I
'
SEASONAL CHANGES IN THE
CONTENT OF NON-METALLIC
INORGANIC COMPONENTS IN
THE MARINE ALGA
MACROCYSTIS INTEGRIFOLIA
oy
J.N.C. Whyte and J.R. Englar
Industry, Technology and Inspection Directorate
Fisheries and Marine Service
Department of Fisheries and the Environment
6640 N.W. Marine Drive
Vancouver, British Columbia
V6T 1X2 Canada
-
February 1978
Fisheries and Marine Service
Technical Report No. 765
Fisheries and Marine Service
Technical Reports
Th ese report s co nt ain sc ientific and tec hni ca l informati on th at represe nt s an
important co ntributi on to ex isting knowl edge but which for so m e reaso n ma y no t
be ap propriat e for primary sc ient ific (i .e. Journ al) publicati on. T ec hni ca l Report s
are direc ted prim aril y towa rds a world wide audi ence and have an int ern ati onal
di stributi on. No res tri cti on is pl aced on subj ec t m att er and th e se ri es re n ec ts th e
br oad interes ts and poli cies o f th e Fi sheri es and Marin e Se r v ice, nam ely, fi sher ies
m anage m ent , tec hn ology ancl deve lop m ent , ocea n sc iences and aq uati c en vironm ent s releva nt to Ca nada.
T echnical Repo rt s m ay be cit ed as full publi ca ti ons. Th e cor rec t citati on
appears above th e abs trac t of eac h report. Eac h report will be abstrac ted in Aquatic
Sciences and Fisheries Abstracts and will be indexed annu all y in th e Ser vice's ind ex
to sc ientifi c and tec hni ca l publi ca ti ons.
Nu m bers 1-456 in thi s se ri es we re iss uecl as T ec hni ca l Repo rt s o f th e Fi sheri es
Resea rch Board of Ca nada. Numbers 457-7 14 we re iss ued as D epa rtm ent of th e
E n vironm ent , Fi sheri es ancl M arin e Service, R esea rch ancl D eve lopm ent Direc torat e T ec hni ca l Report s. Th e se ri es nam e was changecl w ith repo rt number 715.
Detail s on th e ava ilabilit y o f T ec hnic al Report s in hard co py m ay be ob tain ecl
from th e iss uin g es tabli shm ent indicated on th e front cove r.
Service des peches et des sciences de la mer
Rapports techniques
Ces rappo rt s co nti enn ent des rense ignem ent s scie ntifi ques et tec hniques qui
co nstitu ent un e co nt r ibuti on impo n ant e aux co nn aissa nces ac tu ell es mai s qui. pour
un e raiso n ou pour un e au tre, ne se mbl en t pas app rop ri es pour la publi ca ti on cl ans
un jou rn al sc ientifiqu e. II n 'y a aucun e res tri cti on quant au sujet , de fa it , la se ri e
ren ete la vas te ga mme c1es i nt erets et des politi ques du Se r vice c1es pech es et de la
m er, no t amm ent ges ti on des peches, tec hni ques et deve lopp em ent , sc iences
ocea niqu es et en vironn em ent s aqua ti ques, au Ca nada.
Les Rap port s tec hni ques peuve nt etre co nsieJe res co mm e des publi cat ions
co mpletes . L e titre exac t paraitra au haut du res um e de chaque rapp ort , qui se ra
publie da ns la rev ue Aquatic Sciences and Fisheries Abstracts et qui fi gurera dans
I' index annuel des publi ca ti ons sc ientifiques et t ec hniques du Se r vice.
L es num eros 1-456 de ce tt e se ri e ont ete publi es ,i titre de Rapp ort s tec hniqu es
de l'Office c1es rec herches sur les pec heri es du Canada . L es num eros 457 -700, it titre
de Rapport s tec hniques de la Direc ti on genera le ete la rec herche ct du
deve loppem ent , Se rv ice des peches et de la m er , mini ste re de l ' En vironn em ent. L e
nom c1e la se ri e a e l<~ m oclifi e partir c1u num ero 701.
La page co uve rture port e Ie nom de I'e tabli sse m ent aut eur OLI I'on pe ut se
procu rer les rap port s so us co uve rture ca rt on nee .
a
• Cove r design by Chr istine Rus k
i
Fisheries and Marine Service
Technical Report No. 765
February 1978
SEASONAL CHANGES IN THE CONTENT OF NON-METALLIC INORGANIC COMPONENTS
IN THE MARINE ALGA MACROCYSTIS INTEGRIFOLIA
by
J.N.C. Whyte and J.R. Englar
, Industry, Technology and Inspection Directorate
Fisheries and Marine Service
Department of Fisheries and the Environment
Vancouver Technological Research Laboratory
6640 N. W. Marine Drive
Vancouver, B.C.
