DD250549A1 - SCREENING METHOD FOR THE CHARACTERIZATION AND SELECTION OF EFFECTORS - Google Patents

Abstract

The "screening method for the characterization and selection of effectors" serves to make pesticide research more effective. It pursues the goal of analyzing and carrying out, through a minimized test hierarchy and minimized evaluation modes, the partially substance-induced effects on the optical properties, the ion turnover and possibly the photosynthetic and / or respiratory gas turnover of algal suspensions cultured autotrophically and heterotrophically in two standardized test variants Comparative considerations of the absolute Wirkquantitaeten, the Wirkquantitaetsdifferenzen from both test variants and of relative Wirkbilder in which the growth parameters and / or inhibition parameters with each other as effect effect-effect effect curves are considered as a function of the dose and optionally further parameters typical statements on the specifics of the investigated effectors receive. By comparing such active parameters newly to be examined substances with corresponding data of well-studied commercially distributed drugs can be assigned by means of a Wirkdaten- and Wirkbildkartei, electronic data processing or other comparison methods, the potential active ingredients according to their shown active ingredient basic types. By agreement of the Wirkquantitaeten, effects of two active substances, etc., similar mechanisms of action, metabolism and commercial applications can be concluded.

Description

Field of application of the invention

The invention relates to a screening method for the characterization and selection of effectors by means of growth, ion conversion and gas turnover analysis of autotrophic and heterotrophic cell suspensions, which can be used for example in crop protection research.

Characteristic of the known technical solutions

The influence of chemical substances on biological processes can be tested in a variety of ways, with the use of microalgae suspensions becoming increasingly important as a test model.

According to DD-PS 94234 can be selected from a sample of chemicals those that affect the fundamental process of autotrophic cell growth, especially of microalgae suspensions, directly or indirectly. While these methods for cell growth analysis spectral colorimetric or nephelometric method or to determine the rate of increase electronic particle counting methods are proposed, the method goes DD-PS 227464, which is based on microalgae suspensions as a test object of analyzes of the substance-initiated influences of the pH values of the algal suspensions as a measure the effective quantities for the evaluation of the inhibitory effect of the effectors.

Further advances in drug discovery to better characterize effector efficiencies enable selection processes that analyze two or more microbial susceptible growth parameters in a single step and derive drug-specific information from the comparison of these potentially differentiated growth parameters.

Thus, in the methods DD-PS 200472, DD-PS 2111 26 and DD-PS 2141 46 for the selection of effectors or for their Wirkcharakterisierung influencing the optical properties of autotrophic or heterotrophic algal suspensions at least two different wavelengths (for example, 680nm and 750nm) used. In the method according to DD-PS 21 41 46 is additionally used to characterize the action properties of the effectors on a comparison of the influence of the optical properties in the autotrophic and the heterotrophic test variant.

Comparative similar statements allow the methods DD-PS 212985, DD-PS 21 3950 and DD-PS 213949. According to these methods, the characterization of the action properties of effectors by analyzing the influence of the photosynthetic and / or respiratory gas exchange processes autotrophic and / or heterotrophic microalgae suspensions in preferably one operation and comparisons of the analysis results. More far-reaching statements on the specifics allow procedures in which the substance-initiated influences of the optical properties and gas exchange rates autotrophic (DD-PS 21 6254) or heterotrophic (DD-PS 21 6253) or the optical properties and the ion conversions autotrophic (DD -PS 220047) microalgae suspensions were analyzed and the analytical results obtained were compared. By using one or a combination of several of these methods one is able, with less or greater certainty, to associate the active substances with primary or unspecific photosynthetic inhibitors, primary resp. Non-specific respiratory effectors or primary or unspecific effectors of the nitrogen balance. These selection methods are also able to provide information on the onset, course and persistence of the effect expression as a function of the dose and the duration of action of the effectors as well as on the mode of action initiation as by the immediate inhibition via the analysis of dose-dependent effect effect time curves deliver. At the same time the detection of permeation and transport problems of the effectors is made possible by appropriate evaluation methods.

