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Alcohol extracts of marine algae (Rhodophyceae, Phaeophyceae and Chlorophyceae) were screened for their effect on central nervous system. Of 69 species investigated 8 appeared biologically active, 6 being CNS stimulant and two depressant, sites and dates of collection are given.
Phlorotannins often have various toxic effects against a large number of organisms. From the ethyl acetate fraction of the ethanolic extract of the brown alga Cystophora torulosa 33 phlorotannins were obtained. Twenty of them are described in this report: phlorethols and fuhalols, and fucophlorethols and hydroxyfucophlorethols. Seven of them were isolated for the first time. New phlorotannins bearing additional hydroxy groups belong to the hydroxyfucophlorethols. NMR- and MS-data were used for structural elucidation. Several of the substances described for C. torulosa occur in Sargassum spinuligerum as well.
A single quadrupole high performance liquid chromatography electrospray mass spectrometry system with a variable fragmentor voltage facility was used in the positive ion mode for simultaneous recording of elemental and molecular mass spectral data for arsenic compounds. The method was applicable to the seven organoarsenic compounds tested: four arsenic-containing carbohydrates (arsenosugars), a quaternary arsonium compound (arsenobetaine), dimethylarsinic acid, and dimethylarsinoylacetic acid. It was not suitable for the two inorganic arsenic species arsenite and arsenate. In the case of arsenosugars, qualifying ion data for a characteristic common fragment (m/z 237) was also simultaneously obtained. The method was used to identify and quantify the major arsenosugars in crude extracts of two brown algae.
DNA was immobilized within alginate matrix using an external or an internal calcium source, and then membrane coated with chitosan or poly-L-lysine. Membrane thickness increased with decreasing polymer molecular weight and increasing degree of deacetylation (chitosan). Beads were exposed to a 31,000 molecular weight nuclease to determine the levels of DNA protection offered by different membrane and matrix combinations. Almost total hydrolysis of DNA was observed in alginate beads following nuclease exposure. Less than 1% of total double-stranded DNA remained unhydrolyzed within chitosan- or poly-L-lysine-coated beads, corresponding with an increase in DNA residuals (i.e. double- and single-stranded DNA, polynucleotides, bases). Chitosan membranes did not offer sufficient DNA protection from DNase diffusion since all of the double-stranded DNA was hydrolyzed after 40 min of exposure. Both chitosan and poly-L-lysine membranes reduced the permeability of alginate beads, shown by enhanced retention of DNA residuals after DNase exposure. The highest level of DNA protection within freshly prepared beads was obtained with high molecular weight (197,100) poly-L-lysine membranes coated on beads formed using an external calcium source, where over 80% of the double-stranded DNA remained after 40 min of DNase exposure. Lyophilization and rehydration of DNA beads also reduced permeability to nucleases, resulted in DS-DNA recoveries of 60% for chitosan-coated, 90% for poly-L-lysine-coated, and 95% for uncoated alginate beads.
From an ethyl acetate fraction of the brown alga Cystophora retroflexa several halogenated phlorotannins were isolated. Most of the compounds are derivatives of diphlorethol penta-acetate and triphlorethol-A hepta-acetate. The majority turned out to be chlorinated and/or brominated. Only one iodinated substance, 2-iodophloroglucinol triacetate, was isolated. The structure of this derivative and the following compounds have been characterized previously: 2([D])-bromodiphlorethol penta-acetate, 3([A1])-bromodiphlorethol penta-acetate, 4([D])-bromo-diphlorethol penta-acetate, 4([D])-chlorodiphlorethol penta-acetate, 3([A1])-chlorotriphlorethol-A hepta-acetate, 4([D])-bromotriphlorethol-A hepta-acetate and 4([D])-chlorobisfucopentaphlorethol-A nonadeca-acetate. Ten halogenated phlorethols and two chlorinated fucophlorethols are described for the first time and characterized as their acetates: 2([B])-bromotriphlorethol-A hepta-acetate, 2([D])-bromotriphlorethol-A hepta-acetate, 2([B]), 2([D])-dibromotriphlorethol-A hepta-acetate, 3([A1]), 5([A1])-dichlorotriphlorethol-A hepta-acetate, 3([A1]), 4([D])-dichlorotriphlorethol-A hepta-acetate, 3([A1])-chloro-4([D])-bromotriphlorethol-A hepta-acetate. 2([B]), 4([D])-dichlorotriphlorethol-A hepta-acetate, 2([D]), 3([A1])-dibromotriphlorethol-A hepta-acetate, 3([A1])-bromo-2([D])-chlorotriphlorethol-A hepta-acetate, 2([D])-bromotetraphlorethol-C nona-acetate, 4([D])-chlorofucotriphlorethol-B dodeca-acetate and 4([D])-chlorobisfucotetraphlorethol-A heptadeca-acetate.
