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1.
Andreazza R Okeke BC Pieniz S Brandelli A Lambais MR Camargo FA 《Biological trace element research》2011,143(2):1182-1192
Environmental copper contamination is a serious human health problem. Copper reductase is produced by microorganisms to facilitate
copper uptake by ATPases into the cells increasing copper biosorption. This study assessed the reduction of Cu(II) by cell-free
extracts of a highly copper-resistant bacterium, Pseudomonas sp. strain NA, isolated from vineyard soil contaminated with copper. Both intact cells and cell-free extract of Pseudomonas sp. strain NA displayed substantial reduction of Cu(II). Intact cells reduced more then 80 mg L−1 of Cu(II) from medium amended with 200 mg L−1 of copper after 24 h of incubation. Cell-free extract of the isolate reduced more than 65% of the Cu(II) at initial copper
concentration of 200 mg L−1 after 24 h. Soluble protein production was high at 72 h of incubation at 100 mg L−1 of copper, with more then 60 μg L−1 of total soluble protein in cell-free extract recorded. Cu(II) reduction by isolate NA was increased when copper concentration
increased for both intact cells and cell-free extract. Results indicate that Pseudomonas sp. strain NA produces copper reductase enzyme as the key mechanism of copper biotransformation. 相似文献
2.
Filtrates from crushed Moringa oleifera seeds were tested for their effects on growth and Photosystem II efficiency of the common bloom-forming cyanobacterium Microcystis aeruginosa. M. aeruginosa populations exhibited good growth in controls and treatments with 4- and 8-mg crushed Moringa seeds per liter, having similar growth rates of 0.50 (±0.01) per day. In exposures of 20- to 160-mg crushed Moringa seeds L−1, growth rates were negative and on average −0.23 (±0.05) .day−1. Presumably, in the higher doses of 20- to 160-mg crushed seeds per liter, the cyanobacteria died, which was supported by
a rapid drop in the Photosystem II efficiency (ΦPSII), while the ΦPSII was high and unaffected in 0, 4, and 8 mg L−1. High-density populations of M. aeruginosa (chlorophyll-a concentrations of ∼270 μg L−1) were reduced to very low levels within 2 weeks of exposure to ≥80-mg crushed seeds per liter. At the highest dosage of 160 mg L−1, the ΦPSII dropped to zero rapidly and remained nil during the course of the experiment (14 days). Hence, under laboratory conditions,
a complete wipeout of the bloom could be achieved. This is the first study that yielded evidence for cyanobactericidal activity
of filtrate from crushed Moringa seeds, suggesting that Moringa seed extracts might have a potential as an effect-oriented measure lessening cyanobacterial nuisance. 相似文献
3.
Yan Gong Hong-Nong Chou Chi-dao Tu Xi Liu Jiantong Liu Lirong Song 《Journal of applied phycology》2009,21(2):225-231
Arsenic pollution and eutrophication are both prominent issues in the aquaculture ponds of Taiwan. It is important to study
the effects of arsenic on algal growth and toxin production in order to assess the ecological risk of arsenic pollution, or
at least to understand naturally occurring ponds. The sensitivity of algae to arsenate has often been linked to the structural
similarities between arsenate and phosphate. Thus, in this study we examined the effects of arsenate (10−8 to 10−4 M) on Microcystis aeruginosa TY-1 isolated from Taiwan, under two phosphate regimes. The present study showed that M. aeruginosa TY-1 was arsenate tolerant up to 10−4 M, and that this tolerance was not affected by extracellular phosphate. However, it seems that extracellular phosphate contributed
to microcystin production and leakage by M. aeruginosa in response to arsenate. Under normal phosphate conditions, total toxin yields after arsenate treatment followed a typical
inverted U-shape hormesis, with a peak value of 2.25 ± 0.06 mg L−1 in the presence of 10−7 M arsenate, whereas 10−8 to 10−6 M arsenate increased leakage of ∼75% microcystin. Under phosphate starvation, total toxin yields were not affected by arsenate,
while 10−6 and 10−5 M arsenate stimulated microcystin leakage. It is suggested that arsenate may play a role in the process of microcystin biosynthesis
and excretion. Given the arsenic concentrations in aquaculture ponds in Taiwan, arsenate favors survival of toxic M. aeruginosa in such ponds, and arsenate-stimulated microcystin production and leakage may have an impact on the food chain. 相似文献
4.
