Current Research of Journal Biological Science 4(1): 4-9, 2012
© Maxwell Scientific Organization, 2012
Submitted: June 21, 2011 Accepted: November 10, 2011 Published: February 20, 2012
Corresponding Author: A.O. Adesuyi, Department of Chemical and Enviromental Sciences, School of Science and Technology,
Babcock University, Ilishan-Remo, Nigeria
Nutritional and Phytochemical Screening of Aloe barbadensis
A.O. Adesuyi, O.A. Awosanya, F.B. Adaramola and A.I. Omeonu
Department of Chemical and Environmental Sciences, School of Science and Technology,
Babcock University, Ilishan-Remo, Nigeria
Abstract: The aim of this research study is to analyse qualitatively and quantitatively the Aloe barbadensis for
Proximate, Anti-Nutrient and Phytochemical composition. The Proximate, Anti-Nutrient composition and
Phytochemical screening of Aloe barbadensis were determined. The Proximate composition involves the
Moisture content, Crude protein, Crude fibre, Crude Fat, Ash content and Carbohydrate. The Anti-Nutrients
involved Oxalate, Tannins and Phytate while the Phytochemicals determined were the Saponins, Phenols,
Alkaloids and Flavonoids. Aloe barbadensis was found to be rich in Carbohydrate (73.07%), so it can be used
as a good source of Carborhydrate. The Protein and Fat content were found to be relatively low, (4.73 and
0.27%) respectively. But Aloe barbadensis can still be used as a source of Protein and Fat. Qualitatively,
Tannin, Oxalate and Phytate were found in trace amount. Tannin, Phytate and Oxalate contents were 0.155
g/100 g, 0.683 g/100 g, and 0.524 g/100 g, respectively. This could affect the availability of Minerals in Aloe
barbadensis. It was also discovered that Phytochemicals are present in quantities of 0.232 g/100 g, 5.651
g/100 g, 2.471 g/100 g and 3.246 g/100 g for Phenols, Saponins, Alkaloids and Flavonoids, respectively. This
is an indication of Cosmetic and medicinal Value of Aloe barbadensis. The Sample was also found to be a rich
source of minerals. Sodium and Potassium content (5280 and 10670 PPM), respectively indicates the tendency
of Aloe barbadensis to be able to regulate or control the osmotic balance of the body fluid as well as body pH.
Aloe barbadensis is also found to be rich in Phosphorus (6657 PPM), which is essential for bone formation.
Lead occur in traces. Magnesium (325.8 PPM) is also present, which could help to lower the blood pressure.
The overall data suggest that Aloe barbadensis has some Nutritional and Medicinal Properties.
Key words: Aloe barbadensis antinutrients, mineral medicinal, nutritional, phytochemicals, proximate
Plants have been of importance to medicine for
thousands of years. Even today the World Health
Organization (WHO) estimates that up to 80% of people
still rely on traditional remedies such as herbs for their
medicine (Arunkumar and Muthuselvam, 2009).One of
such herbs is Aloe barbadensis which has caught the
global commercial interest in the world of Science,
particularly medical science for their proposed health
benefits despite little or no scientific evidence justifying
the anecdotal claims accompanying many of its products
(Botes et al., 2008). Aloe barbadensis, also known asAloe
verais part of the Liliaceaeor asphodelaceae plant family.
It is cactus like plant with green dagger-shaped leaves that
are fleshy, tapering, spiny, marginated and filled with a
clear viscous gel. It has thick leaves that grow in a rosette
shape. Many species of Aloe appear to be stem-less, with
the rosette growing directly at ground level; other
varieties may have a branched or unbranched stem from
which the fleshy leaves spring. They vary in color from
grey to bright-green and are sometimes striped or mottled.
Some Aloe natives to South Africa are arborescent. The
parenchyma cells of the leaves contain large quantities of
pulp. It is a monocotyledon and a member of the lily
family. It is an evergreen plant. Aloe barbadensis can
grow up to three feet tall, although most specimens are
between one and two feet tall. It is native to East and
South Africa and is grown in most subtropical and
tropical locations, including Latin America and the
Caribbean. The plant has many common names and is
often referred to as burn plant, first-aid plant, or medicine
plant. Its name is most likely derived from the Arabic
word “Alloeh”, meaning “shining bitter substance”. It is
cultivated almost everywhere in the world, both as a
houseplant and for its medicinal qualities. It grows best in
full sunshine and does not require much water. It does not
grow well at temperatures below 32ºF (0ºC).