Freeze-dried alginate sponge crosslinked with covalent bonds was developed in our laboratory and has been demonstrated to enhance peripheral nerve regeneration. In this study, we examined spinal cord repair using alginate sponge in infant rats. On postnatal day 8-12, the spinal cord was transversely resected at Th7-Th8 to produce a 2-mm gap. The gap was filled with alginate sponge in the alginate group. For the control group, the gap was left empty. In the alginate group, the recovery of evoked electromyogram and sensory-evoked potentials 6 weeks after surgery indicated that elongation of axons could establish electrophysiologically functional projections through the gap. A histological study revealed that myelinated and unmyelinated axons, surrounded by a perineurial-like structure, had elongated across the gap. An immunohistochemical examination revealed that elongation of astrocytic processes and/or migration of astrocytes into the alginate sponge was induced, whereas astrocyte gliosis was reduced at the interface between the implanted alginate and the host spinal cord, compared with the control group. However, a horseradish peroxidase tracing study revealed ascending and descending fibers had also elongated into the gap and reentered the other stump of the transected spinal cord beyond the gap. These results suggest that alginate might provide a permissive microenvironment for elongation of spinal cord axons.
Thylakoid membranes from several brown algae have been fragmented with the non-ionic detergent, Triton X-100. Three intrinsic chlorophyll-protein complexes with different pigment compositions have been isolated by sucrose density gradient centrifugation. Brown algae contain the photosystem 1 reaction-centre complex, a P700-chlorophyll a-protein which has similar spectroscopic and chemical properties to those of higher plants. This complex represents about 10--20% of the total chlorophyll in all species; the Acrocarpia paniculata complex has a chlorophyll/P700 ratio of 38. Two main light-harvesting complexes have also been isolated, which have properties unique to brown algae. The heavier of these, an orange fraction, is a fucoxanthin-chlorophyll a/c-protein; this complex contains most of the fucoxanthin and has only chlorophyll c2. The other, a green fraction, is a chlorophyll a/c-protein enriched in violaxanthin. Neither of these complexes possesses detectable photosystem 1 or photosystem 2 activities. Both of these complexes efficiently transfer light energy to chlorophyll a, indicating that the molecular arrangement of their pigments is similar to that in vivo. Differential extraction of thylakoid membranes indicates that the P700-chlorophyll a-protein is the complex most firmly embedded in the membrane, but the fucoxanthin-chlorophyll a/c-protein is the least firmly bound. We suggest that the fucoxanthin complex is the most variable component of the photosynthetic unit of brown algal chloroplasts.
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Previous work has demonstrated that dynamic actin arrays are important for axis establishment and polar growth in the fucoid zygote, Silvetia compressa. Transitions between these arrays are mediated by depolymerization of an existing array and polymerization of a new array. To begin to understand how polymerization of new arrays might be regulated, we investigated the role of the highly conserved, actin-nucleating, Actin-related protein 2/3 (Arp2/3) complex. Arp2, a subunit of the complex, was cloned and peptide antibodies were raised to the C-terminal domain. In immunolocalization studies of polarizing zygotes, actin and Arp2 colocalized around the nucleus and in a patch at the rhizoid pole. In germinated zygotes, a cone of Arp2 and actin extended from the nucleus to the subapex. Within the rhizoid tip, three structural zones were observed in the majority of zygotes: the extreme apex was devoid of label, the subapex was enriched for Arp2, and further back both actin and Arp2 were present. This zonation suggests that actin nucleation occurs at the leading edge of the cone, in the Arp2-enriched region. In two sets of experiments, we showed that tip zonation is important for growth. First, pharmacological treatments that disrupted Arp2/actin zonation arrested tip growth. Second, changes in the direction of tip growth during negative phototropism were preceded by a reorientation of the zonation in accordance with the new growth direction. This work represents the first investigation of Arp2/3 complex localization in tip-growing algal cells.
