INTRODUCTION:

Ideally, Lemongrass leaves will retain their green color. Lemongrass leaves should be dried as soon as possible within 24 hours and a conventional dryer may be used for this. An extended drying period, such as in the case of it being left out in the sun to dry, will cause the leaves to lose color and the aroma quality to diminish ^[1]. Once harvested, leaves may be stored in shade for up to 3 days without the oil yield or quality being compromised. The Lemongrass is then steam distilled^[2].

Table 1: Uses and benefits of leamon grass oil ^{[3] [4]}

Cosmetics

Odorous

Medicinal

Antimicrobial

Astringent

Deodorant

tonic

Antidepressant

Antimicrobial

Antipyretic

Bactericidal

Sedative

Tonic

Nervine

Febrifuge

Analgesic

Antimicrobial

Antipyretic

Antiseptic

Carminative

Diuretics

Fungicidal

tonic

Contraindications for Lemongrass Oil:^[5]

As with all other New Directions Aromatics essential oils, Lemongrass Essential Oil should never be ingested due to its toxicity. It is imperative to consult a medical practitioner before using Lemongrass Essential Oil for therapeutic purposes. Pregnant and nursing women and those taking prescription drugs as well as those with liver or kidney disease are especially advised not to use Lemongrass Essential Oil without the medical advice of a physician. The oil should always be stored in an area that is inaccessible to children, especially those under the age of 7. Due to its high Citral content, Lemongrass may potentially burn skin, thus prior to using Lemongrass Oil a skin test is recommended. This can be done by diluting the essential oil in carrier oil, such as Coconut, Olive or Jojoba oils, and applying a small amount to a small area of skin that is not sensitive. Once applied topically, sun exposure should be avoided, as Lemongrass Oil may sensitize the skin to UV rays. Lemongrass Oil must never be used near the eyes, inner nose, and ears, or on any other particularly sensitive areas of skin.

Possible side effects caused by the topical use of Lemongrass Essential Oil include a burning sensation, discomfort, rashes, or skin irritation. Use of Lemongrass Essential Oil is inadvisable for those who are diabetic or hypoglycemic. Using this essential oil could possibly lead to lowered blood glucose and could have negative side effects for those who take oral diabetes drugs or medications to treat hypertension (high blood pressure).

MATERIALS:

Carbopol 934

Carbopol® 934 polymer is a white powder, cross-linked polyacrylic acid polymer. It exhibits short flow properties and a creamy sensory profile, and is therefore well suited for use as a rheology modifier in lotions and creams.

Glycerine:

Glycerol is generally obtained from plant and animal sources where it occurs as triglycerides. Triglycerides are esters of glycerol with long-chain carboxylic acids. The hydrolysis, saponification, or transesterification of these triglycerides produces glycerol as well as the fatty acid deriva Methyl paraben is an anti-fungal agent often used in a variety of cosmetics and personal-care products. It is also used as a food preservative and has the E number E218.

Methyl paraben:

Methyl paraben is commonly used as a fungicide in Drosophila food media. To Drosophila, methyl paraben is toxic at higher concentrations, has an estrogenic effect, and slows the growth rate in the larval and pupal stages at lower concentrations.

Triethanolamine:

Trolamine, which is also referred to as triethanolamine (TEA), is a tertiary amine and a triol. It is a bifunctional compound that exhibits both properties of alcohols and amines. Trolamine contains small amounts of diethanolamine and ethanolamine and may also act as an antioxidant against the auto-oxidation of animal and vegetable fats [A27174]. It is commonly used as a pH adjuster and surfactant in industrial and cosmetic products such as skin and hair conditioning products.

PEG 4000:

PEG is soluble in water, methanol, ethanol, acetonitrile, benzene, and dichloromethane, and is insoluble in diethyl ether and hexane. It is coupled to hydrophobic molecules to produce non-ionic surfactants. PEG is the basis of a number of laxatives. Whole bowel irrigation with polyethylene glycol and added electrolytes is used for bowel preparation before surgery or colonoscopy.

PEG is also used as excipients in many pharmaceutical products.

Table 2: Formulation table

Sr. No.	Ingredients	Quantity	Role
1	lemon grass oil	2 mg	active ingredients
2	carbapol 934	1 gm	polymer
3	PEG4000	5ml	polymer
4	Glycerin	15 ml	Humectant
5	methyl paraben	200 mg	Preservative
6	triethanolamine	1ml	gelling agent
7	distilled water	qs	vehicle
8	Orange oil	qs	Flavouring agent

Procedure:

1. Weighed amount of Carbapol 934 was soaking for one day in 10 ml distilled water

2. Carbapol 934 was homogenized in homogenizer.

3. Mix other ingredients [lemon grass oil, PEG4000, glycerin, methyl paraben, water] properly in another beaker.

4. Then add the above mixture in homogenized carbapol 934.

5. Then add required amount of triethanolamine.

6. Then homogenize the above mixture, add orange oil and formation of gel.

Evaluation of formulations

1. Physical Evaluation:

Physical parameters such as colour and consistency were checked visually.

2. Washability:

Formulations were applied on the skin and then ease and extend of washing with water were checked manually.

3. pH:

pH of 1 % aqueous solution of formulation was measured by using a calibrated digital pH meter at constant temperature.