Juan Wang Wen-Yuan Gao Jian Zhang Tao Huang Tian-Tian Wen Lu-Qi Huang 《Acta Physiologiae Plantarum》2011,33(3):861-866
Lactoalbumin hydrolysate (LH) at 100 mg L−1 with methyl jasmonate (MJ) at 2 mg L−1 synergistically stimulated ginsenoside accumulation in Panax quinquefolium cells compared with 100 mg L−1 LH. Combination elicitors led to higher ginsenoside productivity (45.93 mg L−1) than single treatment of 100 mg L−1 LH (31.37 mg L−1). This present result will be helpful in providing a tool for enhancing the productivity of ginsenoside by Panax quinquefolium cell cultures on a commercial scale. 相似文献
5.
Sarfraz Hussain Muhammad Arshad Baby Shaharoona Muhammad Saleem Azeem Khalid 《World journal of microbiology & biotechnology》2009,25(5):853-858
The rates of biodegradation of endosulfan by P. aeruginosa were determined with different initial endosulfan concentrations (10, 50, 100, 150, 200 and 250 mg l−1) and different growth linked kinetic models were fitted at these concentrations. At 10 mg endosulfan l−1, Monod no growth model was well fitted. Monod with growth model described the biodegradation pattern at an initial concentration
of 50, 100 and 150 mg endosulfan l−1. Significant increases of P. aeruginosa MN2B14 density in broth culture during incubation further support this result. Conversely, zero order kinetic model was well
fitted into the biodegradation data if initial endosulfan concentration was ≥200 mg endosulfan l−1. The kinetics of endosulfan biodegradation by P. aeruginosa MN2B14 in liquid broth was highly dependent upon its initial concentration. The results of this study could be employed for
predicting the persistence of endosulfan in water environment containing P. aeruginosa as an endosulfan degrading bacterium. 相似文献
6.
Microcystis aeruginosa isolated in 2005 from the shallow eutrophic Lake Chao (Anhui, China) was investigated in terms of growth parameters and microcystin
production under varying nutrient concentrations (P, N) and pH values (abiotic factors) as well as under the influence of
spent medium of the non-toxic cyanobacterium Synechocystis sp. (biotic factors). Stimulating effects on growth were observed at the alkaline pH value (10.5), whereas toxin production
was significantly increased under phosphate-P limitation (0.6 mg L−1 medium). Within a broad range of nitrate–N concentrations (41.2–247.2 mg L−1 medium), no significant influence on cell growth and microcystin production was observed; however, N-starvation resulted
in a typical decrease of growth and toxicity. In addition, cryopreservation of M. aeruginosa evidenced the decrease of toxin production by time-dependent exposure with the cryoprotectant dimethyl sulfoxide under thawing
conditions without affecting the growth of the cyanobacterial cells. 相似文献
7.
Cell cultures of Cayratia trifolia (Vitaceae), a tropical lianas, were maintained in Murashige and Skoog’s medium containing 0.25 mg l−1 NAA, 0.2 mg l−1 kinetin and casein hydrolysate 250 mg l−1. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin), which on elicitation by any of 500 μM salicylic acid,
100 μM methyl jasmonate, 500 μM ethrel and 500 mg l−1 yeast extract, added on the 7th day, were enhanced by 3- to 6-fold (5–11 mg l−1) by the 15th day. 相似文献
8.
The role of different growth regulators in callus induction, shoot regeneration, floral induction and chlorophyll content
of the obligatory parasitic plant Cuscuta
reflexa has been studied. Callus development was excellent from the nodal part of the shoot explants in modified Murashige and Skoog
(MMS) media supplemented with 2 mg L−1 benzyl adenine (MMS1c). Supplementation of 2 mg L−1 naphthalene acetic acid (NAA) along with MMS1c (MMS2c) was responsible for estimable shoot induction and development in callus.
2,4-Dichloro acetic acid (2,4-D) played a crucial role in the floral induction of C. reflexa in vitro. MMS supplemented with 2 mg L−1 NAA and 2 mg L−1 2,4-D (MMS3b) supported floral induction after shooting in vitro. MMS supplemented with 3 mg L−1 2,4-D (MMS4a) rapidly induced flower directly from the stem explants without showing any elongation of shoot. MMS1c along
with MMS3b (MMS5a) showed callus proliferation followed by shoot elongation and floral induction. In vitro MMS5a grown plants
show a sharp increase in the chlorophyll contents. Cytokinin treatment further increases the chlorophyll level of the plant. 相似文献
9.
