Effects of aqueous avocado pear (Persea americana) seed extract on alloxan induced diabetes rats

Abstract

ABSTRACT
Background: world is facing explosive increase in diabetes mellitus. It poses a serious challenge to primary health care in
developing countries, with negative consequences on the economy. This research is aim at evaluating the effect of Persea
americana aqueous seed extract on alloxan induced diabetes rats.
Methodology: Effects of the aqueous extract on groups of alloxan (150mg/Kg) induced diabetic rats was investigated. The blood
sugar and body weight of the rats was recorded at two weeks and four weeks interval, and one week after the withdrawal of the
extract. The test groups (III, IV, and V) were treated with 400mg, 800mg and 1200mg/kg body weight of the extract for 4 weeks.
Results: A significant decrease (P<0.001) in blood glucose were observed in all groups compared to Group II. A significant
increase in blood glucose (p<0.05) was observed one week after withdrawal of the extract. Significant increase in body weight
was recorded in groups III, IV and V compared to group II at P < 0.01, 0.001 and 0.05 respectively.
Conclusion: The findings may indicate anti-diabetic effects of the extract which may be due to certain mineral elements and
phytochemicals, and increase in weight in could be due to proper nutrient utilization probably induced by the avocado seeds’
extract. Avocado seeds may be of beneficial effects to diabetic patients.

Full text

Greener Journal of Medical Sciences ISSN: 2276-7797 Vol. 2 (1), pp. 005-011, January 2012.
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5
Research Article
Effects of aqueous avocado pear (Persea americana)
seed extract on alloxan induced diabetes rats
*A. J. Alhassan, M. S. Sule, M. K. Atiku, A. M. Wudil, H. Abubakar, S. A.
Mohammed
*Department of Biochemistry, Bayero University, Kano
Corresponding Author. Email: ajalhassan@yahoo.com Mobile phone: 08057623018
ABSTRACT
Background: world is facing explosive increase in diabetes mellitus. It poses a serious challenge to primary health care in
developing countries, with negative consequences on the economy. This research is aim at evaluating the effect of Persea
americana aqueous seed extract on alloxan induced diabetes rats.
Methodology: Effects of the aqueous extract on groups of alloxan (150mg/Kg) induced diabetic rats was investigated. The blood
sugar and body weight of the rats was recorded at two weeks and four weeks interval, and one week after the withdrawal of the
extract. The test groups (III, IV, and V) were treated with 400mg, 800mg and 1200mg/kg body weight of the extract for 4 weeks.
Results: A significant decrease (P<0.001) in blood glucose were observed in all groups compared to Group II. A significant
increase in blood glucose (p<0.05) was observed one week after withdrawal of the extract. Significant increase in body weight
was recorded in groups III, IV and V compared to group II at P < 0.01, 0.001 and 0.05 respectively.
Conclusion: The findings may indicate anti-diabetic effects of the extract which may be due to certain mineral elements and
phytochemicals, and increase in weight in could be due to proper nutrient utilization probably induced by the avocado seeds’
extract. Avocado seeds may be of beneficial effects to diabetic patients.
Key Words: Avocado pear (Persea americana) seed, Alloxan, Diabetes, Serum glucose.
INTRODUCTION
Medicinal plant have continued to attract attention in the global search for effective methods of using plants’ parts
(e.g. seeds, stems, leaves, roots and bark etc) for the treatment of many diseases affecting humans (Sofowora,
1993). Many important drugs used in medicine to day are directly or indirectly derived from plants due to its bioactive
constituents such as; alkaloids, steroids, tannins e.t.c (Cordeiro and Oniyangi, 1998). In recent years, secondary
plant metabolites previously with unknown pharmacological activities have been extensively investigated as sources
of medicinal agents (Krishnaraju et al., 2005).Thus it is anticipated that phytochemicals with adequate antimicrobial
efficacy will be use for treatment of bacterial infections (Balandrin et al., 1985).