Aloe species primarily inhabit relatively dry, warm
climates, but has been introduced successfully in the
southern United States and Australia as well. These
climates tend to have warm, dry summers and cool, moist
winters, with more precipitation occurring during the
winter. Fires occur frequently in summers, and the species
Curr. Res. J. Biol. Sci., 4(1): 4-9, 2012
that survive are those that tolerate fire and drought well.
Nutrient density is low in these regions, and thus the
habitat cannot support large predators. Smaller animals
and especially plants predominate. These habitats have a
wide variety of species that have adapted to these unique
ecological conditions, such species of Aloe, are endemic.
Aloe albida, for example, is found in the wild only in
South Africa. Aloe is a perennial and takes 4-5 years to
mature. Plants can live and reproduce for up to 25 years.
Its tubular flowers, yellow to red in color, grow in arrow-
shaped clusters on spikes that are up to 3 feet tall. It
flowers in springtime. Its fruits are small and not
particularly significant. In addition to propagating via
seeds, it can reproduce by offsets, which may take root
pto 6 feet away from the plant and grow into new plants
There are over 500 species ofAloe, including Aloe perryi
from Socotra Island or Zanzibar and Aloe ferox from
Aloe veraleafcontains more than 200 different
constituents. Some constituents are:
Acemannan: This is a D-isomer mucopolysaccharide that
is extracted from aloe vera leaves with mannoacetate as
the monomer linked by $-1,4- glycosidic linkages
Glycosidic bond (3,6). This polymer is hydrophilic: 50
hydrogen bond acceptors, 19 hydrogen bond donors and
log P of -3.27. Therefore, its permeability (and hence
bioavailability) has been scored to be 1 according to
Lipinsky’s rule of five. Acemannan as an
immunostimulant has been demonstrated to induce
macrophages to secrete interferon (INF), tumor necrosis
factor- (TNF-") and interleukins (IL-1) - which might
help in preventing or abrogating viral infection. These
three cytokines are known to cause inflammation and
interferon is released in response to viral infections and
other polysaccharides boost T-lymphocyte cells which
help promote skin healingand neutralize many of the
enzymes responsible for damaging the mucosal wall
Aloe-emodin: of IUPAC nomenclature of 1,8-dihydroxy-
3-(hydroxymethyl)-9,10-anthracenedione and chemical
formula, C15H10O5, is an anthraquinone present in aloe
latex, an exudate from the aloe plant which has a strong
Aloins: also known as “Barbaloin” is a bitter, yellow-
brown colored compound noted in the exudates of at least
68 Aloe species at levels from 0.1 to 6.6% of leaf dry
weight making between 3 and 35% of the total exudates,
and in another 17 species at indeterminate levels
(Reynolds, 1995). It is used as a stimulant-laxative,
treating constipation by inducing bowel movements. The
compound is present in what is commonly referred to as
the aloe latex that exudes from cells adjacent to the
vascular bundles, found under the rind of the leaf and in
between it and the gel. When dried, it has been used as a
bittering agent in alcoholic beverages.
Enzymes: They act as biochemical catalysts that break
down the proteins we eat into amino acids. The enzymes
turn the food we eat into fuel for every cell in our body,
enabling the cells to function and work efficiently. “The
main enzymes found in Aloe vera include Amylase
(breaks down sugars and starches), Bradykinase
(stimulates immune system, analgesic, anti-
inflammatory), Catalase (prevents accumulation of water
in the body), Cellulase (aids digestion-cellulose), Lipase
(aids digestion-fats), Oxidase, Alkaline Phosphatase,
Proteolytiase (hydrolyses proteins into their constituent
elements), Creatine Phosphokinase (aids metabolism), and
Galactomannans: (Long chain sugars derived from
plants), are polysaccharides consisting of a mannose
backbone with galactose side groups (more specifically,
a (1-4)-linked "-D-mannopyranose backbone with branch
points from their 6-positions linked to "-D-galactose, i.e.
