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Abiotic stress conditions, such as salinity, affect plant development and productivity and threaten the sustainability of agricultural production. Salt has been proven to accumulate in soil and water over time as a result of various anthropogenic activities and climatic changes. Species of the genus Salicornia thrive in the most saline environments and have a wide climatic tolerance. They can be found in a variety of subtropical, oceanic, and continental environments. This study aims to establish Salicornia europaea as a novel source of plant-based compounds that can grow in areas unsuitable for other crops. The morphological and compositional changes in the tissues of S. europaea in different consecutive developmental stages have not been investigated so far. Therefore, a comprehensive study of changes during the lifecycle of S. europaea was carried out, following changes in the plant’s composition, including biomass yield, and soluble and insoluble compounds. For this, plants were cultivated in hydroponics for 15 weeks and harvested weekly to analyze biomass production, to determine soluble and insoluble compounds, protein content, and polyphenols. According to the results, glucan, xylan, and lignin increase with plant age, while water extractives decrease. Protein content is higher in young plants, while flavonoid content depends on the phenological stage, decreasing in the early flowering stage and then increasing as plants enter early senescence. Our results can aid in finding the optimal harvesting stage of S. europaea, depending on the component of interest.

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The phytotoxic mechanisms of patulin (PAT) and penicillic acid (PA) have not been identified unambiguously. This study aims to clarify their effects on thioredoxins (Trxs). Aflatoxin B1 (AFB1), PAT and PA were isolated by solvent extraction and chromatographic techniques from the cultures of Aspergillus flavus Z2 (LC171449), Penicillium vulpinum CM1 and Aspergillus ochraceus EMCC516, respectively. The three mycotoxins showed phytotoxicity to the germination of maize seeds, which was manifested by inhibiting radicle and coleoptile emergence, in addition to their toxic effects on fresh weights and root and shoot lengths. The phytotoxicity of AFB1 and PAT was greater than that of PA. Due to the central roles exhibited by plant Trxs in cellular metabolic activities, they were tested as target proteins for PAT and PA using AFB1 as positive control. In vivo studies showed that the mycotoxins significantly reduced Trx activity measured in the roots and shoots of maize seedlings. PAT showed greater Trx-inhibiting activity than PA and AFB1. In vitro studies of the mycotoxins on Trx y1 (from Arabidopsis thaliana) and thioredoxin reductase (Tr, from rat liver) activities confirm the results of in vivo studies. The inactivation of Trx with PAT and PA was reduced in the presence of glutathione (GSH). Data obtained suggest that lactone mycotoxins are more highly reactive with simple low-molecular-weight thiols (like GSH) than with complex ones (like Trx).

The implementation of digital tools into science education is a major demand of various stakeholders, such as teachers, schools and ministries of education. However, teaching innovations and the introduction of new competences need to be carefully tested and optimized for successful and sustainable application and learning success. Our aim was to develop and establish an easily adaptable teaching unit comprising the aspects of 3D printing from computer-aided modeling to slicing, printing and post-processing, which is linked to curricular learning content. The original teaching concept developed with a small group of students has been adapted to the conditions in large groups and full-size 9th grade school classes. With an increased sample size, it was now possible to investigate and analyze the teaching approach with respect to student’s motivation, learning success as well as the quality and acceptance of the teaching–learning arrangement for designing and 3D printing flower models. The goal of the study was to further optimize the existing teaching tool based on the evaluation of the student experience. While the exploration of this teaching approach ties into the current discourse of innovative biology teaching, the efficacy is evidenced by results that indicate a positive impact on student’s motivation and a high learning success regarding computer-aided modeling and 3D printing. As a result, the teaching-revised concept reported in this article is based on the students’ evaluation and can be provided as well-tested teaching material for schools.

The Angolan population has to deal with a high child mortality rate and various deficiency syndromes due to malnutrition. The diet is mainly based on carbohydrate rich plants, lacking important macro- and micronutrients. Currently the majority of cultivated plants originate from regions outside Africa. Although indigenous edible plant species are incorporated in the African diet, they only play a minor role and are often neglected in agricultural systems. The introduction of nutritive, fast-growing American fruit species as ananas, avocado or guava displace natural growing crops. In recent years the potential of wild edible plants to combat malnutrition, face climate change and deal with existing soil conditions has become of special concern. Leavy vegetables as Amaranthus spec., legumes as cowpea (Vigna unguiculata (L.) Walp.) or fruits as marula (Sclerocarya birrea (A.Rich.) Hochst. or baobab (Adansonia digitata L.) have gained public and commercial interest. However, only a few African edible plant species are cultivated in small plantations (“Fazenda”) or home gardens in the surrounding of villages. Horticultural or nutritional data are often incomplete and not representative. The scientific knowledge even impairs for species which are not cultivated and regarded only as snack or child food by the local population. Such plants as from the genus of chocolate berries (Vitex L.), vine rubber (Landolphia P.Beauv.) or Parinari Aubl. were of special interest for this PhD thesis. Iron and zinc are widely deficient in the diet of the Angolan population and plant products as fruits from Canarium schweinfurthii Engl. or leaves of Crassocephalum rubens (Juss. ex Jacq.) S.Moore can help to combat resulting syndromes. However, the obtained contents of the 43 plant species have to be verified on additional plant material as contents are known to vary. Nevertheless, the results serve as a baseline and represent first insights into the nutritive profile of the respective wild e