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| Mtolera, M.S.P.. |
| Glutamate dehydrogenases (GDH, EC 1.4.1.2-4) catalyse the entry of ammonium into the organic cycle via amination of a-ketoglutarate and its release via deamination of Lglutamate. NAD-GDH facilitates NAD-/NADP-dependent deamination while NADPH-GDH facilitates NADH-/NADPH-dependent amination reactions. In the study reported here, GDHs were extracted from the red alga Gracilaria sordida and purified 10- to 180-fold before examining their amination and deamination reaction properties. NAD-/NADP- and NADH-/ NADPH-dependent activities were the order of 11:1 and 1:1.8, respectively. The pH optima for amination and deamination were 8.2 and 8.4 under NADH- and NADPH- and 8.4 and 9 under NAD- and NADP- dependent activities, respectively. Whereas both NAD- and... |
| Tipo: Journal Contribution |
Palavras-chave: Algae; Red algae; Http://aims.fao.org/aos/agrovoc/c_13790. |
| Ano: 2003 |
URL: http://hdl.handle.net/1834/965 |
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| Pratap, H.B.; Mamboya, F.A.; Mtolera, M.S.P.; Björk, M.. |
| The effect of copper (Cu) on the daily growth rate (DGR) and photosynthetic efficiency (PE) of the brown macroalga Padina boergesenii was studied under controlled laboratory conditions. The DGR was measured as an increase in fresh weight while the PE was measured as the ratio of variable to maximal chlorophyll fluorescence (Fv/Fm). Padina boegesenii were exposed to 25, 50, 100 and 500mg Cu/l for 21 days. The DGR and PE of P. boergesenii decreased significantly with an increase in copper concentration in the growth media. This study shows that copper is acutely toxic to P. boergesenii at concentrations higher than 500mg Cu/l. Low concentration of copper is toxic to P. boergesenii after a prolonged exposure of 21 days. Similarly, exposure time has a... |
| Tipo: Proceedings Paper |
Palavras-chave: Copper; Algae. |
| Ano: 1999 |
URL: http://hdl.handle.net/1834/787 |
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| Oliveira, E.C.; Österlund, K.; Mtolera, M.S.P.. |
| This is a book about the macroscopic marine plants of Tanzania, namely the seaweeds or benthic macroscopic algae and the seagrasses, that are marine flowering plants. Having flourished in the 19th century and the beginning of the 20th century, taxonomic studies then became less popular and the emphasis of biological investigations turned to other aspects of biology. However, after realising how important the conservation of biodiversity is, we are now experiencing a new interest in a more naturalistic approach to biology. But today this “romantic” approach is often fuelled by extensive bioprospection, the search of new drugs and gene conservation for use in transgenic organisms of commercial value. This in itself could justify the production of a new book... |
| Tipo: Book |
Palavras-chave: Marine plants; Seaweed; Seagrass. |
| Ano: 2003 |
URL: http://hdl.handle.net/1834/795 |
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| Buriyo, A.S.; Mtolera, M.S.P.. |
| Seasonal effects on yield and quality of kappa-carrageenan from the red alga Hypnea musciformis were investigated in samples collected from natural populations in Oyster Bay, Dar es Salaam during June 1996–May 1997. The mean annual carrageenan yield, gel strength (after treatment with 0.1 M KCl) gelling and melting temperature (± standard deviation) were 25.24 ± 4.44 % dry weight, 171.72 ± 41.42 g/cm2, 54.66 ± 3.12 ºC and 68.62 ± 0.60 ºC, respectively. Carrageenan yield and quality (gel strength) during the SE and NE monsoon seasons were not significantly different (t = 0.55, p > 0.05) and (t = 1.91, p > 0.05), respectively. The reported carrageenan yield and gel strength values were, respectively, about 50% and 40% those of carrageenan from... |
| Tipo: Journal Contribution |
Palavras-chave: Mariculture; Algal blooms; Temperature; Algal blooms; Http://aims.fao.org/aos/agrovoc/c_32367. |
| Ano: 2004 |
URL: http://hdl.handle.net/1834/1089 |
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| Mtolera, M.S.P.. |
| The productivity of two species of red algae, namely Eucheuma denticulatum (Burman) Collins et Harvey and Kappaphycus alvarezii (Doty) Doty was investigated at Paje and Uroa, two sites in Zanzibar differing in seagrass cover. The growth rate (GR) of E. denticulatum in Paje (low seagrass cover) was 20–75% lower than in Uroa (high seagrass cover), depending on season. Growth of K. alvarezii in Paje was compromised by Polysiphonia spp. epiphytism. Manganese, iron, copper and zinc contents of both E. denticulatum and K. alvarezii from Paje were 35–99% lower than in E. denticulatum from Uroa. Culturing of epiphyte-infested or healthy K. alvarezii in seawater fortified with the mentioned minerals improved daily GR by 10–200 %. The effect of Cu, Zn and Mn in K.... |
| Tipo: Journal Contribution |
Palavras-chave: Eucheuma denticulatum; Kappaphycus alvarezii Algae culture Seagrass Epiphytes. |
| Ano: 2003 |
URL: http://hdl.handle.net/1834/1084 |
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| Mtolera, M.S.P.; Semesi, A.. |
| Many algae species have been shown to have bactericidal or bacteriostatic substances (Glombitza, I979;Michaneck, 1979; Caccamese et al., 1980; Fenical & Paul, 1984; Niang& Hung, 1984). The antibacterialagents found in the algae include amino acids, terpenoids, phlorotannins, acrylic acid, phenoliccompounds, steroids, halogenated ketones and alkanes, cyclic polysulphides and fatty acids. In a large numberof marine algae antimicrobial activities are attributed to the presence of acrylic acid. |
| Tipo: Book Section |
Palavras-chave: Algae resources; Bacteriology. |
| Ano: 1996 |
URL: http://hdl.handle.net/1834/469 |
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