caa a22 4500 465748821 CHVBK 20180323111828.0 cr unu---uuuuu 170327e19900101xx s 000 0 eng 10.1007/BF00322524 doi (NATIONALLICENCE)springer-10.1007/BF00322524 Microbiological detection and quantitation of bioactive compounds in vegetation matrix by laser light scattering [Elektronische Daten] [I. Felkner, Brenda Worthy] Summary: New approaches have been developed for the assessment of low levels of bioactive substances such as pesticides, organic and inorganic toxicants, as well as growth stimulating substances present in vegetation matrices. The new technology uses a laser /bacterial biossay which is capable off differentiating between various bioactive substances based on their mechanism of action, i.e., toxicity or nutritional fortification at the molecular/cellular level. The system uses a battery of isogeneic Bacillus subtilis mutant strains that were genetically constructed to respond differentially to specific toxicants. The response in terms of growth inhibition/stimulation is monitored by differential light scattering of a laser which is integrated with a computerized system that collects and analyzes the data. Making 1200 measurements on each sample set within 2 to 4 seconds, complete bioresponse data including concentration-related response is obtained on most samples within 60 min. By utilizing a non-toxic cocktail that was developed to solubilize and disperse water insoluble materials into an aqueous matrix, a number of pesticides including carbaryl, malation, chlorsulfuron, glyphosate, tributyltin, and beta-exotoxin could be assayed, specifically characterized, and their concentration directly correlated with the bioresponse of the bacterial strains. Since there was a differential response between mutant bacteria to each compound, a profile unique to each pesticide could be developed and stored in a software recognition library. Finally, the various pesticides could be detected in a vegetation matrix, e.g., citrus leaf, without using a chemical/physical extraction procedure. In addition, the effect of the leaf matrix on the bacterial response could be assessed. Thus, the laser-bacterial assay promises to be a rapid and inexpensive analytical tool for chemical assay in a complex matrix. Springer-Verlag, 1990 Felkner I. Technical Assessment System, Inc., 20007, Washington, DC, USA aut Worthy Brenda Technical Assessment System, Inc., 20007, Washington, DC, USA aut Fresenius' Journal of Analytical Chemistry Springer-Verlag 338/4(1990-01-01), 489-494 0937-0633 338:4<489 1990 338 216 https://doi.org/10.1007/BF00322524 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00322524 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Felkner I. Technical Assessment System, Inc., 20007, Washington, DC, USA aut NATIONALLICENCE 700 1- Worthy Brenda Technical Assessment System, Inc., 20007, Washington, DC, USA aut NATIONALLICENCE 773 0- Fresenius' Journal of Analytical Chemistry Springer-Verlag 338/4(1990-01-01), 489-494 0937-0633 338:4<489 1990 338 216 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer