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Effects of Fluorescent Brighteners on Growth and Morphology of the Red Alga Antithamnion Kylinii
Abstract
Four fluorescent brighteners (Fluorescent Brightener 28, Fluostain 1, Fluostain II and Cellufluor) were examined with respect to their binding affinity, toxicity (their ability to stunt growth), and teratogenic effects on the red alga Antithamnion kylinii. Maximum binding occurred with FB-28 and F-II but these stains showed the greatest inhibition of growth when plants were exposed to concentrations of 0.01% for 30 min. Filaments incubated in low stain concentrations (0.0005%) showed cell abnormalities with all stain types, with FB-28 producing the most extreme deformations of both intercalary and apical cells. The experiments suggest that extensive experimentation is required to develop protocols for vital cell wall stains that minimize toxicity and maximize binding.
... Decades ago, the remarkably high stability of FWAs had provoked intensive concerns about their potential toxicity. Though the real impact of FWAs on human health was still not conclusive yet, their developmental toxicity and alteration effect of gene expression in model animals had been experimentally evidenced (Belliveau et al. 1990;Jung et al. 2012). With regard to these potential risks, food safety authorities around the world had stipulated restrictions and limits for migratable FWAs in food contacting materials. ...
In recent years, there was increasing concerns on food safety issues associated with fluorescent whitening agents from package materials. Here, we reported the development of a facile and reliable method suitable for high-throughput quantification and identification of two common fluorescent whitening agents (FWA 184 and FWA 367) in cereal products (wheat and rice flour), platformed by high-performance thin-layer chromatography. First, the sample preparation and cleanup were rapidly accomplished via an optimized solid–liquid extraction. The extracts and reference standard were simultaneously separated on silica gel plates, using the mixture of toluene and ethyl acetate (10/0.3, v/v) as the mobile phase. Then, rapid quantification was performed with densitometry in fluorescent mode (365 </ 400 nm, mercury lamp), reaching limit of detection 18–21 μg/kg; meanwhile, good linearity (R² = 0.9999) of quantification can be achieved within a broad range (100–2000 pg/band). With real cereal samples, the quantitative measurement was validated, showing good spike-recovery rates (88.0–108.4%). Furthermore, the conclusive identification of the targeted band was directly realized by in situ mass detection, providing compound-specific signals (m/z 363.09 and 431.18, for FWA 184 and FWA 369, respectively) as the fingerprint evidence. The proof-of-concept result of this work demonstrated that HPTLC as a versatile analytical platform can achieve an ideal balance among throughput, simplicity, and detectability, therefore, particularly suitable for screen-oriented food analysis.
... Although Calcofluor White is absorbed to the crystalline core of CMF (Herth and Schnepf 1980; Burgess 1983), it also interferes with cellulose crystallization (Haigler et al. 1980 ). Therefore , interpreting presumed CMF patterns at the surface of regenerating protoplasts is only correct where cells have been exposed to the dye for just a brief period. Abnormalities in development and growth, even at a relatively low dye concentration, are unavoidable (Itoh et al. 1984; Belliveau et al. 1990). We have already addressed the question whether Calcofluor White is specific enough for crystalline cellulose. ...
Monitoring cell-wall formation in vivo with Fluorescent Brightener 28, by fluorescence microscopy, revealed that tobacco protoplasts regeneration started within 30 min indicated by cellulose microfibril formation at distinct sites on the protoplast surface. Oriented cellulose microfibril deposition was apparent before elongation and indicated the early polarization of protoplasts. The sequence of cellulose microfibril deposition correlates with an helicoidal-like texture. Within 6 h, a texture was completed. Tobacco suspension cells, stained by decolourized aniline blue, showed radiant granular callose fluorescence in cell plates and transverse walls. During the culture cycle of suspension cells, transverse fibrillar deposits of callose gradually appeared in the lateral walls during the log-phase, and subsequently disappeared in the early stationary phase of the cell culture. Similar callose transitions were observed in regenerated elongating protoplasts. Culture cells of Morinda citrifolia L. only showed transient granular depositions in the lateral walls. The callose formations did not result from artificial wounding. The transient appearance of callose might be related to cellulose microfibril deposition. Keywords: aniline blue, Calcofluor White ST, callose, cellulose, Fluorescent Brightener 28, Morinda citrifolia, Nicotiana tabacum.
