Journal of Environmental Biology

Permanent URI for this collection

https://imsear.searo.who.int/handle/123456789/113129

Browse

Browsing Journal of Environmental Biology by Subject "16S rRNA"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    Fatty acid profiles of Antarctic cyanobacteria Leptolyngbya
    (Triveni Enterprises, 2020-07) Abidin, Z.A. Zainal; Zainuddin, Z.; Mastrai, S.F.Q. Wan; Merican, F.M. Mohd Sidik; Convey, P.
    Aim: Antarctic cyanobacteria may represent a potential resource of new and unique compounds with interesting capabilities. Profiling of fatty acids in Antarctic cyanobacteria can provide an overview of potential fatty acids present in them, that can be utilised in future applicationsMethodology: In total, 4 cyanobacteria previously isolated from Antarctic polar ice was used in this study. Molecular identification using 16S rRNA gene was used to ascertain their identities as Leptolyngbya spp. and their fatty acid profiles were determined using GCMS. Results: Morphologically, these cyanobacteria were found similar to Leptolyngbya sp. Analysis of 16S rRNA gene sequences amplified further confirmed their identity and were designated as Leptolyngbya sp. A, B, D and E. Following fatty acid analysis using GCMS, it was determined that unsaturated fatty acids predominated the fatty acid profiles for Leptolyngbya sp. A, B and D, while saturated fatty acid was found dominant in Leptolyngbya sp. E. Leptolyngbya sp. D contained almost 100% of linoleic acid, whilst Leptolyngbya sp. A and Leptolyngbya sp. B contained 59.35% and 83.33% of linoleic acid, respectively. Besides linoleic acid, palmitoleic acid (18.45%), oleic acid (19.45%) and lauric acid (2.74%) were also present in Leptolyngbya sp. A. As for Leptolyngbya sp. B, other than linoleic acid, only oleic acid (16.67%) was detected. Interpretation: Findings from this study demonstrate that the Antarctic Leptolyngbya spp. A, B and D identified in this study possess high content of unsaturated fatty acids, while only saturated fatty acid was present in Leptolyngbya sp. E. Fatty acid profiles revealed the potential of these Antarctic Leptolyngbya species to be further exploited for other applications.
  • Thumbnail Image
    Item
    Identification and characterization of bacteria isolated under selective pressure of volatile organic compounds.
    (2009-01) Civilini, Marcello
    Several bacterial strains tolerant to volatile organic compounds (VOCs) were isolated from the air emissions of a typical industrial wood painting plant. Four strains that grew vigorously on a mineral salt basal medium and VOC-saturated atmosphere were identified using BIOLOG and fatty acids analysis. A 16S rDNA sequence comparison was also performed on three of the four strains. Their phylogenetic positions were respectively: MC8M6 of the genus Arthrobacter, MCEP3 of the genus Microbacterium, MCEPFL2 of the genus Rhodococcus. The fourth strain, C14, was identified as Pseudomonas aeruginosa. All the four strains showed multiple carbon sources among toluene, butyl acetate, ethoxy propyl acetate, isobutyl alcohol, ethyl acetate, diaceton alcohol, methyl ethyl ketone, methyl isobutyl ketone. By identifying a particular strain, an evaluation of its risk group can be made by comparing it to each strain type within important world-wide culture collections. This is the first step required to implement correct procedures using the strains and in implementing the appropriate biosafety containment in large scale applications.
  • No Thumbnail Available
    Item
    Identification of bacterial endosymbionts in rice weevil, Sitophilus oryzae Linnaeus (Coleoptera: Curculionidae) populations of North India
    (Triveni Enterprises, 2024-01) Kaundal, P.; Padwal, K.G.; Premkumari, S.; Chakravarty, S.; Srivastava, C.P.
    Aim: The present study was undertaken to screen the most commonly occurring endosymbionts in S. oryzae populations from varied geographical regions of North India. Methodology: The six most common endosymbionts (Wolbachia, Arsenophonus, Spiroplasma, Rickettsia, Cardinium and Hamiltonella) were screened in 15 different populations of S. oryzae, representing five different agro-climatic zones of India. For this, the samples of S. oryzae were collected and identified using taxonomic keys and through PCR amplification of the COI gene followed by Sanger sequencing and comparison of obtained sequences with the NCBI database. Thereafter, the screening of endosymbionts was performed using 16S rRNA gene-specific primers for the respective endosymbionts. Results: The results showed the presence of Wolbachia and Spiroplasma in all 15 populations with infection rates of 100 and 85 per cent, respectively. Arsenophonus was detected in only 12 populations with 60 per cent infection rate. Concurrent infections of Wolbachia, Arsenophonus and Spiroplasma within the same individuals of S. oryzae were also detected. However, no infections of Cardinium, Rickettsia and Hamiltonella were found. Interpretation: Thus, it can be inferred that Wolbachia, Spiroplasma and Arsenophonus are the most common endosymbionts which can be exploited for the development of better management strategies against S. oryzae.