Persea americana (luraceae) is one of the 150 varieties of avocado pear. The tree is widely cultivated in
tropical and subtropical areas (Lu et al., 2005). The seed of Persea americana (avocado seed) has diverse
application in ethno–medicine, ranging from treatment for diarrhea, dysentery, toothache, intestinal parasites, skin
treatment and beautification. The avocado seed oil has several health benefit e.g. for controlling human weight
(especially used for obese for weight loss) (Lopez et al., 1996; Roger, 1999). Persea americana leaves have been
reported to have or posses anti inflammatory and analgesic activities (Adeyemi et al., 2002). Antioxidant activity and
phenolic content of seeds of avocado pear was found to be greater than 70% (Soong and Barlow, 2004). The edible
part (fruit) is very popular in vegetarian cuisine, making a substitute for meat in sandwiches and salads, because of
its high fat content and high in valuable, health-promoting fats (Lu et al., 2005) . The fruit is not sweet but fatty,
almost distinctly, yet subtly flavored, and of smooth, almost creamy texture. Avocado fruits in many countries such as
Mexico, Brazil, South Africa and India are frequently used for milkshakes and occasionally added to ice-cream
(Zeldes, 2010).
Diabetes mellitus is often described as a group of complex metabolic disorders with a partial or absolute
insufficiency of insulin secretion and/or its action. These disorders are generally characterized by chronic
hyperglycemia and glucose intolerance (Naim et al., 2001). Diabetes mellitus is considered to be a bi-hormonal
disease involving insulin deficiency or defect in its utilization (e.g. receptor abnormality or presence of antibody to

Greener Journal of Medical Sciences ISSN: 2276-7797 Vol. 2 (1), pp. 005-011, January 2012.
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6
receptors) together with glucagon excess (Naim et al., 2001). Diabetes is one of the most common non–
communicable diseases in the world, affecting 5 to 10% of the adult population in the western world and hence,
representing a major cause of morbidity and mortality (Naim et al., 2001). There are two severe types of diabetes
mellitus, i.e. Type 1 or juvenile onset or insulin dependent diabetes mellitus (IDDM) and Type 2 or adult onset also
known as non–insulin dependent diabetes mellitus (NIDDM). In Type I diabetes; there is absence of insulin and
massive B-cells lesion and necrosis (Eisenberth, 2008). The Type 2 diabetes is characterized by a significant insulin
production ranging from less than normal to above normal but always in quantities insufficient to maintain glucose
homeostasis and organ resistance to insulin (Ripson, 2009). The characteristics symptoms of diabetes mellitus
includes excess thirst, polyphagia, polyurea, loss of body weight, frequent occurrence of boils, itching in the limbs,
and crowding around urine and impotence (WHO, 2003). This study is to evaluate effect of Persea Americana
aqueous seed extract on alloxan induced diabetes rats.
METHODOLOGY
Experimental Design
Twenty five (25) albino wistar rats weighing 180 – 220g were kept at Animal House of the Department of Biological
sciences, Bayero University, Kano Nigeria at 25 ± 2oC and 45-55 relative humidity. The animals were fed with
palletized commercial rat feed (Pfizer livestock co. Ltd, Aba, Nigeria) and tap water ad libitum. The rats were
assigned into five (5) groups of five (5) rats each as given below:
GROUP I
→
Normal untreated albino rats (NC)
GROUP II
→
Diabetic untreated albino rats (DC)
GROUP III
→
Diabetic treated albino rats (DGI), 400mg/Kg dose
GROUP IV
→
Diabetic treated albino rats (DGII), 800mg/Kg dose
GROUP V
→
Diabetic treated albino rats (DGIII), 1200mg/Kg dose
The baseline blood glucose level was determined, before groups II to V were induced with diabetes by intraperitoneal
(IP) injection of 150mg/kg body weight of alloxan monohydrate solution (Yanarday and Colac, 1998). The levels of
blood glucose of the animals were determined 48 hours after the injection using Glucometer (ACCU CHEK{Aviva})
model GMbH, 68298, those found to be diabetic (serum glucose
≥
200mg/l) were selected for the study. The weight
of the experimental animals was noted before the inducement, after the inducement and at interval of two weeks for
four weeks during extract administration.
Sample Collection and Preparation
Samples of ripe Avocado pears (Persea Americana) were purchased from Sabon Gari Market, Fagge local
government Kano State, Nigeria. The plant material was authenticated at Department of Biological Sciences, Bayero
University, Kano, Nigeria. The succulent part of the fruit was removed to obtain the seeds. The seeds were minced
by means of a grater and dried to constant weight in an oven at 55oC before being ground to powder and stored in
plastic container. Aqueous extract was prepared and adjusted to concentration of 0.4 g/cm3. Diabetes rats of groups;
DGI, DGII and DGIII) were orally treated daily with 400mg; 800mg and 1200mg/kg body weigh with the extract
respectively for four weeks, while DC and NC groups were garaged with normal tap water. Their blood glucose was
determined at interval of two weeks. The extract was then withdrawn and the blood glucose level was determined
one week after.
