University of Hohenheim

About: University of Hohenheim is a education organization based out in Stuttgart, Germany. It is known for research contribution in the topics: Population & Soil water. The organization has 8585 authors who have published 16406 publications receiving 567377 citations.

Protein concentrate from Jatropha curcas screw-pressed seed cake and toxic and antinutritional factors in protein concentrate

Abstract: BACKGROUND: Jatropha curcas seeds are highly toxic to livestock The presence of phorbol esters and antinutrients such as trypsin inhibitor, lectin and phytate and the high level of shells in the seed cake prevent its use in animal diets Using the principle of isoelectric precipitation, the conditions for preparation of the protein concentrate from oil-containing seed cake and defatted seed cake were optimised and the contents of phorbol esters and antinutrients were determined RESULTS: The recovery of protein concentrate was highest when the proteins from the seed cakes were solubilised at pH 11 for 1 h at 60 ◦ C and the precipitation of these proteins was done by lowering the pH to 4 Under these conditions, over 53% of the total proteins present in the seed cakes were recovered in the protein concentrates The protein contents in the protein concentrates obtained from the oil-containing seed cake and defatted seed cake were 760 and 820 g kg −1 respectively Substantial amounts of phorbol esters were present in the protein concentrates (086–148 mg g −1 ) Trypsin inhibitor was present at an approximately tenfold higher level in the protein concentrates than in the seed cakes Lectin and phytate were also present at high levels, but their levels were lower than in the seed cakes Tannins were present in negligible amounts CONCLUSION: To make the protein concentrate from Jatropha seed cake fit for use as an ingredient in livestock feed, phorbol esters must be removed and trypsin inhibitor and lectin inactivated by heat treatment The adverse effects of phytate could be mitigated by addition of phytase in the diet  2008 Society of Chemical Industry

Significance of flower and fruit thinning on fruit quality

Abstract: The effects of mechanical or chemical flower and fruit thinning on fruitquality were primarily by altering crop load. However, there were alsodirect effects of thinning agents. Fruit size was directly related tothinning intensity. In addition to crop load, age of wood, flower budquality, competition within clusters and canopy were important factorsaffecting the response to thinning. Short- and long-term thinningstudies identified two groups of quality components: Group 1characteristics include size, colour, skin performance, firmness andsugar and acid content of the fruit. Group 2 characteristics wererepresented by inorganic components, especially calcium and potassiumwhich are implicated in the susceptibility of fruit to physiologicaldisorders. While group 1 characteristics were improved by increasingthinning intensity, storability of the fruit was better at high than atlow crop loads. Therefore, a compromise between all quality requirementsmust be found for a good economic return. Establishing the trends ofthinning on the different quality parameters can help to select athinning strategy for local or regional conditions typically beingdetermined by growing and market conditions.

Physiological and pathophysiological functions of intestinal mast cells

Abstract: The normal gastrointestinal (GI) mucosa is equipped with mast cells that account for 2-3% of lamina propria cells under normal conditions. Mast cells are generally associated with allergic disease, and indeed, food allergy that manifests in the GI tract is usually mast cell dependent. On the other hand, mast cells have a number of physiological functions in the GI tract, namely regulatory functions such as control of blood flow and coagulation, smooth muscle contraction and peristalsis, and secretion of acid, electrolytes, and mucus by epithelial cells. One of the most intriguing functions of intestinal mast cells is their role in host defense against microbes like bacteria, viruses, or parasites. Mast cells recognize microbes by antibody-dependent mechanisms and through pattern-recognition receptors. They direct the subsequent immune response by attracting both granulocytes and lymphocytes to the site of challenge via paracrine cytokine release. Moreover, mast cells initiate, by releasing proinflammatory mediators, innate defense mechanisms such as enhanced epithelial secretion, peristalsis, and alarm programs of the enteric nervous This initiation can occur in response to a primary contact to the microbe or other danger signals, but becomes much more effective if the triggering antigen reappears and antibodies of the IgE or IgG type have been generated in the meantime by the specific immune system. Thus, mast cells operate at the interface between innate and adaptive immune responses to enhance the defense against pathogens and, most likely, the commensal flora. In this respect, it is important to note that mast cells are directly involved in controlling the function of the intestinal barrier that turned out to be a crucial site for the development of infectious and immune-mediated diseases. Hence, intestinal mast cells perform regulatory functions to maintain tissue homeostasis, they are involved in host defense mechanisms against pathogens, and they can induce allergy once they are sensitized against foreign antigens. The broad spectrum of functions makes mast cells a fascinating target for future pharmacological or nutritional interventions.

Relationship between Hydrophobicity and Antioxidant Ability of “Phenolipids” in Emulsion: A Parabolic Effect of the Chain Length of Rosmarinate Esters

Abstract: The polar paradox predicts that hydrophobic antioxidants are more active in emulsions than their hydrophilic homologues, thus assuming a linear dependency between hydrophobicity and antioxidant capacity. In contrast, we formulate in this paper an alternative hypothesis assuming a possible nonlinear dependency. To verify this so-called "nonlinear hypothesis", the antioxidant capacity of a homologous series of rosmarinic acid and its alkyl esters (methyl, butyl, octyl, dodecyl, hexadecyl, octadecyl, and eicosyl) was evaluated using a newly developed conjugated autoxidizable triene (CAT) assay. It appeared that the antioxidant capacity increases as the alkyl chain is lengthened, with a maximum for the octyl chain, after which further chain extension leads to a collapse in antioxidant capacity. This nonlinear effect was discussed in relation to the "cutoff effect" generally observed in studies using cultured cells. This new hypothesis may provide a better understanding of the antioxidant behavior of phenolics in emulsion which is a key to develop new antioxidant strategies to protect lipid substrates from oxidation. Moreover, the lipophilization with medium chain appeared as a promising way to enhance the antioxidant capacity of phenolics since octyl rosmarinate was three times more effective than rosmarinic acid which is already one of the most powerful known phenolic antioxidant. Finally, this work paves the way for systematic investigation of the chain length effect to design new "phenolipids" in a rational fashion.