Minerals: Some minerals like Sodium, potassium,
calcium, magnesium, manganese, copper, zinc, chromium
and iron are also Constituents of Aloe barbadensis
Vitamins: Vitamins like B1, B2, B6, C, $-carotene,
choline, folic acid, "-tocopherol are also Aloe
Mucopolysaccharides [MPS] (Long-chain sugars):
Mucopolysaccharides [MPS] or glycosaminoglycans
(GAGs) are long unbranched polysaccharides consisting
of a repeating disaccharide unit. The repeating unit
consists of a hexose (six-carbon sugar) or a hexuronic
acid, linked to a hexosamine (six-carbon sugar containing
nitrogen). They are found in every single cell in the body.
The human body stops manufacturing its own
mucopolysaccharides around puberty and from then on
must rely on outside sources.Some examples of
glycosaminoglycan uses in nature include heparin as an
anticoagulant, hyaluronan as a component in the synovial
fluid lubricant in body joints, and chondroitins, which can
be found in connective tissues, cartilage, and tendons.
Curr. Res. J. Biol. Sci., 4(1): 4-9, 2012
Mucopolysaccharides work in the body in the following
CAs an anti-coagulant, heparin
CBy facilitating absorption of water, electrolytes and
nutrition in the gastrointestinal tract and maintaining
CBy lining the colon to keep out toxic waste from the
CBy lubricating the joints, hyaluronan which act as a
component in the synovial fluid lubricant in body
joints, and chondroitins, which can be found in
connective tissues, cartilage, and tendons
CBy protecting teach cell from microbial invasion
CAnthraquinone glycosides (these molecules are split
by the normal bacteria in the large intestines to form
other molecules called aglycones), the main one
Usage of aloe vera: The bitter yellow juice found
between the gel and the outer skin of the leaf is dried and
used as a laxative.
Medicinal part used: The leaves, the fresh leaf gel and
CAloe latexis the sticky residue left over after the
liquid from cutAloe leaveshas evaporated.
CAloe vera extractis made by pulverizing the
wholeleavesof the plant.
CAloe juiceandgelis made from the inner leaf (most
commonly used for minor cuts and burns).
Proximate analysis: Proximate analysis, also known as
Weende analysis is a chemical method of assessing and
expressing the nutritional value of a feed, which reports
the moisture, ash (minerals), crude fibre, crude fat and
crude protein (total nitrogen) present in a fuel as a
percentage of dry fuel weight. Carbohydrate (nitrogen-
free extract) is determined by difference. The proximate
analyses gives the overall nutritional composition of the
sample in question, this is briefly complemented by
Antinutrient and Mineral composition of the sample.
Phytochemicals: Phytochemicals (from the Greek word
“phyto”, meaning plant) are biologically active
compounds, found in plants in small amounts, which are
not established nutrients but which nevertheless seem to
contribute significantly to protection against degenerative
disease (Dreosti, 2000). The term does not apply to
compounds used in relation to treating an established
acute disease, but rather to substances that are protective
at low levels against the development of degenerative
diseases over a lifetime (Dreosti, 1998). They are natural
bioactive compounds found in plant foods that interplay
with nutrients and dietary fibre to protect against diseases.
It is also well known that plants produce these chemicals
to protect themselves, but recently research demonstrates
that they can protect humans against diseases as well as
assisting in risk reduction for a variety of chronic and
Objectives of the study:
CTo investigate qualitatively the Nutritional content of
CTo investigate quantitatively the Nutritional content
of Aloe barbadensis.
CTo investigate quantitatively the photochemical
content of Aloe barbadensis.
MATERIALS AND METHODS
Aloe barbadensis leaves, nutritional and phytochemical
analyses: This research study was carried out in April,
2011 at the Department of Chemical and Enviromental
Sciences. School of science and technology, Babcock
University, Ilishan-Remo, Nigeria.
Aloe barbadensis plant were obtained from a local
garden in Lagos, Shomolu District, who grows them for
individual use and as an ornamental plant. The plant leaf
was identified by Mr. Odewo, a herbarium caretaker at
university of Lagos, Akoka. The leaves were plucked off
the stem, rinsed, cut at the lateral section to have a larger
surface area and placed on clean polythene Bag. The plant
materials were air dried under the sun for one week and
were later pulverized into fine powder using a kitchen
blender and stored in a clean Polythene bag and was kept
in a cool place prior to Laboratory Analyses.