Qi Xiang Zhang Yu Sun Heng Kang Hu Bei Chen Chun Tao Hong Hai Peng Guo Yin Hui Pan Bing Song Zheng 《In vitro cellular & developmental biology. Plant》2012,48(1):50-57
Miscanthus sinensis (Poaceae) is a typical perennial giant grass of East Asia. Due to its high photosynthetic efficiency, low input requirements,
and high biomass production, M. sinensis shows outstanding potential as a biofuel feedstock. However, the lack of an efficient tissue culture system may limit its
utilization potential. Different explants of M. sinensis were evaluated to develop an efficient tissue culture system. Shoot apices from in vitro-germinated seedling explants were tested for adventitious bud proliferation. The highest level of proliferation (multiplication
coefficient 6.69) was obtained when shoot apices were cultured on Murashige and Skoog (MS) medium supplemented with 1.0 mg L−1 6-benzyladenine (BA), 2.0 mg L−1 kinetin, 0.05 mg L−1 α-naphthalene acetic acid (NAA), 3% sucrose, and 0.8% agar. The highest rooting percentage (95.4%) was obtained when adventitious
buds were cultured on half-strength MS medium supplemented with 0.2 mg L−1 NAA, 3% sucrose, and 0.8% agar. Significant differences were found in the formation of embryogenic callus among different
explant types. The embryogenic callus derived from epicotyls had the highest regeneration capacity when cultured on a medium
supplemented with 2.0 mg L−1 2,4-dichlorophenoxyacetic acid, 0.5 mg L−1 BA, and 0.1 mg L−1 thiamine. Under these conditions, the callus induction percentage was 82%. 相似文献
10.
Somatic embryogenesis and plant regeneration in two wild cotton species belong to G genome 总被引:1,自引:0,他引:1
Shu-Feng Yan Qiao Zhang Jing-Er Wang Yu-Qiang Sun M. K. Daud Shui-Jin Zhu 《In vitro cellular & developmental biology. Plant》2010,46(3):298-305
The present work describes the plant regeneration via somatic embryogenesis in two wild cotton species belonging to G genome:
Gossypium nelsonii Fryx and Gossypium australe F Muell. The role of plant hormones and carbohydrates was also evaluated for somatic embryogenesis and somatic embryo development.
Normal plants were obtained from G. nelsonii Fryx; abnormal plants and somatic embryos were obtained from G. australe F Muell. The best medium for callus induction for these G genome wild cotton species was MSB5 supplemented with 0.1 mg L−1 KT and 0.1 mg L−1 2,4-D. For embryogenic callus proliferation, the best medium used was MSB5 supplemented with 0.2 mg L−1 KT and 0.5 mg L−1 IBA. The medium MSB5 supplemented with 0.15 mg L−1 KT and 0.5 mg L−1 NAA was used successfully for root initiation and plant growth. In addition, adding CuSO4 and AgNO3 in the callus-inducing and proliferation medium resulted in a number of somatic embryos. Glucose and maltose, the carbon
sources in somatic culture, were used for callus induction, but maltose worked even better than glucose for proliferation
of embryogenic callus and development of somatic embryos. 相似文献
11.
Juan Wang Wenyuan Gao Jian Zhang Tao Huang Tiantian Wen Liming Zhang Luqi Huang 《Plant Growth Regulation》2011,63(3):217-223
In this article, ginsenosides and polysaccharide contents in suspension cells and native roots of Panax quinquefolium L. were studied. In order to enhance the contents of ginsenosides and polysaccharide in P. quinquefolium suspension cells, we tested the effects of lactoalbumin hydrolysate on the growth of P. quinquefolium suspension cell, synthesis of ginsenosides and polysaccharide in flask and bioreactor. In flask culture, cells growth ratio
was significantly enhanced by the addition of lower concentration of lactoalbumin hydrolysate. Addition of 100 mg L−1 lactoalbumin hydrolysate significantly enhanced the contents of total saponins (5.44 mg g−1 DW) and the contents were 3.89-fold over the control group. Addition of lactoalbumin hydrolysate significantly promoted the
accumulation of polysaccharide, except 200 mg L−1 lactoalbumin hydrolysate. The highest total saponins yield (36.72 mg L−1 DW) and polysaccharide yield (0.83 g L−1 DW) were obtained at 100 mg L−1 lactoalbumin hydrolysate. In a 5-L stirred tank bioreactor, the highest contents of total saponins and TRb group ginsenosides
were achieved on day 26, while the effect of lactoalbumin hydrolysate on the contents of TRg group ginsenosides were insignificant.
