Hemanta K. Sharma

Traditional medicinal plants in Mizoram, India

In rural societies of Mizoram, India, traditional methods of treatment are followed in the majority of the populace. Information on 135 plant species from 122 genera and 65 families is presented here.

Folklore medicinal plants of Nagaland, India

Abstract Traditional methods of treatment using plants and animals are predominant in rural societies of Nagaland, a state of North East India. As a result of an ethnobotanical survey conducted in 1993–1997, information on 36 such plant species from 35 genera and 28 families is presented.

Preparation and evaluation of the effect of particle size on the properties of chitosan-montmorillonite nanoparticles loaded with isoniazid

In this report, efforts have been made to develop isoniazid loaded chitosan-montmorillonite nanoparticles by ionic gelation of chitosan with pentasodium tripolyphosphate. The nanoparticles have been characterized by FTIR, XRD, SEM and TEM. The effect of surfactant and particle size on chitosan nanoparticles have been assessed with regard to swelling, encapsulation efficiency and release of isoniazid in different mediums. Swelling experiments provide important information on drug diffusion properties, which indicates that the chitosan nanoparticles are highly sensitive to the pH environment. The drug release mechanism has been studied during different time periods using a UV-visible spectrophotometer. Cytotoxicity has been assessed by MTT assay analysis. Mucoadhesion properties have been appraised by an in vitro wash off test and an ex vivo mucoadhesion test. The results imply that chitosan-montmorillonite nanoparticles can be exploited as potential drug carriers for controlled-release applications.

Formulation and in vitro evaluation of metformin hydrochloride loaded microspheres prepared with polysaccharide extracted from natural sources

The present work envisages utilisation of biodegradable and biocompatible material from natural sources for the development of controlled release microspheres of metformin hydrochloride (MetH). Natural polysaccharides extracted from Dillenia indica L. (DI), Abelmoschus esculentus L. (AE) and Bora rice flour were used in fabricating controlled release microspheres. The microspheres were prepared by the emulsion solvent diffusion technique with different proportions of natural materials and were studied for entrapment efficiency, particle size, particle shape, surface morphology, drug excipient compatibility, mucoadhesivity and in vitro release properties. The prepared microspheres showed mucoadhesive properties and controlled release of metformin hydrochloride. The study has revealed that natural materials can be used for formulation of controlled release microspheres and will provide ample opportunities for further study

Study on crosslinked gelatin-montmorillonite nanoparticles for controlled drug delivery applications

Gelatin, because of its biodegradability and ecofriendly nature, has been the best choice for controlled release applications. Montmorillonite (MMT) clay shows a very important role in controlling drug delivery. Hence, an attempt was made in this work to prepare gelatin–MMT nanoparticles by desolvation method using acetone as precipitating agent, glutaraldehyde (GA) as crosslinking agent, and water as reaction media for controlled delivery of isoniazid, a drug for tuberculosis. Characterization of the MMT and isoniazid-loaded gelatin–MMT nanoparticles was carried out using Fourier transform infrared spectroscopy, X-ray diffraction study, scanning electron microscopy study, and transmission electron microscopy study. The effect of MMT on gelatin nanoparticles was evaluated in terms of water uptake studies, and subsequently to the release of isoniazid drug in buffer solution at pH 1.2 (gastric pH) and pH 7.4 (intestinal pH). Swelling experiment indicated that the gelatin nanoparticles were very sensitive to the pH environment. The release profile of drug was studied by a UV–Visible spectrophotometer. Cytotoxicity study revealed that MMT-containing nanoparticles showed less cytotoxicity than MMT-free nanoparticles.

Carboxymethyl starch-chitosan-coated iron oxide magnetic nanoparticles for controlled delivery of isoniazid

Abstract Context: The coating material of magnetic nanoparticles plays a great role in drug delivery application. The coatings not only increase the stability of the nanoparticles but also improve the drug release pattern, biocompatibility and mucoadhesivity. Objective: Montmorillonite (MMT) containing magnetic iron oxide nanoparticles coated with polyelectrolyte complex (PEC) of carboxymethyl starch-chitosan were prepared for controlled release applications. Method: The PEC-coated nanoparticles were characterised by Fourier Transmission Infra-red spectroscopy and X-ray diffraction, scanning electron microscope, transmission electron microscope, and dynamic light scattering. Cytotoxicity study was performed by MTT assay analysis. Mucoadhesivity test was performed by using in vitro wash off and ex vivo method. Result: The coating of PEC showed good stability, biocompatibility and mucoadhesivity of the iron oxide magnetic nanoparticles. MMT addition enhanced the swelling, drug loading and release and also the cytotoxicity and mucoadhesivity of the nanoparticles. Conclusion: This study revealed that the MMT incorporated PEC of CMS-CS can be effectively used for coating of iron oxide nanoparticles.