... Fluorescent brighteners have been used extensively to study algal morphogenesis (Belliveau et al. 1990). These reagents enable visualization of living algae cell walls under fluorescent microscopy. ...
Zygospore formation in different strains of the Closterium peracerosum-strigosum-littorale complex was examined in this unicellular isogamous charophycean alga to shed light on gametic mating strains in this taxon, which is believed to share a close phylogenetic relationship with land plants. Zygospores typically form as a result of conjugation between mating-type plus (mt(+)) and mating-type minus (mt(-)) cells during sexual reproduction in the heterothallic strain, similar to Chlamydomonas. However, within clonal cells, zygospores are formed within homothallic strains, and the majority of these zygospores originate as a result of conjugation of two recently divided sister gametangial cells derived from one vegetative cell. In this study, we analyzed conjugation of homothallic cells in the presence of phylogenetically closely related heterothallic cells to characterize the reproductive function of homothallic sister gametangial cells. The relative ratio of non-sister zygospores to sister zygospores increased in the presence of heterothallic mt(+) cells, compared with that in the homothallic strain alone and in a coculture with mt(-) cells. Heterothallic cells were surface labeled with calcofluor white, permitting fusions with homothallic cells to be identified and confirming the formation of hybrid zygospores between the homothallic cells and heterothallic mt(+) cells. These results show that at least some of the homothallic gametangial cells possess heterothallic mt(-)-like characters. This finding supports speculation that division of one vegetative cell into two sister gametangial cells is a segregative process capable of producing complementary mating types.
To understand the development of organisms we need to understand the structure and function of the component cells. All organisms have a cellular basis, and cellular components have a defined macromolecular organization. The specific molecular organization of cell organelles and their components is associated with their specialized functions (Alberts et al, 1994). By visualizing cell components and examining their occurrence, abundance and localization within specific cell types, one is better able to appreciate organelle activity and its role in cellular processes. We can now obtain a great deal of information about cell components by the application of fluorescent probes and microscopy. In this chapter, five aspects of cells are highlighted: cell walls, chloroplasts, mitochondria, cytoskeleton and nuclei. These cell components are found in most groups of algae, and, other than cell walls and chloroplasts, in virtually all other eukaryotic taxa.
Cell-wall synthesis in Chlorella vulgaris, an autospore-forming alga, was observed using the cell wall-specific fluorescent dye Fluostain I. The observation suggested two clearly distinguishable stages in cell-wall synthesis: moderate synthesis during the cell-growth process and rapid synthesis at the cell-division stage. We used electron microscopy to examine the structural changes that occurred with growth in the premature daughter cell wall during the cell-growth and cell-division phases. The cell began to synthesize a new daughter cell wall shortly after its release from the autosporangium. A very thin daughter cell wall, with a thickness of about 2 nm, was formed inside the mother cell wall and completely enveloped the outer surface of the plasma membrane of the cell. The daughter cell wall gradually increased in thickness from 2 to 3.8 nm. During the protoplast-division phase in the cell-division stage, the daughter cell wall expanded on the surface of the invaginating plasma membrane of the cleavage furrow, accompanied by active synthesis of the cell wall, which increased in thickness from 3.8 to 6.1 nm. The daughter cell matured into an autospore while completely enclosed by its own thickening (from 6.1 to 17 nm) wall. Finally, the released daughter cell was enclosed by its own cell wall after the mother cell wall burst. The daughter cell with mature wall thickness (17-21 nm) emerged as a small, but complete, autospore.
Non-flagellated vegetative green algae of the Trebouxiophyceae propagate mainly by autosporulation. In this manner, the mother cell wall is shed following division of the protoplast in each round of cell division. Binary fission type Nannochloris and budding type Marvania are also included in the Trebouxiophyceae. Phylogenetic trees based on the actin sequences of Trebouxiophyceae members revealed that the binary fission type Nannochloris bacillaris and the budding type Marvania geminata are closely related in a distal monophyletic group. Our results suggest that autosporulation is the ancestral mode of cell division in Trebouxiophyceae. To elucidate how non-autosporulative mechanisms such as binary fission and budding evolved, we focused on the cleavage of the mother cell wall. Cell wall development was analyzed using a cell wall-specific fluorescent dye, Fluostain I. Exfoliation of the mother cell wall was not observed in either N. bacillaris or M. geminata. We then compared the two algae by transmission electron microscopy with rapid freeze fixation and freeze substitution; in both algae, the mother cell wall was cleaved at the site of cell division, but remained adhered to the daughter cell wall. In N. bacillaris, the cleaved mother cell wall gradually degenerated and was not observed in the next cell cycle. In contrast, M. geminata daughter cells entered the growth phase of the next cell cycle bearing the mother and grandmother cell walls, causing the uncovered portion of the plane of division to bulge outward. Such a delay in the degeneration and shedding of the mother cell wall probably led to the development of binary fission and budding.
