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1.
不受欢迎的生物多样性:香港的外来植物物种 总被引:44,自引:2,他引:44
香港早在19世纪中叶开始就有外来植物入侵的记录,迄今为止,已发现多达238种已归化的外来或怀疑为外来的植物,其中又以薇甘菊(Mikania micrantha)、五爪金龙(Ipomoea cairica)、假臭草(Eupatorium catarium)、大黍(Panicum maximum)等最常见,外来植物最常见于受人为干扰的生境,例如荒废农田及路旁等,而较少在天然林地生境及贫瘠的灌草丛中发现,外来植物的对本地生态系统的影响主要局限于低地生境,它们常形成单优种群,减少了生境及贫瘠的灌草丛中发现,外来植物对本地生态系统的影响主要局限于低地生境,它们常形成单优种群,减少少了生境及动植物的多样性,外来动物对香港原生植物影响最大的是于20世纪70年代入侵的松树线虫(Bur-saphelenchus xylophilus)。外来的脊椎动物也有可能对香港的植物被演替产生影响,目前香港的外来植物当中,有些在大陆较少分布或没有记录,作为华南最大的港口,香港对外来物种的引入扮演着重要的角色,因此制定控制外来种在香港及华南地区的引入及传播的政策及措施非常重要。 相似文献
2.
Mchedlishvili NI Omiadze NT Gulua LK Sadunishvili TA Zamtaradze RK Abutidze MO Bendeliani EG Kvesitadze GI 《Prikladnaia biokhimiia i mikrobiologiia》2005,41(2):165-170
Stabilities of phenol oxidase and peroxidase from tea plant (Camellia sinensis L.) clone Kolkhida leaves, apple (Malus domestica L.) cultivar Kekhura fruits, walnut (Juglans regia L.) green pericarp, and horseradish (Armoracia lapathifolia Gilib) roots were studied using different storage temperature modes and storage duration. It was demonstrated that both enzymes retained residual activities (approximately 10%) upon 20-min incubation at 80 degrees C. Phenol oxidases from tea, walnut, and, especially, apple, as well as tea peroxidase were stable during storage. A technology for treatment of plant oxidases was proposed, based on the use of a natural inhibitor phenol oxidase and peroxidase, isolated from tea leaves, which solving the problem of residual activities of these enzymes, arising during pasteurization and storage of beverages and juices. It was demonstrated that browning of apple juice during pasteurization and beer turbidity during storage could be efficiently prevented using the natural inhibitor of these enzymes. 相似文献
3.
N. T. Omiadze N. I. Mchedlishvili N. G. Pruidze L. K. Gulua M. O. Abutidze K. Sh. Akhvlediani E. G. Kvesitadze V. R. Aplakov 《Applied Biochemistry and Microbiology》2007,43(1):21-24
The possibility to regulate phenoloxidase activity with sulfur dioxide was studied. It was found that this compound is a potent inhibitor of phenoloxidase of the reversible and mixed type. The inhibitory effect of sulfur dioxide on phenoloxidase provided grounds for a new biotechnological approach to the production of instant green tea. This approach allows increasing the yield of the extractive and the proportion of phenolics in the extractive, thereby improving the organoleptic quality of the product. 相似文献
4.
N. I. Mchedlishvili G. N. Pruidze N. T. Omiadze R. V. Zukhbaya 《Applied Biochemistry and Microbiology》2000,36(2):115-118
Phenol oxidase (EC 1.14.18.1) from the microscopic fungusMycelia sterilia IBR 35219/2 was immobilized using glutaraldehyde on macroporous silica carriers. The enzyme immobilized on amino-Silochrome
SKh-2 or aminopropyl-Silochrome 350/80 exhibited maximum activity. Soluble and immobilized phenol oxidases were compared.
Compared to the soluble enzyme, the activity of which was optimum at pH 5.5, immobilized phenol oxidase exhibited optimum
activity under slightly more acidic conditions (pH 5.2). Immobilization considerably increased enzyme stability. Both soluble
and immobilized forms of phenol oxidase fromM. sterilia IBR 35 219/2 catalyze oxidative conversion of phenolic compounds of green tea extract. 相似文献
5.
