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1.
In this study, effective gamete concentrations, egg viability, and fertilization volumes were evaluated for Haliotis midae (L.). Sperm concentrations between 5?×?103 and 5?×?104?mL?1 (p?>?0.05) consistently resulted in high hatch-out rates (96?±?1%). At concentrations higher than 5?×?105?mL?1, hatch-out rates decreased to 69?±?7% (p??1 resulted in high fertilization rates, with 50?eggs?mL?1 being the ideal concentration for fertilization in H. midae. Egg viability was consistently high up to 100?min post-spawning, with a decrease in hatch-out success, when eggs were fertilized 120?min post-spawning. Fertilization volumes did not affect successful hatch-out. The results from this study can be implemented by South African abalone farms to increase hatch-out rates and subsequent culture. It can also be used as basis for the development of fertilization protocols in other marine invertebrate species.  相似文献   

2.
Microwave‐assisted extraction was employed to extract polyphenols from the leaf of Magnolia kwangsiensis Figlar & Noot . The yield of polyphenols was 2.44±0.02 % under the optimal conditions of RSM: acetone concentration of 70 %, ratio of solvent to material of 21 mL?g?1 and extraction time of 16 min. The antioxidant activities were evaluated in terms of total antioxidant ability, reducing power, DPPH ? and ? OH scavenging activity. Results showed the polyphenols presented potential antioxidant activities, especially the stronger scavenging activity on ? OH. In term of ? OH scavenging activity, the IC50 value of NKA‐9 purification was 0.335 mg mL?1, equivalent to 35.23 % of VC. The IC50 values of crude extract and ethyl acetate extract were 0.580 and 0.828 mg mL?1, equivalent to 60.99 % and 87.07 % of VC. Results indicated that M. kwangsiensis leaf polyphenols present potential antioxidant activities that make it beneficial for human health by preventing or reducing oxidative damage.  相似文献   

3.
The objective of this study was to evaluate the production of pectinase by an isolated strain of Penicillium brasilianum in a bioreactor and to consider its potential for industrial applications (i.e. fruit juice). The optimization of production was achieved through experimental design. The maximum exo-polygalacturonase (Exo-PG) production in the bioreactor was 53.8?U mL?1 under the conditions of 180?rpm, an aeration rate of 1.5 vvm, 30?°C, pHinitial of 5.5, 5?×?106 spores mL?1, 32?g L?1 pectin, 10?g L?1 of yeast extract and 0.5?g L?1 magnesium sulfate and bioproduction for 36?h. The production of Exo-PG in the bioreactor was 1.3 times higher than that obtained in shake flasks, with aeration (1.5 vvm) and agitation (180?rpm) control. The crude enzyme complex, beyond the pectinolytic activity of Exo-PG (53.8?U mL?1), also contained activity pectin methylesterase (6.0?U mL?1) and pectin lyase (6.61?U mL?1). At a crude enzyme complex with a concentration of 0.5% (v/v), viscosity of peach juice was reduced by 11.66%, turbidity was reduced by 13.71% and clarification was increased by 26.92%. Based on the present results, we can conclude that the new strain of isolated P. brasilianum produced high amounts of pectinases in a bioreactor with mechanical agitation, and has the potential to be applied to in the clarification of juices.  相似文献   

4.
The ethanolic leaf extract (TZP) of Zuccagnia punctata, its ethereal fraction (Eet), 2′,4′‐dihydroxychalcone (DC), 2′,4′‐dihydroxy‐3′‐methoxychalcone (DMC) and 7‐hydroxy‐3′,4′‐dimethoxyflavone (HF) were evaluated as fungicide seed protectants on corn. Microdilution assays on a set of Fusarium strains showed minimum inhibitory concentrations (MICs) of 400–800 μg mL?1 (TZP), 50–100 μg mL?1 (Eet), 25–50 μg mL?1 (DC), 50–100 μg mL?1 (DMC) and 200–400 μg mL?1 (HF), with minimum fungicidal concentration (MFC)/MIC = 1. Suspensions of TZP, Eet, DC and DMC at MIC × 20 incorporated to the grains at rates of 1920, 240, 120 and 240 mg dry matter kg?1 of grain, respectively, increased the elongation of the primary roots (24–44%) and the number of seminal roots (44–50%). TZP also increased the number of secondary roots. HF was phytotoxic. Suspensions of TZP, Eet, DC and DMC suppressed the endogenous grain mycoflora at levels similar to those recorded for a thiram + carbendazim‐based fungicide. Grains treated with TZP (1920 mg kg?1), Eet (240 mg kg?1), DC (120 mg kg?1) and DMC (240 mg kg?1) stimulated the growth of the seedling root system both because of fungal suppression and hormetic effects in greenhouse curative and preventive assays against Fusarium verticillioides on a sand/soil substrate. Eet and its chalcones also reduced the severity of seedling blight more than the thiram + carbendazim‐based fungicide in preventive assays and led to the same disease severity observed for the fungicide treatment in the curative assays. Our results show that Eet and its chalcones not only were effective seed protectants against F. verticillioides and other seedborne fungi, but also improved the early performance of maize seedlings.  相似文献   