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Bromoperoxidases were investigated by protein blotting after polyacrylamide gel electrophoresis. While the denatured proteins bound to nitrocellulose, the native enzymes did not. Instead, they could be transferred successfully to DEAE-cellulose. Procedures for immunostaining and glycoprotein detection with concanavalin A on DEAE-cellulose are described. The results indicate that binding of native proteins to nitrocellulose can not necessarily be assumed. DEAE-cellulose is suitable both to investigate this phenomenon or as a substitute for nitrocellulose in blotting of native proteins.
Chronic exposure of the skin to ultraviolet B (UVB) radiation induces oxidative stress, which plays a crucial role in the induction of skin cancer. In this study, the effect of dietary feeding and topical application of brown algae polyphenols on UVB radiation-induced skin carcinogenesis in SKH-1 mice was investigated. SKH-1 hairless mice were randomly divided into 9 groups, including control, UVB control and treatment groups. They were treated orally (0.1% and 0.5% with AIN-76 diet, w/w) and topically (3 and 6 mg/0.2 ml of vehicle) with brown algae polyphenols and irradiated with UVB for 26 weeks. Dietary feeding (0.1% and 0.5%) of brown algae polyphenols significantly reduced tumor multiplicity (45% and 56%) and tumor volume (54% and 65%), and topical administration (3 and 6 mg) significantly decreased tumor multiplicity (60% and 46%) and tumor volume (66% and 57%), respectively, per tumor-bearing mouse. Dietary feeding and topical administration of the polyphenols also inhibited tumor incidence by 6% and 21%, respectively, but the results were not significant. Dietary and topical administration of the polyphenols markedly inhibited cyclooxygenase-2 activity and cell proliferation. These observations show that brown algae polyphenols have an antiphotocarcinogenic effect which may be associated with the prevention of UVB-induced oxidative stress, inflammation, and cell proliferation in the skin.
A case of clostridial endomyometritis and sepsis necessitating total abdominal hysterectomy which occurred 12 hours following abortion induced with intraamniotic administration of prostaglandin F2 alpha and laminaria tent insertion is discussed. Cultures from cervical, blood, and surgical specimens all yielded Clostridium perfringens. Intrauterine contamination with this microorganism most likely followed the insertion of laminaria tents through the cervical os, which was colonized with C. perfringens. Since C. perfringens may be present in the microflora of the lower female genital tract, great care must be taken to cleanse this area prior to intracervical laminaria tent insertion.
Reducing medical complications resulting from induced abortion by identifying the safest and most appropriate procedures(s) for each gestational age is the purpose of this study. Data on all women who had induced abortions at all hospitals in the State of Hawaii where such procedures were performed between March 11, 1970, when the new abortion law went into effect, and June 30, 1974 were analyzed. Study findings show that if the abortion procedure with the least risk of complications at each length of gestation were selected a reduction in the complication rate of nearly 30% could result.
We investigated the cytoprotective effect of phloroglucinol, which was isolated from Ecklonia cava (brown alga), against oxidative stress induced cell damage in Chinese hamster lung fibroblast (V79-4) cells. Phloroglucinol was found to scavenge 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydrogen peroxide (H(2)O(2)), hydroxy radical, intracellular reactive oxygen species (ROS), and thus prevented lipid peroxidation. As a result, phloroglucinol reduced H(2)O(2) induced apoptotic cells formation in V79-4 cells. In addition, phloroglucinol inhibited cell damage induced by serum starvation and radiation through scavenging ROS. Phloroglucinol increased the catalase activity and its protein expression. In addition, catalase inhibitor abolished the protective effect of phloroglucinol from H(2)O(2) induced cell damage. Furthermore, phloroglucinol increased phosphorylation of extracellular signal regulated kinase (ERK). Taken together, the results suggest that phloroglucinol protects V79-4 cells against oxidative damage by enhancing the cellular catalase activity and modulating ERK signal pathway.
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Algae from cold water (Canada) and warm water (China) were analyzed for their total lipid content, and for their fatty acid (FA) composition and content. The major findings are that FA from Canadian algae are generally richer in polyunsaturated FA (PUFA), with a higher n-3/n-6 FA ratio, and a higher degree of total unsaturation. The 18 C, 4 double bonds FA (18 : 4 stearidonic acid, morotic acid as synonym) was detected in greater amounts in cold water samples. The high levels of total PUFA, and especially of n-3 FA in Canadian algae, suggests their possible utilizations for nutritional purposes.