V6T 1X2
This is the fifth Technical Report from the
Industry, Technology and Inspection Directorate
Vancouver
ii
I
~
Minister of Supply and Services Canada 1978
Cat. No. Fs 97-6/765
ISSN 0701-7626
iii
TABLE OF CONTENTS
Page No.
Abstract
............................................................
iv
1
Introduction
Experimental
Collection and preparation of specimens ............ .....
Methods of analysis.....................................
3
3
Results and Discussion ..............................................
5
(a)
(b)
11
References
Dry weight and ash content of Macrocystis over the
growi ng season ...........................................
15
Table 2.
Halogen content of Macrocystis over the growing season ...
16
Table 3.
Sulphur and corresponding sulphate content of
Macrocystis over the growing season......................
17
Nitrate, carbonate and silica content of Macrocystis
over the growi ng season ..................................
18
Phosphorus and corresponding phosphate content of
Macrocystis over the growing season.......................
19
Boron and corresponding pyroborate content of Macrocystis
over the growing season
20
Tab 1e 1.
Table 4.
Table 5.
Table 6.
/
Table 7.
Mean, minimum and maximum concentration of non-metallic
inorganic components in Macrocystis over the growing
season ...................................................
21
Figure 1.
Macrocystis integrifolia ................ ............ .....
22
Figure 2.
Seasonal variation in the chloride and sulphate contents..
23
Figure 3.
Seasonal variation in the phosphate, nitrate and silica
contents
24
Seasonal variation in the iodide content .................
Seasonal variation in the carbonate and borate contents...
25
26
Figure 4.
Figure 5.
iv
ABSTRACT
Biomass data of the giant ke l p, Macrocystis integrifolia from past
surveys of the coast of British Columbia are presented as an introduction
to the assessment of the seasonal variation in chloride, bromide, iodide,
nitrate, silica, sulphate, carbonate, phosphate and borate contents of the
alga over the growing season, Apri l to October.
The chloride content ranged t hroughout the season from 11.7 to 15.6%,
averaged 13.74%; iodide ranged from 1094 to 1942 ppm, averaged 1547 ppm;
nitrate ranged from 0.57 to 1. 50%, averaged 1.06%; silica ranged from 0.29
to 1.43%, averaged 0.81%; sulphate ranged from 3.21 to 3.60%, averaged
3.39%; carbonate ranged from 0.030 to 0.045%, averaged 0.037%; phosphate
ranged from 0.748 to 1.480%, averaged 1.042%; borate ranged from 219 to
402 ppm, averaged 317 ppm; whereas no bromide above the threshold detection
level of 79.9 ppm could be ascertained in the alga throughout the season.
The commercial significance of the mineral content of Macrocystis
integrifolia is discussed.
Key words: - Macrocystis integrifolia biomass in B.C.: seasonal variation
in minerals in Macrocystis: anionic mineral content of
Macrocystis.
v
Nous presentons des donnees sur la biomasse de Macrocystis
integrifo1ia, tirees d'inventaires anterieurs de la cote de 1a Colombie-
a
Britannique, en guise d'introduction
l'evaluation de la variation
saisonniere de la teneur en ch1orures, bromures, iodures, nitrates,
silice, sulfates, carbonates, phosphates et borates de l'algue au cours
de sa saison de croissance, entre avril et octobre.
Ces variations sont 1es suivantes:
(~:
a
a
13. 74%) ;
iodures:
1094
a
1942 ppm (~:
1.50% (~:
1. 06%) ;
si1ice:
3.60% (~:
3.39%) ;
phosphates:
219
a
402 ppm (~:
317 ppm).
chlorures:
0.29
a
1547 ppm);
1.43% (x:
0.748
a
11.7
0.81%) ;
1.480% (x:
a
15.6%
nitrates:
0.57
sulfates:
3.21
1.042%) ;
borates:
Les bromures n'ont jamais atteint Ie seui1
de detection de 79.9 ppm.
Nous discutons des implications commerciales de la teneur de
Macrocystis integrifo1ia en mineraux.
Mots c1es:
biomasse de Macrocystis integrifolia en C.-B.;
variation
saisonniere de 1a teneur de Macrocystis en mineraux;
teneur de Macrocystis en anions mineraux.
1
INTRODUCTION
Macrocystis integrifolia Bory is a member of the family Lessoniaceae
of the order Laminariales and is distributed from Alaska to California
(Druehl.1970). The alga is commonly known as "giant kelp". "kelp flag".
"sea-ivy". "devil's apron" or "l ong bladder kelp" and is second in abundance
only to Nereocystis luetkeana on the coast of British Columbia (Scagel. 1947).
The major growth of the alga occurs in August at approximately 5 cm/day
but tends to decline rapidly to less than 2 cm/day in February (Lobban. 1977).
