By
Dr. Mohammed S Berigari, Senior Soil and Environmental Scientist, USA, June 25/2012.
Jojoba, pronounced ho-ho-ba, is Simmondsia chinensis, a xerophyte, woody, and perennial evergreen shrub
native to the northern Mexico and southwestern Arizona and California in the
Sonoran Desert. Jojoba belongs to the family Simmondsiaceae. The plant can grow up to 5-meters in height with
leathery blue-green leaves about 2.5-cm in length. Female jojoba plants produce oval fruits that
open at maturity releasing 1-3 brown, peanut-sized seeds. The plant can live up to 200-years. Jojoba plants grow well in coarse textured
soils of marginal fertility due mainly to their deep roots. Jojoba plants need
less than one half the amount of water required by olive trees. Natural jojoba populations grow in areas
receiving 76-450-mm of rain annually depending on soil relief (topography) that
affects water runoff. The best jojoba plants observed, 5-m in height, were in
areas with 254-380-mm of annual precipitation.
Jojoba is tolerant to salinity, to drought, withstands hot summers, and
is a low labor intensive crop.
The Need for Finding a
Substitute for Sperm Whale Oil:
When the Sperm Whale was listed as endangered species, the US
and other industrial countries looked for alternative sources of its wax due to
its indispensable uses and applications.
Synthetic substitutes are difficult to produce, therefore, investigations
focused on natural sources. The Orange
Roughy fish makes similar oil, but it has been overharvested, thus, it could
not be relied on as a long term solution. With the enactment of the Endangered
Species Act for Sperm Whale, jojoba received serious attention in USA in the
early 1970’s. Jojoba seeds contain about
50% by mass of a light golden-colored liquid-wax similar in chemical
composition to the Sperm Whale oil, and it turned out to be a perfect
substitute for the liquid-wax of the Sperm Whale.
Jojoba Cultivation:
Irrigation systems are necessary to begin with jojoba
plantations whether by planting seeds or seedlings. The plants seem to do well after two years of
intensive watering in early winter and spring when jojoba plants use water efficiently
for optimum growth. This watering period is very suitable for farmers, as
jojoba water needs will not conflict with the watering requirement of
traditional crops. Under optimum conditions of soil, water, sunlight; the tap
root will grow 2.5-cm a day, and within two years (about 9.0-m) the roots should reach the underground water level to
enable sufficient growth for seed production without supplemental irrigation. Since,
new flowers develop in late summer, hence, midsummer irrigation in very dry
years would be beneficial for good flower production and good seed yield. Jojoba generally does not produce an
economical yield until the fourth or fifth year after planting.
At maturity a single plant can yield as much as 5-kg of
seeds. A yield of 3500-kg per hectare
(3000-pounds per acre) appears to be a realistic expectation from 9-10 year old
plantation.
Temperature may be the most critical factor in growing
jojoba. Flowers and terminal portions of branches of most jojoba plants would
be damaged by frost when atmospheric temperatures reach -5 to -6 ᴼC.
Jojoba shrubs with
proper pruning can form trees just like olive trees with rows of trees spaced
at 3-m apart for mechanized cultivation, weeding, and other operations. In Palestine
such practices are adopted and jojoba plantations appear very much like olive
orchards.
Propagation:
Jojoba can be propagated by seeds, rooted cuttings, and
tissue cultures. Single plant
variability in seed size, yield, morphology, and wax content is striking both
within and among natural populations. However, wax composition is extremely
uniform throughout the area of its adaptation which seems to depend on its
genetic makeup and not on other variations. The plants are dioecious, that is
there are male and female plants. It is
not possible to distinguish female plants from the male plants of jojoba before
flowering. In order to maximize production, it would be useful to plant rooted
cuttings from sexed plants that are known to be high producers or to have seeds
with high oil content. Rooting the cuttings requires some technical knowhow,
but it would be worthwhile to have a plantation with 90% to 95% female plants
and 10% to 5% male plants respectively to produce enough pollen to fertilize
all the female flowers.