5.
Abstract

Growth and production of carotenoid in three Dunaliella species (Dunaliella salina (Dunal) Teodoresco, Dunaliella bardawil Ben-Amotz & Avron and Dunaliella sp.) were investigated using flat-plate photobioreactors in outdoor conditions with two optical paths (3?cm and 5?cm). The experiment was conducted in duplicate and lasted four weeks during which light intensity, temperature, pH and optical density were checked daily. The pigment production (total carotenoid and chlorophyll a) was monitored every two days. To induce an additional stress besides temperature and light intensity, two different salt concentrations were used, i.e. 6% and 8% NaCl. The highest growth in all treatment groups was noticed for Dunaliella sp. followed by D. bardawil and D. salina. D. salina produced a higher content of carotenoid concentrations corresponding to 5?cm/8% and 5?cm/6% groups; 779.102?±?0.434?μg.mL?1 and 694.326?±?0.098?μg.mL?1 were registered at the end of the experiment. The same species had also greater content of β-carotene.  相似文献   

6.
Sheep breeding has suffered economic losses due to parasitism by gastrointestinal nematodes, particularly Haemonchus contortus. The use of natural products, specifically Tagetes patula, has been suggested as an alternative method of combatting this issue. Chemical analyses of the extracts of this species described in the literature report the presence of important classes of secondary metabolites such as thiophenes, flavonoids, alkaloids, and benzofurans, some of which were identified and isolated in this study. The aim of this work was to test the effect of the essential oil (EO) and the ethanolic extract of the aerial parts (TpEtOH) of T. patula on eggs and larvae of H. contortus, through an egg hatch test (EHT) and a larval development test (LDT). In the EHT, the EO showed 100% inhibition at 0.75 mg mL?1 (LC50 = 0.0780 mg mL?1), and the TpEtOH showed 100% inhibition at 100 mg mL?1 (LC50 = 12.8 mg mL?1). In the LDT, the EO showed 100% inhibition at 0.375 mg mL?1 (LC50 = 0.0400 mg mL?1), and the TpEtOH showed 100% inhibition at 1.56 mg mL?1 (LC50 = 0.340 mg mL?1). Compared to available literature data, the results presented here suggest that the crude extracts of T. patula have substantial potential for controlling this nematode by interrupting its life cycle and/or preventing it from reaching the infective stage.  相似文献   

7.
The potential bio-herbicide Plectosporium alismatis produces drying and UV tolerant micro-sclerotia-like structures named aggregates, effective against the weed Alisma plantago-aquatica. In this study, we evaluated (i) optimal liquid culture conditions that supported the high dry weight, conidia and aggregate yields and (ii) stress-tolerance and effectiveness of aggregates. Using a full factorial 25 design, we studied the impact of agitation (A), glucose concentration (B), Tween 80 concentration (C), malt extract concentration (D), and inoculum density (E), on P. alismatis growth yields. The inoculum density (E), the agitation rate (A), and 3-factor interactions involving E and/or A had significant effects on aggregate yields (average 213 aggregates mL?1; main effect of E: +112.87; main effect of A: ?74.81), but no significant effect on conidial yields and dry weight. The agitation was maintained at 100?rpm and increasing numbers of conidia were inoculated into the culture media. Maximal aggregate yields (3.6?×?103 aggregates mL?1) were obtained with an initial conidial density of 4?×?106 conidia mL?1. While freshly-harvested, dried and/or UV exposed aggregates germinated at high rates (respectively: 100%; 99%; 76%; 85%), sporogenesis significantly decreased after stress exposure. In bioassays using leaf discs of A. plantago-aquatica, chlorosis and/or necrosis was observed after 8 days incubation, regardless of whether aggregates had been exposed to desiccation and/or UV-radiations prior to application on leaf discs. These data provide a cultural protocol for the production of high numbers of UV and drying resistant aggregates effective against weed species of Alismatacae.  相似文献   