Macrocystis requires conditions that are associated with open ocean. thus it
is absent from the inner passages of the coast. This environmental condition may reflect a need for higher salinity during some phase of its life
history but it may also reflect the need for continual scrubbing of the
plant surface by surf action. In relatively still water. such as tanks
irrigated with seawater. whole plants of Macrocystis succumb rapidly to the
smothering and degrading effects of diatom infestation which can be reversed
by agitation of the alga under water (Whyte et al .• 1977). From past
surveys it was noted that areas of full ocean salinity and strong currents
were conducive to the healthy growth of Nereocystis and Macrocystis.
In the summer of 1946 an extensive survey of the B. C. coastline. except ,
for the Queen Charlotte Islands and the West Coast of Vancouver Island. was
undertaken by R.F. Scagel and B.K. Farrar from the Fisheries Research Board
of Canada and the B.C. Research Council respectively. The locations of
significant kelp beds with appropriate estimates of the available and
commercially accessible quantities of seaweed were recorded (Scagel. 1946).
Northern sections of the coastline from Dundas Island south to Aristazabel
Island contained 12.512 tonnes of Macrocystis integrifolia of which 9.462
tonnes were accessible for harvest. Further south the central zone bounded
by Shelter Bay to and including Malcolm Island was estimated to support
7.926 tonnes with 7.775 tonnes commercially accessible for harvest. The
southern coastline of B.C. from Seymour Narrows to the Washington State
boundary was devoid of Macrocystis (British Columbia Research Council. 1948).
Some twenty years later the north coast of Graham Island. Queen
Charlotte Islands. was surveyed for North Pacific Marine Products Ltd .• and
2
an estimated 65,315 tonnes of Macrocystis were recorded from Cape Naden to
just east of Klikidamen Creek (North Pacific Marine Products Ltd., 1967).
This same area was surveyed by the Fisheries Operation in 1973 and the
available Macrocystis estimated to be 68,417 tonnes, which correlated
remarkably well with the previous survey (Blakley et al., 1973) .
Only recently has an assessment been made of the Macrocystis on the
West Coast of Vancouver Island. Based on the kelp inventory method (KIM-I)
developed for floating kelp (Foreman , 1975), an intensive study of the Nootka
Sound area, from Ferrer Point on Nootka Island to Matlahaw Point on the
Hesquiat Peninsula, was conducted by the Marine Resources Branch (Coon et al.,
1976). At mean water level the biomass consisted of 4,578 tonnes of
Macrocystis, 51,894 tonnes of Nereocystis and 9,918 tonnes of mixed beds.
The biomass figure for Nereocystis was considerably lower than that recorded
in the 1965-1967 surveys conducted by the Pacific Kelp Co. Ltd. when only
Nereocystis was inventoried in the Nootka Sound area (Huff and Company,
1967.) Similarly the total kelp biomass supported by Fishery Licence area
12 (Malcolm Island and North East Vancouver Island), when assessed by the
KIM-l procedure, was only 37% of the biomass registered by the 1946 survey;
this section of the coast contained 1,296 tonnes of Macrocystis, 10,418
tonnes of Nereocystis and 1,900 tonnes of mixed beds (Foreman, 1975). These
large discrepancies between surveys may reflect changes to the kelp ecosystem
by environmental stress but is more likely to be a function of the inadequacies of earlier survey procedures which have now been replaced by more
decisive aerial photographic and bed assessment techniques.
A reassessment of the kelp resource in British Columbia using the KIM-l
technique has been undertaken by the Marine Resources Branch, Province of
British Columbia, and the first in a series of five reports concluded that
the biomass in the Estevan Group and Campania Island area consisted of 219
tonnes of Macrocystis, 47,300 tonnes of Nereocystis and 415 tonnes of mixed
species beds available for harvest at mean water level (Field et al., 1977).
From the previous survey work, a total biomass of 93,433 tonnes wet weight
of Macrocystis is considered available on the coast of British Columbia,
however, more pertinent data will become available on completion of the
current studies by the Marine Resources Branch.
3
To complement the survey data on ~. integrifo1ia an understanding of
the nature and seasonality of the chemical constituents of this potentially
commercial alga was essential. A previous report has described the content
of inorganic cations in the alga (Whyte et a1, 1976(a») and as a continuation
of the assessment of inorganic elements in Macrocystis this present report
provides details of the seasonal changes apparent in the content of nonmetallic elements - in some cases as the elements but also as the corresponding oxides found commonly in nature.
EXPERIMENTAL
(a)
Collection and Preparation of Specimens.
Specimens of Macrocystis integrifo1ia were collected from specific beds
at Parsons Spit, Sooke, Vancouver Island, in the middle of the months April
through October. The stipes were cut 2 metres from the apical end, only
from attached plants, then placed in plastic bags in insulated coolers and
transported to the laboratory. The plants were freed from epiphytes and
epifauna, blotted to remove excess surface water, then packaged in zip-lock
plastic bags and stored at -31°C. Freeze drying of the specimens afforded
dry alga which was ground with a porcelain mortar and pestle to 20 mesh size.
Each lot analyzed contained portions from at least 10 plants collected at
the same time and for the analytical determinations the ground samples were
stored in the freeze dryer to ensure anhydrous conditions at all times.
