NISCAIR Online Periodicals Repository Collection: IJEB Vol.50(11) [November 2012]

Cloning and expression of a small heat and salt tolerant protein (Hsp22) from Chaetomium globosum

Title: Cloning and expression of a small heat and salt tolerant protein (Hsp22) from Chaetomium globosum

Authors: Aggarwal, Rashmi; Gupta, Sangeeta; Sharma, Sapna; Banerjee, Sagar; Singh, Priyanka

Abstract: The present study reports molecular characterization of small heat shock protein gene in Indian isolates of Chaetomium globosum, C. perlucidum, C. reflexum, C. cochlioides and C. cupreum. Six isolates of C. globosum and other species showed a band of 630bp using specific primers. Amplified cDNA product of C. globosum (Cg 1) cloned and sequenced showed 603bp open reading frame encoding 200 amino-acids. The protein sequence had a molecular mass of 22 kDa and was therefore, named Hsp22. BlastX analysis revealed that the gene codes for a protein homologous to previously characterized Hsp22.4 gene from C. globosum (AAR36902.1, XP 001229241.1) and shared 95% identity in amino acid sequence. It also showed varying degree of similarities with small Hsp protein from Neurospora spp. (60%), Myceliophthora sp. (59%), Glomerella sp. (50%), Hypocrea sp. (52%), and Fusarium spp. (51%). This gene was further cloned into pET28a (+) and transformed E. coli BL21 cells were induced by IPTG, and the expressed protein of 30 kDa was analyzed by SDS-PAGE. The IPTG induced transformants displayed significantly greater resistance to NaCl and Na₂CO₃ stresses.

Page(s): 826-832

Enhanced rosmarinic acid production in cultured plants of two species of Mentha

Title: Enhanced rosmarinic acid production in cultured plants of two species of Mentha

Authors: Roy, Debleena; Mukhopadhyay, Sandip

Abstract: In the present investigation an attempt has been made to enhance rosmarinic acid level in plants, grown in vitro, of 2 species of Mentha in presence of 2 precursors in the nutrient media during culture. For in vitro culture establishment and shoot bud multiplication, MS basal media were used supplemented with different concentrations and combinations of different growth regulator like NAA (α-napthaleneacetic acid), BAP (6-benzylaminopurine). The medium containing NAA (0.25 mg/L) and BAP (2.5 mg/L) gave the highest potentiality of shoot formation (average 58.0 numbers of shoots) per explant for Mentha piperita L. and the medium containing BAP (2.0 mg/L) gave the highest potentiality of shoot (average 19.2 numbers of shoots) formation per explant for Mentha arvensis L. The complete plants were regenerated in above mentioned media after 8 weeks of subculture. For in vitro enhancement of rosmarinic acid production, the 2 precursors tyrosine (Tyr) and phenylalanine (Phe) were added in the nutrient media at different levels (0.5 mg/L to 15.0 mg/L). Tyrosine was found to be very effective for augmenting rosmarinic acid content in Mentha piperita L. It nearly increased the production up to 1.77 times. In case of Mentha arvensis L., phenylalanine significantly affected the production of rosmarinic acid and the production was nearly 2.03 times more than the control. No significant increase in biomass was observed after addition of these precursors indicating that the added amino acids acting as precursors for rosmarinic acid synthesis were readily utilized in producing rosmarinic acid without promoting growth. Total protein profile also revealed the presence of a specific band in polyacrylamide gel electrophoresis.

Page(s): 817-825

An efficient in vitro regeneration protocol for a natural dye yielding plant, Strobilanthes flaccidifolious Nees., from nodal explants

Title: An efficient in vitro regeneration protocol for a natural dye yielding plant, Strobilanthes flaccidifolious Nees., from nodal explants

Authors: Deb, Chitta Ranjan; Arenmongla, T

Abstract:   Adventitious shoot buds formation from axillary buds of nodal segments of S. flaccidifolious was achieved on MS medium containing sucrose (3%, w/v), and α-naphthalene acetic acid (NAA; 3 µM) and benzyl adenine (3 µM) in combination. The nodal segments were primed on ‘Growtak Sieve’ for 48 h on MS medium containing sucrose (2%), polyvinyl pyrollidone (200 mgL^-1) as antioxidant. About 80% of primed nodal segments responded positively and formed ~12 adventitious shoot buds per explants from explants collected during October-November months of every year. The shoot buds converted into plantlets on MS medium containing sucrose (3%) and kinetin (3 µM) where ~7 micro shoots developed per subculture after 8 weeks of culture. The regenerated micro shoots induced average 14 roots/ plant on medium containing NAA (3 µM). The regenerates were hardened for 6-7 weeks on medium with ½MS salt solution and sucrose (2%) under normal laboratory condition before transferring to potting mix. About 70% transplants survived after two months of transfer.

Page(s): 810-816

Virgin coconut oil improves hepatic lipid metabolism in rats–compared with copra oil, olive oil and sunflower oil

Title: Virgin coconut oil improves hepatic lipid metabolism in rats–compared with copra oil, olive oil and sunflower oil

Authors: Arunima, S; Rajamohan, T

Abstract: Effect of virgin coconut oil (VCO) on lipid levels and regulation of lipid metabolism compared with copra oil (CO), olive oil (OO), and sunflower oil (SFO) has been reported. Male Sprague-Dawley rats were fed different oils at 8% level for 45 days along with synthetic diet. Results showed that VCO feeding significantly lowered (P<0.05) levels of total cholesterol, LDL+ VLDL cholesterol, Apo B and triglycerides in serum and tissues compared to rats fed CO, OO and SFO, while HDL-cholesterol and Apo A1 were significantly (P<0.05) higher in serum of rats fed VCO than other groups. Hepatic lipogenesis was also down regulated in VCO fed rats, which was evident from the decreased activities of enzymes viz., HMG CoA reductase, glucose-6-phosphate dehydrogenase, isocitrate dehydrogenase and malic enzyme. In addition, VCO significantly (P<0.05) increased the activities of lipoprotein lipase, lecithin cholesterol acyl transferase and enhanced formation of bile acids. Results demonstrated hypolipidemic effect of VCO by regulating the synthesis and degradation of lipids.

Page(s): 802-809