This result suggests that lactoalbumin hydrolysate might have triggered the enzyme activities for the synthesis of TRb group
ginsenosides. Overall, the highest total saponins yield (31.37 mg L−1 DW) and polysaccharide yield (1.618 g L−1 DW) were obtained on day 26 and day 24 respectively and the polysaccharide yield was 1.95-fold higher than the shake flask
culture (0.83 g L−1 DW). These results provided theoretical reference for two-stage culture in suspension cells of P. quinquefolium in bioreactor. 相似文献
12.
The cell cultures of Cayratia trifolia (Vitaceae) a tropical lianas, were maintained in Murashige and Skoog’s medium containing 0.25 mg l−1 naphthalene acetic acid, 0.2 mg l−1 kinetin and 250 mg l−1 casein hydrolysate. Cell suspension cultures of C. trifolia accumulate stilbenes (piceid, resveratrol, viniferin, ampelopsin) which on addition of 0.1–0.5 mg l−1 morphactin in the medium containing naphthalene acetic acid and kinetin declined. Morphactin or 2 isopentenyl adenine alone
at 0.1 mg l−1 concentration enhanced stilbenes which on combination markedly enhanced the yield to ~5 mg l−1 at 15th day. 相似文献
13.
Michael Pescheck Marco Antonio Mirata Bianca Brauer Ulrich Krings Ralf Günter Berger Jens Schrader 《Journal of industrial microbiology & biotechnology》2009,36(6):827-836
A closed gas loop bioprocess was developed to improve fungal biotransformation of monoterpenes. By circulating monoterpene-saturated
process gas, the evaporative loss of the volatile precursor from the medium during the biotransformation was avoided. Penicillium solitum, isolated from kiwi, turned out to be highly tolerant towards monoterpenes and to convert α-pinene to a range of products
including verbenone, a valuable aroma compound. The gas loop was mandatory to reproduce the production of 35 mg L−1 verbenone obtained in shake flasks and also in the bioreactor. Penicillium digitatum DSM 62840 regioselectively converted (+)-limonene to the aroma compound α-terpineol, but shake flask cultures revealed a
pronounced growth inhibition when initial concentrations exceeded 1.9 mM. In the bioreactor, toxic effects on P. digitatum during biotransformation were alleviated by starting a sequential feeding of non-toxic limonene portions after a preceding
growth phase. Closing the precursor-saturated gas loop during the biotransformation allowed for an additional replenishment
of limonene via the gas phase. The gas loop system led to a maximum α-terpineol concentration of 1,009 mg L−1 and an average productivity of 8–9 mg L−1 h−1 which represents a doubling of the respective values previously reported. Furthermore, a molar conversion yield of up to
63% was achieved.
M. Pescheck and M. A. Mirata have contributed equally to this work. 相似文献
14.
Zamalloa C De Vrieze J Boon N Verstraete W 《Applied microbiology and biotechnology》2012,93(2):859-869
The biomass of industrially grown Phaeodactylum tricornutum was subjected in a novel way to bio-methanation at 33°C, i.e., in an anaerobic membrane bioreactor (AnMBR) at a hydraulic
retention time of 2.5 days, at solid retention times of 20 to 10 days and at loading rates in the range of 2.6–5.9 g biomass-COD L−1 day−1 with membrane fluxes ranging from 1 to 0.8 L m−2 h−1. The total COD recovered as biogas was in the order of 52%. The input suspension was converted to a clear effluent rich in
total ammonium nitrogen (546 mg TAN L−1) and phosphate (141 mg PO4-P L−1) usable as liquid fertilizer. The microbial community richness, dynamics, and organization in the reactor were interpreted
using the microbial resource management approach. The AnMBR communities were found to be moderate in species richness and
low in dynamics and community organization relative to UASB and conventional CSTR sludges. Quantitative polymerase chain reaction
analysis revealed that Methanosaeta sp. was the dominant acetoclastic methanogen species followed by Methanosarcina sp. This work demonstrated that the use of AnMBR for the digestion of algal biomass is possible. The fact that some 50% of
the organic matter is not liquefied means that the algal particulates in the digestate constitute a considerable fraction
which should be valorized properly, for instance as slow release organic fertilizer. Overall, 1 kg of algae dry matter (DM)
could be valorized in the form of biogas (€2.07), N and P in the effluent (€0.02) and N and P in the digestate (€0.04), thus
totaling about €2.13 per kilogram algae DM. 相似文献
15.
