An isolation procedure for proteins from duckweed was optimized based on a previously developed method for protein isolation from sugar beet leaves. Optimization included the protocol for disrupting cells and protein recovery. With the optimized protocol, protein was isolated (protein yield 14.2%, RuBisCO yield 27%). The concentrate was off-white and contained 67.2% protein. The isolation procedure resulted in a large enrichment in RuBisCO (from 48% to 92%). Denaturation of duckweed protein concentrate was observed at 62 °C at pH 7, while heating at pH 4 did not show denaturation peaks. Solubility was good far from the iso-electric point and showed a minimum around pH 5. Gelling was better at pH 7 than at pH 4. At pH 7, duckweed gels were much stronger than soy and only slightly weaker compared to egg white protein, while at pH 4 duckweed gel strength was similar to soy and lower than egg white.

Rosmarinus officinalis is an evergreen aromatic plant with important commercial interest as it contains numerous essential oils (composed of terpenoid compounds) and phenolic constituents (natural antioxidant compounds). This work aims at evaluating the concomitant effects of different inorganic and organic fertilization treatments and the subsequent increases in soil nutrient availability on terpenoids and other carbon-based secondary metabolites, e.g., flavonoids and phenolic compounds, in Rosmarinus officinalis leaves. The results showed that, as expected, the structural carbohydrate content (lignocellulosic compounds) in stems was higher in fertilized plants than in controls. Additionally, positive correlations were observed of the absolute amounts of total terpenoids and some single terpenoid compounds with N or P contents in leaves. On the contrary, the phenolic and flavonoid concentrations in all the rosemary plant parts were lower with the fertilization treatments. Indeed, negative correlations between the phenolic compounds (and flavonoids) and N in rosemary leaves were also found. Overall, the results suggest that the terpenoid production’s response to fertilization was due to N, which is essential for protein synthesis and terpene synthase activity, and to P, which is necessary for the synthesis of both terpenoid precursors and ATP and NADPH, also needed for terpenoid synthesis. On the other hand, the basis for the fertilization’s effects on the production of phenolic compounds is the direct nitrogen trade-off between growth and the shikimic acid pathway by which phenolics compounds are synthesized.

SUMMARY In order to evaluate the incidence and aetiology of hypergastrinaemia 53 patients with seropositive rheumatoid arthritis were examined for gastric acid secretion, fasting serum gastrin concentration, circulating parietal cell antibodies, and some parameters of the activity of inflammation of rheumatoid arthritis. The basal and maximum acid output was found to be subnormal in this group (P

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Sugar beet leaves can be a viable and economically interesting source of high‐quality protein for the food industry. We investigated how storage conditions and leaf wounding at harvest affect the content and quality of the soluble protein. After collection, leaves were either stored intact or shredded to mimic wounding induced by commercial leaf harvesters. Leaf material was stored in small volumes at different temperatures to assess leaf physiology or in larger volumes to assess temperature development at different locations in the bins. Protein degradation was more pronounced at higher storage temperatures. Wounding accelerated the degradation of soluble protein at all temperatures. Both wounding and storage at higher temperatures greatly stimulated respiration activity and heat production. At temperatures below 5°C, ribulose‐1,5‐biphosphate carboxylase oxygenase (RuBisCO) in intact leaves was preserved for up to 3 weeks. At temperatures of 30–40°C, RuBisCO degradation occurred within 48 h. Degradation was more pronounced in shredded leaves. In 0.8‐m3 storage bins at ambient temperature, core temperatures rapidly increased, up to 25°C in intact leaves and up to 45°C in shredded leaves within 2–3 days. Immediate storage at 5°C greatly suppressed the temperature increase in intact but not in shredded leaves. The indirect effect of excessive wounding, that is, heat production, is discussed as the pivotal factor responsible for increased degradation of protein. For optimal retention of soluble protein levels and quality in harvested sugar beet leaves, it is advised to minimize wounding and to store the material at temperatures around −5°C. Practical Application To preserve the soluble protein content and quality for at least 3 weeks, sugar beet leaves should be harvested with minimal wounding and stored at temperatures between 1 and 5°C. When aiming to store minimally wounded leaves in larger volumes, it must be ensured that the product temperature in the core of the biomass meets the temperature criterium or the cooling strategy must be adjusted. The principles of minimal wounding and low temperature storage are transferable to other leafy crops that are harvested for food protein.