The seasonal variations of growth in Chondrus crispus Stackhouse were studied by using a vital, fluorescent, cell-wall stain called Cellufluor. In situ growth is not only apical but is extended at least to the upper half of the thallus; it is slow at the beginning of spring, increases towards the end, slows down at the beginning of summer, and increases again to reach a maximum in autumn. It is minimal during winter. The same pattern of growth occurs for the two dissimilar studied forms of the alga, although the rate is greater in the infralittoral than in the midlittoral form.
Calcofluor White (a fluorochrome dye) affected the growth of Geotrichum lactis by causing lysis of cells at the hyphal tips. This effect was prevented by the presence of an osmotic stabilizer. The growth of Saccharomyces cerevisiae was also affected, and multicellular aggregates were formed because of incomplete separation of mother and daughter cells; fluorescence microscopy indicated the presence of abnormally thick septa. The formation of rudimentary wall material by G. lactis protoplasts was promoted by Calcofluor or Congo red (another dye). The rate of chitin synthesis in protoplasts and growing cells was enhanced by both dyes. In contrast, both dyes inhibited chitin and beta (1,3)-glucan synthases in isolated cell-free systems. Degradation rates for beta (1,3)-glucan or chitin were not affected significantly by the dyes. Wheat germ agglutinin also affected chitin synthesis in protoplasts.
BELLIVEAU. 1990. Diffuse growth, a new pattern of cell wall deposition for the Rhodophyta. Phyc% gia 29: 98-102. By means of calcofl uor staining, cell elongation measurements, and microspectrofluorometry, diffuse cell wall deposition is demonstrated for the first time in the red algae in Audouinella dasyae (Ac rochaetiaceae, Acrochaetiales), Spermothamnion repens and Tiffaniella snyderae (Ceramiaceae, Cer amiales). Measurements of cell length indicate that cell elongation is occurring, but neither visual inspection nor microspectrofluorometry of cells stained with calcofluor show band deposition. The Rhodophyta thus possess all three mechanisms of cell wall deposition known to operate in plants: apical cell wall deposition in all apical cells examined to date, and either band deposition or diffuse deposition in intercalary cells. These results suggest that patterns of wall deposition may be a useful systematic character in Ceramiaceae, with the tribe Spermothamnieae possessing diffuse growth, and other tribes investigated to date exhibiting band growth.
The influence of the light microscopical stains, Calcofluor white and Congo red, on the process of chitin microfibril formation of the chrysoflagellate alga Poterioochromonas stipitata was studied with light and electron microscopy. There is a concentration-dependent inhibition of lorica formation with both dyes. In the presence of the inhibitors malformed loricae are made, which do not show the usual ultrastructure and arrangement of the chitin microfibrils. Instead of long, laterally associated microfibrils, short rods or irregular networks of subelementary (15-25 A) fibrils are found. Microfibril assembly obviously takes place on the accessible outside of the plasma membrane. There must be a gap between the polymerization and microfibril formation reactions, allowing the stains to bind to the polymerized subunits. Thus, later association of these units to form microfibrils is disturbed. The microfibril-orienting mechanism also depends on normal microfibril formation. A model summarizing these hypotheses is suggested.
The cell wall of Fucus evanescens eggs, at about 2 hours after liberation from receptacles, was labeled with the fluorescent dye, calcofluor white M2R, and the eggs were cultured in normal sea water. Later, at various times, the fluorescence was inspected. The results were as follows. (1) The cell wall was uniformly labeled in the beginning. (2) The peculiar region exhibiting a specially high fluorescence appeared before actual formation of the rhizoid protuberance. (3) The distal region of the protuberance was almost defective of the fluorescence, while the basal region exhibited a specially strong fluorescence. Observation with a polarizing microscope revealed that birefringence of the cell wall is uniformly characterized in early stages, but a region of a strong birefringence appears just before the actual formation of the rhizoid protuberance. The distal cell wall of the protuberance exhibits very faint, while the basal cell wall displays very strong birefringence. From these observations, it seems that the rhizoid protuberance is not a mere transformation by protrusion of the corresponding region of the former cell, but it is accompanied by a de novo formation of the cell wall and cytoplasm.