4. Spreadability:

The apparatus consist of wooden block with a fixed glass slide and movable glass slide with one end tied to weight pan rolled on the pulley, which was in the horizontal level with fixed slide. The spreadability of the formulated gel was measured on the basis of ‘Slip and Drag’ characteristic of gel. An excess of gel (about 2 gm) under study was placed on this ground slide. The gel was then sandwiched between two slides. 500 gm weight was placed on the top of the two slides for 5 min. to expel air and two provide a uniform film of the gel between the slides. Excess of the gel was scrapped off from the edges. The top plate was then subjected to pull of 80 gm. Mix with the help of string attached to the hook and the time (T in sec) required by the top slide to move a distance of 6.5 cm be noted. A shorter interval indicated spreadability.

Fig. 1: Spreadability apparatus

Formula:

Spredability(S) = M*L/t (cm.gm/sec)

Specifications;

Weight of sample = 2.5 gm

Weight applied on upper plate = 5gm

Weighttighed to thread = 80gm

Distance travelled by upper plate = 6cm

Time required to cover distance = 23 sec.

5. Anti microbial activity ^[6]

Nutrient agar is a general purpose medium supporting growth of a wide range of non-fastidious organism. It typically contains (mass/volume)

· 0.5% Peptone- this provides organic nitrogen

· 0.3% Beef extract/yeast extracts-the water soluble content of these contribute vitamins, carbohydrates, nitrogen, and salts.

· 1.5% agar - This gives the mixture solidify

· 0.5% sodium chloride-this gives the mixture proportions similar to those found in the cytoplasm of most organisms.

· Distilled water-Water serves as a transport medium for the agar's various substances

· pH adjusted to neutral (6.8) at 25⁰C.

· These ingredients are combined and boiled for approximately one minute to ensure they are mixed and to sterilize them. Then they are cooled to around 50⁰C (122⁰F) and poured into Petri dishes which are covered immediately. Once the dishes hold solidified agar, they are stored upside down and are often refrigerated until used. Inoculation takes place on warm dishes rather than cool ones: if refrigerated for storage, the dishes must be rewarmed to room temperature prior to inoculation.

The antibacterial activities of different formulations were determined by modified Agar well diffusion method. In this method, nutrient agar plates were seeded with 0.2ml. 24 hrs of broth culture of Bacillus, a causative organism. The agar plates were allowed to solidify. A sterile 8mm borer was used to cut Wells of equidistance in each of the plates .0.5ml of formulations, herbal extract gel were introduced into the walls at randomly. The plates were incubated at 37⁰C for 24hrs. The antibacterial activities were evaluated by measuring the zones of inhibition (in mm). the results of evaluation are shown in table.

Fig. 2: Anti microbial activity

6. Franz diffusion cell study:

The experiments were conducted in Franz diffusion cell with donor compartment and receiver compartment. A suitable size of pretreated cellophane membrane was mounted in between donor and receptor cells of Franz diffusion cell (locally fabricated). The receiver contains 25ml phosphate buffer solution (PBS). PBS pH 6 was constantly stirred by magnetic stirrer at 50 rpm and was maintained at a temperature of 37⁰c throughout the experiment. A formulation that is drug equivalent to 2mg was applied homogeneously in the donor compartments 1ml sample were withdrawn from receiver at predetermined time intervals over 30min. and immediately replenished with an equal volume of fresh PBS samples were assayed for drug content spectrophotometrically. Sink condition was maintained throughout the experiment.

Fig. 3: Franz diffusion cell study

RESULTS:

Table 3: Observation table

Sr. No	Concentration µgm/ml	Time Min.	absorbance	Drug release	Percent drug release
1	2	5	0.2178	0.3625	18.12%
2	4	10	0.2967	0.526	26.30%
3	6	15	0.3134	0.56	28.00%
4	8	20	0.5793	4.444	55.50%
5	10	25	0.8452	1.735	86.87%
6	12	30	0.9252	1.820	91.00%

Table 4: Observation table

Test	Inference
Physical evaluations	Good
Washability	Good
pH	6
Spreadability	Good
Antimicrobial activity	Good
Franz diffusion cell study	% Drug release91.00%

CONCLUSION:

From the obtained results we can connclude that we can use lemongrass oil against Staphylococcus aureous. When the formulated herbal gel were kept at room temperature (28º-30ºC) and under accelerated condition (45ºC) then it remain stable.

REFERENCE:

1. Berry MJ. Antimicrobial activity of essential oil of local Serai Cymbopogon citratus. Journal of Bioscience, 2004; 3: 87-90.

2. Awogbeni O., and Ogunleye IO. Some selected vegetables. International Journal of Engineering Technology, 2009; 1: 1793-8236.

3. Blanco MM., Costa CA., Costa M., Freire AO., and Santos JG. Neurobehavioral effect of essential oil of Cymbopogon citratus in mice. Phytomedicine, 2009; 16: 265-270.

4. Kerala Agriculture University Aromatic and Medicinal Plants Research Station Odakkali, Asman Knoor-683562, Ernakulam, Dist. Kerala India.

5. Cuervo-Andrade A. Quality oriented drying of lemongrass balm (Melissa officinalis L.). University of Kassel. Ireland, 2011; 49-53.

6. Berry MJ. Antimicrobial activity of essential oil of local Serai Cymbopogon citratus. Journal of Bioscience, 2004; 3: 87-90.

Received on 05.12.2018 Modified on 10.02.2019

Res. J. Pharma. Dosage Forms and Tech.2019; 11(2):67-70.

DOI: 10.5958/0975-4377.2019.00010.7