The Croton megalocarpus plant belongs to the family Euphorbiaceae and is indigenous to East Africa being widespread in the mountains of Tanzania, Kenya and Uganda between the altitudes of 1300 and 2200 m in regions with annual rainfall between 800 and 1600 mm and average annual temperatures
varying between 11uC and 26 uC.23
It is a dominant upper canopy forest tree reaching heights of 40 m or more. Croton seeds contain approximately 32% oil
by weight.24The oil contains mainly C18 : 2 (72.7 wt%) and C18 : 1 (11.6 wt%).
The biodiesel yielded has cloud and pour points of 24 uC and 29 uC,
respectively, while its kinematic viscosity lies within the recommended standard value. This points to the viability of using croton biodiesel in cold
regions.23
8.2.7
Datura stramonium L.
Datura stramonium L. belongs to the family Solanaceae.25 It is native to
Mexico and grows wild in warm and temperate regions in almost 100
countries, where it is typically found along roadsides and in dung heaps.26It
grows in rich, light sandy soil or in calcareous loam and in open sunny areas, it can also grow in the shade and in a wide variety of climates (from humid to
arid) and soil conditions, although it is very sensitive to frost.25It forms a bush
with a height of approximately 0.3–1.5 m. It contains dangerous levels of deliriants and anticholinergic poisons such as atropine, hyoscyamine, and
scopolamine.27 The seeds contain 10.3–23.2 wt% vegetable oil.28,29 A
maximum fatty acid methyl ester yield (87%) and content of more than 98
wt% have been obtained.25It contains mainly linoleic acid (56.8 wt%) and oleic
acids (28.5 wt%). It possesses the kinematic viscosity 4.33 mm2s21and the cold
filter plugging point (CFPP) 25uC.
D. stramonium was used for its medicinal potential by the Arab physician
Avicenna in 11th Century Persia.30It has long been used as a herbal medicine
with narcotic, anodyne, and antispasmodic effects.31,32
8.2.8
Gossypium hirsutum L.
Gossypium hirsutum L. belongs to the Malvaceae family and is commonly
called cotton.33It is one of the second best potential sources for plant proteins
after soybean and the ninth best oil-producing crop.34,35 Cotton seed oil is
extracted from the seeds of the cotton plant after the removal of cotton lint and contains significant amounts of saturated fatty acids, palmitic acid (22–26%), stearic acid in smaller amounts (2–5%) as well as traces of myristic, arachidic and behenic acids, lesser amounts of monounsaturated fatty acids, oleic acid (15–20%) being the major species, accompanied by traces of palmitoleic acid and a majority of diunsaturated linoleic acid (49–58%) with traces of linolenic
kinematic viscosity, acid value, free and total glycerin compare well with
ASTM D-6751 and EN 14214 specifications.33
8.2.9
Hevea brasiliensis
Hevea brasiliensis belongs to the family Euphorbiaceae and is the primary source of natural rubber. It is found mainly in Indonesia, Malaysia, Liberia,
India, Sri Lanka, Sarawak, and Thailand.4The tree can grow up to 34 m in
height and requires heavy rainfall. Rubber trees yield a three-seeded ellipsoidal capsule, each carpel with one seed and the seeds are ellipsoidal, variable in size,
2.5–3 cm long, mottled brown, lustrous, weighing 2–4 g each.36The oil content
of the seeds, which may contain up to 17 wt% free fatty acids, ranges from 40 to 50 wt% and is high in unsaturated constituents such as linoleic (39.6 wt%),
oleic (24.6 wt%), and linolenic (16.3 wt%) acids.36 The physical properties of
the resultant rubber seed oil methyl esters include cloud point and pour point
values of 4uC and 28 uC, respectively, and a kinematic viscosity (at 40 uC) of
5.81 mm2s21. The filtered oil is used as a feedstock for biodiesel production.
8.2.10
Jatropha curcas L.
Jatropha curcas L. is a large or medium shrub tree, up to 5–7 m tall, has a life- span of up to 50 years, and belongs to the Euphorbiaceae family, native to tropical America but widely distributed in tropical and subtropical regions
throughout Africa, India and Southeast Asia.37 It can grow on well-drained
soils with good aeration and is a well adapted to marginal soil with low
nutrient content, shedding its leaves in the dry season.38,39It can grow under a
wide range of rainfall regimes from 250 to over 1200 mm per annum.39,40The
plantation spaces of 2 6 2, 2.5 6 2.5 and 3 6 3 m are reported to give larger
yields of fruit.41It bears fruits from the second year of its establishment, and
the economic yield stabilizes from the 4th or 5th year onwards. The fruit is a kernel which contains three seeds each and it gives about 2–4 kg seeds per tree per year however in poor soils, the yields have been reported to be about 1 kg
seeds per tree per year.42The oil yields are reported to be 1590 kg per hectare.
Production of the seeds is about 0.8 kg m22per year and the oil content of seed
ranges from 30 to 50% by weight and in the kernel from 45 to 60%. The fatty acid composition of jatropha classifies it as a linoleic or oleic acid type, which are unsaturated fatty acids therefore it has good low-temperature flow properties but not such good oxidation stability. The average production of jatropha oil on average soil is 1.6 million tons per hectare.
