|AUGUSTUS, GDPS - Virudhunagar Hindu Nadars' Senthikumara Nadar College (VHNSN)|
Submitted to: Biomass and Bioenergy
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/28/2011
Publication Date: 4/20/2011
Citation: Augustus, G.D.P.S., Seiler, G.J. 2011. Phytochemicals of selected plant species of the Apocynaceae and Asclepiadaceae from Western Ghats, Tamil Nadu, India. Biomass and Bioenergy. 35:3012-3017.
Interpretive Summary: There is a renewed interest in evaluating plant species as alternative sources of non-conventional energy since the fossil fuels are quickly being depleted. Solar energy is converted into a wide variety of by-products by green plants that can be competitive with synthetic petrochemicals, especially plants containing secondary metabolites such as oils and hydrocarbons that are attractive alternate energy and chemical sources. Utilization of whole-plant oils as an alternative source of conventional oils and major industrial feed stocks is gaining greater importance throughout the world. Many plants from various parts of the world remain to be evaluated for their potential as possible energy producing plants. There has not been a systematic study of plant species of India listing their potential as alternative sources of energy, hydrocarbon, and other phytochemicals. Therefore, there is a need to screen and identify potential species from the Western Ghats. The objective of this study was to evaluate seven latex producing species for extractable oil, polyphenol, hydrocarbon, protein, ash, heat content, and carbohydrates. The highest protein content was observed in Caralluma attenuata with 6.6%. Plant samples of Aganosma cymosa yielded 10.3% oil. The highest polyphenol content was observed in Carissa carandas with 7.7%. The species in the milkweed family had the highest hydrocarbon content. The gross heat and calorific value of the oil from all species was greater than that of anthracite coal. Several new species were identified with potentially useful compounds and are potential candidates for further study as energy sources. The potential exists for growing these alternate crops in areas of underutilized lands, subsequently stimulating industrial and economic growth.
Technical Abstract: A concern about the declining supply of petroleum products has led to a renewed interest in evaluating plant species as potential alternate sources of energy. Five species of the Apocynaceae and three species of the Asclepiadaceae from the Western Ghats were evaluated as alternative sources of energy, oil, polyphenol, and phytochemicals. The highest protein content was observed in Caralluma attenuata with 6.6%. Plant samples of Aganosma cymosa yielded 10.3% oil. The highest polyphenol content was observed in Carissa carandas with 7.7%. Species of the Asclepiadaceae exhibited the highest quantity of hydrocarbon viz Sarcostemma brevistigma (3.6%), Caralluma attenuata (3.4%), and Tylophora asthmatica (2.7%). Carbohydrate content was high in Sarcostemma brevistigma with 6.9%. A whole plant gross calorific value of 16.5 MJkg-1 for Nerium odorum (white flower variety) was the highest value observed. The highest gross calorific value observed in the oil fraction was from Caralluma attenuata with 33.4 MJkg-1. The hydrocarbon fraction of Tylophora asthmatica exhibited the highest gross calorific value of 39.2 MJkg-1. The hydrocarbon fractions were further analyzed using NMR to determine the type of isoprene present. Fatty acid compositions of oil samples were also analyzed. All the species except N. odorum (white flower variety) contained higher quantities of saturated fatty acids than unsaturated fatty acids.