Carbohydrate Polymers 96 (2013) 253–258 Contents lists available at SciVerse ScienceDirect Carbohydrate Polymers jo ur nal homep age: www.elsevier.com/locate/carbpol Isolation and partial characterization of delayed releasing starches of Colocasia species from Jharkhand, India V. Deepika, K. Jayaram Kumar ∗ , P. Anima Department of Pharmaceutical Sciences, Birla Institute of Technology, Mesra, Ranchi, Jharkhand 835215, India a r t i c l e i n f o Article history: Received 30 December 2012 Received in revised form 2 April 2013 Accepted 4 April 2013 Available online 10 April 2013 Keywords: Starch In vitro release Colocasia Amylose a b s t r a c t There is an increasing interest in starch manufactured from edible tubers for controlled delivery of drug. Starches of different cultivars of Colocasia from Jharkhand, North Eastern State of India, were isolated and their morphological, physicochemical, structural properties were studied. The yield of starches was estimated in the range of 6.46-13.75%. All the isolated starches revealed their irregular shape with a diameter of 5-10 m. There was considerable variation in amylose content, swelling and solubility power, water hydration capacity. FTIR spectra confirmed their carbohydrate nature. Powder studies revealed that these starches possess potential for pharmaceutical industries. In vitro release data revealed the delayed release of all tablets made by using Colocasia starches at pH 6.8 and 7.4 when compared with maize starch. Delayed release of all starches showed there is a great potential to be used these starches as pharmaceutical excipient in sustained release dosage form with minimum modification. © 2013 Elsevier Ltd. All rights reserved. 1. Introduction Starch is considered as important material used in both food and non food industries. Tubers are important sources of starch and are used as staple food in tropical and sub-tropical countries (Liu, Donner, Yin, Huang, & Fan, 2006) In North East India, starchy tubers such as potato (Solanum tuberosum) is grown in winter, taro (Colocasia and Xanthosoma spp.) and Amorphophallus spp. (grown widely) are produced in the rainy summer (March–August) (Saikia & Konwar, 2012). Recent advances in the research of the food prop- erties revealed the use of food and its constituents such as starch, cellulose and gums, for the controlled delivery of drugs without any modification in their natural form. Studies on Colocasia starch from Jharkhand, India are not well documented. Colocasia species origi- nated from the North Eastern region of the country and distributed to other parts of India (Kuruvilla & Singh, 1981). Jharkhand is one of the North Eastern regions of India in which this tuber is culti- vated and is locally known as “kachalu” or “kachu” and “arbi” or “arvi”. The tubers of this tropical plant belonging to Araceae fam- ily and has high starch content that ranges between 22% and 40% (Agbor & Rickard, 1990; Delpeuch, Favier, & Charbonniere, 1978). This tuber is less commercialized at present. Advancement in agro- nomic techniques and utilization of modern genetic techniques may allow this tuber to be cultured and commercialized. However, ∗ Corresponding author. Tel.: +91 06512276247; fax: +91 06512275290. E-mail addresses: jayaram.res@yahoo.com, jayarampharm@gmail.com (K. Jayaram Kumar). this tuber has a short shelf life because of its high moisture con- tent. One of the best ways to preserve the tuber is by processing them to obtain flour and/or starches. As compared to other tuber starches like potato, starches obtained from Colocasia tuber have never been commercialized because their properties are unknown. Since the transformation into starch will decrease losses after the tubers have been harvested. A significant amount of work remains to be done on the characteristic properties of Colocasia (Satin, 1999). Before consideration Colocasia as potential source of starch to use in food and non food industries, it is necessary to characterize their chemical composition, physical, physicochemical, and functional properties. Moreover, uses of starch from Colocasia tuber are less explored in drug delivery as excipient. These can be used as disinte- grant and binder. This paper therefore reports the results of a study undertaken to determine the characteristic properties of native starch isolated from taro tubers grown in Jharkhand, North eastern Region of India to increase its potential in food industries and also reported release characteristic of isolated starches in physiological environment to enhance their uses in pharmaceutical industries as excipient. 2. Materials and methods 2.1. Starch isolation Different cultivars of Colocasia esculenta L. Schott (CA 1 , CA 2 , and CA 3 ) were purchased from the local market of North Eastern Region of India, Jharkhand. One kilogram of each tuber were thor- oughly washed, peeled and sliced into pieces. Starch was isolated by 0144-8617/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.carbpol.2013.04.002