8.
Abstract

A novel tannase and gallic acid-producing Penicillium rolfsii (CCMB 714) was isolated from cocoa leaves from the South of Bahia. The influence of nutritional sources and the simultaneous effect of parameters involved in the fermentation process were available. Tannase (9.97 U?mL?1) and gallic acid (9?mg mL?1) production were obtained in 48?h by submerged fermentation in non-optimized conditions. Among the carbon sources, tested gallic acid and tannic acid showed the highest tannase production (p<.05) when compared with methyl gallate and glucose. After optimization using the temperature and tannic acid concentration as variables with the Central Compound Rotational Design (CCRD), the maximal tannase production (25.6?U mL?1) was obtained at 29.8?°C and 12.7%, respectively, which represents an increase of 2.56 times in relation to the initial activity. The parameters optimized for the maximum production of gallic acid (21.51?mg mL?1) were 30?°C and 10% tannic acid. P. rolfsii CCMB 714 is a new strain with a high tannase and gallic acid production and the gallic acid produced is very important, mainly for its applications in the food and pharmaceutical industry.  相似文献   

9.
Aronia melanocarpa berries are abundant in polyphenolic compounds. After juice production, the pomace of pressed berries still contains a substantial amount of polyphenolic compounds. For efficient utilization of A. melanocarpa berries and the enhancement of polyphenolic compound yields in Aronia melanocarpa pomace (AMP), total phenolics (TP) and total flavonoids (TF) from AMP were extracted, using ultrasound-assisted aqueous two-phase system (UAE-ATPS) extraction method. First, the influences of ammonium sulfate concentration, ethanol–water ratio, ultrasonic time, and ultrasonic power on TP and TF yields were investigated. On this basis, process variables such as ammonium sulfate concentration (0.30–0.35?g?mL?1), ethanol–water ratio (0.6–0.8), ultrasonic time (40–60?min), and ultrasonic power (175–225?W) were further optimized by implementing Box–Benhnken design with response surface methodology. The experimental results showed that optimal extraction conditions of TP from AMP were as follows: ammonium sulfate concentration of 0.324?g?mL?1, ethanol–water ratio of 0.69, ultrasonic time of 52?min, and ultrasonic power of 200?W. Meanwhile, ammonium sulfate concentration of 0.320?g?mL?1, ethanol–water ratio of 0.71, ultrasonic time of 50?min, and ultrasonic power of 200?W were determined as optimum extraction conditions of TF in AMP. Experimental validation was performed, where TP and TF yields reached 68.15?±?1.04 and 11.67?±?0.63?mg?g?1, respectively. Close agreement was found between experimental and predicted values. Overall, the present results demonstrated that ultrasound-assisted aqueous two-phase system extraction method was successfully used to extract total phenolics and flavonoids in A. melanocarpa pomace.  相似文献   

10.
Evaluation of antioxidant capacities of green microalgae   总被引:2,自引:0,他引:2  
Three strains of green microalgae, Chlorococcum sp.C53, Chlorella sp. E53, and Chlorella sp.ED53 were studied for their antioxidant activities. Crude extracts of these microalgae in hot water and in ethanol were examined for their total phenolic contents and for their antioxidant capacities. In order to determine their phenolic contents, the Folin–Ciocalteu method was used. As for the determination of their antioxidant capacities, four different assays were used: (1) total antioxidant capacity determination; (2) DPPH radical scavenging assay; (3) ferrous ion chelating ability assay; and (4) inhibition of lipid peroxidation (using thiobarbituric acid reactive substance). For all the strains we have studied, their ethanolic extract showed more antioxidant activities than their hot water extract. Categorically, the ethanolic extract of Chlorella sp.E53 exhibited both the highest total phenolic content of 35.5?±?0.14 mg gallic acid equivalent (GAE) g?1 dry weight and the highest DPPH radical scavenging of 68.18?±?0.38 % at 1.4 mg mL?1 (IC50 0.81 mg mL?1), whereas Chlorella sp.ED53 showed both the highest ferrous ion chelation activity of 42.78?±?1.48 % at 1 mg mL?1 (IC50 1.23 mg mL?1) and the highest inhibition of lipid peroxidation of 87.96?±?0.59 % at 4 mg mL?1. This high level of inhibition is comparable to 94.42?±?1.39 % of butylated hydroxytoluene, a commercial synthetic antioxidant, at the same concentration.  相似文献   

