Franz Hadacek

• Doctor of Philosophy
• staff member at University of Göttingen

This chapter presents a holistic and quantitative approach to the carbon cycle in plant systems biology. It includes (rapid) phenotyping and monitoring of physiological key interactions of plants with its respective soil and atmospheric environment (soil plant atmospheric continuum—SPAC). The approach aims at qualifying and quantifying key componen...

The large structural diversity of specialized metabolites represents a substantial challenge in untargeted metabolomics. Modern LC–QTOF instruments can provide three- to four-digit numbers of auto-MS/MS spectra from sample sets. This case study utilizes twelve structurally closely related flavonol glycosides, characteristic specialized metabolites...

Simple Summary Genome duplication or multiplication, polyploidy, has contributed substantially to the evolutionary success of plants. Polyploidy is often connected to a higher resilience to environmental stress. We have chosen the goldilocks, the Ranunculus auricomus complex, to study effects of light stress. In this species complex, diploid (2x),...

Flavonoids are rather common plant phenolic constituents that are known for potent antioxidant effects and can be beneficial for human health. Flavonoids with a pyrogallol moiety are highly efficient reducing agents with possible pro- and antioxidant effects, depending on the reaction milieu. Therefore, the redox properties of myricetin and triceti...

The evolutionary advantage of different sexual systems in multicellular eukaryotes is still not well understood, because the differentiation into male and female individuals halves offspring production compared with asexuality. Here we propose that various physiological adaptations to oxidative stress could have forged sessility versus motility, an...

Reactive oxygen species (ROS) are known for their participation in various physiological and pathological processes in organisms, including ageing or degeneration. Kynurenine pathway metabolites, such as kynurenic (KYNA) or xanthurenic (XA) acid, can affect neurodegenerative diseases due to their ROS scavenging and Fe ion coordination complex forma...

The volume and complexity of commercial bioreactors for sterile hydroponics and hairy roots are too large for comparative analysis of many cultures. Here a small-scale bioreactor fabricated from standard glass materials and suitable for both airlift and bubble aeration mode is described. The performance of the bioreactor was tested by growing oilse...

Background: The alkaloid 8-hydroxyquinoline (8HQ) is well-known for various biological activities, including antioxidant effects and especially for the formation of coordination complexes with various transition metals, such as iron, amongst others. Therefore, 8HQ was extensively explored as a promising antineurodegenerative agent. However, other a...

The African pepper bark tree, Warburgia ugandensis, accumulates antimicrobial drimane sesquiterpenes in all of its organs. One hypothesis states that plant defense compounds determine endophyte community structure. Another hypothesis suggests that they just facilitate the endophytic lifestyle by exerting a balanced antagonism. To explore this, a re...

This book is for biologists and other system analysts struggling with big-data statistics. The approach of the authors, having instructed students and consulted colleagues for two decades, is not to explain statistics anew. Rather, we aim to put forward a praxis oriented method to stepwise apply statistics according to research questions asked, to...

The flavanol (±)-catechin shows an OH group but no 4-keto group on ring C (C3), and no conjugation between ring A and B. The related flavanone (+)-eriodictyol has a keto group on C4 but no 3-OH group on ring C. (+)-Taxifolin, another flavanone, has an OH on C3 and a keto group on C4 of the C ring. Deoxyribose degradation assay systems, with hydroge...

Disposal of organic plant wastes and by-products from the food or pharmaceutical industries usually involves high costs. In the present study, 42 samples derived from such by-products were screened in vitro against Cryptosporidium parvum, a protozoan parasite that may contaminate drinking water and cause diarrhoea. The novel bioassay was previously...

Little attention has been paid to the evolutionary consequences of the colonizing dynamics and succession processes following glacier retreat. Here we studied hybrid populations that have recently formed and established on glacier forefields of the European Alps owing to secondary contact of a lowland colonizer with a subalpine species. We analyzed...

Meiosis, the key step of sexual reproduction, persists in facultative apomictic plants functional to some extent. However, it still remains unclear how and why proportions of reproductive pathways vary under different environmental stress conditions. We hypothesized that oxidative stress mediates alterations of developmental pathways. In apomictic...

