Genomic DNA extraction from sapwood of Pinus roxburghii for polymerase chain reaction studies

A method for extraction of genomic DNA from sapwood tissues of mature tall trees of Pinus roxburghii, where collection of needle tissues is extremely difficult has been standardized. The extracted DNA was comparable to that obtained from the needle tissue in terms of yield and purity. The yield of extracted DNA ranged from 6.98 to 19.668 μg / 100 mg tissue and A260 / A280 ratio ranged from 1.70 to 1.87. The polymerase chain reaction (PCR) amplification of the DNA extracted from sapwood tissue using random amplification of polymorphic DNA (RAPD), inter simple sequence repeat (ISSR) and simple sequence repeat (SSR) markers was similar to that of DNA extracted from the needle tissues.Keywords: Pinus roxburghii, DNA extraction, sapwood, random amplification of polymorphic DNA (RAPD), inter simple sequence repeat (ISSR), simple sequence repeat (SSR)African Journal of Biotechnology Vol. 12(15), pp. 1732-173

Molecular investigation between four Himalayan pines of India through random amplified polymorphic DNA markers

Studies were undertaken to identify genetic relationship in four different species of Pinus L. through randomly amplified polymorphic DNA (RAPD) markers. A total of 500 DNA fragments ranging from 234 to 1353 bp were amplified using 5 selected primers. The number of amplification products produced by a primer ranged from as low as 4 to a maximum of 13, with an average of 8 bands per primer. The cluster analysis revealed one major cluster and one outlier. In the major cluster, Pinus roxburghii from Malithi, Pinus wallichiana from Malithi, P. wallichiana from Taradevi H.P, Pinus kesiya from Taradevi H.P, Pinus gerardiana from Chamba and P. roxburghii from Chamba falls into subcluster 1 and P. kesiya from Jubbal (east) and P. kesiya from Jubbal (west) falls into subcluster 2. The similarity coefficient value varied from 0.54 to 0.88. The highest similarity coefficient (0.88) was detected between samples collected from P. wallichiana (Malithi) and P. roxburghii (Malithi) as well as between P. roxburghii (Malithi) & P. wallichiana (Taradevi, H.P) and the lowest (0.54) was detected between the P. gerardiana (Raspa) and P. kesiya (South Vietnam). The level of polymorphism in our study was not so much which showed that samples used for the analysis could have close relationship.Key words: Randomly amplified polymorphic DNA (RAPD), similarity coefficient, polymorphism, Pinus, primer

Thermochemical and structural changes in Jatropha curcas seed cake during torrefaction for its use as coal co-firing feedstock

Jatropha curcas seed cake is a viable feedstock for co-firing with coal as it has the advantages of being renewable, carbon-neutral and sourced from a versatile plant. Torrefaction, a mild pyrolysis treatment by heating in a N2 atmosphere, was investigated as a technique to improve the thermochemical properties of the biomass, primarily the HHV (higher heating value). The temperature and holding time were varied in the ranges of 200–300 °C and 0–60 min, respectively, to form a 5-level full-factorial experimental matrix. An optimum envelope of torrefaction parameters was identified in the range of 280 °C to >45 min at 220–250 °C under a heating rate of 10 °C/min. This results in an enhancement of the HHV from 24 MJ/kg to more than 27 MJ/kg, which is within the range of coal, while maintaining an energy yield higher than 90%. The relationships between the HHV and the proximate fixed carbon content as well as the elemental CHO content were also investigated. Through 13C NMR (nuclear magnetic resonance) spectroscopy, hemicellulose was determined as the most volatile component, undergoing decomposition before 250 °C while cellulose only degraded fully in the 250–300 °C range and lignin decomposition spanned from 200 °C to beyond 300 °C