11.
Root-knot nematode, Meloidogyne javanica, is a major problem confronting greenhouse’s productions, field crops, vegetables, grapevines and almond rootstocks in Kermanshah province, Iran. Nematicides are not affordable to control this nematode. In the search for alternatives to chemicals control of nematodes, this research has dealt with nematicidal effects of crude herbal extracts on the root-knot nematodes. This study aimed to evaluate the effect of 21 endemic and exotic herbal extracts belong to 12 families of flowering plants in comparison with chicken manure and chemical nematicide (Temik) to control root-knot nematodes in in vitro conditions. The nematodes were pured and mass multiplied on tomato in the soil at greenhouse conditions. In order to study the effect of herbal extracts on mortality of second-stage juveniles (J2), a 6?mL of each extract was poured in sterilised Petri dish and 54?±?4 juveniles were added. Distilled water was used as control and treatments replicated four times and incubated at ambient temperature. The LC50 value of each extract was determined by assessing the mortality of juveniles (in the range of 5–95%) after 24, 48 and 72 h. Comparison between LC50 value of the extracts indicated that Cinnamomum zeylanicum and Eugenia caryophillata are the most effective crude extracts on the mortality of juveniles and they were 15.4 and 17.9?mg?mL?1, respectively. Meanwhile, the extract of tobacco, ferulago, garlic, eucalyptus, persan lilac, rattle, oliveria, licorice, russian knapweed, turnsole, sicilian sumac and chicken manure did not have any antinematode activity against fresh second-stage juveniles of the root-knot nematode.  相似文献   

12.
We optimized a spectrophotometric method for measuring ribulose-l,5-bisphosphate carboxylase oxygenase (Rubisco) activity in crude extracts of the kelp Laminaria saccharina Lamour. Activity exhibited a decline during the assays, such that rates determined over a 10-min period were only 70% of activity during the first minute. Activity was significantly enhanced by addition of HCO3? to the extraction buffer and was stable for at least 4 h. Highest activities were determined using small extract loads (1–2.5 mg fresh weight·mL?1 of assay mixture); extract loads of 10 mg·mL?1caused a 25% decrease in activity. Rubisco activities determined for individual kelp plants using the spectrophotometric method were significantly correlated with total protein and gross photo synthetic capacity (Pmax) and were 1.5–2 times higher than Pmax. Low Rubisco activities relative to photosynthetic rates reported in many previous studies of macroalgae and microalgae may have resulted at least partly from underestimation of enzyme activity by radiometric assays using relatively large volumes of un-activated crude extract and assay periods longer than 1 min.  相似文献   

13.
The biomass and concentration of bioactive quinone methide-type diterpenes in hairy roots of Salvia austriaca were determined and compared with levels of these metabolites in roots of field-grown plants. The cultures were maintained in shake flasks and a nutrient sprinkle bioreactor. Diterpene production was more efficient in the shake flask root culture than the bioreactor one. Biomass and diterpene production within the shake flask culture was evaluated using Schenk and Hildebrandt (SH), Gamborg (B5), and woody plant medium (WPM), with both full- and half-strength macro and micronutrient concentrations (1/2 SH, 1/2 B5, and 1/2 WPM). Among the tested media, SH medium proved to be most effective for biomass and diterpene production. In this medium, the transformed roots accumulated the levels of taxodone (3.89?mg?g?1 DW; equivalent to 63.3?mg?L?1), taxodione (1.15?mg?g?1 DW; equivalent to 17.4?mg?L?1), 15-deoxy-fuerstione (2.15?mg?g?1 DW; equivalent to 32.5?mg?L?1), and 7-(2′-oxohexyl)-taxodione (0.076?mg?g?1 DW; equivalent to 1.1?mg?L?1). Three diterpenes were also detected in the roots of S. austriaca intact plants, but their concentrations were lower than those in hairy root culture. No 7-(2′-oxohexyl)-taxodione was found in the roots of field-grown plants. The hairy roots were able to maintain high metabolite levels even for 6 years of cultivation. Taxodone, taxodione, 15-deoxy-fuerstione, and 7-(2′-oxohexyl)-taxodione were tested for in vitro activity against Trypanosoma brucei rhodesiense, T. cruzi, and Plasmodium falciparum and their cytotoxicity was determined using L6 cells. Among these compounds, taxodione was the most active against T. brucei rhodesiense [IC50?=?0.05?µM with high selectivity, selectivity index (SI)?=?38]. Taxodione was found to inhibit the growth of P. falciparum and T. cruzi by 50% at respective concentrations of 1.9 and 7.1?µM (SI values of 1.0 and 0.27). Other diterpenoids demonstrated weaker activity against tested parasites (IC50 values ranging from 0.62 to 194.7?µM) and lower selectivity (SI value ranged from 0.4 to 5.0).  相似文献   

