The current greening of chemical production processes going along with a rising interest for the utilization of biogenic feedstocks recently revived the research to find new ways for the degradation of the complex lignin-backbone by means of biocatalysis and combined chemo-enzymatic catalysis. Lignin, which accumulates in 50 million t/a, is regarded as a potential substitute for phenolic and other aromatic, oil-based chemicals in the upcoming post oil age. The cleavage of the β-O-4-aryl ether linkage is the most favoured, since it accounts for approximately 50% of all ether linkages in lignin. This enzymatic cleavage was proposed to be a part of the lignin catabolism in the proteobacterium Sphingobium sp. SYK6.Three enzymes, LigD, a Cα-dehydrogenase, LigF, a β-etherase and LigG, a glutathione lyase, are supposed to be involved in lignin degradation. We cloned and recombinantly expressed these genes in E. coli and determined their pH and temperature optima on the lignin model substrate 1-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol 1. Using an NAD + dependent glutathione reductase from Allochromatium vinosum (AVR) we established an efficient way to regenerate the co-substrates NAD + and glutathione allowing for a self-sufficient balanced enzymatic cascade with net internal hydrogen transfer (hydrogen borrowing). We showed the capability of this enzyme system to release lignin monomers from complex lignin structures coming from differently prepared real lignin substrates. This novel enzyme system could become a useful tool to release lignin monomers from complex lignin structures. † Electronic supplementary information (ESI) available. See

Tracking the dispersal of seeds by fruit‐eating animals in tropical rain forests is crucial to further our understanding of plant–frugivore interactions and their impacts upon forest regeneration and plant population dynamics. We tested the feasibility of tracking bat‐dispersed seeds in a Philippine lowland rain forest with the help of fluorescent pigment. The powder was mixed with acetone and sprayed to ripe fruits of fig trees, i.e., Ficus septica and F. variegata. During nightly monitoring using a hand‐held ultraviolet lamp bat deposits (seed‐containing spat outs and feces) could successfully be detected. Distances and directions of deposit sites to the focal trees were recorded and seed shadow areas were analyzed. Bats dispersed most of the seeds less than 50 m away from the parent plants resulting in seed shadow areas < 0.30 ha in size. An in situ fruit preference experiment showed that fluorescent powder is unlikely to deter bats from feeding on ripe figs. In conclusion, the technique is simple, inexpensive, noninvasive, applicable to different fields of research and allows one to follow the fate of seeds from known sources.

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