Pharmacological Screening of Bambusa vulgaris and Cocos nucifera Root Extracts for Their Potential Diuretic Activity.

 

Potdar V.H.¹*, Pachupate V.J.², Khavare N.B.¹, Khot P.V.¹, Koulavkar V.S.¹ and Koulave S.B.¹

¹Department of Pharmacology, Tatyasaheb Kore College of Pharmacy, Warananagar-416113, Maharashtra, India.           ²Department of Biotechnology, Tatyasaheb Kore Institute of Engineering and Technology, Warananagar-416113, (M.S.)

*Corresponding Author E-mail: vhp_pharmacology@rediffmail.com

ABSTRACT:

Cocos nucifera (Palmae) and Bambusa vulgaris (Gramineae) are used in Indian traditional medicine system as diuretics. However so far no scientific study revealed their diuretic potential. Therefore present study was undertaken to evaluate diuretic potential of aqueous extract of roots of Cocos nucifera and Bambusa vulgaris in albino rats. Preliminary phytochemical screening of aqueous extracts of both plants was carried out to determine the nature of phytoconstituents present in it. Acute toxicity of the both extracts was determined using wistar rats. The method described by Lipschtiz et al and Kavimani et al, was employed for the evaluation of diuretic activity. Different parameters viz. total urine volume, urine pH, urine concentration of electrolytes such as Na⁺, K⁺ and Cl^- , Na⁺/K⁺ ratio and diuretic index have been evaluated. Each extract was evaluated at 3 different doses as 100, 200 and 300 mg/kg B.W. of rat. Aqueous extract of C.nucifera roots exhibited dose dependent increase in the total urine volume and excretion of electrolytes. On the other hand, no significant diuretic activity was observed with aqueous extract of B.vulgaris roots. The diuretic potential of C.nucifera roots extract was statistically significant (p< 0.05) at dose 300mg/kg and comparable to that of the standard drug furosemide (20mg/kg i.p.).

 

 

INTRODUCTION:

Diuretics are the drugs that increase the rate of urine flow and sodium excretion. Drug induced dieresis is  beneficial in many life threatening disease conditions such as congestive heart failure, nephritic syndrome, cirrhosis, renal failure, hypertension, and pregnancy toxaemia¹. Plant medicine is commonly used in the traditional treatment of some renal diseases, and many plants are reported possess significant diuretic activity². It is well known that plant medicines have very little or no side effects as compared to the allopathic drugs. Hence search for a new diuretic agent that retains therapeutic efficacy and yet having minimum side effects is justified.

 

Cocos nucifera Linn (Family: Palmae) known as coconut palm; is extensively cultivated in southern India and Ceylon.  It is the only species in the genus Cocos, and is a large palm, growing to 30 m tall, with pinnate leaves 4-6 m long, and pinnae 60-90 cm long³.

 

The entire plant is important and traditionally used in treatment of urinary disorders, thirst, burns, and fever and as diuretic, astringent and antiseptic⁴.The water of coconut reported to have antioxidant properties⁵. Bambusa vulgaris Schrad ex J.C.Wendl. (Family: Poaceae) commonly known as Bamboo; is wild throughout India, in hill forest of West and South India. It is usually planted in gardens as an ornamental plant. From ancient days roots are used as diuretic, laxative, astringent and for cooling actions. The decoction of roots is taken internally to promote the flow of urine⁶. Anti-inflammatory activity has been reported to the leaves of this plant⁷.

 

Literature survey revealed that these plants root extract has yet not been screened for their traditional diuretic activity in experimental animals. Therefore the present study was carried out to provide pharmacological evidence for the folklore medicinal consideration of these plants as diuretic.

 

MATERIALS AND METHODS:

Animals:

Adult Wister rats of either sex, weighing 160-180gm were procured from the central animal facility of the Institute. The animals were housed in standard polypropylene cages (three rats/cage) and maintained under the standard conditions: room temperature (25±3)°C, humidity 45%–55%, 12 /12 hours-light/dark cycle. They were fed with commercially available rat normal pellet diet (NPD) (Pranav Agro Industries Ltd, Sangli, India) and water ad libitum, prior to the dietary manipulation. The experimental protocol was approved by the Institutional Animal Ethics Committee of Tatyasaheb Kore College of Pharmacy, Warananagar, MS, India and was in accordance with the guidelines of the Committee for the Purpose of Control and Supervision of Experiments on Animals (CPCSEA), Govt. of India.

 

Plant material:

The roots of C.nucifera and B.vulgaris were collected from Warananagar and Kodoli region of Kolhapur district and were authenticated by Dr. Ashok S. Nigwekar, Head, Department of Botany, Bhogavati mahavidyalaya, Bhogavati, MS, India.