Low-molecular-weight metabolites (LMWMs) comprise primary or central and a plethora of intermediary or secondary metabolites, all of which are characterized by a molecular weight below 900 Dalton. The latter are especially prominent in sessile higher organisms, such as plants, corals, sponges and fungi, but are produced by all types of microbial or...

The tryptophan metabolite, quinolinic (2,3-pyridinedicarboxylic) acid, is known as an endogenous neurotoxin. Quinolinic acid can form coordination complexes with iron or copper. The effects of quinolinic acid on reactive oxygen species production in the presence of iron or copper were explored by a combination of chemical assays, classical site-spe...

Anthranilic acid (ANA) and 3-hydroxyanthranilic acid (3-HANA) are kynurenine pathway intermediates of the tryptophan metabolism. A hitherto unemployed method combination, differential pulse voltammetry, mass spectrometry (nano-ESI–MS), deoxyribose degradation and iron(II) autoxidation assays has been employed for studying of their redox chemistry a...

Iron is an essential co-factor for many enzymes that catalyze electron transfer reactions. It is well known that so-called "poorly liganded" iron can increase ROS concentrations and trigger oxidative stress that is capable of initiating apoptosis. Conversely, controlled ROS production has been recognized as an integral part of cellular signaling. E...

The antioxidant activity of ethanol extracts of Atrichum undulatum, Polytrichum formosum (Polytrichaceae), Pleurozium schreberi (Entodontaceae) and Thuidium tamariscinum (Thuidiaceae) was evaluated by an electrochemical method (cyclic voltammetry) and standard photometric methods: Fe(III) to Fe(II) reducing power, nitric oxide scavenging (NO) assay...

Metabolite profiles (GC–−MS), drimane sesquiterpenes, sugars and sugar alcohols, were compared with bacterial and fungal endophyte communities (T-RFLP, DNA clones, qPCR) in leaves and roots of the pepper bark tree, Warburgia ugandensis (Canellaceae). Ten individuals each were assessed from two locations east and west of the Great Rift Valley, Kenya...

Arbuscular mycorrhizal fungi (AMF) can control soilborne diseases such as Fusarium oxysporum f.sp. lycopersici (Fol). Root exudates play an important role in plant–microbe interactions in the rhizosphere, especially, in the initial phase of these interactions. In this work, we focus on (i) elucidating dynamics in root exudation of Solanum lycopersi...

Quinolinic acid (2,3-pyridinedicarboxylic acid, QUIN) is a well-known neurotoxin. Consequently, QUIN could produce reactive oxygen species (ROS). ROS are generated in reactions catalyzed by transition metals, especially iron (Fe). QUIN can form coordination complexes with iron. A combination of differential pulse voltammetry, deoxyribose degradatio...

The maintenance of sexual reproduction in eukaryotes is still a major enigma in evolutionary biology. Meiosis represents the only common feature of sex in all eukaryotic kingdoms, and thus, we regard it a key issue for discussing its function. Almost all asexuality modes maintain meiosis either in a modified form or as an alternative pathway, and f...

Using iron-deprived (-Fe) chlorotic as well as green iron-deficient (5 μM Fe) and iron-sufficient supplied (50 μM Fe) leaves of young hydroponically reared Brassica napus plants, we explored iron deficiency effects on triggering programmed cell death (PCD) phenomena. Iron deficiency increased superoxide anion but decreased hydroxyl radical (•OH) fo...

Invasion of non-native species is among the top threats for the biodiversity and functioning of native and agricultural ecosystems worldwide. We investigated whether the herbivory of the slug Arion vulgaris (formerly Arion lusitanicus; Gastropoda), that is listed among the 100 worst alien species in Europe, is affected by soil organisms commonly pr...

Metabolomics has emerged as a key technique of modern life sciences in recent years. Two major techniques for metabolomics in the last 10 years are gas chromatography coupled to mass spectrometry (GC–MS) and liquid chromatography coupled to mass spectrometry (LC–MS). Each platform has a specific performance detecting subsets of metabolites. GC–MS i...