The samples examined for anions were those previously analyzed for cation
components (Whyte et a1., 1976(a»).
(b)
Methods of Analysis.
1.
Chloride, iodide and ether extractable bromide.
Alkali fusion and ashing of the dry algal tissue or an ether extract
of the algal tissue afforded aqueous solutions of the halides which were
subsequently determined by argentimetric titration using an iodide-selective
electrode (Whyte et a1., 1976(b»).
4
2.
Total Bromide.
Assessment of inorganic and organic bromide in the alga involved
liberation of bromine which was measured spectroscopically at 410 nm in a
chloroform extract (Whyte et al., 1975(a)) .
3.
Sulphur (Sulphate).
Any elemental sulphur present in the alga was oxidized to sulphate
by pretreatment with sodium peroxide and was determined by precipitation as
the insoluble barium salt (Whyte et al., 1975(b)).
4.
Nitrate.
The aqueous-methanol extract of the alga (Whyte et al., 1970) was
titrated with saturated silver sulphate solution to remove halides and the
nitrate in the remaining solution was determined by the "known addition
method" using an Orion 92-07 nitrate ion electrode coupled to an Orion
Research Ionalyzer Model 801 digital pH/mV meter interfaced with a printer
(Whyte et al., 1975(b)).
5.
Silica.
Dry alga was ignited at 500°C for 20 hours and the residue acid trea t ed ,
washed free from acid then reignited to provide residual silica which was
weighed (Whyte et al., 1975(b)).
6.
Carbonate.
The carbonate in the dry alga was determined by acid release of carbon
dioxide which was measured by trapping in ethanolic barium hydroxide and
back titrating with standard hydrochloric acid (Whyte et al., 1975(b)).
7.
Phosphorus (Phosphate); Boron (Pyroborate).
With a Jarrell-Ash direct reading emission spectrometer, the phosphorus
and boron content of the alga was determined and converted to the corresponding oxides using the conversion factors for phosphorus to phosphate
(P0 4 3 - ) and boron to pyroborate (B 4072 - ) which were 3.0662 and 3.590
respectively.
5
RESULTS AND DISCUSSION
Over the growing period from April to October, the content of dry matter
in Macrocystis integrifolia ranged from 9.75% to 14.47% and was represented
by a seasonal average of 12.63%. The inorganic ash from the algal solids
over the same period ranged in content from 36.3% to 43.9% and averaged
39.4%, Table 1. Almost half this ash material was comprised of potassium
and sodium with lesser amounts of calcium and magnesium in addition to trace
amounts of other metallic elements (Whyte et al., 1976(a)). The remaining
portion of the inorganic chemical component of the alga consisted of nonmetallic elements.
Oxides of the non-metallic elements, carbon, boron, sulphur, phosphorus,
silicon and nitrogen exist normally as salts in seawater - a medium which is
generally uniform except for seasonal fluctuations in the last three elements
mentioned. The content of phosphate, nitrate and silicon exibit seasonal
variations depending on river effluent, benthos assimilation and the vacillations in the life cycles of siliceous marine organisms. The more constant
anionic components of seawater are chlorine 18980 ppm, sulphate 2649 ppm,
bicarbonate 140 ppm, bromine 65 ppm, borate 26 ppm, fluorine 1.4 ppm and
i odine 0.05 ppm (Sverdrup et al., 1942). Cellular tissue of marine algae
surrounded by these environmental elements can either assimilate these
elements to attain a concentration equilibria, or assimilate then deplete
these elements for growth utilization, or assimilate and concentrate these
el ements for yet unknown functions within the cell or matrix of the algal
tissue. The variation in the amounts of these elements assimilated by
Macrocystis integrifolia over the growing season was investigated.
Of the four halogens in seawater, only fluorine is not accumulated to
any extent in benthos algae (Young et al., 1958).
The use of an iodide selective electrode to detect equivalence points
of halides titrated with standard silver nitrate solution has been demonstrated to provide rapid and accurate results for total chloride, iodide
and ether soluble bromide in algae (Whyte et al., 1976(b)). As total
bromide could not be detected by use of ion electrodes, a spectrometric
6
procedure was used to enable a content in excess of 79.9 ppm to be determined (Whyte et al., 1975(a)).
Results of the halide evaluation for Macrocystis integrifolia over the
growing season are presented in Table 2. The chloride content declined from
the April level of 14.9% to a seasonal low of 11.7% in August then recovered
to afford the highest level in October of 15.6%, Figure 2. A seasonal
average of 13.74% was considerably greater than the 4.4% chloride content of
dry Norwegian seaweed meal from Ascophyllum nodosum which is extensively
used as a feed additive in animal husbandry (Jensen et al., 1968). Equally
high contents of chloride were evident in Nereocystis luetkeana which had
been added to 20% inclusion in the basal diet of pigs without adverse effects
from these high chloride levels (Beames et al., 1977). A small percentage of
the chloride in Macrocystis was ether soluble, 26 ppm, indicating the
presence of chlorocarbon constituents (Whyte et al., 1976(b)).
