MICROWAVE ASSISTED ISOLATION OF MUCILAGE FROM THE TRICHOSANTHES DIOICA FRUIT

MICROWAVE ASSISTED ISOLATION OF MUCILAGE FROM THE TRICHOSANTHES DIOICA FRUIT

1. N. Shah ¹*, A. K. Seth ² and B. S. Nayak ¹

Vidyabharti Trust College of Pharmacy ¹, Umrakh, Gujarat, India

Sumandeep Vidyapeeth University ², Piperia, Gujarat, India

ABSTRACT

Objective: A microwave assisted extraction technique was developed to optimize the extraction of mucilage from the fruits of Trichosenthes dioica plant. Materials and Methods: the plant has been extracted by conventional and microwave assisted methods for the isolation of mucilage. Results and Discussion: Microwave extraction at 320 W intensity and 20 min heating duration, 84.92% increase in the yield of mucilage while 52.06% and 38.09% increase in the yield at 640 W for 5 min and 160 W for 40 min respectively were obtained under microwave irradiation when compared to 1 h conventional heating method. The products obtained by both the methods were of similar nature both physically and chemically. Conclusion: The developed microwave procedure can be used successfully in commercial and routine laboratory isolation of mucilage.

INTRODUCTION: In the past few years, microwave heating has been found to be a convenient source of energy not only in kitchen, but also in chemical laboratories¹. Many of the basic principles of green chemistry are best suited for microwave processes². It is one of the simple, fast, clean, eco-friendly and efficient method. It is economic in saving energy, fuel and electricity.  A very short response time and better yields of the products are the main advantages of microwave heating. Commercial microwave ovens are used as a source of energy in chemical laboratories for efficient heating of water, moisture   analysis, wet ashing of biological and geological materials, waste material management, sterilization of pharmaceutical preparations, inactivation of enzymes in food products, etc.

In the past few years, a large number of reports have appeared on the use of this technique in acceleration of organic reaction for rapid and green synthetic procedures¹. Extraction  is  one  of  the  most  crucial  point  in  the analytical chain in the effort of achieving a complete recovery of target compounds. Recently, microwave energy is being used for extraction of phytoconstituents from plants ^{3, 4}. Microwave extraction follows the same principle as maceration or percolation, but the speed of breaking up of plant cells and plant tissues is much higher. This reduced processing time is an economic advantage and also there is less risk of decomposition or disintegration and oxidation of the valuable plant constituents. Microwave assisted extraction methods require shorter time, less solvents, higher extraction rate and better products with lower costs ⁴. The microwave consists of a number of radiation chambers in order to manipulate the required energy. The energy requirement can be controlled much better than with conventional thermal energy. A great deal of work is required to standardize experimental procedures using this technique.

Today, the whole world is turning towards finding suitable alternatives for the synthetic compounds used in pharmaceutical industries from natural sources². The synthetic polymers used as excipients suffer from many disadvantages such as high cost, toxicity, non- biodegradability and environmental pollution caused during their synthesis ⁵.

Natural polymers like mucilages and pectins are easy to isolate, purify and are non-toxic and biocompatible. They are biodegradable and will not cause environmental pollution⁵. They are found as common ingredients in cosmetic, food and non-food industries. They are used as binding, thickening, emulsifying, suspending and stabilizing agents in pharmaceutical industries and used as matrices for sustained release of drugs, because of their higher water swellability, non-toxicity, low cost and free availability ⁵.

Conventionally, mucilages are isolated by heating for 1 h, in aqueous solvents^5,6. In order to reduce the duration involved in their extraction and study the yield, mucilage from the fruits of Trichosanthes dioica plant was isolated in the present study using microwave method.

MATERIALS AND METHODS:

Collection and Authentication: The fruits of Trichosanthes dioica (Cucurbiteace) plant were used for the isolation of mucilage. These materials were collected from the local market of Bardoli, Gujarat and authenticated by Botanist from Science College Bardoli. The voucher specimen was kept in the college museum.

Isolation of Mucilage by Conventional Procedure: Trichosanthes dioica fruit (5 g) were powdered for 5 min in a mechanical blender and soaked in distilled water (150 ml) for 24 h in a RB flask. It was boiled for 1 h under reflux with occasional stirring and kept aside for 2 h for the release of mucilage into water. The material was filtered through a muslin bag and hot distilled water (25 ml) was added through the sides of the marc and squeezed well in order to remove the mucilage completely.

Equal volume of ethanol was added to the filtrate to precipitate the mucilage and kept inside a refrigerator for one day for effective settling. It was filtered and dried completely in an incubator at 37º C, powdered and weighed. It was subjected to chemical tests to confirm its identity ^{6, 7}.

Isolation of Mucilage by Microwave Procedure: Trichosanthes dioica fruit (5 g) were powdered in a mechanical blender for 5 min and soaked in distilled water (150 ml) for 24 h in a 1000 ml beaker. It was kept in a microwave oven (LG Grill Intello wave System, Model No. MG-2381LE) along with a glass tube inside to prevent bumping. It was subjected to microwave irradiation at 800 W intensity for 3 min. The beaker was removed from the oven and kept aside for 2 h for the release of mucilage into water.

It was processed in a similar way as explained in the conventional procedure, weighed and chemical tests were carried out. The experiment was repeated several times using various intensities and different durations as shown in Table 1. In each case, the yield was calculated.

RESULTS AND DISCUSSION

Using Trichosanthes dioica fruit for the isolation of mucilage, microwave standardization was carried out at several intensities and durations (Table 1). Using 320 W intensity and 20 min heating duration, 84.92% increase in the yield of mucilage while 52.06% and 38.09% increase in the yield at 640 W for 5 min and 160 W for 40 min respectively were obtained under microwave irradiation when compared to the conventional heating method.

Table 1: Standardization of microwave method for the isolation of mucilage from Trichosenthes dioica fruit

*In comparison to conventional method

The mucilage isolated by both the methods was found to be identical in nature and gave positive results for all the chemical tests performed. Thus, the selected plant source produced high yield of mucilage in shorter duration by the developed microwave method when compared to conventional heating. In recent years, modern techniques are effectively being used for the extraction and isolation of phytoconstituents.

Ways to minimize the consumption of energy and developing efficient isolation and purification processes is of utmost global importance today. Plant mucilages are found as common ingredients in cosmetic, pharmaceutical, food and non-food industries due to their low cost compared to the synthetic polymers⁸. In view of the rising costs and fluctuations in availability of the synthetic polymers, scientists are engaged in finding suitable alternatives to these⁹. Such an effort would be welcomed both locally and internationally. In India, only few units are manufacturing mucilages on commercial scale. USA, Switzerland and other European countries are producing these in large scale. Most of the Indian needs are mainly met by import. The conventional isolation of mucilages from plants consumes more time and gives low yields. Hence, the cost of production of these is increasing.

In the present study, mucilage was isolated in high yields and in lesser durations by the developed microwave method when compared to the conventional heating. Same quantities of raw materials were used for both the methods. The developed microwave methods save 20 and 40 min heating duration respectively, for the isolation of mucilage. The speed of breaking up of plant cells and plant tissues is much higher under microwave conditions⁴. The present study also proves the same.

CONCLUSION

In the present study, a microwave assisted method for rapid extraction of mucilage from Trichosanthes dioica fruit has been optimized. The developed method improved the yield of mucilage from the selected source. In conclusion, the developed microwave procedure can be used successfully in commercial and      routine            laboratory isolation of mucilage.

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