Some antioxidants have been shown to possess additional pro-oxidant effects. Diverse methodologies exist for studying redox properties of synthetic and natural chemicals. The latter are substantial components of our diet. Exploration of their contribution to life-extending or -compromising effects is mandatory. Among reactive oxygen species (ROS),...

Pharmacological studies focus on susceptibility of pathogenic microbes against specific drugs or combinations of them, ecological studies on substrate utilization efficiency of variable microbial communities. The MicroResp™ system was especially developed to study soil microbial communities. It was slightly modified to facilitate exploring of micro...

Cryptosporidiosis caused by Cryptosporidium spp. is an important diarrhoeal disease observed in farm animals and humans, especially in young or immunocompromised individuals. A novel cell culture assay for testing extracts and pure compounds against Cryptosporidium parvum in 96-well microplate format was established and evaluated. It is based on pr...

Flavonoids are ubiquitous phenolic plant metabolites. Many of them are well known for their pro- and antioxidant properties. Myricetin has been reported to be either a potent antioxidant or a pro-oxidant depending on the conditions. The reaction conditions for the pro- and antioxidant activities were therefore investigated using variations of the d...

Plant and microbial community composition in connection with soil chemistry determines soil nutrient cycling. The study aimed at demonstrating links between plant and microbial communities and soil chemistry occurring among and within four sites: two pine forests with contrasting soil pH and two grasslands of dissimilar soil chemistry and vegetatio...

8-Quinolinol (oxine, 8-hydroxyquinoline) is a simple aromatic alkaloid with allelopathic, antibacterial, antifungal, and cytotoxic activities. Generally, it is assumed that 8-quinolinol toxicity depends on transition metal chelation that negatively affects their availability for metalloenzymes in the cell or reactive oxygen species generation (ROS)...

Sphagnum mosses represent a main vegetation component in ombrotrophic wetlands. They harbor a specific and diverse microbial community with essential functions for the host. To understand the extend of host specificity and impact of environment, Sphagnum fallax and Sphagnum angustifolium, two phylogenetically closely related species, which show dis...

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

In plants, accumulation in specific compartments and huge structural diversity of secondary metabolites is one trait that is not understood yet. By exploring the diverse abiotic and biotic interactions of plants above- and belowground, we provide examples that are characterized by nonlinear effects of the secondary metabolites. We propose that redo...

Traditional breeding of ornamentals has led to a scent reduction of many floricultural varieties due to a negative correlation between flower longevity and fragrance. Vigna caracalla L. Verdc. (Leguminosae: Papilionoideae) produces large flowers with an intense, pleasant fragrance. The objective of this study was to identify, using headspace analys...

Iron is a transition metal that forms chelates and complexes with various organic compounds, also with phenolic plant secondary metabolites. The ligands of iron affect the redox potential of iron. Electrons may be transferred either to hydroxyl radicals, hydrogen peroxide or molecular oxygen. In the first case, oxidative stress is decreased, in the...

(+/-)-Catechin is a flavan-3-ol that occurs in the organs of many plant species, especially fruits. Health-beneficial effects have been studied extensively, and notable toxic effects have not been found. In contrast, (+/-)-catechin has been implicated as a 'chemical weapon' that is exuded by the roots of Centaurea stoebe, an invasive knapweed of no...

Juglone, 5-hydroxy-1,4-naphthoquinone, is known for its wide range of biological activities. It has been suggested that juglone's excellent redox cycling properties contribute to this reputation. Many biological activities are nonlinear with low concentrations exerting stimulating effects, whereas only higher concentrations cause inhibition. Here,...

The major aim of this paper was to explore the mechanistic basis of induced defensive ant response in myrmecophytic Piper species and their ant‐partner Pheidole bicornis by combining experimental trials and chemical analysis. In field experiments, the response of Pheidole ants to simulated stem‐damage of their host plant was documented. Their react...

Ant-dispersed plants usually produce seeds with appendages (elaiosomes) as reward for ants. Plants that produce high-quality elaiosomes benefit because ants preferentially disperse their diaspores. We therefore hypothesized that seeds and elaiosomes differ in chemical composition in ways that make elaiosomes of high nutritional quality for ants, ca...