Fresh jatropha is a slow-drying, odorless and colorless oil and becomes yellow after aging. It is also known as Ratanjayot and physic nut. Jatropha oil
is considered a non- edible oil due to the presence of toxic phorbol esters.43,44
Jatropha curcas oil has been highlighted as a potential biodiesel feedstock among the non-edible oils. It satisfies all the biodiesel standards except the oxidation stability that is in the range of 2–4 h. Apart from being potential
feedstock in the production of biodiesel as a diesel substitute, jatropha oil has other uses such as producing soap and biocides (insecticide, molluscicide,
fungicide and nematicide).45
8.2.11
Maduca indica
Maduca indica commonly known as mahua or butter tree is a tropical tree belonging to the family Sapotaceae. It is approximately 20 m in height, found largely in the central and northern plains and forests of India, grows fast, possesses evergreen or semi-evergreen foliage, and is adapted to arid
environments.46,47 The medium-to-large deciduous tree is found abundantly
in most parts of the world.48The mahua tree starts producing seeds after 4–7
years and continues for up to 60 years with the yield of M. indica seeds varying
(5–200 kg per tree) depending upon the size and age of the tree.49 The kernel
constitutes about 70% of the seed and contains 50% oil.50 The fatty acid
composition of consists of both saturated (17.8–24.5% palmitic acid and 14– 22.7% stearic acid) and unsaturated fatty acids (37.0–46.3% oleic acid and
14.3–17.9% linoleic acid).51 The relatively high percentage of saturated fatty
acids results in relatively poor low-temperature properties.
8.2.12
Melia azedarach
Melia azedarach belongs to the family Meliaceae and commonly known as
syringa or Persian lilac. It is native to India, southern China, and Australia.4It
is a deciduous tree that grows to 7–12 m in height. The oil content of dried syringa berries is around 10 wt% and it is characterized by a high percentage of
unsaturated fatty acids such as oleic (21.8 wt%) and linoleic (64.1 wt%) acids.52
Saturated fatty acids such as palmitic (10.1 wt%) and stearic (3.5 wt%) acids are also present. The physical properties of biodiesel prepared from syringa oil
include a kinematic viscosity (at 40uC) of 4.37 mm2
s21, an iodine value of 127,
and a specific gravity of 0.894 g mL21.
8.2.13
Pongamia pinnata
Pongamia pinnata commonly known as karanja, pongam, and honge belongs
to the family Leguminaceae.53It is native to a number of countries including
India, Malaysia, Indonesia, Taiwan, Bangladesh, Sri Lanka and Myanmar. P. pinnata is a fast-growing medium-size (12–15 m height) leguminous tree having the ability to grow on marginal land and this tree has been also successfully introduced to humid tropical regions of the world as well as parts of Australia,
New Zealand, China, and the USA.54,55It requires an annual rainfall ranging
between 500 and 2500 mm. Pongamia also exhibits wide adaptation to various soil types and saline/alkaline conditions, is regarded as a drought-tolerant species, can be planted in degraded lands, wastelands, or fallow lands and is highly tolerant to salinity. However, the highest growth rate and yield of oil are
observed on well-drained soils with assured moisture.56P. pinnata bears flat- to-elliptical 5–7 cm long green pods which contain 1–2 kidney-shaped brownish red kernels and the yield of kernels per tree is between 8 and 24 kg, therefore, the tree has the potential for high oil seed production of about
25–40%.57Researchers have investigated the performance of CI diesel engines
with Pongamia biodiesel and concluded that pongamia biodiesel can be used as
an alternative fuel.58 The predominant fatty acid is oleic acid (51.8%) with
linoleic acid (17.7%), palmitic acid (10.2%), stearic acid (7.0%), and linolenic
acid (3.6%) also present.59
It is currently cultivated mainly for ornamental purposes due to its large
canopy and showy flowers.4Different parts of the plants such as the leaves,
roots and flowers are reported to possess medicinal properties.
8.2.14
Prunus sibirica L.
Prunus sibirica L., a member of the family Rosaceae and the genus Prunus, is a deciduous shrub native to temperate, continental, mountainous regions, which include Eastern Siberia, the Maritime Territory of Russia, eastern and southeastern regions of Mongolia, and northern and north-eastern regions of
China.60It is commonly known as Siberian apricot and can grow in temperate
climates and thrives with abundant solar radiation, at low temperatures, in strong winds, low rainfall and poor soil. It bears fruit in its 4th year and enters into the full bearing period in its 8th year. The seed kernel has a high oil
content (50.18 ¡ 3.92%), and the oil has a low acid value (0.46 mg g21) and
low water content (0.17%). The fatty acid composition of the Siberian apricot seed kernel oil includes a high percentage of oleic acid (65.23 ¡ 4.97%) and linoleic acid (28.92 ¡ 4.62%). The measured fuel properties of the Siberian apricot biodiesel, except CN and oxidative stability, conform to EN 14214-08 and ASTM D-6751-10, in particular, the cold-flow properties were excellent.
The traditional use of Siberian apricot focuses on its ecological benefits, such as water and soil conservation, windbreak, sand fixation, environmental
protection and greening.61 The seed kernel oil can be used for edible oils,
lubricants, cosmetics, surfactants, and in the prevention of cardiovascular
diseases and the lowering of plasma cholesterol levels.62
8.2.15
Putranjiva roxburghii
The Putranjiva roxburghii tree belongs to the family Euphorbiacae and is also called the lucky bean tree. These plants are abundantly available in the Tropic
of Cancer.4Putranjiva oil is yellow in color, highly pungent, volatile and rich
in oleic acid. The composition of its oil is C14 : 0; 0.03%, C16 : 0; 10.23%, C16 : 1; 0.07%, C17 : 0; 0.07%, C17 : 1; 0.02%, C18 : 0; 10.63%, C18 : 1; 48.65%, C18 : 2; 27.50%, C18 : 3; 0.87%, C20 : 0; 1.05%, C20 : 1; 0.30%, C22 : 0; 0.24%, C22
: 1; 0.03%, and C24 : 0; 0.31%.4The viscosity of the oil is 37.6 cSt at 40uC