Nanosized Drug Delivery Systems for Direct Nose to Brain Targeting: A Review

BACKGROUND Drug targeting to brain has always been problematic due to Blood-Brain Barrier (BBB), which, does not allow most of the drugs to pass through it as they are hydrophilic and macromolecular drugs. So, in order to bypass the BBB, alternative modes of administration were searched and nasal to brain delivery route was tried by many workers. Such studies yielded patented nano-formulations with the ability to cross blood brain barrier. METHODS Nanoparticles being smaller in size and large surface area help in increasing the rate of drug permeation to the brain. In this review work, emphasis has been laid on discussion on various works done in the field of nasal delivery of drugs to brain over the last decade. RESULTS The works that are discussed in this paper show better drug targeting of brain when given through nasal route as nanoparticles. Experiments performed in animal models have clearly exhibited that nano-sized formulations are able to facilitate the delivery of drugs to brain through nose in comparison to tantamount drug solutions. CONCLUSION However, it is not yet confirmed whether the drug is freed from the formulation in the nasal cavity and then absorbed or the nanoparticles themselves are absorbed and then the drug is released in the CNS. Furthermore, the toxicity studies were not carried out extensively in suitably designed model, which should be considered before going for further studies and application.

Chemical Composition and Antimicrobial Study of Essential Oil from the Leaves of Eupatorium odoratum Linn. From Upper Assam region

Abstract The essential oil from the dried leaves of Eupatorium odoratum Linn. was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). The major components were α-pinene (9.64 %), β-pinene, (4.85 %), germacrene D (20.27 %) , geijerene (25.10 %), trans-β- caryophyllene (10.04 %), and other components were presents in trace quantities. The leaf oil was screened for in vitro antibacterial activity and was tested against both gram positive and gram negative bacterial strains. The essential oil was found to be more active against E. coli (MIC=125 µg/ml) and B .Subtilis (MIC=62.5 µg/ml) respectively.

in vitro Evaluation of Leaves and Fruits of Elaeagnus latifolia L. for Antioxidant and Antimicrobial Activities

Antioxidants are the substances which delay, prevent or even inhibit the oxidation of oxidizable substrate/system in which they are present, by inhibiting the propagation or initiation of oxidative chain reactions [1]. They reduce themselves, thus acts as an antioxidant. Oxidizable substrate means very nearly everything found in the living cells counting proteins, lipids, DNA and carbohydrates [2]. Antioxidants possess free radical chain reaction breaking properties thus defend living cells against oxidative damage. They help in reducing and quenching of singlet oxygen formation and function as radical scanvengers [3-5]. Antioxidant activity is indispensable for life to neutralize the strongly oxidizing environment present inside our body. The most interesting point about free radical caused cell injury is that we can combat against this physiological pathway, by doing some modifications in our food habits. Generally antioxidants mainly from fruits and vegetables are regarded as a richest reservoir of natural antioxidant compounds [6-10]. in vitro Evaluation of Leaves and Fruits of Elaeagnus latifolia L. for Antioxidant and Antimicrobial Activities

Study of the Effect of Dillenia indica Fruit Mucilage on the Properties of Metformin Hydrochloride Loaded Spray Dried Microspheres.

Natural materials are preferred over synthetic counterparts because of their biodegradable and biocompatible nature. The present work was proposed to utilize mucilage from natural source for the development of controlled release formulation of metformin hydrochloride. Natural mucilaginous substance extracted from Dillenia indica L. (DI) fruit was used in fabricating controlled release microspheres. The microspheres were prepared by spray drying method under different formulation parameters. The prepared microspheres were studied for particle size, drug excipient compatibility, particle shape and surface morphologies, drug entrapment efficiency, mucoadhesivity, and in vitro drug release properties. The prepared microspheres exhibited mucoadhesive properties and demonstrated controlled release of metformin hydrochloride. The study reveals that the natural materials can be used for formulation of controlled release microspheres and would provide ample opportunities for further study.