Rapid Counting of Liquid-Borne Microorganisms by Light Scattering Spectrometry

Details

• Personal Author:
  Gorny R ; Mainelis G ; Reponen T ; Willeke K
• Description:
  Fast and sensitive techniques are needed to determine microorganism presence in liquid samples. In this research, the feasibility of using light scattering spectrometry for enumerating the biological particles in liquid samples was investigated. A particle size spectrometer was used to count six commonly found microbial species suspended in liquid with and without microbiological stains applied: Pseudomonas fluorescens, Micrococcus spp. vegetative cells and Bacillus subtilis var. niger endospores were stained with Acridine Orange and Crystal Violet, while Cladosporium cladosporioides, Penicillium melinii and Aspergillus versicolor fungi were stained with Acridine Orange and Lactophenol Cotton Blue. The counts obtained with the spectrometer were compared with those obtained with a phase-contrast microscope. It was found that the spectrometer counted about 32 % of non-stained B. subtilis endospores and this percentage increased to almost 90 % for stained endospores. Among the investigated species of fungi, the counting efficiency of P. melinii was the only one significantly affected by the application of the stain Lactophenol Cotton Blue: the fraction of counted fungal spores increased from 64 % (non-stained spores) to about 100 % (stained spores). The observed difference in counting efficiency may serve as a basis for differentiating biological from non-biological particles in liquid samples. [Description provided by NIOSH]
• Subjects:
  Biological Products Fungi Fungicide, Industrial Microbiology Occupational Health Safety
• Keywords:
  Bacteria Biological-agents Fungicides Microorganisms Sampling
• ISSN:
  1232-1966
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article
• Place as Subject:
  New Jersey ; Ohio ; OSHA Region 2 ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH)
• Topic:
  Workplace Safety & Health
• Location:
  North America
• Pages in Document:
  141-148
• Volume:
  12
• Issue:
  1
• NIOSHTIC Number:
  nn:20028866
• Citation:
  Ann Agric Environ Med 2005 Jan; 12(1):141-148
• Email:
  mainelis@envsci.rutgers.edu
• Federal Fiscal Year:
  2005
• NORA Priority Area:
  Research Tools and Approaches: Exposure Assessment Methods
• Performing Organization:
  University of Cincinnati
• Peer Reviewed:
  True
• Start Date:
  19970930
• Source Full Name:
  Annals of Agricultural and Environmental Medicine
• End Date:
  20030331
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:f7b2046747054ea0645a0f55eba40924d5cfe564aefcfe4da0715b10028095963b540408d97d1e06b922e73ca50259ed56ab2ab0f8b8532e9578b19d1a9182ed
• Download URL:
  https://stacks.cdc.gov/view/cdc/189962/cdc_189962_DS1.pdf
• File Type:
  [PDF - 133.00 KB ]