Potential allelochemicals guided isolation

Experiment The isolation and identification of bioactive molecules is a major goal of chemical ecology and can be achieved by guided bioassays on suitable sensitive systems. Here a bioassay based on the growth and morphogenesis of protonemal system of bryophytes grown in vitro is described to test potential allelochemicals from lichen Cladonia foliacea. 

Table 1 Experiment 2. Guided isolation and identification of potential allelochemicals from Cladonia foliacea. O, fraction O P, fraction P UA, usnic acid ca, caulonema ch, chloronema sb, side branches. Protonemal system from shoots after 21 days in culture tested against three fractions from C. foliacea thallus and in control Mohr medium. The observations represent means calculated from about 300 protonemata for each species. P. squarrosa is the species least affected, while 7. flavovirens is the most affected by lichen fractions. 

Spore germination and protonemal growth and morphogenesis are therefore, useful systems to test in vitro, with good reproducibility, potential allelochemicals both through direct co-existence test in vitro or using the described bioassays to monitor/guide isolation, purification, characterization of chemical structure of bioactive compounds. 

Fig. 4 Experiment 2 Guided isolation and identification of potential allelochemicals from Cladonia foliacea. A, Regenerating protonema from Pleurochaete squarrosa leaves after 14 days in control sample B, regenerating protonema from P. squarrosa after 14 days in the inhibiting fraction P from lichen Cladonia foliacea . C, regenerating protonema from P. squarrosa after 14 days in the stimulating fraction O from lichen Cladonia foliacea. Light microscope (a and c x 25, b x 50).

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