Statistical Analysis
The data was statistically analysed using GraphPad Instat3 Software (2000) version 3.05. by GraphPad Inc..
RESULTS AND DISCUSSION:
Table 1 show blood glucose mmol/l for groups of rats induced with diabetes and treated with aqueous seed extract of
avocado seed for zero, two four weeks and one week after withdrawal of the extract. The One-way Analysis of
Variance (ANOVA) for normal gave a P value of 0.9950 (P>0.05.) hence considered not significant; therefore
variation among column means is not significantly greater than expected by chance.

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Table 1: Blood glucose in mmol/l of alloxan induced diabetes rats orally treated with aqueous seed extract of Avocado
Americana for one 14 days, 28 days and 7days after withdrawal of the treatment.
Group Normal ZWKS TWKS FWKS OWAFWD
I , n
0mg/Kg alloxan
4.80
±
0.61
4.80
±
0.41
4.70
±
0.51
4.70
±
0.55
4.70
±
0.64
II, n
0mg/kg
4.7
±
0.50
26.50
±
4.04
27.90
±
4.34
28.90
±
4.25
28.90
±
4.05
III, n
400mg/Kg
4.70
±
0.50
25.80
±
7.16
12.70
±
5.01
10.50
±
3.47
14.87
±
1.62
IV, n
800mg/Kg
5.60
±
0.32
26.30
±
3.39
18.70
±
2.49
16.90
±
2.82
20.00
±
3.19
V, n
1200mg/Kg
5.20
±
0.70
24.40
±
0.68
8.50
±
1.15
6.60
±
1.00
13.70
±
3.01
Values are mean ± standard deviation, n=5
Key:
Normal= before induced with diabetes
ZWKS = 0 week after inducement with diabetes
TWKS = 2 weeks after inducement with diabetes
FWKS = 4 weeks after inducement with diabetes
OWAFWD = 1 weeks after withdrawal of treatment
ANOVA assumes that the data are sampled from populations (GI) with identical SDs. This assumption is tested using
the method of Bartlett (2000) given P value of 0.9345 (P>0.05), thereby suggesting that the differences among the
SDs are not significant. The statistical conclusion is expected since G I and normal columns were neither treated with
alloxan nor with aqueous extract of avocado seeds. Hence whatever variation recorded in any of the; groups or
columns could be as a result of the treatment.
ANOVA for ZWKS had a P < 0.0001, variation among column means (GI vs GII, III, IV and V) is considered
extremely significant and this may confirm inducement of diabetic among alloxan treated groups. Table 2: Show
Tukey-Kramer multiple comparisons test for Group II and variation among raw means (Normal vs Zwks, Twks, Fwks
and OWAFWD) is considered significant (P<0.001), while variation in raw mean among alloxan induced diabetic rats
with time is not significantly different (P>0.05). This may confirm inducement of diabetic condition in the alloxan
treated groups and it lasted throughout the study period. This out come should be expected since the group was not
treated with extract and show no evidence of natural healing (Table1and 2).
Table 2: Tukey-Kramer Multiple Comparisons Test, for different period in Group II
Mean
Comparison difference q p value
=================================================================
Norm vs Zwks -21.800 13.040 *** P<0.001
Norm vs Twks -23.200 13.877 *** P<0.001
Norm vs Fwks -24.200 14.475 *** P<0.001
Norm vs OWAFWD -24.200 14.475 *** P<0.001
Zwks vs Twks -1.400 0.8374 ns P>0.05
Zwks vs Fwks -2.400 1.436 ns P>0.05
Zwks vs OWAFWD -2.400 1.436 ns P>0.05
Twks vs Fwks -1.000 0.5982 ns P>0.05
Twks vs OWAFWD -1.000 0.5982 ns P>0.05
Fwks vs OWAFWD 0.000 0.000 ns P>0.05
If the value of q is greater than 4.232 then the P value is less than 0.05 and is specified by the script ٭٭٭

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ANOVA for TWKS, is considered extremely significant (P < 0.0001) therefore, variation among column means is
significantly greater than expected by chance. This could be due to treatment given to group III, IV and V. Table 3
show the outcomes on comparing variation in blood sugar in group III with duration of treatment. The non significant
difference for Norm vs Twks, and Norm vs Fwks is indicating probable glucose lowering effect of avocado aqueous
seed extract on alloxan induced diabetes rats. While, the significant different (p<0.01) in Norm vs OWAFWD is
indicating that the avocado extract may have management effects but not curative. The significant difference (p<
0.001) for Zwks vs Twks, and Zwks vs Fwks had confirmed the glucose lowering effect of the extract when compared
with that of the diabetes rats before treatment. The significant difference at p <0.01 for Zwks vs OWAFWD is
indicating that the blood glucose level rising one week after the withdrawal of the treatment, therefore, confirmed
management effect of the extract.