The iodi ne content of the alga increased from a seasonal low of 1094
ppm in April to a maximum level of 1942 ppm by June. Following a rapid
decline in July the iodine content generally increased towards the end of
the season, Figure 4. The seasonal average of 1547 ppm was within the limits
specified in the Food Chemicals Codex for iodine in dehydrated seaweed,
namely 0.1 % to 0.5%.
Iodine is the principal halide of commercial importance in seaweed
from which it was universally isolated, by sUblimation of the seaweed ash,
until the middle of the twentieth century (Chapman, 1970). Today the
industrial utilization of kelp as a source of iodine is practised to a
limited extent only in Russia, Japan and China (Levring et al., 1969)
since alternate sources of iodine - the mother liquor of Chile saltpetre have become more economically feasible. Nevertheless, iodine in seaweeds
is still recognised as a dietary supplement for animal feed or for human
consumption as a pharmaceutical grade kelp meal retailed in tablet form, to
eradicate disease resulting from iodine deficiency. Seaweed meal is added
as a dietary supplement for animal and poultry feed at an estimated total
world consumption of 101,600 tonnes per annum (Naylor, 1976).
In China, intensive breeding and cultivation procedures have produced
two new varieties of Laminaria japonica with high iodine contents and
7
fast growth rates which have enhanced the production of this subsidiary food
"haidai" (Section of Seaweed Genetics and Breeding, Academia Sinica, 1976).
Use of seaweed meal in agriculture and horticulture offers considerable
practical advantages in overcoming an increasingly iodine deficient agricultural environment (Jensen, 1971). Although part of the iodine in algae
is covalently bonded in the form of iodoamino acids (Scott, 1954) or volatile
halocarbons (Moore, 1977) the majority is considered to be present in an
inorganic form; no ether soluble iodine was detected in Macrocystis (Whyte
et al., 1976(b)). It would appear that the iodine in seaweed meal is
strongly chelated as it remains stable for years in contrast to the mineral
rich animal feedstuff additives which lose inorganic iodine quite rapidly
(Jensen, 1971).
The range of iodine in Macrocystis, 1094 to 1942 ppm is much lower than
the 0.1 to 1.0% recorded for the Laminariales in the U.K. where it was
observed that the higher iodide content was associated with plants growing
at the lowest levels of their vertical distribution (Black, 1949). These
lower values for iodide in Macrocystis may be equated to the surface location of the samples examined. However the iodide content of Macrocystis was
generally higher than the 824 to 1412 ppm afforded by the dry Norwegian
kelpmeal from Ascophyllum nodosum (Jensen, 1971).
Total bromide content, as detected by spectroscopic analysis, did not
exceed the limit of detection, 79.9 ppm, and the ether soluble halide in
Macrocystis was less than 15 ppm, the limit of the electrode procedure
employed. Elevated bromine levels have been associated with bromocarbon
compounds generally in the red algae (Crews, 1977; Fenical, 1976; McConnell
et al., 1977) although several organic bromine constituents in brown algae
have been reported but at the parts per billion range (Lunde, 1973). As the
level of bromine in seawater is about 65 ppm, it can be concluded that
Macrocystis does not concentrate this element from the aquatic environment.
Measurement of total sulphur in Macrocystis by precipitation of the
barium sulphate, following alkaline oxidative fusion of the dry alga, yielded
the total sulphur content of the alga in addition to the corresponding oxide.
The sulphate ion exists 39% as the free ion, 37% as the sodium salt and 19%
as the magnesium salt in seawater (Burton, 1977) whereas in algae it is
8
associated principally with the polysaccharide components as half ester
sulphate groups attached to fucoidan of the brown algae and carrageenans
and agaroids of the red algae. Seasonal changes in the content of total
sulphur and corresponding sulphate in Macrocystis are presented in Table 3.
An average 3.39% sulphate content was observed from values which fluctuated
from 3.21 to 3.60% throughout the season with peak levels being registered in
June and September. The 2.5 to 3.5% total sulphur in Norwegian kelpmeal is
considerably higher than the 1.07 to 1.20% total sulphur in Macrocystis and
suggests a much lower content of fucoidan in the Pacific seaweed.
Although total nitrogen contents of marine algae have been reported in
the literature (Vinogradov, 1953), very few measurements of the nitrate
content of benthos algae have been performed (Whyte et al., 1975(b)).
Nitra te content was determi ned by the "known additi on method" on an aqueous
methanol extract of the alga following removal of the halide from the solution by precipitation with aqueous silver sulphate. An average nitrate
content of 1.06% was observed from a seasonal spread of 0.57% to 1.50%,
Table 4. In spring and summer the nitrate levels were above 1% but a marked
decline in the latter half of the growing season provided the lowest level
of 0.57% in October, Figure 3. This decline may reflect the continued
conversion of nitrate to organic nitrogenous compounds in addition to depletion of the environmental nitrate.