Despite these advances in the screening and characterization of effectors, the discovery of specific potencies of potential effectors is dependent on the subjective choice of test procedure (s) used, as screening involving all known selection procedures is to be rejected for economic reasons. This results in the desire for a screening method, which is also based on suspension cultures of unicellular green algae, but with minimal effort on working time, material and energy maximum information regarding a clear assignment of effectors according to their specifics to a basic drug type allows.

Object of the invention

The aim of the invention is to propose a screening method for tests with autotrophic and heterotrophic suspension cultures of unicellular green algae, which is based on a minimized test and evaluation hierarchy and allows maximum information regarding the assignment of potential effectors according to their activity to basic drug types.

Explanation of the essence of the invention

The object is achieved in that the "screening method for the characterization and selection of effectors" partially different substance-initiated influences the optical properties, the ion conversions and possibly the photosynthetic or respiratory gas exchange rates of autotrophic and heterotrophically cultured microalgae suspensions analyzed in a minimized test hierarchy and the analysis results In a minimized evaluation method, which, however, allows maximum information on the possible assignment of the tested effectors with respect to the shown active specificity to basic drug types, comparative considerations are also provided The proposed evaluation method also provides time-independent, relativized, dose-dependent effect-effect curves, in addition to qualitative statements for the direction of action and the course of action can also be used for quantitative comparisons.

In the "screening method for the characterization and selection of effectors" defined amounts of chemical compounds in parallel or simultaneously with unicellular algal suspensions, which are cultured autotrophically or heterotrophically in a suitable nutrient solution, brought into direct contact and these samples in parallel with untreated comparison cultures at a uniform temperature between 20 ⁰ C and 38 ⁰ C ventilated in the light or in the dark, so that grow and develop on the basis of the performing photosynthesis or the respiratory process.At predetermined times then of samples and comparison cultures or portions of both parallel or in defined Follow the optical properties by means of spectral analytical methods at 688 and 750 nm or other suitable wavelength ranges, the nitrogen ion conversion by means of pH electrodes, nitrate-sensitive electrodes or other nitrogen-sensitive electrodes and if necessary the pH Otosynthetic or respiratory oxygen turnover by means of paramagnet gas analyzers, oxygen-sensitive electrodes or other suitable methods and / or the photosynthetic or respiratory carbon dioxide conversion by means of infrared gas analyzers or other suitable methods in a single operation and subjected to the analysis results obtained comparative considerations.

For the classification of the investigated effectors according to their specific effect in the standardized chlorella tests used in basic types, the following course is proposed in addition to other conceivable test and evaluation hierarchies, which leads to the necessary information with minimal effort and can be further specified by incorporating further findings.

1. Selection of the effectors according to the absolute value pc ₅₀ (A) / 1 Λ which was determined in the autotroph test Depending on the size of the pc ₅₀ (A) values of the effectors in the autotrophic growth test, the active ingredients can be quantified in terms of their demonstrated algicidal activity according to the following rating become.

6th stage

5th step6.1gpC ₆₀ (autotrophic) 4th step 5.2 δ pc ₆ o (autotrophic) 3rd step 4.3 g pC ₅₀ (autotrophic) 2nd step 3.5 ä pC ₅₀ (autotrophic) 1st step PC ₅ 0 (autotrophic)

s 6.1 very effective = § 5.2 strongly effective s 4.3 very effective s 3.5 effective S 2.6not effective S 2.6 not effective

According to this rating, for example, according to the pcsoiAp values in Table 1, the active ingredients atrazine and prometry can be classified as very potent, simazine, metabenzthiazuron (techn.) And bromuron as highly effective, DNOC as well-effective, and amidinothiourea as poorly effective

2. Selection of the effectors by comparison of the quantitative parameters PC ₅₀ /! /, Which were determined in the autotrophic and heterotrophic test variants

According to the size of the Apc _so values resulting from a comparison of the PC ₅₀ data from the autotrophic (A) and heterotrophic (H) test variants according G. (1), the effectors may be in various quantitative levels in terms of their effect on the photosynthesis be classified, with five grading grades are proposed. 1 pc ₅ o = -Ig {ED50}, [ED ₅₀ ] = mol · Γ ¹ ; determined from dose-response relationships negative decimal logarithms of the molar effector concentrations, which cause a 50% inhibition of the autotrophic or heterotrophic growth of synchronous Chlorella vulgaris suspensions.