Jojoba is currently grown
as an industrial crop in USA, Argentina, Australia, Mexico, India, Israel,
Jordan, Pakistan, and Palestine.
Various Uses of Jojoba
Oil:
Currently there are numerous uses for jojoba oil. They include cosmetics, lubricants for
delicate equipment such as watches, artificial hearts, but also for motors and
transmissions. Moreover, it is used as a
low calorie cooking oil that does not rancid, antifoaming agents in
fermentation processes, candle wax, polishes, coating of fruits and pills,
insulations for batteries and wires, varnishes and paints, detergents, plastics
and resins, leather softener, transformer coolant, and more.
Jojoba
oil has special and unique uses for treatment of human skin diseases and
cosmetic uses such as shampoos and creams for beautification of hair and face,
and prevention of facial and neck wrinkles. Jojoba oil is similar to the sebum
oil produced by human skin and is absorbed by human skin in few seconds without
leaving any residue. Moreover, jojoba oil use for cosmetics is superior and
distinctive over other plant seed oils, animal fats, and many synthetic
chemicalss which are added to cosmetics for their marketing purposes. And there is a justified trend worldwide for
preference of natural products because of the concern over introducing
carcenogens to humans by synthetic chemicals.
About 50-ml of jojoba oil(
boiling point 390 ᵒC) per liter of
automoible motor oil or transmission oil is used to extend the period for car
oil use to 20,000-km of driving before it has to be changed because of the high
boiling poit of jojoba oil. Therefore,
with the growing demand for huge amounts
of jojoba oil for lubrication industry, especially for automobiles and
airoplanes, even if vast areas of lands were planted with jojoba in various
parts of the world, the oil produced will not be enough to meet the demands of all
industrial uses.
Chemical
Composition:
Jojoba oil is a unique liquid-wax similar in composition to
the Sperm Whale oil. Chemically, jojoba
esters are a complex mixture of long chain unsaturated fatty acids and
unsaturated fatty alcohols each chain made up of 20-21-carbon atoms joined by
an ester bond to form linear chains of 42-carbon atoms, thus, the fatty acids
in jojoba wax are not 16-18-carbon atoms as is the case with fatty acids
commonly found in triglycerides of other plant seeds oils (Figure 1).
The
Prospects of Jojoba Crop Cultivation in Iraq:
With this background about jojoba as a
commercial crop grown in arid regions for production of its seeds that contain
about 50% by mass of a unique oil which is acually a liquid-wax that has
numerous cosmetic, medical, and industrial applications. It is a perfect substitute for the oil(wax) of
Sperm Whale, the endangered species.
Therefore, the prospects for success of
jojoba plantations in Iraq are high considering the climatic conditions and
widespread coarse textured soils with marginal fertility. Such prospects exist especially on the slopes
of Kurdistan hills and mountains where the annual rainfall is ≥ 250-mm, the temperatures
seldom reach -3 ᴼC, and where natural vegetation of trees and
shrubs is scarce or scattered. jojoba
evergreen plants beside adding beautiful scenery to the landscape, they also can
stablize soils against serious erosions in addion to their valuable seed products.
References
4. Tremper, Gary. 1996 . The history and promise of jojoba. Armchair World,
زيت الهوهوبا هو شمع سائل يستخلص من بذور (بندق)
الهوهوبا الجافة 60% من وزنها زيتاً، وإن ذلك الزيت الذهبي الصافي الذي ينتج من
عصر بذور الهوهوبا هو بالواقع ليس زيتاً بل شمعاً سائلاً. تركيب زيت الهوهوبا
الكيميائي يبين أنه لا يحتوي على جليسيرين الذي هو العمود الفقري لجميع الزيوت
النباتية والدهون. شمع الهوهوبا السائل يسمى زيتاً فقط لأنه سائل. فمن خواص زيت
الهوهوبا أنه إستر غير مشبع مكون من سلسلة مستقيمة من 42-44 ذرة كربون من
الكحولات الدهنية والحوامض الدهنية. ولأن الشكل الخارجي لشمع الهوهوبا هو كزيت
فلقد أصبح من المعتاد ومن الشائع تسميته زيت الهوهوبا بدلاً من شمع الهوهوبا
.
