PARTICULATE ORQANIC MATTER I N SEA WATER
33
Strickland and Solozano (1966) had failed to find carbohydrates containing phosphorus. In the case of deep water particulate matter, they
reported that large quantities of carbon remained unaccounted for
after correcting for carbohydrate determined by direct analysis and
subtracting likely values for protein carbon. They suggested that
there must be “ either a high proportion of non-nitrogenous material
or an inert organic residuum with a very high carbon to nitrogen ratio.”
This of course is very different from the situation that Parsons and
Strickland (1962) had found earlier in offshore waters of the North
Pacific.
Hobson (1967) determined carbohydrates in particulate matter
collected at his three stations in the North Pacific. Deep water values
for carbohydrate-carbon in his various cruises averaged 13-28% of
total carbon. These are slightly lower than the average obtained by
Parsons and Strickland.
Handa (1968), whose studies of C : N ratios in the waters off Japan
have already been reported, was particularly concerned with the biochemical characterization of the carbohydrate fraction and has provided the most detailed information on that subject which is thus far
available. His paper also contains incidental information on the ratio
of amino N to total organic N, which is summarized briefly in passing
by saying that amino N was more than 85% of the total and tended t o
increase slightly and irragularly with depth.
The total particulate carbohydrate carbon was of the order of
20 pg C/litre in surface waters and 4-6 pg between 100 and 1 000 m.
The most important monosaccharide components were glucose,
galactose, mannose, xylose, and glucuronic acid. D-glucose was the
most important one in the immediate surface layer, decreasing gradually
in the upper 200 m. Otherwise there was little change in relative
proportions with depth.
One hundred litre samples were taken a t depths of 20, 500 and
700 m for detailed analysis. Soluble carbohydrate was removed from
the particulate matter with a hot aqueous solution followed by ethanol
and acetone treatment for further fractionation. The remaining particulate matter was treated with Schweizer’s reagent to extract polysaccharides. The material so obtained was examined by standard
methods to determine the monosaccharide composition and the
degree of polymerization that was involved.
Two of the soluble fractions gave only D-glucose upon acid hydrolysis. One of these was specified as containing D-glucose and two oligosaccharides ; the other was D-glucan. A third fraction contained
galactose, glucose, mannose and xylose. The water insoluble fraction
33
Strickland and Solozano (1966) had failed to find carbohydrates containing phosphorus. In the case of deep water particulate matter, they
reported that large quantities of carbon remained unaccounted for
after correcting for carbohydrate determined by direct analysis and
subtracting likely values for protein carbon. They suggested that
there must be “ either a high proportion of non-nitrogenous material
or an inert organic residuum with a very high carbon to nitrogen ratio.”
This of course is very different from the situation that Parsons and
Strickland (1962) had found earlier in offshore waters of the North
Pacific.
Hobson (1967) determined carbohydrates in particulate matter
collected at his three stations in the North Pacific. Deep water values
for carbohydrate-carbon in his various cruises averaged 13-28% of
total carbon. These are slightly lower than the average obtained by
Parsons and Strickland.
Handa (1968), whose studies of C : N ratios in the waters off Japan
have already been reported, was particularly concerned with the biochemical characterization of the carbohydrate fraction and has provided the most detailed information on that subject which is thus far
available. His paper also contains incidental information on the ratio
of amino N to total organic N, which is summarized briefly in passing
by saying that amino N was more than 85% of the total and tended t o
increase slightly and irragularly with depth.
The total particulate carbohydrate carbon was of the order of
20 pg C/litre in surface waters and 4-6 pg between 100 and 1 000 m.
The most important monosaccharide components were glucose,
galactose, mannose, xylose, and glucuronic acid. D-glucose was the
most important one in the immediate surface layer, decreasing gradually
in the upper 200 m. Otherwise there was little change in relative
proportions with depth.
One hundred litre samples were taken a t depths of 20, 500 and
700 m for detailed analysis. Soluble carbohydrate was removed from
the particulate matter with a hot aqueous solution followed by ethanol
and acetone treatment for further fractionation. The remaining particulate matter was treated with Schweizer’s reagent to extract polysaccharides. The material so obtained was examined by standard
methods to determine the monosaccharide composition and the
degree of polymerization that was involved.
Two of the soluble fractions gave only D-glucose upon acid hydrolysis. One of these was specified as containing D-glucose and two oligosaccharides ; the other was D-glucan. A third fraction contained
galactose, glucose, mannose and xylose. The water insoluble fraction