Table 3: Tukey-Kramer Multiple Comparisons Test, for different period in Group III
Mean
Comparison Difference q P value
================================================================
Norm vs Zwks -21.100 1.042 *** P<0.001
Norm vs Twks -8.000 4.187 ns P>0.05
Norm vs Fwks -5.800 3.035 ns P>0.05
Norm vs OWAFWD -10.170 5.322 ** P<0.01
Zwks vs Twks 13.100 6.856 *** P<0.001
Zwks vs Fwks 15.300 8.007 *** P<0.001
Zwks vs OWAFWD 10.930 5.720 ** P<0.01
Twks vs Fwks 2.200 1.151 ns P>0.05
Twks vs OWAFWD -2.170 1.136 ns P>0.05
Fwks vs OWAFWD -4.370 2.287 ns P>0.05
If the value of q is greater than 4.232 then the P values is less than 0.05 and are specify by the script (٭) base on p
value.
ANOVA for FWKS shows extremely significant variation (P < 0.0001) among column means greater than
expected by chance, it could be due to treatment given to group III, IV and V. Table 4 gives the assumption test for
GIV, ANOVA ‘assumes that the data are sampled from populations with identical SDs’. This assumption is tested
using the method of Bartlett (2000). Bartlett statistic (corrected) = 12.650, the P value is 0.0131, Bartlett's test
suggests that the differences among the SDs is significant. From Tables 1 and 4, the significant (p<0.001) variation in
Norm vs Twks, and Norm vs Fwks despite treatment with higher dose compared to Group III (Table 4, is unexpected
this could be due to the time difference between feeding and glucose determination. However, the significant
difference at p<0.01, 0.001 and 0.05 respectively for Zwks vs Twks, Zwks vs Fwks and Zwks vs OWAFWD also
indicated the hypoglycemic effects of the extract on alloxan induced diabetes rats.
Table 4: Tukey-Kramer Multiple Comparisons Test, for different period in Group IV
Mean
Comparison Difference q P value
=================================================================
Norm vs Zwks -20.700 17.268 *** P<0.001
Norm vs Twks -13.100 10.928 *** P<0.001
Norm vs Fwks -11.300 9.427 *** P<0.001
Norm vs OWAFWD -14.400 12.013 *** P<0.001
Zwks vs Twks 7.600 6.340 ** P<0.01
Zwks vs Fwks 9.400 7.842 *** P<0.001
Zwks vs OWAFWD 6.300 5.256 * P<0.05
Twks vs Fwks 1.800 1.502 ns P>0.05
Twks vs OWAFWD -1.300 1.084 ns P>0.05
Fwks vs OWAFWD -3.100 2.586 ns P>0.05
If the value of q is greater than 4.232 then the P values is less than 0.05 and are specify by the script (٭) base on p
value.

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One-way Analysis of Variance (ANOVA) for OWAFWD shows that variation among column means is significantly
greater than expected by chance (P < 0.0001). Table 5 shows the out comes for ANOVA that ‘assumes that the data
are sampled from populations with identical SDs’. This assumption is tested using the method of Bartlett. Bartlett
statistic (corrected) = 12.786, the P value is 0.0124. Bartlett's test suggests that the differences among the SDs are
significant. None significant (p>0.05) difference in Norm vs Fwks may suggest that the hypoglycemic effect of the
avocado seed extract is based on dose and duration of exposure.