Ethrel treatment enhanced isoflavonoids accumulation in cell suspension cultures of Pueraria tuberosa, a woody legume 总被引:1,自引:0,他引:1
The cell cultures of Pueraria tuberosa, a perennial leguminous lianas, were maintained in modified MS medium (KNO3 475 mg l−1, thiamine 1 mg l−1, biotin 1 mg l−1, calcium pantothenate 1 mg l−1) containing 0.1 mg l−1 2,4,5-trichloroacetic acid and 0.1 mg l−1 kinetin. Isoflavonoids (puerarin, genistin, daidzein, genistein) accumulation in cell suspension cultures was increased by
14-fold to ~12 mg l−1 after 48 h of adding 100 μM ethrel. Ethrel inhibitors (silver nitrate and silver thiosulfate) completely inhibited this effect
in the presence of ethrel and isoflavonoids were not detected in the spent medium. The increase was dose dependent and can
be explored to trigger high yield of isoflavonoids production. 相似文献
16.
N. Selvaraj S. Kasthurirengan A. Vasudevan M. Manickavasagam C. W. Choi A. Ganapathi 《In vitro cellular & developmental biology. Plant》2010,46(4):329-337
Efficient Agrobacterium tumefaciens-mediated transformation and a higher recovery of transformed plants of cucumber cv. Poinsett76 were achieved via direct organogenesis
from cotyledon explants. Stable transformants were obtained by inoculating explants with A. tumefaciens strains EHA105 or LBA4404, both harboring the binary vector pME508, which contains the neomycin phosphotransferase II (nptII) and phosphinothricin resistance genes (bar) conferring resistance to kanamycin and PPT, respectively, as selectable markers and the sgfp-tyg gene for the green fluorescent protein (GFP) as a visual marker driven by the constitutive CaMV35S promoter in the presence
of acetosyringone (50 μM). Transformed shoots were obtained on MS Murashige and Skoog (Plant Physiol. 15: 473–497, 1962) medium supplemented with 1 mg L−1 benzyladenine (BA), 20 mg L−1
l-glutamine and 2 mg L−1 phosphinothricin (PPT) or 100 mg L−1 kanamycin. The regenerated shoots were examined in vivo using a hand-held long wave UV lamp for GFP expression. The GFP screening helped identify escapes and chimeric shoots at
regular intervals to increase the growth of transformed shoots on cotyledon explants. Elongation and rooting of putative transformants
were achieved on PPT (2 mg L−1) containing MS media with 0.5 mg L−1 gibberellic acid (GA3) and 0.6 mg L−1 indole butyric acid (IBA), respectively. PCR and Southern analyses confirmed the integration of the sgfp gene into the genome of T0 and the progenies. T1 segregation of transgenic progeny exhibited Mendelian inheritance of the transgene. The use of EHA105 resulted in 21% transformation
efficiency compared to 8.5% when LBA4404 was used. This higher rate was greatly facilitated by PPT selection coupled with
effective screening of transformants for GFP expression, thus making the protocol highly useful for the recovery of a higher
number of transgenic cucumber plants. 相似文献
17.
The green microalga Chlorella zofingiensis can produce the ketocarotenoid astaxanthin under heterotrophic culture conditions. Here we report the growth-associated biosynthesis
of astaxanthin in this biotechnologically important alga. With glucose as sole carbon and energy source, C. zofinginesis grew fast in the dark with rapid exhaustion of nitrogen and carbon sources from media, leading to a high specific growth
rate (0.034 h−1). Cultures started at a cell concentration of about 3.4 × 109 cells l−1 reached, after 6 days, standing biomass values of 1.6 × 1011 cells or 8.5 g dry weight l−1. Surprisingly, the biosynthesis of astaxanthin was found to start at early exponential phase, independent of cessation of
cell division. A general trend was observed that the culture conditions benefiting cell growth also benefited astaxanthin
accumulation, indicating that astaxanthin was a growth-associated product in this alga. The maximum cell dry biomass and astaxanthin
yield were 11.75 g l−1 and 11.14 mg l−1 (about 1 mg g−1), simultaneously obtained in the fed-batch culture with a combined glucose–nitrate mixture addition, which were the highest
ever reported in dark-heterotrophic algal cultures. The possible reasons why dark-heterotrophic C. zofingiensis could produce astaxanthin during the course of cell growth were discussed. 相似文献
18.