Apc ₆₀ =

- PC ₅₀ (H)

(D

5th stage Apc ₅₀ s 3.05

4th Stage 3.04 a Apc _5O a 2.18 3rd Stage 2.17 SApC ₅₀ S 1.31 2nd Stage 1.30 a ApC ₅₀ g 0.43 I. Stage Apc _6O g 0.42

true or primary inhibitors of photosynthesis good inhibitors of photosynthesis mediocre inhibitors of photosynthesis small, poor photosynthetic inhibitors unspecific photosynthetic inhibitors

Due to their Apc ₅₀ values according to Table 1, for example, the herbicides simazine and atrazine as true photosynthesis inhibitors, Prometryn, Bromuron and Metabenzthiazuron (techn.) Are classified as good photosynthetic inhibitors and DNOC and amidinothiourea as non-specific photosynthesis inhibitors.

Table 1 pc ₅₀ data ¹¹ for the inhibition of autotrophic (A) and heterotrophic growth (H) of synchronous Chlorella suspensions

PC50 (A) 6.07 substances 6.22 simazine 6.66 atrazine 5.92 prometryne 5.6 Bromuron 5.11 Metabenzthiazuron (techn.) 2.97 DNOC 5.84 amidinothiourea 6.10 A B

PC ₅₀ (H)

Ε (λ = 750ηΐη)

6.14 6.19 6.65 6.30 5.64 5.07 2.97 5.84 5.94

<3.0 ² '

3.13

3.72

3.44

3.40

4.91

<3,6 ² »

4.06

4.18

1) PC ₅₀ = -Ig (ED ₅₀ ) te] = mol · Γ ');

The determinations of the pc ₅₀ values were made by means of absorbance measurements of the suspensions at λ = 680 and λ = 750 nm.

2) At the maximum tested active concentration pe = 3.0 or 3.6 no effect was found.

3. Division of the effectors according to the effects on the substance-initiated influence of the optical properties, for example at 680 and 750 nm in the autotrophic growth test

According to the quality of the active images in the form of plots of the growth parameters in the form of the logarithms of the extinctions, for example at 680 ηm and 750 ηm as an expression of the substance-initiated influences on the chlorophyll development and the general cell growth or in the form of the A'lgE data at 680 and 750nm according to Eq. (2), the effectors can be distinguished into three basic types on the basis of the drug-determined scattering effects.

'9E0, control ""

₍₂₎

~! gtEnde.Control

e, control

A first basic quality shows, by way of example, the effective image Fig. 1, A (A'lgE ₆ 8o / A'lgE ₇₅ o) of simazine. The quality is that compared to the control K dose-dependent with increasing concentration of dose 1 to dose 9, the optical properties at 750 nm are more affected than at 680 nm. By the application of inhibition parameters (A ⁺ IgEeSoM ⁺ IgE ₇₅₀ ), the corresponding Eq. (3) can be determined (Fig. 1, B), this effect is clearly highlighted.

A second basic quality shows as an example the active pattern Fig. 13, A of amidinothiourea. In this case, all measuring points A'lgE ₆ 8 ₀ / A'lgE _{750 form} a more or less good, congruent curve with the control K. The small deviations are probably due to scattering effects, which also occur in Fig. 13, B for the application of optical properties at 680 and 750 nm.

In a third basic quality (effective image Fig. 11, A of DNOC), in contrast to the first basic quality dose-dependent with increasing effector concentration 1 to 8, the optical properties are more affected at 680nm than at 750nm. Also, a comparison in the form of the application of the inhibition parameters for DNOC Fig. 11, B makes it clear that it comes to a drug-determined bleaching of the chloroplasts and thus affecting the photosynthesis by this basic drug type.