Nutritional property analyses:
Proximate analysis of aloe barbadensis powder:
Proximate analysis is a system of analysis of nutrients
also termed “conventional analysis”, in which the gross
components rather than the individual nutrients amino
acids, fatty acids, monosaccharides e.t.c. are determined
(Onyeike and Osuji, 2003). The following are constituent
parameter: moisture, ash, crude protein, fat, crude fibre
All of these were carried out using the Method of
analyses described by Onyeike and Osuji (2003).
Mineral analyses: The atomic Absorption
spectrophotometer (AAS) was used for the analyses of the
following metals: Mg, Zn, Fe, Mn, Cu, Pb and P while the
Flame Photometer was used in the analyses of K & Na.
Curr. Res. J. Biol. Sci., 4(1): 4-9, 2012
Using AAS, a known amount of the sample was placed in
a dish and heated with burnsen burner in a fume cupboard
until there was no smoke emitted. This was transferred to
the dessicator in other for it to cool after which 0.1m HCl
solution was added to the ash. The resulting solution was
filtered and diluted. Suitable salts of the metals in
questions were used to make their standards, lamps were
fixed and the analyses was done. Using the flame
photometer, the Diluents of sample was aspirated into
the jenway Digital flame photometer using the filter
corresponding to each mineral element. All of these were
carried out using the method of analyses described by
Phytochemical analyses: Phytochemical analyses
includes the Phenol determination, determination of
Saponin, determination of Alkaloids and Flavonoids
determination. All of these were determined based on
methods of analyses described by AOAC (1990).
The Proximate composition of the Sample is shown
in Table 1. The values represent the Mean triplicates +
The qualitative Anti-Nutrient Screening of Aloe
barbadensis is shown in Table 2.
The quantitative Anti-Nutrient Screening of Aloe
barbadensis is shown in Table 3. Values are Mean
Triplicate + Standard Error.
The quantitative Phytochemical Screening is shown
in Table 4. Values are Mean Triplicate + Standard Error.
Table 5 shows the Mineral Composition of Aloe
Table 1 shows the proximate analysis of Aloe
barbadensis. The average carbohydrate content (73.08%),
which is the highest parameter will be a good source of
Carbohydrate. Carbohydrates provide readily accessible
fuel for physical performance and regulate nerve tissue
(Whitney and Rolfes, 2005).
Average moisture content (11.71%) was the second
highest Parameter noted. To much of moisture in any
sample has been proved to cause caking especially in
flour and can also determine the Storage/Shelve life and
the viability of microorganisms’ growth (Adeyeye and
Ayejuyo, 2000). Average crude fibre (7.84%) was the
third highest parameter noted, this implies that they can
serve as a source of dietary fibre (Agostoni et al ., 2001)
and can be employed in the treatment of diabetes, obesity
and gastrointestinal tract diseases. Its also an indication
Table 1: Proximate composition of Aloe barbadensis
Moisture Content 11.71+0.02
Crude Protein 4.73+0.01
Crude Fibre 7.84+0.01
Crude Fat 0.27+0.01
Table 2: Qualitative anti-nutrient screening
(+): Trace Amount Present; (+)(+): Abundant Amount Present; (-): No
Table 3: Quantitative anti-nutrient screening
Table 4: Quantitative phytochemical screening
Table 5: Mineral composition
Elements (PPM) (%)
Mg 325.7 0.033
Zn 71.5 0.007
Fe 28.8 0.003
Mn 128 0.013
Cu 15.3 0.002
Pb 1.7 0.00017
P 6650.1 0.665
Na 5170 0.517
K 10615 1.062
that it contains a proportion of Cellulose, Hemicellulose
and Lignin (Saldanha, 2003).
The lowest parameter noted was average crude fat
content (0.27%), which are universally stored forms of
energy in living organisms. They are major structural
elements of biological membranes as phospholipids and
sterols (Nelson and Cox, 2008).