Acid leaching of an ashed sample of Macrocystis yielded the silica
content which varied from 0.29 to 1.43% throughout the season and provided a
seasonal average of 0.81 %, Table 4. A general increase in siliceous content
as the season progressed, Figure 3, illustrated the increased susceptibility
of the alga to the encrusting bryozoan Membranipora membranacea.
Carbonate in the alga, Table 4, was determined by acid liberation of
carbon dioxide and the subsequent determination of this gas in an apparatus
developed for estimation of alginic acid by acid decarboxylation (Whyte et
al, 1974). A general increase in carbonate occurred throughout the season,
Figure 5, from a minimum 0.03% in May to a maximum level of 0.045% by
October, yielding a seasonal average of 0.037%. Increased attachment of
calcareous organisms coupled with a decline in the photosynthetic process
9
of converting inorganic carbon to sugar components in the alga are probable
reasons for this seasonal trend.
Phosphate and borate contents of the alga were calculated from values
for the parent elements obtained by emission spectrometry and the results
are presented in Tables 5 and 6. From the lowest value for phosphate in
April, 0.748%, the content varied only slightly until August, thereafter
rapid accumulation occurred yielding the seasonal high in October of 1.48%,
Figure 3. This cumulative effect at the end of the season reflects the
decreased utilization of this micronutrient by the surrounding biota allowing
for continued accumulation and maintenance by the alga.
Seasonal variations in the boron and corresponding pyroborate contents
of the alga are presented in Table 6. An average value of 317.4 ppm borate was
obtained from a range of 218.6 ppm in April to 402.1 ppm in June, Figure 5.
The exact ionic form of boron in Macrocystis is not known, however boratecalcium- sulphated polysaccharide complexes are considered to exist in the
green alga Ulva lactuca (Haug, 1976). A comparison of the results in Table
6 with the calculated pyroborate content of seawater, 65 ppm, illustrates
the ability of this alga to concentrate borate ion from seawater.
Mean, minimum and maximum levels of the non-metallic inorganic elements
in Macrocystis are illustrated in Table 7. The principal anions totalling
19.19% of the alga (13.7% chloride, 3.39% sulphate, 1.04% phosphate and
1.06% nitrate) when combined with the 18.43% of major cations in the alga
(13.1 % potassium, 4.14% sodium, 0.65% calcium and 0.54% magnesium) provide
a total inorganic content, neglecting minor and trace elements, of 37.62%.
This figure is lower than the 39.4% average ash content, Table 1, however
when the cations are expressed as their corresponding oxides, which are
undoubtedly formed in part under ashing conditions, then the inorganic
content of 42.37% is obtained, which when averaged with the previous value
provides a figure of 39.99% in reasonably good agreement with the experimental ash content.
Relative to the Atlantic species of the Laminariaceae (Black, 1950)
and Fucaceae (Jensen et al., 1968) which have approximately 20% ash contents,
the Pacific coast Macrocystis integrifolia concentrates high levels of
10
inorganic elements, particularly potassium. This high proportion of inorganic
elements would limit the macronutrient value of Macrocystis integrifolia but
would assure its utilization as a natural mineral supplement for livestock
feed, for health foods and for general agricultural or horticultural applications to overcome trace element deficiencies and eradicate nutritional
disorders.
11
REFERENCES
Beames. R.M .• R.M. Tait. J.N.C. Whyte and J.R. Englar. 1977. Studies
on the utilization of kelp (Nereocystis luetkeana) meal by pigs.
1. Nutrient balance experiments with growing pigs recelvlng
diets containing from 0% to 20% kelp meal. Can. J. of Animal
Science. 57. 121.
Black, W.A.P . 1949. Seasonal variations in chemical composition of
littoral seaweeds common to Scotland. Part II. J. Soc. Chern.
Ind. 68. 183 and references cited therein.
Black. W.A.P. 1950. The seasonal variation in weight and chemical
composition of the common British Laminariaceae. J. Marine
Biol. Assoc. of the U.K. 29. 45.
Blakley. B.B. and W.T. Chalmers. 1973. Masset Kelp Inventory. Report
by Dept. of Environment, Fisheries Operation. Vancouver. 75 pp.
British Columbia Research Council. 1948. Marine plants of economic
importance in British Columbia coastal waters. Technical
Bulletin No. 10. 45 pp.
Burton. J.D.
1977.
Chapman. V.J. 1970.
p. 24.
The composition of sea water.
Seaweeds and their uses.
Chern. and Ind. 550.
Methuen and Co. Ltd . .
Coon. L.M .• E. J. Field and Canadian Benthic Ltd. 1976. Nootka Sound
kelp inventory. 1975. B.C. Marine Resources Branch, Fish.
Management Report No.2. 27 pp.
Crews. P.