 

Preparation of extract:

Roots of C.nucifera and B.vulgaris were collected and washed thoroughly with water and air dried in shade at room temperature. Then they were mechanically powered and sieved. For aqueous extract, 250 g powder of coconut roots were macerated with 1000 ml of distilled water and 250 g powder of Bamboo roots were macerated with 1000 ml of distilled water for 3 days with intermittent stirring. Then they were filtered. The filtrate was concentrated over the vapor of the water bath and dried under vacuum. The yield of extract was 8.94% w/w and 11.13% w/w for C.nucifera and B.vulgaris respectively.

 

Drugs and chemicals:

All the chemicals and reagents were procured from S.D.Fine Chemicals, Mumbai, India. All the chemicals were of analytical grade. Furosemide was used as reference drug.

 

Phytochemical investigation:

The preliminary phytochemical screening of aqueous extracts of both C.nucifera and B.vulgaris was carried out to determine the nature of phytoconstituents present in it. The results of preliminary phytochemical investigation are shown in table 1.

 

Acute toxicity study:

Acute toxicity study was performed in rats. The extracts were administered orally at doses of 175, 550, 2000 mg/kg. Animals were observed for signs of toxicity, continuously for 2 h, and for mortality up to 48 h, after oral administration of different doses of extract⁸.

 

Experimental protocol:

Grouping and drug treatment:

The animals were divided into 8 groups (each containing 6 animals), were deprived and fasted of water for 18 h prior to experiment. On the day of experimentation, rats of group 3, 4 and 5 were administered with aqueous extract of B.vulgaris roots (AEBV) 100, 200 and 300 mg/kg p.o. respectively. Group 6, 7 and 8 were treated with aqueous extract of C.nucifera roots (AECN) 100, 200 and 300mg/kg p.o. resp. The first group received vehicle (normal saline 25ml/kg p.o.) served as control and the second group served as the standard group, received furosemide (20 mg/kg, i.p.). All the extracts were dissolved in normal saline.

 

Diuretic activity:

The method described by Lipschtiz et al⁹ and Kavimani et al¹⁰, was employed for the evaluation of diuretic activity. Immediately after extract or drug administration, each animal was placed in an individual metabolic cage specially designed to separate urine and fecal matter and kept at room temperature (25±0.5^oC). During the period of study no food, water was made available to the animals. The total volume of urine was collected and measured from control, standard and extract treated groups up to 5 h of administration. The parameters monitored for the each individual rat were total urine volume and urine concentration of Na⁺, K⁺ and Cl^-. The Na ⁺ and K⁺ concentration were measured by flame photometry and Cl^- concentration was estimated as NaCl by titration with silver nitrate solution (2.096 g/l) using one drop of 5% potassium chromate solution as indicator¹¹. The ratio of the concentration of Na⁺/K⁺ and diuretic index at the end of 5h, were calculated to assess the diuretic potential of the root extracts of C.nucifera and B.vulgaris.

 

Statistical analysis:

All values are expressed as mean ± SEM. Data was analyzed using a statistical package (InStat software, San Diego California, USA). Comparisons between various groups were made using a one-way analysis of variance (ANOVA) followed by Tukey’s multiple comparison test. P<0.05 was considered as statistically significant.

 

RESULT AND DISCUSSION:

In the present study, aqueous extract of the C.nucifera and B.vulgaris roots were subjected to the preliminary phytochemical screening. These tests revealed the presence of saponin glycosides, amino acids, and proteins in the aqueous extract of the C.nucifera roots and flavonoids, saponin glycosides, amino acids, and proteins in the aqueous extract of the B.vulgaris roots. [Table 1]. From acute toxicity studies, it was observed that both extracts were safe in the doses used and there was no mortality up to a dose of 2000 mg/kg, p.o. Therefore doses nearer to 1/10^th of the maximum tolerated dose were chosen for further studies.

 

Oral administration of the aqueous extract of C.nucifera and B.vulgaris roots increased the urinary output in a dose dependent manner. But this increase was not statistically significant in case of B.vulgaris root extract. However significant diuretic activity was observed with  C.nucifera root extract at all the three doses tested. Extract exhibited a cumulative diuretic effect similar to Furosemide at a dose of 300mg/kg (P<0.05). [Table 2]. There was no significant change in the urine pH in all the groups tested.

 

Table 1: Phytochemical constituents present in aqueous extract of B.vulgaris and C.nucifera roots

 

Chemical constituents	Aqueous extract  of the C.nucifera roots	Aqueous extract  of the B.vulgaris roots
Flavonoids	-	+
Glycosides	-	-
Steroids	-	-
Saponin glycosides	+	+
Alkaloids	-	-
Proteins and amino acids	+	+

 

Table 2: Effect of oral administration of B.vulgaris and C.nucifera root extracts on urinary volume, electrolytic excretion and pH:

 