4. Classification of the active ingredients by effects when comparing the effects of cell growth, which can be detected, for example, by extinction measurements at 750 nm, with the influence of Nitrationenaufnahme by

corresponding pH changes of the algal suspensions are displayed Such comparisons are in the form of IgE ₆₈ o-pH plots or IgE ₇₅₀ -pH plots or better in the form of A'lge / A'pH- or A ⁺ IgM ⁺ pH plots, wherein the growth parameters Δ'ρΗ according to Eq. (4) and the inhibition parameters Δ ⁺ ρΗ for the impairment of the pH values of the algal suspensions over Eq. (5) allow a detailed classification and differentiation of the active substances. In this case, it is usually sufficient to use the A'lgE ₇₅₀ / A'pH or A ⁺ IgE ₇₅₀ / A ⁺ pH plots (effects C and D) for such considerations.

Δ'ρΗ = ^ΡΗ ° · ^sample ~ ^pHt ' ^sample (4)

PH ₀ , control ~ pH end, control. ,

. + ι, pHt, control ~~ pHt, sample Λ pH = - - (5)

P "o, control" ~ P ^ end. control

Due to their comparable structure, simazine and atrazine show similar complex AIgE ₇₅₀ - Δ'ρΗ or A ⁺ IgE ₇₅₀ - A ⁺ pH curves as an example, Figs. 2, C and D Fig. 4, C and D, which are dose - dependent show by their wave-like shape several successive metabolisms. First, dose-dependent growth affects the growth of the cells more than the ion turnover. Thereafter, the ion turnover is more affected than cell growth, etc.

If one considers the parameters hitherto used for the evaluation of the effect specificity: Ratio pc ₅₀ ( _A ) / pc ₅₀ (H), amount of pc ₅₀ (A), effect pictures Fign. 1 and 2 together, the active substance simazine shows its own quality compared to the other active substances, which could be called a simazine type.

In addition to this basic type of active ingredient, a large number of other basic types of active ingredients are conceivable with regard to their action characteristics, but these must first be characterized by pending investigations.

5. Inclusion of further effects for the qualitative and quantitative differentiation of the active substances according to their activity characteristics

In addition to the selection principles mentioned under 1 to 4, additional qualitative and quantitative effects resulting from either the same tests or additional investigations can be used for further differentiation of the active ingredients. Thus, a differentiated selection of the effectors according to the quality of effect pictures is possible in which, for example, other suitable parameters that are closely related to the growth of the algal suspensions, compared with each other. For example, the effects of the photosynthetic and / or respiratory gas turnover (O ₂ , CO ₂ ) on each other or on the influence of the optical properties at 680 and 750 nm or other wavelengths and with ion conversions or pH values in both test variants can additionally be compared.

If necessary, further studies may be carried out to investigate, and comparatively analyze, the differences in the ion conversions of the ionic turnover of the single-celled algal suspensions determined by the choice of nitrate and ammonium ions. Such special tests further narrow the effect specificity of the effectors, giving more and more concrete guidance as to the potential commercial use.

By comparison of such effect data as pc _{50 (} A), pc ₅ o (H), Apc ₅₀ and impact pictures according to the Fign. 1 to 18 of newly examined substances resulting from the proposed minimized test hierarchy, with a Wirkdaten- and Wirkbildkartei or with the help of electronic data processing of basic drug types that have been proven in practice, one obtains concrete by using the proposed minimized evaluation of the effect data Indications of similar quantities and comparable efficacy and thus of commercial applications of new effectors.

embodiments

Freshly hatched aplanospores of synchronous cultures of unicellular green algae of the species Chlorella vulgaris var. V. Ig a ris, strain BÖHM and BORNS 1972/1, are transferred to an inorganic nutrient solution containing Fe-EDTA complex and trace substances such that each cubic centimeter of the suspension contains about six million Contains algae cells. VLiter of the culture nutrient solution N consists of the three partial nutrient solutions N ₁ , N ₂ and N ₃ ;

1000cm ³ N = ³ N 998Cm Cm ₁ + 1 ³ N ₂ + 1 cm ³ of n. ₃

The nutrient solutions N ₁ , N ₂ and N ₃ contain the following substances:

Nutrient solution N ₁

For the nutrient solution N-, first the stock solutions 1 to 4 by filling the said substance amounts with distilled water. manufactured:

Stock solution 1: 10OgKNO ₃ ZIOOOCm ³

Stock solution 2: 25 g CaCl ₂ .6H ₂ O / 1 000 cm ³

Stock solution 3: 250 g of MgSO ₄ .7H ₂ O / 1 000 cm ³

Stock solution 4: 160g KH ₂ PO _4/1 000cm. ³

These stock solutions must be sterilized (wet sterilization) and stored in a cool place.