14.
A high‐performance liquid chromatography (HPLC) method was established to detect Xeljanz enantiomers in active pharmaceutical ingredients (APIs) and tablets. The separation was achieved on a Chiralpak IC column using a mobile phase of hexane‐ethanol‐diethylamine (65:35:0.1, v/v). The detection wavelength was 289 nm. The peak areas and the enantiomer concentrations in the range of 0.15–2.25 μg?mL?1 were in high linearity, with correlation coefficients higher than 0.999. The recoveries were 86.44% at the concentrations of 7.5, 18.75, and 37.5 μg?mL?1. The limit of detection (LOD) and limit of quantification (LOQ) were 0.042 and 0.14 μg?mL?1, respectively. This HPLC method is suitable for detecting the enantiomers of Xeljanz in its APIs and tablets. Chirality 27:235–238, 2015. © 2014 Wiley Periodicals, Inc.  相似文献   

15.
Evaluation of protectant ability of Newbouldia laevis (Seem.) extracts against infestation by Callosobruchus maculatus in cowpea, Vigna unguiculata L. (Walp.) was carried out in the laboratory at ambient temperature of 28?±?2?°C and 70?±?5% relative humidity. Extracts from wood ash, leaf, stem and root bark were tested at different concentrations of 0, 1, 2, 3, 4 and 5%. One hundred per cent mortality of adult beetles was achieved at all concentrations within 72?h of treatment with extracts except in wood ash at 1% concentration, but they were significantly different (p?<?0.05) from the controls. All the extracts were still able to cause high beetle mortality after one, two and three months of cowpea storage at high concentrations (4 and 5%) except wood ash, although there was a slight decrease in mortality during the period of storage. All the extracts significantly (p?<?0.05) reduced oviposition and adult emergence of C. maculatus when compared with the controls although the reduction was higher at 5% concentration than others. Adult beetle emergence was completely prevented at higher concentrations (4 and 5%) except in wood ash. Both oviposition and adult emergence increased during the months of storage probably because of the slight reduction in the effectiveness of the extracts. The root bark extract was much more effective in reducing oviposition and adult emergence than others throughout the period of storage. The plant extracts of N. laevis was able to protect the cowpea seeds from damage and prevent weight loss. Cowpea seed damage and weight loss was significantly more (p?<?0.05) in the controls than other for the three-month duration probably because of the more adult emergence. The extracts from N. laevis did not adversely affect the germination of the protected seeds and seed germination ranged from 86.7 to 100%. It has been shown in this study that the extracts of N. laevis were effective against C. maculatus in cowpea although the root bark extract seemed to be the most effective while the wood ash extract was least effective. Their effectiveness, however, slightly decreased during the period of storage. N. laevis could be incorporated into pest management of stored cowpeas since the products are ecologically safe.  相似文献   

16.
The entomopathogenic fungus Aschersonia aleyrodis (Webber) is a promising fungal species against whiteflies. In this work, the pathogenicity of A. aleyrodis isolate Aa005 against MEAM1 Bemisia tabaci (Gennadius) was evaluated under laboratory and greenhouse conditions. The bioassay results indicated that the percentage of larval mortalities was concentration and age dependent. A. aleyrodis showed high pathogenicity against second and third instars and pupae with LC50 values of 7.93?×?106, 1.08?×?107, and 1.56?×?107?conidia?mL?1, respectively. The median lethal time (LT50) was lower (4.60 days) for second instars and was the highest (6.17 days) for pupae when inoculated with a concentration of 1?×?107?conidia?mL?1. Weekly sampling of immatures showed that the per cent mortality caused by A. aleyrodis at a conidial concentration of 1?×?107?conidia?mL?1 was 71.21% in small nymphs, 69.31% in large nymphs and 53.36% in pupae. The dispersion index (DI) and Lloyd’s Index of Patchiness (LIP) values indicated that the infected immatures had a tendency to aggregate. The study demonstrated that A. aleyrodis isolate A005 is an effective biocontrol agent for B. tabaci control under laboratory and greenhouse conditions.  相似文献   