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أن زيت الهوهوبا مميز بأنه يدخل الجلد خلال ثوان بدون ترك أي أثر للزيت وحتى
الآن لم يستطع أحداً من تصنيعه من مواد كيماوية. لذلك فإن اكتشاف زيت الهوهوبا
في أواخر السبعينات من القرن الماضي كبديل لزيت حوت السبيرم الذي أصبح نادراً ثم
غير متوفراً بسبب القوانين الدولية في حظر صيده وقتله جعل الاعتماد على
زيت الهوهوبا في الصناعات التجميلية وتحسين زيوت السيارات والآلات أمراً لا مفر
منه.
إن الاستعمال الأولي لزيت الهوهوبا من قبل الهنود الحمر في أمريكا الشمالية حيث توجد شجيرات الهوهوبا البرية في مناطقهم الصحراوية ما زال ذلك أساساً لاستعمال هذا الزيت في أيامنا كعلاج للجلد وتقرحات وحروق الشمس ولتطرية البشرة ومنع التجاعيد. ولكن استعماله كزيت للقلي ومع الأطعمة الأخرى كما استعمله الهنود الحمر سابقاً ما زال غير شائعاً بسبب غلاء ثمن هذا الزيت وعدم معرفة أنه صالحاً للأكل مع أنه كزيت ثابت علمياً أنه صحي ويمكن أن يستخدم كزيت رجيم وملين للجهاز الهضمي. إن احتواء زيت الهوهوبا على كميات عالية نسبياً من التوكوفيرول لمجموعة فيتامين ي (E) التي تمنع الأكسدة والمعروفة بتنشيط الحيوية الجنسية والإخصاب ومنع الشيخوخة حسب العديد من الدراسات البيوكيميائية والصحية عن هذا الفيتامين زاد من رغبة المستهلك لاستخدام زيت الهوهوبا في مجالات مختلفة خاصة لمنع الأكسدة والشيخوخة وزيادة الحيوية الجنسية. كذلك فإن احتواء زيت الهوهوبا على حامض الميرستيك الذي يساعد في علاج الإلتهابات جعله فعالاً في الشفاء من آلام المفاصل وتشنجات العضل. |
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من
ضمن مزايا زيت الهوهوبا الأخرى بالإضافة للاستخدام الرئيسي في نضارة البشرة
والشعر هو انه بالإمكان الاستفادة من هذا الشمع السائل الصالح للأكل في الطعام
لأنه صحي ولا يزيد السمنة للجسم. ولأنه كما أسلفنا ليس دهناً أي ليس
ترايجلسرايد ولا يحتوي على الحوامض الدهنية الرئيسية الموجودة في الزيوت
النباتية والدهون الحيوانية هي مزايا مما يجعله عاملاً صحياً مسانداً في الغذاء.
فمن المعروف أن زيادة تناول الزيوت النباتية والدهون الحيوانية يسبب السمنة
وزيادة نسبة الكوليسترول في الدم ويضر بالصحة لمعظم الناس بشكل عام ولمرضى القلب
بشكل خاص. إن زيت الهوهوبا النقي لا يوجد به كوليسترول أوالحوامض الدهنية
التي تتكون منها دهون مترسبة بالجسم أو ذائبة في الدم.
إلا أن غلاء ثمن زيت الهوهوبا يجعل استعماله في الطعام محدوداً ولتبقي الاستعمالات لمعالجة الأمراض الجلدية وآلام المفاصل والحكة ونضارة البشرة والشعر هي السائدة في استخدامه. كذلك ولأن زيت الهوهوبا شمعاً سائلاً يمكن استعماله كما هو أو مضاف مع مادة جيلاتينية في تنظيف الأسنان وحماية اللثة من سيلان الدم ومنع الشعور بالبرودة على الأسنان الحساسة للهواء البارد. |
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