1977. Monoterpene halogenation by the red alga Plocamium
oregonum. J. Org. Chern. 42. 2634.
Druehl, L.D. 1970. The pattern of Laminariales distribution in the
Northeast Pacific. Phycologia 9. 237.
12
Fenica1, W.
1976. Chemical variation in a new bromochamigrene
derivative from the red seaweed Laurencia pacifica.
Phytochemistry. 15, 511.
Field, E.J., L.M. Coon, W.E.L. Clayton and E.A.C. Clark. 1977. Kelp
inventory, 1976. Part I. The Estevan Group and Campania
Island. B.C. Marine Resources Branch, Fish. Management Report
No.9. 19 pp.
Foreman, R.E. 1975. A method for inventory of floating kelps and its
application to selected areas of kelp license area 12 (KIM-I).
B.E.R.P. report 75-1. 81 pp .
Haug, A.
1976. The influence of borate and calcium on the gel formation
of a sulfated polysaccharide from U1va 1actuca. Acta.
Chern. Scand. B30, 562.
Huff, M.W. and Company. 1967. Occurrence and distribution of seaweeds,
1965, 66 and 67. A quantitative survey of portions of the
east and west coasts of Vancouver Island, British Columbia.
40 pp.
Jensen, A.
1971. The nutritional value of seaweed meal for domestic
animals. Proc. Int1. Seaweed Symp. 7,7.
Jensen, A. , H. Nebb and E.A. Saeter. 1968. The value of Norwegian
seaweed meal as a mineral supplement for dairy cows.
Norwegian Institute of Seaweed Research, Report No. 32. 35 pp.
Levring, T. , H.A. Hoppe and O.J. Schmid. 1969. Marine algae, a survey
of research and utilization. Cram, De Gruyter and Co. 421 pp.
Lobban, C.S. 1977. Growth of Macrocystis integrifo1ia in Barkley Sound,
B.C. B.C. Marine Resources Branch, Fish. Management Report
No. 10. 9 pp.
13
Lunde, G.
1973. The presence of volatile, nonpolar bromo organic compounds
synthesized by marine organisms. J. Amer. Oil Chemists' Soc.
50. 24.
McConnell, O. and W. Fenical. 1977. Halogen chemistry of the red alga
Asparagops is. Phytochemi s try. 16, 367.
Moore, R.E.
1977. Volatile compounds from marine algae.
Chemical Research. 10. 40.
Accounts of
Naylor, J.
1976. Production, trade and utilization of seaweeds and
seaweed products. FAO Fisheries Technical Paper No. 159. 73 pp.
North Pacific Marine Products Ltd. Report. 1967. Summer survey of marine
plants. Masset, Queen Charlotte Islands. 62 pp.
Scagel, R.F. 1946. A report of a seaweed survey of the coast of British
Columbia. 47 pp.
Scagel, R.F. 1947. An investigation on marine plants near Hardy Bay,
B.C. Report to Provo Dept. Fisheries. 1, 70 pp.
Scott, R.
1954. Observations on the iodo-amino-acids of marine algae
using iodine-13l. Nature 173, 1098.
Section of Seaweed Genetics and Breeding, Academia Sinica. 1976. The
breeding of new varieties of Haidai (Laminaria japonica, Aresch).
with high production and high iodine content. Scientia Sinica.
19, 243.
Sverdrup, H.V., M.W. Johnson and R.H. Fleming. 1942.
Prentice-Hall Inc., New York. p. 165.
The Oceans.
Vinogradov, A.P. 1953. The elementary chemical composition of marine
organisms. Sears Foundation for Marine Research, Yale University.
647 pp.
14
Whyte, J.N.C. and J.R. Eng1ar, 1974. Determination of uronic acid
content of saccharides by acidic decarboxylation: a simplified
procedure. Analytical Biochemistry 59, 426.
Whyte, J.N.C. and J.R. Englar. 1975 (a). Estimation of the halogen content
of the marine alga Nereocystis luetkeana over the growing season.
Fisheries and Marine Service Technical Report No. 561. 23 pp.
Whyte, J.N.C. and J.R. Englar. 1975 (b). Composition of the non-metallic
inorganic components of the marine alga Nereocystis luetkeana
over the growing season. Fisheries and Marine Service Technical
Report No. 568. 34 pp.
Whyte, J.N.C. and J.R. Englar. 1976 (a). The content of inorganic elements
in the marine alga Macrocystis integrifo1ia over the growing
season. Fisheries and Marine Service Technical Report No. 695.
28 pp.
Whyte, J.N.C. and J.R. Englar. 1976 (b). Determination of halogens in
marine algae by use of an ion-selective electrode. Analyst 101,
815.
Whyte, J.N.C. and J.R. Englar. 1977. Aspects of the production of herring
roe on Macrocystis integrifolia in Georgia Strait locations.
Fisheries and Marine Service Technical Report No. 751,
28 pp.