Protoplasts of the filamentous green alga Mougeotia sp. are spherical when isolated and revert to their normal cylindrical cell shape during regeneration of a cell wall. Sections of protoplasts show that cortical microtubules are present at all times but examination of osmotically ruptured protoplasts by negative staining shows that the microtubules are initially free and become progressively cross-bridged to the plasma membrane during the first 3 h of protoplast culture. Cell-wall microfibrils areoobserved within 60 min when protoplasts are returned to growth medium; deposition of microfibrils that is predominantly transverse to the future axis of elongation is detectable after about 6 h of culture. When regenerating protoplasts are treated with either colchicine or isopropyl-N-phenyl carbamate, drugs which interfere with microtubule polymerization, they remain spherical and develop cell walls in which the microfibrils are randomly oriented.
Cell elongation in the Ceramiaceae typically occurs by means of one or two bands located apically and (or) basally in each cell. In axial cells of Antithamnion defectum two bands are present; however, most cell elongation occurs as a result of new wall deposition in bands at the base of each axial cell. In cells of determinate branches, only the basal band is present. In experimental conditions in which apical cells of indeterminate branches are differentially excised, location of the primary elongation band can be reestablished in relation to remaining indeterminate axes. Thus, the primary elongation band in axial cells is always basal with respect to indeterminate apical cells. When all indeterminate apices are removed, band growth becomes highly disrupted, and diffuse, irregularly located bands are formed. These results suggest that regulation of band position and elongation is through apical control.
Calcofluor White ST is a fluorescent brightener that has previously been shown to alter cellulose ribbon assembly in the bacteriumAcetobacter xylinum. In this report, we demonstrate that Calcofluor also disrupts cell wall assembly in the eukaryotic algaOocystis apiculata. When observed with polarization microscopy, walls altered by Calcofluor show reduced birefringence relative to controls. Electron microscopy has shown that these altered walls contain regions which consist primarily of amorphous material and which generally lack organized microfibrils. We propose that wall alteration occurs because Calcofluor binds with the glucan chains polymerized by the cellulose synthesizing enzymes as they are produced. As a consequence, the glucan chains are prevented from co-crystallizing to form microfibrils. Synthesis of normal walls resumes when Calcofluor is removed, which is consistent with our proposal that Calcofluor acts by direct physical interaction with newly synthesized wall components.
Several types of fluorescent patterns at the cell wall/plasmalemma interface have also been observed following Calcofluor treatment. Fluorescent spots, striations; helical bands, and lens-shaped thickenings have been documented. Each of these patterns may be the result of the interaction of Calcofluor with cellulose at different spatial or temporal levels or from varying concentrations of the brightener itself. Helical bands and lens-shaped thickenings also have been examined with the electron microscope. Like other regions of wall alteration, they are found to contain primarily amorphous material. Finally, we note that cells with severely disrupted walls are unable to complete their normal life cycle.
Summary Microtubule reorganization and cell wall deposition have been monitored during the first 30 hours of regeneration of protoplasts of the filamentous green algaMougeotia, using immunofluorescence microscopy to detect microtubules, and the cell-wall stain Tinopal LPW to detect the orientation of cell wall microfibrils. In the cylindrical cells of the alga, cortical microtubules lie in an ordered array, transverse to the long axis of the cells. In newly formed protoplasts, cortical microtubules exhibit some localized order, but within 1 hour microtubules become disordered. However, within 3 to 4 hours, microtubules are reorganized into a highly ordered, symmetrical array centered on two cortical foci. Cell wall synthesis is first detected during early microtubule reorganization. Oriented cell wall microfibrils, co-aligned with the microtubule array, appear subsequent to microtubule reorganization but before cell elongation begins. Most cells elongate in the period between 20 to 30 hours. Elongation is preceded by the aggregation of microtubules into a band intersecting both foci, and transverse to the incipient axis of elongation. The foci subsequently disappear, the microtubule band widens, and microfibrils are deposited in a band which is co-aligned with the band of microtubules. It is proposed that this band of microfibrils restricts lateral expansion of the cells and promotes elongation. Throughout the entire regeneration process inMougeotia, changes in microtubule organization precede and are paralleled by changes in cell wall organization. Protoplast regeneration inMougeotia is therefore a highly ordered process in which the orientation of the rapidly reorganized array of cortical microtubules establishes the future axis of elongation.
