NISCAIR Online Periodicals Repository Collection: IJBT Vol.09(4) [October 2010]

Cryopreservation of excised embryonic axes of Nothapodytes nimmoniana (Graham) Mebberly—A vulnerable medicinal tree species of the Western Ghats

Tue, 28 Sep 2010 22:58:59 GMT

Title: Cryopreservation of excised embryonic axes of Nothapodytes nimmoniana (Graham) Mebberly—A vulnerable medicinal tree species of the Western Ghats

Authors: Radha, R K; Decruse, S William; Krishnan, P N

Abstract: Desiccation sensitivity and freezing tolerance of excised embryonic axes from the seeds of Nothapodytes nimmoniana (Graham) Mebberly and their cryopreservation were examined. Zygotic embryos with cotyledons excised from fully ripened fruits possessed 55.7% moisture content (MC) and 86.67% of them germinated in Murashige and Skoog (MS) medium devoid of plant growth regulators (PGR). Dehydration under laminar airflow for 120 min reduced the MC of the embryos to 19.6% and germination to 68%. Subsequent reduction in MC to 15.4, 14.2 and 12.1% also reduced the germination. Embryos dehydrated for 120 min after 1-wk-storage in Liquid nitrogen (LN) showed 60% germination, which was the optimum condition obtained in the study. The LN treated embryos developed into healthy seedlings after 30-60 d of inoculation in MS basal medium similar to desiccated control. Prolonged desiccation damaged the plumule where only root formation was observed. The study reveals the possibility of long term ex situ conservation of N. nimmoniana, which produces large and intermediate type of seeds, through zygotic embryo cryopreservation.

Page(s): 435-437

Sequence analysis and homology based modeling to assess structure-function relationship of Pediocin CP2 of Pediococcus acidilactici MTCC 5101

Tue, 28 Sep 2010 22:58:59 GMT

Title: Sequence analysis and homology based modeling to assess structure-function relationship of Pediocin CP2 of Pediococcus acidilactici MTCC 5101

Authors: Balgir, Praveen Pal; Bhatia, Puja; Kaur, Baljinder

Abstract: A plasmid encoded pediocin CP2 sequence was analyzed using various bioinformatics tools. Multiple sequence alignment of pediocin CP2 depicted 100% sequence similarity with pediocin PA-1/pediocin AcH. Since no detailed 3D structure or structure-function analysis is available in literature, the 3D structure of pediocin CP2 was obtained based on the known structure of homologous sakacin P. It was analyzed and deduced that YGNGV motif contained in N-terminal β-sheet in pediocin CP2 makes it antilisterial. It was followed by a well defined central amphiphillic α-helix (residues 20-30), and this in turn was followed by the C-terminal tail (residues 31-44), which folds back onto the central α-helix, thereby creating a hairpin-like structure. This hairpin-like structure was stabilized by the presence of a second disulphide bridge in pediocin CP2 (because of extra cysteine residue C₄₄) which was absent in the reference peptide sakacin P. High thermostability and broad antimicrobial range of the pediocin CP2 in comparison to sakacin P is attributed to the presence of this second disulphide bond that can further be verified by experimentation.

Page(s): 431-434

Effects of inoculation on production of anticancer drug-cordycepin in surface liquid culture using Cordyceps militaris mutant: A minor factor may greatly affect the result

Tue, 28 Sep 2010 22:58:59 GMT

Title: Effects of inoculation on production of anticancer drug-cordycepin in surface liquid culture using Cordyceps militaris mutant: A minor factor may greatly affect the result

Authors: Das, Shonkor Kumar; Masuda, Mina; Hatashita, Masanori; Sakurai, Akihiko; Sakakibara, Mikio

Abstract: To explore the effects of inoculation on the production of anticancer drug cordycepin in surface liquid culture using Cordyceps militaris mutant, several inoculants [single (control), double and triple] were used in the present experiment. HPLC analysis for cordycepin concentration, mutarotase-glucose oxidase method using Glucose CII test for glucose concentration, and dry cell mycelia were measured. Analysis showed that the cordycepin productions in control, double and triple inoculants were 5.05, 6.11 and 5.61 g L^-1, respectively. It was highest in double inoculants and was 21% and 8.91% higher than those of the control and triple inoculants, respectively. Similarly, the cordycepin production in triple inoculants also superseded the control by 11.09%, but was lower than that of the doubleinoculants. Regarding glucose consumption, it was revealed that the consumption in triple inoculants was the fastest, while in double inoculants it was faster than the control. The dry mycelia weights showed a descending trend as 3.27, 3.20 and 3.17 g for triple, double and single inoculants, respectively, indicating a positive correlation between the production of cordycepin and the dry mycelia weight, but not linear. The number of inoculants used greatly affected the production of cordycepin and also positively correlated to the dry mycelia weight.

Page(s): 427-430

Standardization of DNA isolation and PCR parameters in Garcinia spp. for RAPD analysis

Tue, 28 Sep 2010 22:58:59 GMT

Title: Standardization of DNA isolation and PCR parameters in Garcinia spp. for RAPD analysis

Authors: Asish, G R; Parthasarathy, Utpala; Nithya, N G

Abstract: Doyle and Doyle protocol with a little modification was used for the isolation of DNA from leaves and fruit rind of Garcinia spp. In case of leaves and dry fruit rind, the best DNA isolation was possible with 4% CTAB (100 mM Tris, 30 mM EDTA & 1.4 M NaCl), followed by 1.5% PVP and 0.3% mercaptoethanol. In case of fresh fruit rind, the DNA was best isolated with 2% CTAB (100 mM Tris, 30 mM EDTA & 1.4 M NaCl). PCR parameters were optimized using random RAPD primers. Other parameters included the DNA concentration at 50 ng/reaction, annealing temperature of 43°C, 2.5 mM dNTP in presence of 1 U Taq DNA polymerase and 2.0 mM MgCl₂. The protocol will be of great help to study the genetic diversity of Garcinia germplasms.

Page(s): 424-426