Whyte, J.N.C. and B.A. Southcott. 1970. An extraction procedure for plants:
extracts from the red alga Rhodomela larix. Phytochemistry 9,
1159.
Young, E.G. and W.M. Langille. 1958. The occurrence of inorganic elements
in marine algae of the Atlantic provinces of Canada. Can. J.
Botany, 36, 301.
15
Table 1.
Month
Dry weight (freeze dried) and ash content of
Macrocystis integrifolia over the growing season.
(% Fresh Plant)
April
Ash (% Dry Weight)
Dry Weight
Total
Insoluble
9.75
37.1
7.0
May
12.75
42.6
8.1
June
12.55
36.5
5.9
July
11.75
36.3
4.9
August
14.47
37.9
6.4
September
13.95
41.6
8.1
October
13.16
43.9
8.0
16
Table 2.
Month
Halogen content of Macrocystis integrifolia
over the growing season.
Chloride
(% Dry Weight)
Iodide
Bromide
Ether Extract
(ppm Pry Weight)
(ppm Dry Weight)
Bromide
Total
(ppm Dry
l~eight)
Apri 1
14.9
1094
< 15
<79
May
14.4
1726
< 15
<79
June
13.6
1942
< 15
<79
July
12.5
1385
< 15
<79
August
11. 7
1555
< 15
<79
September
13 . 5
1460
< 15
<79
October
15.6
1667
< 15
<79
17
Table 3.
Month
Sulphur and corresponding sulphate content of
Macrocystis integrifolia over the growing season.
Sulphur
(% Dry Weight)
Sulphate
(% Dry Weight)
April
1.09
3.28
May
1.11
3. 33
June
1.19
3.58
July
1.08
3. 25
August
1.07
3.21
September
1. 20
3. 60
October
1.17
3.50
18
Table 4.
Nitrate, carbonate and silica content of
Macrocystis integrifolia over the growing season.
Nitrate
Sil i ca
Carbonate
(% Dry Wei ght)
(% Dry Weight)
(% Dry Weight)
April
1.18
0.74
0.033
May
1. 50
0.29
0.030
June
1. 32
0.56
0.039
July
1.45
0.40
0.036
August
0.72
0. 87
0.037
September
0.66
1.43
0.042
October
0.57
1. 36
0.045
Month
19
Table 5.
Phosphorus and corresponding phosphate content of
Macrocystis integrifolia over the growing season .
Month
Phosphorus
(% Dry Wei ght)
Phosphate
(% Dry Weight)
April
0.244
0.748
May
0.327
1.002
June
0.299
0.916
July
0.322
0.987
August
0.274
0.840
September
0.432
1. 324
October
0.483
1. 480
20
Table 6.
Month
Boron and corresponding pyroborate content of
Macrocystis integrifolia over the growing season .
Boron
(ppm Dry Weight)
Pyroborate
(ppm Dry Weight)
April
60.9
218.6
May
79.7
286.1
June
112.0
402.1
July
85 . 3
306.2
August
91. 3
327.8
102.0
366 . 2
87.7
314 . 8
September
October
21
Table 7.
Mean, minimum and maximum concentrations of
non-metallic inorganic components in
*
Macrocystis integrifolia over the growing season.
Component
Mean
Range
Chloride, %
13 . 7
11. 7 - 15.6
Sulphate, %
3.39
3.21 - 3.60
Phosphate, %
1. 04
0.75 - 1.48
Ni trate, %
1.06
0.57 - 1. 50
Si 1i ca, %
0.81
0.29 - 1. 43
Carbonate, %
0.037
0.030- 0.045
Iodide, ppm
1547
1094 - 1942
Pyroborate, ppm
317
219 -
402
Bromide, tota 1, ppm
<79
<79
Bromide, organic, ppm
<15
oo-
* Dry Weight basis.
<15
22
Fig.1
Apical
Scimitar
Steri Ie
Laminae
""
Pneumatocyst
Stipe
Laminae
Rhizome
-
Haptera
Macrocyst is integrifol ia
23
Fig .2
Chloride Content
16
15
14
13
..
Q)
en
co
c
..
Q)
(.)
12
Q)
D.
11
4·0
Sulphate Content
3·5
3·0
Apr.
May
Jun .
Jul.
Aug.
Sep.
Oct.
24
Phosphate Content
Fig.3
-0-
Nitrate Content
Silica Content
8-
1·6
1·4
1·2
1·0
Q)
m
co
.,
c:: 0·8
G)
(J
...
G)
c..
0·6
0·4
0·2
o~~----~----~----~----~----~----~--
Apr.
May
Jun.
Jul.
Aug. ·
Sep.
Oct.
Iodide Content
25
Fig.4
1900
1800
1700
1600
•
E
ci•
1500
Q.
1400
1300
1200
1100
o
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oc t.
26
Fig.5
Carbonate Content
Borate Content
G-
0-
460
420
380
•
E•
340
Co
•
Co
300
260
220
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.