Grazing characteristics of musty-odor-compound-producing Phormidium tenue by a microflagellate, Monas guttula

The musty odor compound geosmin was electrochemically detected by using Pt nanoparticle (PtNP)-embedded nanocarbon (Pt–C) films formed with unbalanced magnetron (UBM) co-sputtering.

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Removal of Musty Odor Compound in Drinking Water by Biological Filter

Water Science & Technology ◽

10.2166/wst.1992.0066 ◽

1992 ◽

Vol 25 (2) ◽

pp. 307-314 ◽

Cited By ~ 20

Author(s):

K. Egashira ◽

K. Ito ◽

Y. Yoshiy

Keyword(s):

Drinking Water ◽

Water Temperature ◽

Granular Media ◽

Packed Column ◽

Oxygen Demand ◽

Biological Filtration ◽

Biological Filter ◽

Drinking Water Resources ◽

Musty Odor ◽

Musty Odor Compound

In order to remove the musty odor compound 2-methyl isoborneol (MIB) from drinking water resources at Lake Biwa, a pilot plant of a biological filtration was installed and operated. In this study, the effects of water temperature, pH and initial concentration of MIB on the MIB degradation potential of the ceramic media packed column in the biological filter were studied. Microorganisms on the surface of the granular media were observed under the scanning electron microscope (SEM). Bacteria which were responsible for the degradation were isolated, studied and identified. From this experiment, the extent of the effect of water temperature on the degradation potential was found to be similar to that on the biochemical oxygen demand (BOD) removal activity by an activated sludge. The optimum pH for the degradation potential was seen to be between 7 and 9. The MIB degradation reaction was seen to be almost a first order reaction. On the surface of the washed granular media, coccoid and rod-shaped bacteria were observed. Eleven out of 34 bacteria isolated from the washed media were judged as biodegraders. Some characteristics of 7 Gram negative biodegraders were studied and two strains of Pseudomonasaeruginosa,one strain of Flavobacteriummultivorum, one strain of Pseudomonas sp. and one strain of Flavobacterium sp. were identified.

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The Relationship between Concentration and Sensory Properties of 2-Methylisoborneol and Geosmin in Drinking Water

Water Science & Technology ◽

10.2166/wst.1988.0218 ◽

1988 ◽

Vol 20 (8-9) ◽

pp. 11-17 ◽

Cited By ~ 4

Author(s):

T. Ito ◽

T. Okumura ◽

M. Yamamoto

Keyword(s):

Drinking Water ◽

Water Temperature ◽

Forced Choice ◽

Residual Chlorine ◽

Mixing Ratio ◽

Consumer Panel ◽

Triangle Method ◽

Musty Odor ◽

The Relationship ◽

Mixed Samples

The study of the relations between the senses of smell and taste and odorant concentration is important for the solution of odor problems. The threshold concentrations of odor and taste (TOC, TTC) of 2-methylisoborneol (MIB) and geosmin were measured by the non-forced choice triangle method using 12-20 panelists. Both TOC and TTC were found to be functions of water temperature and the concentration of residual chlorine. The TOC and TTC of mixed samples were rather lower than the concentrations calculated from the mixing ratio. The sensitivities of the consumer panel and the number of musty odor complaints from consumers are related to MIB or geosmin concentration. The ratio of the number of complaints to MIB (or geosmin) concentration decreased after maximum complaint, but the sensitivity of the consumer panel remained the same.

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The relationship between musty-odor-causing organisms and water quality in Lake Biwa

Water Science & Technology ◽

10.2166/wst.1995.0426 ◽

1995 ◽

Vol 31 (11) ◽

pp. 153-158 ◽

Cited By ~ 3

Author(s):

M. Kajino ◽

K. Sakamoto

Keyword(s):

Water Quality ◽

Data Analysis ◽

Green Algae ◽

Analytical Methods ◽

Lake Biwa ◽

Blue Green Algae ◽

Odor Compounds ◽

Musty Odor ◽

The Relationship

Musty odor has occurred annually in Lake Biwa since 1969. Osaka municipal waterworks, which is located downstream of Lake Biwa, has made many efforts to treat musty-odor compounds produced in Lake Biwa from spring through autumn. With the development of analytical methods for the determination of musty-odor compounds, we have been able to confirm that planktonic blue-green algae are the major causes of the musty-odor occurrences. The relationship between the growth of blue-green algae and the water quality was not so apparent. However, through our data analysis focusing on the relationship between musty-odor occurrences due to Phormidium tenue or Oscillatoria tenuis and some nutrients in Lake Biwa, we found that the concentration of nitrate in water may be an important parameter for the estimation of growth of the algae and the musty-odor behavior.

