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Fucose-containing sulfated polysaccharides, also termed "fucoidans", which are known to possess antioxidant, anticoagulant, anticancer, antiviral, and immunomodulating properties, are normally isolated from brown algae via various extraction techniques. In the present study, two methods (SC1 and SC2) for isolation of fucoidan from Sargassum cris- taefolium were compared, with regard to the extraction yields, antioxidant activity, and inhibition of growth of human colon cancer cells exhibited by the respective extracts. SC1 and SC2 differ in the number of extraction steps and concentration of ethanol used, as well as the obtained sulfated polysaccharide extracts, namely, crude fucoidan preparation (CFP) and purified fucoidan preparation (PFP), respectively. Thin layer chromatography, Fourier transform infrared analysis, and measurements of fucose and sulfate contents revealed that the extracts were fucoidan. There was a higher extraction yield for CFP, which contained less fucose and sulfate but more uronic acid, and had weaker antioxidant activity and inhibition of growth in human colon cancer cells. In contrast, there was a lower extraction yield for PFP, which contained more fucose and sulfate but less uronic acid, and had stronger antioxidant activity and inhibition of growth in human colon cancer cells. Thus, since the difference in bioactive activities between CFP and PFP was not remarkable, the high extraction yield of SC1 might be favored as a method in industrial usage for extracting fucoidan. [ABSTRACT FROM AUTHOR]

Histamine is the causative agent of scombroid poisoning, a foodborne chemical hazard. Histamine is degraded by the oxidative deamination activity of certain microorganisms. In this study, eight histamine-degrading bacteria isolated from salted fish products were identified as Rummeliibacillus stabekisii (1 isolate), Agrobacterium tumefaciens (1 isolate), Bacillus cereus (2 isolates), Bacillus polymyxa (1 isolate), Bacillus licheniformis (1 isolate), Bacillus amyloliquefaciens (1 isolate), and Bacillus subtilis (1 isolate). Among them, B. polymyxa exhibited the highest activity in degrading histamine than the other isolates. The ranges of temperature, pH, and salt concentration for growth and histamine degradation of B. poly- myxa were 25-37°C, pH 5-9, and 0.5-5% NaCl, respectively. B. polymyxa exhibited optimal growth and histamine-degrading activity at 30°C, pH 7, and 0.5% NaCl in histamine broth for 24 hours of incubation. The histamine-degrading isolate, B. polymyxa, might be used as a starter culture in inhibiting histamine accumulation during salted fish product fermentation. [ABSTRACT FROM AUTHOR]

It is important to develop rapid methods to detect the presence of histamine producers. In this study, the polymerase chain reaction (PCR) assay yielded a 367-bp DNA amplification fragment from histidine decarboxylase (hdc) of gram-positive bacteria using JV16HC/JV17HC primer, and 534-bp and 709-bp DNA amplification fragments from histidine decarboxylase of gram-negative bacteria using 106/107 and hdc-f/hdc-r primers, respectively. Seven gram-positive histamine-producing strains and 15 gram-negative histamine- producing strains isolated from Taiwanese foods successfully produced the PCR amplification products. The minimum levels of detection of Enterobacter aerogenes or Raoultella ornithinolytica after the PCR amplification using hdc-f/hdc-r and 106/107 primers were 105 and 106 CFU/mL in TSB broth, and 106and 107 CFU/g in marlin homogenates, respectively. The hdc amplification using hdc-f/hdc-r primer was detected 2 h earlier than the HPLC detection of histamine in TSBH broth or marlin homogenates inoculated E. aerogenes or R. ornithinolytica. However, the detection of hdc amplification using the 106/107 primer and that of histamine by HPLC occurred at the same sampling time. Therefore, the PCR method could be easily used to detect potential histamine-producing bacteria in foods. [ABSTRACT FROM AUTHOR]