Chemie in Unserer Zeit最新文献

An important strategy for delivering pharmacologically active compounds to the desired site of action in the organism is the prodrug concept. Such drugs contain, for example, a precursor of the actual active ingredient or a compound masked by an added partial structure. In the organism, the prodrug is metabolized into a drug. This principle is explained using several examples. In addition, a suggestion is made as to how this topic can be implemented in chemistry lessons at upper secondary level.

The fight against global warming can only succeed by replacing fossil fuels with renewable energies. However, most renewable energy sources are intermittent and require storage concepts in order to have energy available at all times and in a predictable manner. In this context, chemical energy carriers, especially hydrogen, are important. Green hydrogen as an energy vector can be obtained simply by electrolysis of water and can be used universally. Hydrogen can be stored in other chemical compounds for storage and transportation. This reversibly converts the volatile gas hydrogen into a safer liquid or solid. In liquid or solid form, hydrogen can be stored safely and transported easily, as the existing energy infrastructure can continue to be used. Carbon dioxide and bicarbonate are interesting carrier surrogates as they are harmless, available in large quantities and inexpensive. The reaction with green hydrogen produces the hydrogen carriers formic acid and formate. Compared to other carriers, these have a lower hydrogen content, but are convincing due to their non-hazardous nature. This is particularly true for formates. If required, the stored hydrogen can be released from the carrier molecules with the help of suitable catalysts and used by reacting with oxygen in fuel cells or by combustion. The storage of green hydrogen utilizing CO₂ and bicarbonate can not only make energy supply safer and more efficient but also make the chemical industry greener.

Venoms are widespread in the animal kingdom. Among the venomous animals, spiders are the most successful representatives and produce the most complex venoms. Based on their large biodiversity it is estimated that spiders comprise about half of all venomous animal species. However, comparatively little is known about their venoms. The development of novel methods of systems biology and biotechnology has rendered the previous impediments in spider venom research. This has not only led to a broader understanding of their evolutionary ecology, but has also had a major translational impact. Valuable molecules derived from spider venoms have been identified and are already used in the bioeconomy, particularly in the fields of biomedicine and agriculture. Furthermore, recent work has shown, that a variety of enzymes can be isolated from spider venom with potential applications in various industrial sectors.

Basically, fungal poisonings can be divided into six groups, some with several subgroups. Fungal toxins may be cytotoxic, neurotoxic, or myotoxic, have specific metabolic, endocrine, or simple gastrointestinal effects, or cause allergic reactions. The structure of toxins is also diverse: rare amino acids, hydrazine derivates, azaridine rings, cyclopropenic acids, steroid derivates, heterocycles, macrocyclic trichothecenes, polysaccharides or octopeptides but also polypeptides with a molecular mass of more than 60.000 daltons can exert a toxic effect as a natural component of a fungus. Neither have all poisonous fungus been discovered yet, nor have all toxins of poisonous fungus been identified or the metabolism elucidated. In addition, there is still increased radioactivity in wild mushrooms today due to the Chernobyl nuclear accident in 1986. However, fungal toxins may play a role as psychotropic or cytostatic drugs in the future.