From each 5 cm ^{3 of} the stock solution 1, 0.5 cm ^{3 of} the stock solution 2.1 cm ^{3 of} the stock solution 3 and 5 cm ^{3 of} the stock solution 4 by filling with distilled water either 1 000cm ³ or when observing the conditions any amount of nutrient solution N ₁ prepared.

Nutrient solution N ₂

The nutrient solution contains N ₂ in 1 000cm ³ solution 61 mg H ₃ BO _3, 169 mg MnSO ₄ - H ₂ O, 287 mg ZnSO ₄ -7H ₂ O, 2.5 mg CuSO ₄ .5H ₂ O and 12,4mg (NH ₄ I ₂ MoO ₄ .

Nutrient solution N ₃

To prepare the nutrient solution N ₃ , 6.9 g of FeSO ₄ .7H ₂ O and 9.3 g of Na-EDTA are dissolved in distilled water and brought to 1 000 cm ³

with aqua dest. refilled. ,

For the heterotrophic test variant, 0.1% by mass of glucose as organic carbon source and 20 mg / l chloramphenicol are added to the freshly prepared algae suspension.

Per 80 cm ^{3 of} the suspension thus prepared are introduced into a culture tube and inoculated with 1 cm ³ different concentrated aqueous solution of the substances to be tested according to Table 1 and the effectors A and B to be tested or as untreated controls in the autotrophic test variant at 37 ° C and gassed with purified air to which 2VoI .-% carbon dioxide is added, fumigated or gassed in the heterotrophic test variant only at 37 ° C in the dark with purified air, so that all conditions required for photosynthesis or for heterotrophic growth are.

While cells suspended in broth normally grow and develop in the untreated control cultures, growth and ion turnover in the chemically-spiked samples are more or less affected when different concentrations of substance more or less disturb photosynthesis, respiration, or nitrogen balance. In a defined time sequence of the comparison cultures and the samples treated with the substances, the optical properties at 680 and 750 nm are measured as growth parameters and the pH as a measure of the nitrogen balance.

The results of the analyzes are shown in Table 1 and Figures 1 to 18.

Table 1 contains the effective quantities PC ₅₀ (A), pcsoim and ApC ₅₀ , which are usually accessible from dose-effect studies in a pre-screening in which the effective range of the effectors is limited and in the manner indicated (see Table 1). are defined. Of all drugs, the growth parameters AMgE ₆₈₀ , AIgE ₇₅₀ and Δ'ρΗ determined by equations (2) and (3) and the inhibitory parameters A ⁺ IgE ₆ S ₀ , A ⁺ IgE obtainable via equations (4) and (5) ₇₅₀ and A ⁺ pH in the form of impact pictures compared. In the panels A and C of Figures 1 to 18 were once the growth parameters A ¹ IgE ₆₈₀ as a measure of Chlorophyllbeeinträchtigung and A ¹ IgE ₇₅₀ as a measure of the general cell growth and the A'lgE ₇₅₀ data with the A'pH values as a measure of the nitration uptake influences compared. The images B and D of FIGS. Figures 1-18 contain comparisons of the respective inhibition parameters in the form of A ⁺ IgE ₆₈₀ ZA ⁺ IgE ₇₅₀ - and A ⁺ IgE ₇₅₀ ZA ⁺ pH plots.

Thus, the effect of Fig. 1, A for simazine shows that compared to control K with an increasing dose of 1 to 9, general cell growth (A ¹ IgE ₇₅₀ ) is slightly more affected than chlorophyll growth (A'lgE ₆₈₀ ), whereas this is relative low effect at the beginning of the curves is most evident. The application of the inhibition parameters A ⁺ IgE ₆₈₀ ZA ⁺ IgE ₇₅₀ in Fig. 1, B confirms the statements of Fig. 1, A. It can be clearly seen that all doses 1 to 9 a stronger inhibition of cell growth, indicated by the corresponding A ⁺ lgE ₇₅₀ data, determine.