Development of the vegetative gametophyte of Batrachospermum sirodotii Skuja was examined with light and both transmission and scanning electron microscopy. Patterns of wall growth were followed using the Calcofluor White ST pulse-chase method. Thallus structure was analysed in terms of the pattern of development of the apical, periaxial and pleuridial initials that generate the axial and whorled lateral filaments characteristic of Batrachospermum. Apical cells of axial filaments elongate initially by tip growth with the nucleus maintaining a distal position. Nuclear division is horizontal. One daughter nucleus migrates basipetally and a thin, convoluted annular septum and perforate-occluded pit connection are then formed. Elongating axial cells subsequently extend by wall deposition at the base of the cell. Periaxial cells are initiated laterally and elongate primarily by tip growth while the nucleus remains within the axial cell. The nucleus then migrates to the boundary between the initial and the axial cell, divides, and one daughter nucleus moves into the initial and the other back into the axial cell. A slightly irregular annular septum and simple-occluded pit connection are then formed. Pleuridial cell initials begin as terminal to subterminal protuberances on periaxial or pleuridial cells. They first extend by tip growth and later by bipolar band growth. The nucleus remains within the parent cell as the pleuridial initial expands and a narrow septal ring is formed between the two cells. It then migrates through the septal ring into the initial and divides transversely. One nucleus passes back into the parent cell and a thick, flat septum and perforate-occluded pit connection are formed. It is concluded that the potentially indeterminate axial filaments and the determinate lateral pleuridia represent distinct developmental types in Batrachospermum.
Protoplasts of Boergesenia forbesii (Harvey) were treated with inhibitors of protein synthesis in order to investigate their effects on cellulose synthesis. Cellulose synthesis was reversibly inhibited by 10 μM cycloheximide as assayed by fluorescence microscopy of Tinopal binding to cellulose. Freeze fracture and image analysis of cycloheximide- treated cells indicated a reduction in the number of intramembrane particles; however, the terminal synthesizing complexes remained at all times. Treatment with 10 μM actinomycin D, when applied during the first hour of protoplast formation, irreversibly inhibits cellulose synthesis and terminal complex formation. De novo protein synthesis is required for cell wall regeneration by protoplasts. The data suggest that the structural subunits visualized in the terminal complex do not undergo significant turnover, but that there may exist an essential proteinaceous component of cellulose synthesis which must be continually renewed.
The effect of Calcofluor white on the formation of the cell wall was studied in yeast and mycelial cells ofCandida albicans using uv microscopy, conventional electron microscopy (including qualitative and stereologic analyses), and freeze-fracture. The uv microscopy of semithin sections showed that abnormal deposition of chitin occurs in both yeast and mycelial cells. Ultrathin sections revealed that abnormal chitin deposition in yeast cells results in a wall thickening which protrudes into the cytoplasm. The thickening appeared in the region of the yeast cell wall where formation of the bud would take place. In mycelial cells, one or more bulges were observed, mainly located at the position of the septum. In freeze-fracture replicas, abnormally deposited wall material from the bulge displayed a rougher appearance than that normally deposited. Moreover, no significant differences with respect to intramembranous particles were observed between plasma membranes of control and Calcofluor-treated cells. In contrast, stereologic analysis on ultrathin sections of control and Calcofluor-treated cells showed significant differences in the volume of the cell wall between these cell populations. These results support the previously reported hypothesis that Calcofluor white interferes with deposition of chitin but not with its synthesis.
The successful culture of isolated protoplasts of tobacco in the presence of a vital fluorescence stain, Calcofluor White (CW), is reported. The method can be used in both liquid culture and with cells immobilized in agar. Wall formation seems to start at distinct points and can be observed as early as one hour after protoplast isolation. The material either spreads from these points over the entire surface, or the synthesizing apparatus moves in a manner which allows the formation of a continuous layer. The crystallization of the newly synthesized material seems to be hindered by CW, indicating that a rigid cell wall is not a prerequisite for cell division. On the other hand, no cytokinesis occurred unless the protoplasts were surrounded by material showing CW-fluorescence.