Table 5: Tukey-Kramer Multiple Comparisons Test, for different period in Group V
Mean
Comparison Difference q P value
==================================================================
Norm vs Zwks -9.200 13.097 *** P<0.001
Norm vs Twks -3.300 4.698 * P<0.05
Norm vs Fwks -1.400 1.993 ns P>0.05
Norm vs OWAFWD -8.500 12.101 *** P<0.001
Zwks vs Twks 5.900 8.399 *** P<0.001
Zwks vs Fwks 7.800 11.104 *** P<0.001
Zwks vs OWAFWD 0.7000 0.9965 ns P>0.05
Twks vs Fwks 1.900 2.705 ns P>0.05
Twks vs OWAFWD -5.200 7.403 *** P<0.001
Fwks vs OWAFWD -7.100 10.108 *** P<0.001
If the value of q is greater than 4.232 then the P value is less than 0.05 and is specify by the script (٭) base on p
value.
Table 6: weight (g) of alloxan induced diabetes rat orally treated with aqueous extract of avocado seeds
for 2 and 4 weeks, and 1 week after withdrawal of treatment
Group
Normal
ZWKS
TWKS
FWKS
OWAFWD
I
0mg/Kg alloxan
180
.0
±
1.13
180
.0
±
1.20
183.3
±
4.08
206.7
±
8.17
220
.0
±
14.14
II
0mg/kg
180
.0
±
1.300
176.7
±
4.08
170.
0
±
7.07
163.3
±
3.7.3
156.7
±
3.73
III
400mg/Kg
193.3
±
7.45
186.7
±
17
216.7
±
10.80.
22
0.
0
±
14.14
213.3
±
16.33
IV
800mg/Kg
200
.0
±
0.00
186.7
±
17
206
.7
±
8.17
220
.0
±
14.14
220
.0
±
14.14
V
1200mg/kg
200
.0
±
0.00
193.3
±
8. 17
200
.0
±
0.00
201.3
±
8.17
206.7
±
17
Values are mean standard deviation, n=5

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Table 7: Tukey-Kramer Multiple Comparisons Test for weight (g) of normal, diabetes; treated and untreated,
and one week after withdrawal of the treatment diabetes rats
Mean
Comparison Difference q P value
=============================================================
GI vs GII 24.660 4.137 ns P>0.05
GI vs GIII -11.980 2.010 ns P>0.05
GI vs GIV -16.680 2.799 ns P>0.05
GI vs GV -6.266 1.051 ns P>0.05
GII vs GIII -36.640 6.147 ** P<0.01
GII vs GIV -41.340 6.936 *** P<0.001
GII vs GV -30.926 5.189 * P<0.05
GIII vs GIV -4.700 0.7886 ns P>0.05
GIII vs GV 5.714 0.9587 ns P>0.05
GIV vs GV 10.414 1.747 ns P>0.05
If the value of q is greater than 4.232 then the P value is less than 0.05 and is specify by the script (٭) base on p
value
Hypoglycemic effect of the avocado seed extract may be due probable contents of elements such as calcium,
magnesium, potassium, sodium, zinc, chromium e.t.c that play key role in blood glucose homeostasis by regulating
the key enzymes involved in gluconeogenesis in the liver e.g. glucose-6- phosphatase, fruitcose-1, 6-
bisphosphatatase and phosphoenolpyruvate carboxykinase, thereby blocking gluconeogenesis and enhancing
glucose utilization in the body (Broadhust, 1997). The seed may in addition to these elements contains certain
hypoglycemic agents such as phytochemicals (e.g. flavonoids, saponins, steroids, terpenoids, tannins and alkaloids
etc) which contain insulin stimulatory substances such as insulin receptors substrate (IRS), prohornone convertase,
glycogen synthase, the b3 adrenergic receptor, glucose dependent insulinotrophic polypeptide (GIP) receptor and
peroxisome proliferators – activated receptor gamma e.t.c. (Broadhust, 1997). However, the mechanism by which the
extract lowered the blood glucose level in alloxan induced diabetic rats is still unclear. It could be by stimulating
peripheral utilization of glucose by inhibiting absorption in the gastrointestinal tract (GIT), increasing glucose
metabolism, or regenerating the pancreatic tissue or potentiating the insulin secretion by the surviving B- cells. A
prolonged administration of the extract shows higher hypoglycemic effects on alloxan induced diabetic rats than are
shorter period. And after withdrawal of the treatment for one week the blood glucose gradually rised, however below
that of the untreated group, this signifies the management effect of the avocado seed extract.