1, A and B can be inferred that simazine, in addition to influencing photosynthesis or choroplasts, primarily leads to a surface modification or change in the shape of the cells, which results from the extinction measurements at 750 nm and in this case indicate an apparent greater tangent of cell growth.

A very different picture shows the effect pictures in which the growth parameters A ¹ IgE ₇₅₀ with the corresponding A'pH values, Fig.2, C and the inhibition parameters A ⁺ IgE ₇₅₀ with the A ⁺ pH data, Fig. 2, D to be compared.

Thus, Fig. 2, C for simulating cell growth and nitrate content by simazine shows several metabolisms indicated by the multi-wave A'lgE ₇₅₀ -A'pH curves. Dose-dependent, cell growth is increasingly affected in a primary step more than influencing the nitrate level. The dose 7 leads to a blockage of nitrate uptake with simultaneous further growth of the cells. The very strong doses 8 and 9 lead to a proton emission, because a pH decrease is indicated. In a secondary process, the influence on the nitrate level is then more strongly affected compared to cell growth. A comparison of the corresponding A ¹ IgE ₇₅₀ -A'pH curves also shows that with decreasing doses as the curves continue, the corresponding ratio A'lgE ₇₅₀ ZA'pH of control K is approximated. This suggests repair effects. A very different contribution to the specifics

Here, it is clearly evident that, in a primary metabolism, first the dose-dependent growth of the cells is more strongly inhibited than the ion turnover. In a secondary process, the exchange of nitrate ions for hydroxide ions is then significantly more inhibited than cell growth in a dose-dependent manner. Due to the similar structure of atrazine and simazine, comparable efficacy parameters pc ₅₀ and ApC ₅₀ as well as comparable effects on the optical properties and pH of the algal suspensions are to be expected. This is confirmed by the pc ₅₀ and Apc ₅₀ data in Table 1 and the knuckles A, B, C and D in Figs. Slight differences are shown only in the comparison of the active sites C and D in FIGS. 2 and 4 for simazine and atrazine, which are likely to be structurally related and manifest themselves in atrazine in a comparatively weakened influencing of the same metabolisms compared to simazine. The active data in Table 1 and the active images A, B, C and D of Prometryn and Metabenzthiazuron, Fign.5 and 6 and Fign.7 and 8, are in principle to compare with existing quantitative differences with those of simazine or atrazine. Thus, these four active ingredients can be assigned to a basic drug type for whose pattern recognition the mentioned active data and active images can be used.

The effects and effects of Bromuron, Fign. 9 and 10 are in principle qualitatively comparable to those of simazine and illustrate similar mechanisms of action and metabolism, but here they are displayed in a much attenuated form. In contrast to the active ingredients considered so far, the effective quantities pc ₅₀ and ApC ₅₀ in Table 1 and the action patterns A, B, C and D of DNOC in FIGS. 11 and 12 to another basic type of herbicidal active ingredients. In addition to quantitative differences in the pc ₅₀ value of DNOC to simazine, atrazine, prometry, bromuron and metabenzthiazuron (techn.), The new quality of the Apc ₅₀ value of 0.20 stands out, which already indicates that DNOC, in contrast to The previously considered drugs is only a non-specific photosynthesis inhibitor. A comparison of the growth parameters AIgE ₆₈₀ ZAIgE ₇₅₀ in Fig. 11, A for DNOC has, in contrast to the previously considered agents from another effect, which can be used for pattern recognition. The A'lgE ₆ 8o / A'lgE _75O curves for doses 5 to 8 indicate that the optical properties at 680nm and thus photosynthesis are more inhibited than cell growth. When considering the application of the inhibition parameters (A ⁺ IgE ₆₈₀ / A ⁺ IgE ₇₅₀ ) in FIG. 11B, only few effects for elucidating the effect specificity can be recognized. When looking at the plots of the growth parameters A'lgE ₇₅₀ / A'pH in Fig. 12, C and the inhibiting parameter in Fig. 12, D, respectively, the curves for cans 5 to 8 show that the cell growth is more inhibited than that Ion turnover, this effect has no clear dose dependence. The wave-like course of the curves indicates that in a secondary process the nitrate balance and in a tertiary process, the cell growth are more affected. The curve 5 reaches the curve of the control K, which in turn indicates repair processes.