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PTSA (pressure and thermal swing adsorption) method to remove trihalomethanes from drinking water

Water Science & Technology ◽

10.2166/wst.1997.0283 ◽

1997 ◽

Vol 35 (7) ◽

pp. 243-250 ◽

Cited By ~ 1

Author(s):

Shigekazu Nakano ◽

Tomoko Fukuhara ◽

Masami Hiasa

Keyword(s):

Drinking Water ◽

Residual Chlorine ◽

Remarkable Difference ◽

Adsorption Method ◽

Heating And Cooling ◽

Point Of Use ◽

Thermal Swing Adsorption ◽

Long Time ◽

Musty Odor ◽

Vacuum Heating

It has been widely recognized that trihalomethanes (THMs) in drinking water pose a risk to human health. THMs can be removed to a certain extent by the conventional point-of-use (POU) unit which is composed of activated carbon (AC) and microfilter. But it's life on THMs is relatively shorter than on residual chlorine or musty odor. To extent the life of AC adsorber, pressure and thermal swing adsorption (PTSA) was applied by preferential regeneration of chloroform. PTSA was effective to remove THMs, especially chloroform. Adsorption isotherms of chloroform at 25 and 70°C showed a remarkable difference so that thermal swing was considered effective. Chloroform was also desorbed by reducing pressure. By vacuum heating at 70°C, chloroform was almost desorbed from AC and reversible adsorption was considered possible. A prototype of POU unit with PTSA was proposed. Regeneration mode would consist of dewatering, vacuum heating and cooling (backwashing). The unit was maintained in bacteriostatic condition and could be used for a long time without changing an AC cartridge.

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Impact of diuron applications to commercial catfish ponds on musty‐odor cyanobacteria, musty off‐flavor compound concentrations, and catfish fillet flavor quality

North American Journal of Aquaculture ◽

10.1002/naaq.10225 ◽

2021 ◽

Author(s):

Kevin K. Schrader

Keyword(s):

Flavor Quality ◽

Flavor Compound ◽

Musty Odor ◽

Catfish Ponds

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Application of post-column reaction GC for accurate and direct determination of musty odor substances in standard solution

Accreditation and Quality Assurance ◽

10.1007/s00769-018-1338-4 ◽

2018 ◽

Vol 23 (5) ◽

pp. 297-302 ◽

Cited By ~ 2

Author(s):

Yuko Kitamaki ◽

Naoki Saito ◽

Masahiko Numata ◽

Toshihide Ihara

Keyword(s):

Direct Determination ◽

Musty Odor ◽

Standard Solution

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Potato-Like Odor of Retail Beef Cuts Associated with Species of Pseudomonas

Journal of Food Protection ◽

10.4315/0362-028x-49.4.272 ◽

1986 ◽

Vol 49 (4) ◽

pp. 272-273 ◽

Cited By ~ 6

Author(s):

R. L. DAISE ◽

E. A. ZOTTOLA ◽

R. J. EPLEY

Keyword(s):

Coliform Bacteria ◽

Plate Count ◽

Aerobic Bacteria ◽

Gram Negative ◽

Consumer Complaints ◽

Psychrotrophic Bacteria ◽

Plate Count Agar ◽

Litmus Milk ◽

Musty Odor ◽

Retail Cuts

Retail cuts of beef and hamburger packages from a North Dakota meat processor were examined due to consumer complaints of a strong potato-like or musty odor associated with the meat. Examination for total numbers of aerobic bacteria on plate count agar and for gram-negative psychrotrophic bacteria on crystal violet tetrazolium agar revealed numbers in excess of 108 CFU/g. Numbers of coliform bacteria on violet red bile agar were in excess of 106 CFU/g. Gram-negative rods were isolated and identified. The isolates were characterized by a positive catalase reaction, oxidase production, an oxidative O/F reaction, nonutilization of lactose, liquefication of nutrient gelatin, slight motility, production of acid in litmus milk with decoloration and clotting, nonproduction of indole, and nonreduction of nitrate. The isolate was tentatively identified as a Pseudomonas of undetermined species, probably a variant of either Pseudomonas taetrolens or Pseudomonas perolens.

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Iron Forms That Influence the Growth and Musty Odor Production of Selected Cyanobacteria

Water Science & Technology ◽

10.2166/wst.1992.0054 ◽

1992 ◽

Vol 25 (2) ◽

pp. 207-216 ◽

Cited By ~ 3

Author(s):

S. Nakashima ◽

M. Yagi

Keyword(s):

Iron Oxides ◽

Ferric Hydroxide ◽

Chelating Agent ◽

Iron Chelator ◽

The Other ◽

Colloidal Iron ◽

Desferrioxamine B ◽

Musty Odor ◽

Iron Forms ◽

Odor Production

In order to clarify the mechanism of growth of musty-odor producing cyanobacteria, the effects of iron forms on growth and musty-odor production in four species of cyanobacteria, Oscillatoriabrevis, Anabaenamacrospora, Phormidiumtenue and Oscillatoriatenuis were studied using laboratory batch cultures. The former two cyanobacteria produce geosmin and the latter two produce 2-methylisoborneol (MIB). The growth of A. macrospora, P. tenue and O. tenuis was suppressed in the EDTA (chelating agent)-free CT medium. However, O. brevis grew well and produced geosmin in this medium as well as in the presence of EDTA. Thus, O. brevis showed an ability to utilize colloidal iron and even iron oxides for its growth. This suggests that O. brevis would be expected to produce a specific high affinity iron chelator (siderophore) in the chelator-free medium. In the presence of bathophenanthroline disulfonate (BPDS), a strong Fe(II) chelating agent, O. brevis and P. tenue were able to grow, but A. macrospora and O.tenuis did not. Furthermore, O.brevis was capable of growing in the medium containing a microbial siderophore, desferrioxamine B(DESF), instead of EDTA, but the other three cyanobacteria did not grow. These results show that O. brevis has an excellent ability to utilize a variety of iron forms including Fe (II I)-EDTA, Fe (II)-BPDS,.Fe (III)-DESF chelates, colloidal ferric hydroxide and more thermodynamically stable crystalline iron oxides (Fe2O3 and Fe3O4) in comparison with the other three musty-odor producing cyanobacteria isolated from Lake Biwa.

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