The increase in weight of diabetic rats treated with avocado seed extract (Table 6) was found to be
significant between diabetes groups treated with avocado seed and diabetic non treated (Group II). This could be
due to certain compounds and or mineral elements that may stimulate effective utilization of nutrients. In addition, the
seed may contain nutrients such as protein and fat this coupled with their effective utilization, may be responsible for
the weight gain.
CONCLUSION
The findings of this study indicate that consumption of the aqueous extract of avocado pear seed (Persea americana)
exerts significant hypoglycemic effects on alloxan induced diabetic rats. The findings may support acclaimed
traditional use of avocado pear seed for controlling hyperglycemia in diabetes. The findings also indicate that
prolonged oral administration of aqueous extracts of avocado pear seed has a greater effect in management of
diabetes mellitus than short term administration.
REFERENCES:
Adeyemi, O.O., Okpo, S.O. and Ogunti O.O. (2002): Analgesic and anti-inflammatory effect of the aqueous extract of
leaves of Persea americana Mill (Lauraceae). Fitoterapia 73: 375–380.
Balandrin, M.F., Kjocke A.J and Wurtele, D.F (1985): Natural Plant chemicals sources of Industrial and
Pharmaceutics, Humana press, New Jersey USA; Pp. 137-141.

Greener Journal of Medical Sciences ISSN: 2276-7797 Vol. 2 (1), pp. 005-011, January 2012.
www.gjournals.org
11
Broadhurst, C.L. (1997). Nutrition and non – insulin diabetes mellitus form by the combined administration of
streptozotocin or alloxan and poly (adenosine diphosphate ribose). Engg. 2: 125
Codeiro N. J. V. and Oniyangi, O. (1998). Phytomedicines. 2nd Edition. Pp. 200-2005.
Eisenbarth, S., Polonsky, S. and Buse, B. (2008). Type 1 Diabetes Mellitus. In: Williams Textbook of Endocrinology.
11th ed. Philadelphia, Pa: Saunders Elsevier; p. 31.
Krishnaraju, A.V., Rao T.V. and Sundararaju. A. (2005): Assessment of bioactivity of Indian medicinal plants using
Brine shrimp (Altenaria salania) lethality assay. Int. J. Appl. Sci. Int. J. Appl. Sci Engg. 2: 125-134.
Lopez, R., Frati, C., Hernandez, C., Cervantes, S., Hernandez, H., Juarez, C. and Moran, S. (1996).
"Monounsaturated fatty acid (avocado) rich diet for mild hypercholesterolemia". Arch-Med-Res,. 27 (100) :678-
701.s
Lu Q.Y., Arteaga, J. R, Zhang, Q., Huerta, S., Go, V.L and Heber, D. (2005): Inhibition of prostate cancer cell growth
by an avocado extract: role of lipid-soluble bioactive substances. J. Nutr. Biochem. 16: 23-30.
Naim, S. Raanan, S. Moshe, B. Amos, E. (2001). "Insulin in human milk and the prevention of type 1 diabetes".
Pediatric Diabetes 2 (4): 175–7.
Rees, D. A. and Alcolado, J.C. (2005). Animal models of diabetes mellitus. Diabetic Medicine. 22:359-370.
Ripsin, M., Kang, H. and Urban, R. (2009). "Management of blood glucose in type 2 diabetes mellitus.” American
family physician 79 (1): 29-36.
Roger, C. R. (1999) The nutritional incidence of flavonoids: some physiologic and metabolic considerations.
Experientia 44 (9):725-804.
Sofowora, A. (1993). Medicinal Plants and Traditional in Africa 2nd ed. Spectrum Book Limited, Ibadan. Pp. 6 – 188.
Song, Y. and Barlow, P. J. (2004): Antioxidant activity and phenolic content of selected fruit seeds. Food Chem.,
88(3):411–417
WHO/FAO. Diet, nutrition, and the prevention of chronic diseases. Geneva: World Health Organization, 2003.
Yanarday R. and Colac H. (1998). Effect chard (Beta vulgaris L. varcicla ) on blood glucose level in normal and
alloxaninduced diabetic rabbit. J. Ethnopham. 4:309-311.
Zeldes, L. A. (2010). "Eat this! The ‘Hass’ avocado, black and green and creamy". Dining Chicago. Chicago's
Restaurant & Entertainment Guide, Inc.