Gradient odour emissions in the inflorescence of the Araceae Sauromatum guttatum aim to attract a wide range of insects into the floral chamber. The volatiles are emitted from the spadix appendix, as well as the club-shaped organs located directly above the female flowers. Volatile analysis of various regions of the appendix and the club-shaped org...

In general, we assign the term secondary metabolites to low molecular weight compounds produced by living organisms that apparently lack life-sustaining functions. Instead, they are assumed to contribute to the producing organism’s survival in the ecosystem. By contrast, primary metabolites are practically indispensable (Hartmann 1996). The congrue...

High acidity, low temperature and extremely low concentration of nutrients form Sphagnum bogs into extreme habitats for organisms. Little is known about the bacteria associated with living Sphagnum plantlets, especially about their function for the host. Therefore, we analysed the endo- and ectophytic bacterial populations associated with two widel...

The absolute configuration of secondary hydroxy functions of seven natural occurring polyyne derivatives has been elucidated by the application of Mosher method of diastereomeric methoxy-2-trifluoromethyl-phenylacetyl (MTPA) ester formation. High-performance liquid chromatography with diode array detection (HPLC-DAD) of the reaction mixture using a...

Various ecological models explain species diversity, and it has been found that microbial biodiversity is closely linked to plant biodiversity. A mathematical exploration of a feedback model among plants, their competitor plants, and the microbial communities of both concludes that negative feedbacks promote the coexistence of species. In this cont...

The flower of Nelumbo nucifera displays some highly specialized structural details apparently related to its pollination ecology. The functional significance of these structures, however, is still under debate. This paper presents new anatomical and chemical data that contribute to our knowledge of the floral life of the lotus. Special focus is dir...

From the roots of various Stemona species four new dehydrotocopherols (chromenols) were isolated and their structures and stereochemistry elucidated by spectroscopic methods. The double bond between C-3 and C-4 proved to be a typical chemical character of the genus found in most of the species. Various C-methylations of the aromatic ring reflect di...

Supercritical fluid extracts (carbon dioxide without modifiers) of St. John's Wort (Hypericum perforatum L., Clusiaceae) were analyzed by GC-MS, HPLC-DAD and HPLC-DAD-MS. Besides the dominating phloroglucinols hyperforin (36.5 +/- 1.1%) and adhyperforin (4.6 +/- 0.1%), the extracts mainly contained alkanes (predominantly nonacosane), fatty acids an...

Seven new naturally occurring 3-butylisocoumarins were isolated and identified from lipophilic extracts of aerial as well as underground organs: corfin (17) and 3'-hydroxycorfin (18) from the roots of Chamaemelum mixtum and (-)-(R)-2'-methoxydihydroartemidin (5), (+)-(S,R)-epoxyartemidin (6a), dracumerin (12), (+)-(R)-(E)-3'-hydroxyartemidin (13),...

A series of 3-hydroxy- and 3-bromobutyl-substituted isocoumarins was synthesized. The absolute configurations of three isocoumarin derivatives from Artemisia dracunculus, namely (–)-epoxyartemidin, (–)-2-methoxydihydroartemidin, and (+)-3-hydroxyartemidin were determined by chemical means via derivatization, kinetic racemate resolution (Horeau meth...

Abstract Peucedanum alsaticum and Peucedanum cervaria represent characteristic umbellifers (Apiaceae) of calcareous grasslands in Central and Eastern Europe. Both accumulate glucose, fructose, mannitol and sucrose as dominant carbohydrates in their roots. The objective of the study was to determine if endophytes utilise host plant carbohydrates dif...

Peucedanum alsaticum and Peucedanum cervaria represent characteristic umbellifers (Apiaceae) of calcareous grasslands in Central and Eastern Europe. Both accumulate glucose, fructose, mannitol and sucrose as dominant carbohydrates in their roots. The objective of the study was to determine if endophytes utilise host plant carbohydrates differently...

