Shelf-life evaluation of Kaṃsaharītakī avaleha and its granules: A preliminary study.

BACKGROUND: Savīryatā-avadhi (shelf life) of different Ayurvedic dosage forms is described in Śārṅgadharasaṃhitā. Though the concepts have a strong background, we seek to re-evaluate the age old concepts by following current norms. An attempt has been made in the present study to evaluate shelf-life of Kaṃsaharītakī avaleha and its granules.
MATERIALS AND METHODS: Raw materials were procured from Pharmacy, Gujarat Ayurved University, Jamnagar and utilized after proper authentication in pharmacognosy lab. The avaleha and its granules were prepared in the departmental laboratory following classical guidelines and subjected to accelerated stability studies.
RESULTS: Both the products were found to be free from microbial contamination. Heavy metals were within the prescribed limit. Changes in physico-chemical profiles at different intervals are insignificant. On extrapolation of the observations, the shelf life of avaleha was found to be18 months and 27 months to the granules.
CONCLUSION: Stability of granules was found to be comparatively higher than the avaleha. This observation may be exclusive to Kaṃsaharītakī avaleha. Studies on other avalehas and their granules need to be carried out to confirm this preliminary observation.

INTRODUCTION

The time period during which the potency (vīrya) of a drug remain unaffected due to environmental factors or from microbial contamination is termed as “shelf life.”[1] Contemporarily another term, “expiry date,” which is the time period up to which a substance possess full safety and potency is used. But there is difference between shelf life and expiry date. A dosage can be safe after passing the shelf life, but may be of reduced potency. Whereas, in case of expiry date, there is no guarantee of both safety and efficacy after expiry.

Significance of shelf-life is highly appreciated and recognized in classical texts like Carakasaṃhitā, but the information is scattered. It has been said that the drug can be utilized for therapeutic purposes until it retains its fragrance, color, and taste etc.[2] The shelf life period finds mention after 12th century AD in Vaṅgasena,[3] Śārṅgadharasaṃhitā,[4] and Yogaratnākara,[5] etc.

Though general information is available, exact shelf life of individual formulations is not available. Considering this, an attempt has been made to evaluate shelf life of Kaṃsaharītakī avaleha and its granules.

MATERIALS AND METHODS

Raw drugs

All the herbal drugs and madhu (honey) were procured from the Pharmacy, Gujarat Ayurved University, Jamnagar. Yavakṣāra was prepared in the dept. of Rasashastra and Bhaishajya Kalpana, Institute for Post Graduate Teaching and Research in Ayurveda, Jamnagar. Khaṇḍaśarkarā (sugar candy) and guda (jaggery) were procured from the local market of Jamnagar. All the herbal drugs were authenticated in the Pharmacognosy Laboratory.

Preparation of drugs

Kaṃsaharītakī avaleha (KHA)[6] and Kaṃsaharītakī granules (KHG)[7] were prepared by following standard guidelines. Ratio of ingredients were the same in both formulations but sugar candy and harītakī powder were used in place of jaggery and harītakī pulp respectively in KHG. Ingredients of KHA are given in Table 1.

Table 1

Formulation composition of Kaṃsaharītakīavaleha (KHA)

Sample quantity and packing

The final products (KHA and KHG) of 100 g each were packed in sterile glass containers (200ml capacity) and stored in an accelerated stability study chamber.

Storage conditions in the stability chamber

Samples were stored at 40°C ± 2°C, and 75% ±5% RH.

Frequency of withdrawal

The products were analyzed initially, and at a gap of 1, 3, 6 months.

Parameters of evaluation

Basic analytical parameters including total solid content,[8] moisture %,[9] ash value,[10] acid insoluble ash,[11] pH value,[12] water soluble extractives,[13] methanol soluble extractives,[14] total fats, total sugars,[15] microbial contamination,[16] heavy metals,[17] were evaluated at intervals specified earlier.

OBSERVATIONS AND RESULTS

The comparative organoleptic characters of the KHA and KHG are depicted in Table 2. Changes in the parameters at regular intervals were insignificant. Physico-chemical characters of the KHA and KHG at initial, 1, 3, 6-month interval were shown in Table 3. Microbial growth was found below prescribed limits in both drugs initially and after 6th month. Microbial count of KHG was less than KHA [Table 4]. Heavy metals in both samples were also found to be within the prescribed limits [Table 5].