The mechanism of cell elongation in five red algae, Griffithsia pacifica Kylin, G. tenuis C. Agardh, G. globulifera Harvey, Antithamnion kylinii Gardner, and Callithamnion sp. was studied using Calcofluor White ST as a vital, fluorescent cell-wall stain. In each alga elongation of intercalary shoot cells occurs primarily by the localized addition of new cell-wall material rather than by extension of pre-existing cell wall. Cell extension is localized in narrow bands in the lateral walls of a cell; there may be one or two bands per cell and these may be located at the top or bottom of the lateral wall. The number and location of bands of elongation are constant within a species but vary from species to species. Cell walls of elongating intercalary cells of each of these algae are essentially isotropic, indicating a net random orientation of cell-wall microfibrils.
An optical brightener Calcofluor White M2R New has been used to stain cell walls of higher plants. It can he used either as a vital stain for intact plants or for hand sections and plastic-embedded thin sections. Walls are brilliantly fluorescent while most cytoplasmic components are normally unstained. The brightener binds strongly to cellulose, carborylated polysaccbaridcs, and callose. Staining for 20 sec to 2 min in a 0.01% solution of the brightener is preferred for most purposes. © 1975 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.
The fluorescent brightener, Calcofluor White ST, prevents the in vivo assembly of crystalline cellulose microfibrils and ribbons
by Acetobacter xylinum. In the presence of more than 0.01 percent Calcofluor, Acetobacter continues to synthesize high-molecular-weight
beta-1,4 glucans. X-ray crystallography shows that the altered product exhibits no detectable crystallinity in the wet state,
but upon drying it changes into crystalline cellulose I. Calcofluor alters cellulose crystallization by hydrogen bonding with
glucan chains. Synthesis of this altered product is reversible and can be monitored with fluorescence and electron microscopy.
Use of Calcofluor has made it possible to separate the processes of polymerization and crystallization leading to the biogenesis
of cellulose microfibrils, and has suggested that crystallization occurs by a cell-directed. self-assembly process in Acetobacter
xylinum.
Cellulose produced by Acetobacter xylinum was experimentally modified during its biosynthesis. In the presence of fluorescent brightening agents, such as Calcofluor
White M2R or Tinopal LPW, nonmicrofibrillar sheets of cellulose were synthesized by the bacteria. These sheets could then
be converted to fibrils by washing with distilled water. Possible mechanisms for these modifications of cellulose assembly
are disscussed.
Experimental induction of altered nonmi-Hahne, Wall formation and cell division in fluorescent labelled plant protoplasts
- R M Brown
- Jr
- C Haigler
- K G Cooper
- W Herth
- F Hoffman
Brown, R. M., Jr., Haigler, C. and Cooper, K. 1982. Experimental induction of altered nonmi-Hahne, G., Herth, W. and Hoffman, F. 1983. Wall formation and cell division in fluorescent labelled plant protoplasts. Protoplasma 115: 21 7-221.
198 1. Polysaccharides of the seaweeds: In: The Biology ofScaweeds
- E L Mccandless
McCandless, E. L. 198 1. Polysaccharides of the seaweeds: In: The Biology ofScaweeds, Lobban, C. S. and Wynne, M. J., eds. University of California Press, Berkeley. pp. 559-588.
Accumulation of cytoplasmic vesicles in cell walls during cell modification in Chaetomorpha moniligera
- K Okuda
- S Mizuta
Okuda, K. and Mizuta, S. 1987. Accumulation of cytoplasmic vesicles in cell walls during cell modification in Chaetomorpha moniligera. Jpn. J. Phycol. 35: 113-120.
Development in red algae: elongation and cell fusion
- S D Waaland
Waaland, S. D. 1980. Development in red algae: elongation and cell fusion. In: Handbook of Phycological Methods, Gantt, E., ed. Cambridge University Press, Cambridge. pp. 85-93.
Experimental induction of altered nonmicrofibrillar cellulose
- R M Brown
- Jr
- C Haigler
- K Cooper
Polysaccharides of the seaweeds The Biology of Seaweeds, C
- E L S Mccandless
- M J Lobban
- Wynne
- Starr R. C.
Seasonal variations in growth in the red alga Chondrus crispus on the Atlantic French coasts. I. A new approach by fluorescent labelling
- T Chopin
- Floc
Abnormal formation of Candida albican walls produced by Calcofluor white: an ultrastructural and stereologic study
- H Rico
- R Muragal
- R Sentandreu
- Itoh T.