17.
The efficacy of clove oil as an anaesthetic and its effects on blood parameters in Nile perch Lates niloticus were evaluated in 2010. Clove oil concentrations of 49.3, 73.9 and 98.5?mg l?1 induced anaesthesia in <3?min, while the average recovery time from anaesthesia was 11?min 22 s. The optimal oil clove oil concentration was 49.3?mg l?1, inducing anaesthesia in 4?min 33 s, with recovery in 3?min 31 s. No stress response was elicited. Clove oil at a concentration of 24.6?mg l?1 was an effective sedative, whereas a concentration of 49.3?mg l?1 was sufficient for measuring fish and stripping gametes. A concentration of 73.9?mg l?1 induced anaesthesia within 4?min and fish recovered in 10?min. Therefore, clove oil was an effective anaesthetic and sedative for the handling of Nile perch within a mass range of 0.4–12?kg fish?1.  相似文献   

18.
Capsule Mediterranean Great Tits showed a marked increase in levels of circulating carotenoids during moult and autumn.

Aims To study seasonal variation in plasma carotenoid content during a whole annual cycle for Great Tits Parus major inhabiting a Mediterranean woodland.

Methods We used a sample of 71 adult male Great Tits captured in NE Spain during a whole year. Data were organized into four seasons (winter, breeding, moult and autumn). We sampled blood to extract plasma. Carotenoid plasma concentrations were analysed by High-performance liquid chromatography (HPLC).

Results Lutein and zeaxanthin content varied seasonally, with a marked increase in levels during moult and autumn. Within the moulting period, levels increased gradually as the season progressed. This pattern differed significantly from that previously described in northern European populations, where high values appear mainly in the breeding season. Carotenoid concentrations (lutein: 1.2?±?0.25, zeaxanthin: 0.07?±?0.03?µg mL?1) were also lower than in northern Europe.

Conclusion Mediterranean Great Tits show a very different pattern of circulating carotenoids and lower levels than northern European populations. The increasing pattern of carotenoid availability found within the moulting period raises the need to control for the effect of sampling date when analysing data on carotenoid concentrations at different times of year.  相似文献   

19.
Abstract

A sand hydroponic experiment with different concentrations of 0, 5, 10, 20, 40?mg L?1 Cd was used to study the growth and physiological response of Hylotelephium spectabile (Boreau) H. Ohba. and its phytoextraction potential for Cd. The results showed that total plant biomass under 5?mg L?1 Cd treatment was slightly affected. The content of malondialdehyde (MDA) in leaf exposed to Cd was higher, and the POD and CAT activity exhibited a positive response to the low level of Cd addition (5?mg·L?1). The photosynthesis pigments were slightly inhibited, and the ultrastructure of chloroplast remained intact after treatment with 10?mg L?1 Cd. The maximum leaf Cd content (603?mg·kg?1) was found in 5?mg L?1 Cd treatment, then decreased with the Cd level increased. The maximum Cd content in the shoots far exceeds the threshold level (100?mg kg?1) for a Cd-hyperaccumulator plant with the value of translocation factor (TFshoot/root) for Cd reaching up to 5.62. In conclusion, H. spectabile showed normal growth and physiological response and high shoot Cd accumulation under 5?mg L?1 Cd stress, which made it to be a good candidate for phytoextraction of low-level Cd polluted environment.  相似文献   

20.
Alga-bacterium relationships between a Bacillus cereus strain L7 and Anabaena flos-aquae were studied based on the effects of the algicidal substances on algal growth indicators such as enzyme activity and membrane lipid peroxidation. When exposed to algae-lytic products at a concentration of 0.05?mg?mL?1, chlorophyll a (Chla), protein and phycobiliprotein contents increased significantly (p?<?0.05); superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and malondialdehyde (MDA) concentrations increased slightly to stimulate the algae growth. When exposed to algae-lytic products at a concentration of 0.5?mg?mL?1, algae growth and composition were inhibited. Chla, protein and phycobiliprotein concentrations decreased significantly (p?<?0.05 for protein, p?<?0.01 for Chla and phycobiliprotein). MDA concentrations increased significantly (p?<?0.05). POD and CAT activities increased by approximately six and three times, respectively, in 24?h compared with the control, then decreased to the initial level in 4?days. Algae-lytic products have not only inhibition but also stimulation effects on A. flos-aquae. Such effects are associated with antioxidative/oxidative reactions as indicated by the biomarkers SOD, POD, CAT, and MDA.  相似文献   

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