Thiocyanate-degrading microbial co-culture was isolated from thiocyanate-contaminated site and tested for thiocyanate degradation
potential and thiocyanate-toxicity tolerance and identified as Klebsiella pneumoniae and Ralstonia sp. by 16S rDNA sequencing. The co-culture was able to degrade thiocyanate with degradation rate of 500 mg L−1d−1 at 2,500 mg L−1 thiocyanate concentration at pH 6.0 and 37oC following thiocyanate hydrolase pathway. The Haldane kinetic model elucidates
the growth and thiocyanate biodegradation kinetics of the co-culture with Ki value of 1,876 mg L−1. The thiocyanate biodegradation kinetics was not affected by the additional supply of glucose. The very high activities of
thiocyanate hydrolase, cyanide oxygenase, and cytochrome P-450 content during growth on thiocyanate were observed, showing
the induction mechanism. 相似文献
19.
Adeline Su Yien Ting Chuan Chun Choong 《World journal of microbiology & biotechnology》2009,25(8):1431-1437
In our study, we isolated the isolate Trichoderma SP2F1 from sediment samples from the Penchala River, heavily contaminated with effluents from nearby industrial areas. Qualitative
and quantitative screening using plate and broth assay, respectively, supplemented with various concentrations of Cu(II) showed
the isolate was able to tolerate 6 mM CuSO4, although growth was also detected in broths with 10 mM CuSO4. Trichoderma spp. was able to remove Cu(II) in aqueous solutions in both viable and non-viable cell forms. Bioaccumulation capacity of
viable SP2F1 cells removed 19.60 mg g−1 of Cu(II) after 168 h incubation, while the maximum Cu(II) biosorption capacity for non-viable SP2F1 cells was 28.75 mg g−1 of Cu(II). Results here showed that Trichoderma spp isolate SP2F1 has good potential for application in Cu(II) removal, can be used to treat sewage waste by applying either
in viable or non-viable cell forms. 相似文献
20.
Xiulin Wang Liangyu Gong Shengkang Liang Xiurong Han Chenjian Zhu Yanbin Li 《Harmful algae》2005,4(2):6377
The algicidal activity of the rhamnolipid biosurfactants (the mixture of Rha-Rha-C10-C10 and Rha-C10-C10) produced by Pseudomonas aeruginosa was investigated in the present paper. The results indicated that the biosurfactants had potential algicidal effects on the harmful algal bloom (HAB) species, Heterosigma akashiwo. The growth of H. akashiwo was strongly inhibited in medium containing rhamnolipids (0.4–3.0 mg L−1); moreover, the rhamnolipids showed strong lytic activity toward H. akashiwo at higher concentrations (≥4.0 mg L−1). In addition, the effects of the rhamnolipids on the growth of Gymnodinium sp. and Prorocentrum dentatum, another two kinds of HAB species, were also studied. Compared with the dramatic algicidal effect on H. akashiwo, the cells of P. dentatum were inhibited or lysed at higher concentrations (1.0–10.0 mg L−1), while the cells of Gymnodinium sp. were not suppressed with the same treatment, indicating the rhamnolipids had the potential for the selective control of HABs.Morphometric analysis at ultrastructural level by transmission electron micrographs indicated that the extent of ultrastructural damage of the alga was severe at high concentrations of rhamnolipids and during extended periods of contact. The first response occurred in the plasma membrane which partly disintegrated. The lack of membrane facilitated the rhamnolipid biosurfactants into the cells and allowed damage to other organelles, which resulted in the injury of chloroplast, vacuolization of mitochondria and deformation of the cristae, disruption of nuclear membrane and condensation of chromatin in nucleus, suggesting that the lytic activity of rhamnolipids was mainly due to their powerful surfactivity and their tendency to cohere on the surface of phospholipids bimolecular layer of the cells and further destroyed the layers, and then the structure of quasi-membrane configurations inside the cells was disintegrated, following by the irreversible damage to the ultrastructure and the loss of the function of organelles, consequently leading the cells to lyse. 相似文献