Treatment (mg/kg. p.o.)	Urine vol. ml/5h	Urine pH	Total  Na+ (mEq/L)	Total  K+ (mEq/L)	Total  Cl- (mEq/L)	Na+ /K+ ratio	T/C
Normal Saline	6±0.2	6.55±0.13	125±3.12	70.63±1.73	300.16±10.91	1.77	---
Furosemide-20	12.1±1.34	7.28±0.87	361.4±11.74	130.46±1.89	1001.8±7.74	2.77	2.05
AEBV-100	6.2±0.5	6.44±0.53	130.66±6.01 ns	72.2±2.04 ns	319.53±1.73 ns	1.80	1.03
AEBV-200	6.5±0.7	6.81±0.04	134.8±7.48 ns	75.76±2.61 ns	340.9±7.18 ns	1.77	1.08
AEBV-300	7.05±0.5	6.80±0.9	144.3±8.13 ns	77.9±3.87 ns	346.36±7.28 ns	1.85	1.16
AECN-100	9.2±1.1***	6.77±0.43	252.26±6.81***	215.26±2.76#***	719.33±10.72***	1.17	1.53
AECN-200	10.3±1.2***	6.92±0.56	320.46±4.74***	259.66±2.65#***	840.4±7.46***	1.23	1.71
AECN-300	12.5±1.7#***	7.00±0.28	379.93±8.67#***	279.86±4.85#***	962.4±9.50#***	1.35	2.08

Values are mean ± S.E.M. The abbreviations denote AEBV: Aqueous extract of B.vulgaris roots, AECN: Aqueous extract of C.nucifera roots. #p<0.05vs Std; *** p <0.001 vs normal control,      ns: not significant, T - Urine volume collected for extract, C - urine volume collected for control. T/C: Diuretic Index.

 

 

Significant change was not observed with the excretion of Na⁺, K⁺ and Cl^‑ after administrating extract of B.vulgaris, where C.nucifera root extract at all the three doses showed a significant increase in excretion of these ions in a dose dependent manner. The decrease in the ratio of concentration of excreted Na⁺ and  K⁺  for the tested extract of C.nucifera, compared to control, indicates that the extract does not increases  Na⁺  excretion to a greater extent. These results revealed the diuretic nature of the C.nucifera with higher hyperkalaemic side effect.

 

One of the earliest strategies for the management of hypertension was to alter a balance by restriction of salt in the diet. Diuretic agents having antihypertensive effects were used alone and had greater efficacy¹. Diuretics relieve pulmonary congestion and peripheral edema. These agents are useful in reducing the syndrome of volume overload, including orthopnea and paroxysmal nocturnal dyspnoea. They decrease plasma volume and subsequently venous return to the heart (preload). This decreases cardiac workload, oxygen demand and plasma volume, thus decreasing blood pressure¹². Thus, diuretics play an important role in hypertensive patients.

 

The results obtained in the study indicate that C.nucifera root extract act as effective hypernatremic, hyperchloremic, hyperkalemic diuretic and it can be used as antihypertensive.

 

CONCLUSION:

From the study on B.vulgaris and C.nucifera root extract it is concluded that, B.vulgaris does not possesses significant diuretic activity, where C.nucifera root extract has significant effects on urinary excretion of electrolytes and support the folklore consideration of C.nucifera plant roots as diuretic and antihypertensive.

 

REFERENCES:

1)       Koti BC, Purnima A. Diuretic activity of extracts of Centratherum anthelminticum. Int J Green Pharm. 2008; 2(4): 228-231.

2)       Nalwaya N. et al. Diuretic activity of a herbal product UNEX. Int J Green Pharm. 2009; 3(3): 224-226.

3)       Varier PS. Indian medicinal plants. Orient longman, Chennai.1994.

4)       Nadkarni KM. Indian materia medica. Popular prakashan, Mumbai.1982.

5)       Mantena SK.et al. In vitro evaluation of antioxidant properties of Cocos nucifera Linn. water. Food.2003; 47(2):126-131.

6)       Kurian JC. Plants that heal. Oriental Watchman Publishing House, Pune. 2003.

7)       Carey WM.et al. Anti-inflammatory activity of methanolic extract of Bambusa vulgaris leaves. Int J Green Pharm. 2009; 3(3): 234-238.

8)       Ghosh MN. Fundamentals of experimental pharmacology. Scientific book agency, Calcutta.1984.

9)       Lipschitz WL, Hadidian Z and Kerpcar A. Bioassay of diuretics. J Pharmacol Exp Ther. 1943; 79:97-110.

10)    Kavimani S. et al. Diuretic activity of aqueous extract of Orthosiphon thymiflorus in rats. Indian J Pharm Sci. 1997; 64:96-98.

11)    Beckette AH and Stenlake JB. Practical Pharmaceutical Chemistry, Part-1. CBS Publishers and Distributors, New Delhi.1997.

12)    Hoeland RD, Mycek MJ. Lippincott's illustrated reviews: Pharmacology. Lippincott Williams and Wilkins, Philadelphia. 2000.

 

 

Received on 31.03.2010       Modified on 23.04.2010

Accepted on 29.05.2010      © RJPT All right reserved