N. T. Omiadze N. I. Mchedlishvili J. N. Rodrigez-Lopez M. O. Abutidze T. A. Sadunishvili N. G. Pruidze 《Applied Biochemistry and Microbiology》2014,50(4):394-397
We determined the molecular weight and some properties of multiple forms of phenol oxidase from tea leaves and four other perennial plants. It was shown that multiple high- and low-molecular forms of phenol oxidase differed in substrate specificity. Low-molecular forms of the enzyme mostly demonstrated hydroxylase activity, while high-molecular forms showed catechol oxidase activity. It was revealed that the withering stage of black tea production is accompanied by the formation of only high-molecular forms of phenol oxidase, which possess catechol oxidase activity crucial for the procurement of oxidative reactions and the quality of the product. 相似文献
6.
Nucleotide polymorphism in the acidic chitinase locus (ChiA) region of the wild plant Arabidopsis thaliana 总被引:3,自引:0,他引:3
To investigate DNA variation in natural plant populations, a 1.8-kb region
of the acidic chitinase locus (ChiA)was analyzed for 17 ecotypes of
Arabidopsis thaliana sampled worldwide and 3 Arabis species in Japan. As in
the Adh region, dimorphism was detected throughout the investigated ChiA
region, suggesting the possibility that dimorphic DNA variation exists in
the entire nuclear genome of A. thaliana. The ChiA region was divided into
two blocks by an intragenic recombination between two parental sequence
types, which diverged 7.4 MYA under the assumption that nucleotide mutation
rate per site per year is mu = 10(- 9). Nucleotide diversity in the entire
ChiA region was 0.0104. Tajima's test was significantly negative for both
nucleotide and indel variations, which was manifested as an excess of
unique polymorphisms. However, the level and pattern of polymorphism in the
ChiA region were inconsistent with simple theoretical explanations. The HKA
test detected no difference in the levels of intra- and interspecific
variations between the ChiA and Adh regions. In the ChiA coding region, no
difference in the patterns of synonymous and replacement variation was
found in intra- and interspecific comparisons by the MK test. Although it
was difficult to determine the exact genetic mechanism acting on the ChA
locus, these results suggested that the ChA locus region was under the same
genetic mechanism before and after the establishment of A. thaliana as a
species.
相似文献
7.
Omiadze NT Mchedlishvili NI Pruidze NG Gulua LK Abutidze MO Akhvlediani KSh Kvesitadze EG Aplakov VP 《Prikladnaia biokhimiia i mikrobiologiia》2007,43(1):26-30
The possibility to regulate phenoloxidase activity with sulfur dioxide was studied. It was found that this compound is a potent inhibitor of phenoloxidase of the reversible and mixed type. The inhibitory effect of sulfur dioxide on phenoloxidase provided grounds for a new biotechnological approach to the production of instant green tea. This approach allows increasing the yield of the extractive and the proportion of phenolics in the extractive, thereby improving the organoleptic quality of the product. 相似文献
8.
Mchedlishvili NI Pruidze GN Omiadze NT Zukhbaia RV 《Prikladnaia biokhimiia i mikrobiologiia》2000,36(2):138-142
Phenol oxidase (EC 1.14.18.1) from the microscopic fungus Mycelia sterilia IBR 35219/2 was immobilized using glutaraldehyde on macroporous silica carriers. The enzyme immobilized on amino-Silochrome SKh-2 or aminopropyl-Silochrome 350/80 exhibited maximum activity. Soluble and immobilized phenol oxidases were compared. Compared to the soluble enzyme, the activity of which was optimum at pH 5.5, immobilized phenol oxidase exhibited optimum activity under slightly more acidic conditions (pH 5.2). Immobilization considerably increased the enzyme stability. Both soluble and immobilized forms of phenol oxidase from M. sterilia IBR 35219/2 catalyze oxidative conversion of phenolic compounds of the green tea extract. 相似文献
9.
Omiadze NT Pruidze GN Mchedlishvili NI Gulua LK 《Ukrainski? biokhimicheski? zhurnal》2000,72(3):38-43
The intracellular localization and some properties of monophenol monooxygenase (MPMO) from fresh tea leaves have been studied. It has been demonstrated that MPMO activity is located in cytosole and chloroplasts. These two forms have different properties. Molecular weights of cytosole and chloroplasts MPMO are 41 and 28 kD respectively. The chloroplasts and cytosole forms of MPMO reveal maximum activity at pH 5.3 and 7.1 respectively. 相似文献