Table 2

Comparative organoleptic characters of KHA and KHG

Table 3

Physico-chemical profile of KHA and KHG at different intervals

Table 4

Microbial growth in KHA and KHG

Table 5

Heavy metals in KHA and KHG

Based on this data; intercept and slope [Table 6] were calculated followed by expected time for 10% degradation for individual parameters [Table 7]. On extrapolation of the values, the shelf life of KHA was found to be 18 months and KHG as 27 months [Table 8].

Table 6

Intercept and slope of KHA and KHG for different parameters

Table 7

Approximate period (in months) for 10% degradation of KHA and KHG

Table 8

Extrapolation of shelf life in KHA and KHG

DISCUSSION

Concept of shelf-life is well defined in the classics of Ayurveda. Śārṅgadhara was the first to collect information and placed it under the heading of Savīryatā Avadhi. Śārṅgadhara opines that the avalehas start to lose their therapeutic potency after a year. According to Yogaratnākara, shelf life period of any avaleha is six months.[18] The Govt. of India Gazette specifies the shelf life of Granules and avalehas as 3 years.[19] In addition, Ayurveda acāryas also opine that the potency of a dosage form always depends upon the place, season, storage conditions etc. It infers that the shelf-life of medicinal preparations can be increased by taking specific care of all such factors. In addition to these factors; processing techniques such as granulation,[20] Bhāvanā[21] also increase shelf life. The present study is a preliminary attempt to develop an easy to use and stable dosage form of avaleha (electuary) preparations. Though the granule form is more stable, on comparison, no changes in organoleptic characters were found in both the drugs at different levels of storage. KHA was found to be brownish black in color with aromatic odor and bitter and astringent in taste. KHG was creamish brown in color with aromatic odor, bitter and astringent in taste. Difference in colour of both was due to the use of harītakī pulp and jaggery in avaleha while harītakī powder and sugar candy in granules. Granules were not prepared using Harītakī pulp and jaggery due to their stickiness.

Insignificant differences were observed in basic physico-chemical profiles in both the drugs at different stages of analysis. The moisture content of KHG was less than KHA which is one of the main parameters that determines the shelf life of a product. Moisture content is the main causative factor in deterioration. Moisture in a product is sufficient to activate different enzymes, which slowly decompose the product resulting in its degradation.[22] Granules have less microbial count, which indicates safety and quality of the product.

Principal component analysis (PCA) was adopted to analyze the variations in physico-chemical parameters of both samples. PCA is the most widely used multivariate analysis technique for transforming the original measurement variables into new variables called principal components (PCs). Each PC is a linear combination of the original measurement variables. it is possible to identify key relationships in the data, that is, find similarities and differences among objects in a data. PC1 shows more residual x-variance in Total solid content (TSC). Using principal component analysis (PCA) it is found that all data can be described with PC1 hence discrete variations were not found in samples and the data can be easily explained with a uni-variant model [Graph 1].

Graph 1

PCA of physicochemical data. (a) Scoring graph showing PCA of physicochemical data of samples: KHA and KHG (after 0, 1, 3 and 6 months). (b) Loading graph showing PCA of physicochemical data of samples: KHA and KHG (after 0, 1, 3 and 6 months). (c) Influence graph showing PCA of physicochemical data of samples: KHA and KHG (after 0, 1, 3 and 6 months). (d) Variance graph showing PCA of physicochemical data of samples: KHA and KHG (after 0, 1, 3 and 6 months) Parenthesis: ASH = Ash value, LOD = Loss on drying, AIA = Acid insoluble ash, TSC = Total solid content

CONCLUSION

Shelf-life of Kaṃsaharītakī avaleha is found to be 18 months, while its granules have shelf life of 27 months. This implies that the granules are more stable than the avaleha. This observation may be specific to Kaṃsaharītakī avaleha, as earlier studies with Vāsa avaleha and its granules reported vice versa. Studies involving many more avalehas and their granules are needed to substantiate the observations of the current study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.