Referee: Dr. Peter B. Kaufman, Dept. of Biology, University of Michigan, Ann Arbor, MI 48109-1048 Traditionally, secondary metabolites in plants have been investigated by phytochemists. Originally classified as waste products, these compounds more recently have been investigated extensively by ecologists and pharmacologists, and many complex biolog...

Eight flavaglines, six cyclopenta[b]benzofurans, a cyclopenta[bc]benzopyran, and a benzo[b]oxepine, together with an aromatic butyrolactone were isolated from Aglaia odorata, A. elaeagnoidea, and A. edulis (Meliaceae) and tested against the three plant pathogens Pyricularia grisea, Fusarium avenaceum, and Alternaria citri for antifungal properties....

Antifungal testing of filamentous fungi generally suffers from incomparability of results. In order to illustrate this problem, the polyacetylene falcarindiol and the naphthoquinone juglone, two known antifungal natural products, were assayed in various dilution and diffusion bioassays against three selected microfungi, Botrytis cinerea, Cladospori...

Isolation of polyacetylenes from aerial and subterranean parts of water hemlock, Cicuta virosa L. (Apiaceae. Apioideae), yielded eleven C (17)-polyacetylenes: cicutoxin, cicutol, (8 E,10 E)-heptadecadiene-4,6-diyne-1,12-diol (cicudiol, 7), 2,3-dihydrooenanthetol and (8 E)-heptadecene-4,6-diyne-1,10-diol already known to occur in water hemlock, the...

Underivatized alkylbutenolides from several Peucedanum species including P. alsaticum L., P. austriacum (Jacq.) Koch, P. arenarium Waldst. & Kit., P. venetum (Sprengel) Koch and P. rablense (Wulfen) Koch (Apiaceae-Apioideae) were separated by high performance liquid chromatography and preparative chromatography on a reversed phase system at a pH of...

From the lipophilic leaf extracts ofGlycosmis mauritiana andG. parviflora (Rutaceae-Aurantioideae), the novel thiocarbonic acid derived imide ritigalin was isolated as major component by MPLC and TLC. The structure was elucidated by spectroscopic evidence (1H,13C NMR; MS; IR; UV).

Seven new sulphones derived from methylthiopropenoic acid amides have been isolated as dominant components from the methanolic leaf extract of Glycosmis angustifolia collected in Sri Lanka. All derivatives contained substituted phenethylamine moieties with prenyloxy (dambullins) or geranyloxy groups (gerambullins) in the para-position. Additional o...

Peucedanum arenarium Waldst. & Kit.,P. austriacum (Jacq.) Koch,P. coriaceum Reichenb.,P. longifolium Waldst. & Kit,P. officinale L.,P. oreoselinum (L.) Moench,P. ostruthium L., andP. palustre (L.) Moench accumulate different structural types of coumarins including simple coumarins, linear furanocoumarins, linear dihydropyranocoumarins, angular dihy...

Leaf extracts from different Sri Lankan provenances of Glycosmis mauritiana and G. pentaphylla have been compared by HPLC analyses and tested for antifungal activity. All collections of G. pentaphylla are uniformly characterized by the known alkaloids arborine, skimmianine and arborinine, whereas the different provenances of G. mauritiana differ by...

Four new sulphur containing amides have been isolated from the methanolic leaf extract of the Malayan Glyeosmis chlorosperma. Their structures and stereochemistries were elucidated on the basis of spectroscopic evidence and were shown to represent two pairs of isomers: the dominating (E)-isomer penangin together with traces of the (Z)-isomer isopen...

The lipophilic root extract of Peucedanum alsaticum afforded four highly unstable butenolides which could be separated by HPLC. Whereas the stereochemistry of three olefinic derivatives, previously isolated only as their methyl ethers, were now established by 1H NMR, the structure of a new acetylenic lactone was additionally confirmed by 13C NMR. T...

Over the past years, the knowledge on signaling in plant–microbe interactions has increased to a great extent. However, the signal communication of roots is still not satisfactorily understood. Our work was initiated to elucidate the plant response in a biological system consisting of the crop plant tomato, the arbuscular mycorrhizal fungus Glomus...