Average ash content (2.36%) is a reflection of the
mineral contents preserved in the leaves. Minerals are
essential for the proper functioning of tissues and act as
second messengers in some sbiochemical cascade
mechanisms (Antia et al., 2006).
Average crude protein (4.73%), would serve as
enzymatic catalyst, mediate cell responses, control growth
and cell differentiation (Whitney and Rolfes, 2005).
Table 2 and 3 show qualitative and quantitative anti-
nutrients of A. barbadensis. Tannins (0.155 g/100 g),
which were found in the plant, are known to be effective
in the treatment of sore throat, diarrhoea and
Curr. Res. J. Biol. Sci., 4(1): 4-9, 2012
Tannins are known for their abilities to precipitate
with iron and other metals, thereby reducing their
Oxalates (0.448 g/100 g) affects calcium and
magnesium metabolism and react with proteins to form
complexes which have an inhibitory effect in peptic
digestion (Akande et al., 2010).
Phytic acid (0.683 g/100 g) (inositol hexaphosphate)
in plants binds calcium in the intestinal lumen, preventing
its absorption as well other minerals, including zinc, are
also chelated by phytate.
Table 4 shows phytochemical screening of Aloe
barbadensis indicating the amount of saponins, alkaloids,
phenols and flavonoids. These compounds are known to
be biologically active and therefore aid the antimicrobial
activities of Aloe barbadensis (Igbinosa et al., 2009).
Alkaloids (2.471 g/100 g), a secondary metabolite
compound observed in the extract of Aloe barbadensis
has the biological property of toxicity against cells of
foreign organisms. It activities have been widely studied
for their potential use in the elimination and reduction of
human cancer cell lines (Nobori et al., 1994). Alkaloids
which are one of the largest groups of phytochemicals in
plants have amazing effects on humans and this has led to
the development of powerful pain killer medications
(Kam and Liew, 2002).
Saponin (5.651 g/100 g) found to be present in Aloe
barbadensis extracts and has supported the usefulness of
this plant in managing inflammation. Just et al. (1998)
revealed the inhibitory effect of saponins on inflamed
Flavonoids (3.246 g/100 g), another constituent of
Aloe barbadensis extracts are large compounds occurring
ubiquitously in food plants. They at times occur as
glycosides and contain several Phenolic hydroxyl groups
on their ring structure. Some flavonoids are antioxidants
and has been proved to exhibit a wide range of biological
activities like antimicrobial, anti-inflammatory, anti-
angionic, analgesic, anti-allergic, cytostatic and
antioxidant properties (Hodek et al., 2002).
Phenols (0.232 g/100 g) also found present in plant
sources are major group of compounds acting as primary
antioxidants or free radical scavenger.
Table 5 shows a great deal of mineral composition of
Aloe barbadensis. It’s a proved fact that Potassium is the
most abundant mineral in Nigerian agricultural products
(Oshodi et al., 1999).This is shown in the table. The next
mineral to Potassium in terms of value is Phosphorus,
which is vital in bone formation (Adetuyi and
Akpambang, 2005), followed by sodium. Aloe
barbadensis can be used as a source Sodium and
Potassium. Since High amount of Potassium and
Magnesium may help to lower blood pressure
(Otsuki et al., 2010), Aloe barbadensis can be used as a
source of these minerals. Iron is vital in the formation of
haemoglobin and normal functioning of central nervous
system (Otsuki et al., 2010), this sample contain
considerable amount of iron and can therefore be used as
a source. The presence of lead could be due to
bioaccumulation. Micro minerals like copper,
Manganense and Zinc are present too
The analyses carried out on Aloe barbadensis
indicates its Nutritional and Phytochemical composition.
The Proximate analysis shows a high level of
Carbohydrate and crude fibre with a little bit of Protein.
The mineral analysis indicates that Aloe barbadensis
contain macro/major elements which are needed in high
quantity in meals, Potassium been the highest. Sodium
and Magnesium were also found to be abundant in this
sample. Micro elements were also found to be present.
These are all good indication of high nutritive value.
Despite the presence of some Anti-nutrient that could
serve as mineral inhibitors, Aloe barbadensis can still be
used as sources of these minerals. The Phytochemical
content also is an indication that this sample has potential
protective vices against degenerative diseases.
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