Overall, it can be deduced from FIGS. 11 and 12 for the specificity of action of DNOC that this effector is essentially non-specific, assuming a primary chlorophyll impairment.

Due to the effect parameters in Table 1 and the action pictures A, B, C and D in FIGS. 13 and 14, amidinothiourea may be classified as another basic type of effectors, characterized by a relatively low effect in the standardized algae test and a relatively unspecific effect in the comparisons of the growth and inhibition parameters in FIG. Only the effect pictures Fig. 14, C and D indicate a dose-dependent stronger influence on the nitration household compared to the general cell growth.

The active compounds A and B, for the comparable activity data pc ₅₀ and APC ₅₀ (Table 1) were determined, but have in the plots of the growth and Hemmparameter in the active images A, B, C and D in Figs. 15 to 18 qualitative partially opposing effects, so that both active ingredients are due to their specifics of two additional basic drug types.

Already the effect parameters (Table 1) and the effectors Fign. 1 to 18 of the nine investigated active substances make it clear that the proposed minimized test hierarchy based on autotrophically and heterotrophically cultured algal suspensions and the proposed minimized evaluation system of the measurement data can lead to clear information about the active substance specificity as a screening method for the characterization and selection of effectors let use.

Claims (7)

1. A screening method for the characterization and selection of effectors, characterized in that by means of a minimized test hierarchy, the partially substance-initiated influences of the optical properties, the ion conversions and optionally the photosynthetic and / or respiratory gas turnover in two standardized test variants based on autotrophically and heterotrophically cultured algal suspensions, analyzed and the analysis results are subjected to a minimized evaluation mode in order then to compare the absolute effective quantities, the effective quantitative differences from both test variants and those in which the influences on the optical properties, for example two wavelengths, the ion conversions or the pH Values and, if appropriate, the gas exchange conversions are regarded as effect effect-effect effect curves as a function of the dose, typical statements on the effect specificity of the examined effe To obtain these, which are then compared with corresponding data well-studied, for example, commercially distributed drugs using a Wirkdaten- and Wirkbildkartei, electronic data processing or other comparative methods to assign the investigated drugs according to their specific effect shown in the standardized tests specific drug types and statements to derive mechanisms of action, metabolisms and possible applications. 2. The method according to item 1, characterized in that as autotrophic and heterotrophic cell suspensions all susceptible autotrophic and heterotrophic unicellular green algae can be used. 3. The method according to item 1 and 2, characterized in that the optical properties of the microalgae suspensions by means of spectral colorimetry, spectrophotometry or nephelometry at one or two to η different wavelength ranges or entire spectral ranges in the infrared, visible or ultraviolet spectral range are analyzed. 4. The method according to item 1 and 2, characterized in that the ion conversion of the microalgae suspensions by means of pH electrodes, nitrate-sensitive electrodes or other ion-sensitive electrodes, polarographic methods or other electrochemical methods, kond.uktometrischer methods, spectral analysis method or by combining several of these methods analyzed becomes. 5. The method according to item 1 and 2, characterized in that the oxygen conversion by paramagnet gas analyzers, oxygen-sensitive electrodes, polarography and other electrochemical electrodes, manometric method, the Winkler method or by combining several of these methods is analyzed. 6. The method according to item 1 and 2, characterized in that the carbon dioxide conversion is analyzed by means of infrared gas analyzers, ¹⁴ C method, photometric methods or by combining several of these methods. 7. The method according to item 1 to 6, characterized in that the optical properties, the ion conversion and the gas exchange of the autotrophic or heterotrophic microalgae suspensions are analyzed in a single operation continuously or in a defined time sequence in parallel or simultaneously. For this 18 pages drawings