survive in drought and poor soils at a very hot temperature of 440C and a low

temperature of up to 40C (Karmakar et al., 2011), and its high oil content of 39.7 to

60% (Martin et al., 2010).

Features of Neem

Scientific classification

Kingdom - Plantae

Division - Magnoliophyta

Class - Magnoliopsida

Order - Sapindales

Family - Meliaceae

Genus - Azdirachta

Species - Azdirachta indica

The neem seeds are of medicinal value, but not used 100%. The remaining

seeds out of those used for medicine go waste. When these seeds are collected,

crushed into oil and the oil used as the source of biodiesel, the beneficiaries are the

rural population. Neem biodiesel could be used to run I.C engines and produce

electricity (Vijaya et al., 2015). Neem oil is available in India at minimum cost as



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India is one of the largest producers of neem oil. The amount of oil obtained from

neem seeds is 39.7 to 60% (Martin et al., 2010).

Neem oil contains certain acids, which are conscientious for burning of the oil.

The amount of fatty acids present in the neem oil is the main reason for the

conversion of biodiesel from it. As the fatty acid content in it increases, the

production of the biodiesel decreases. The fatty acid contents of neem oil and their

composition are listed in Table 6. Neem oil has a greater percentage of oleic acid

(Heydarzadeh et al., 2010). The number of carbon atoms and the number of double

bonds are different for different acids.

A



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Fig 5: Neem; A – Neem Tree; B – Neem Flowers; C – Neem Seeds



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Table 6: Composition of neem oil

Acid Name Lipid numbers Composition range

Linoleic acid C18:2 2.3-15.8%

Oleic acid C18:1 49-62%

Palmitic acid C16:0 13.6-16.2%

Stearic acid C18:0 14.4-24%

Alpha-linolenic acid C14:0 0.2-2.6%

1.7 Neem - A Wonder Tree

The neem has now been universally accepted as a “wonder tree” due to its

multitude of uses (Dhaliwal et al., 2004). Neem wood is moderately heavy, stable and

resembles mahogany in appearance. In its strength properties, it resembles teak but is

more resistant to shock. It is straight grained and seasons easily except for end

splitting. The wood is moderately resistant to fungi and repugnant to most borers, but

difficult to impregnate with preservatives (Lemmens et al., 1995). It is used for

making furniture, carts, axles, yokes, boards and panels, cabinets bottoms of drawers,

packing-cases, ornamental ceilings, ship and boat building, helms, oars, oil-mills cigar

boxes, carved images, toys, drums and agricultural implements (Forster and Moser,

2000). The neem tree provides good fuel wood and has long been used, in arid zones

of India (Tewari, 1992).

Neem bark contains tannins which are used in tanning, dyeing, etc.

Compounds extracted from neem bark are used in production of some dental care

products. Neem bark is also tapped for gum.

Neem seed pulp is useful for methane gas production. It is also useful as a

carbohydrate rich base for other industrial fermentations (Neem Foundation, 2007).

Dried flowers of the neem are either eaten raw or used as ingredients in curries and



21

soups or prepare as a fried dish in South India. They are useful in some cases of

dyspepsia and general weakness (Mitscher, 2005).

The leaves of the versatile neem trees also have many uses. Neem leaves are

not only useful for pest and disease control, they are also fed to livestock mixed with

other fodder in several feed in several parts of the country. Neem leaves are used in

some parts of India as fertilizer in rice fields (National Research Council, 1992). In

some countries, neem leaves are used as mulch in tobacco and tomato fields. Neem

leaves are spread over the plant roots to retain moisture, kill weeds, etc. Neem leaves

can also be used to protect stored woolen and silk clothes from insects (Glover and

Adams, 1990).

Neem oil contains several compounds which have proven medicinal an

agricultural use of high value. Neem oil is, however, not used generally for these

purposes. The most common use of neem oil is in soap production. This indicates the

vast scope for expanding neem oil production. The collection of neem seeds to be

supplied to the crushers can be important means of supplementary employment and

income for the poor household, especially for rural women, since the task of seed

collection is highly suited to them (Lauridsen et al., 1991). There are several other

uses of neem oil as well. Neem oil can be used as an illuminant. In India, neem oil is

widely burnt as fuel in lamps for lighting and repelling mosquitoes. Neem oil is used

for mosquito net impregnation which seems to be gaining popularity. Neem oil is also

useful for lubrication purposes (Neem Foundation, 2007).

1. INTRODUCTION - Shodhgangashodhganga.inflibnet.ac.in/bitstream/10603/96409/6/07_chapter 1.pdf · Promotion of crops such as sugar cane, beet sugar, sweet sorghum, cassava etc as

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