Plants make specialized bioactive metabolites to defend themselves against attackers. The conserved control mechanisms are based on transcriptional activation of the respective plant species-specific ...biosynthetic pathways by the phytohormone jasmonate. Knowledge of the transcription factors involved, particularly in terpenoid biosynthesis, remains fragmentary. By transcriptome analysis and functional screens in the medicinal plant Catharanthus roseus (Madagascar periwinkle), the unique source of the monoterpenoid indole alkaloid (MIA)-type anticancer drugs vincristine and vinblastine, we identified a jasmonate-regulated basic helixâloopâhelix (bHLH) transcription factor from clade IVa inducing the monoterpenoid branch of the MIA pathway. The bHLH iridoid synthesis 1 (BIS1) transcription factor transactivated the expression of all of the genes encoding the enzymes that catalyze the sequential conversion of the ubiquitous terpenoid precursor geranyl diphosphate to the iridoid loganic acid. BIS1 acted in a complementary manner to the previously characterized ethylene response factor Octadecanoid derivative-Responsive Catharanthus APETALA2-domain 3 (ORCA3) that transactivates the expression of several genes encoding the enzymes catalyzing the conversion of loganic acid to the downstream MIAs. In contrast to ORCA3 , overexpression of BIS1 was sufficient to boost production of high-value iridoids and MIAs in C. roseus suspension cell cultures. Hence, BIS1 might be a metabolic engineering tool to produce sustainably high-value MIAs in C. roseus plants or cultures.
Significance Terpenoids are the largest group of plant-specialized metabolites and include many valuable bioactive compounds, such as the blockbuster anticancer drugs vincristine and vinblastine, that are monoterpenoid indole alkaloids from the medicinal plant Catharanthus roseus (Madagascar periwinkle). A master regulator was discovered that activates the biosynthesis of the iridoids, the monoterpenoid precursors of vinblastine and vincristine, and the rate-limiting branch in their biosynthetic pathway. This master regulator can be used to boost production of iridoids and monoterpenoid indole alkaloids in C. roseus cell cultures and thus represents an interesting tool for the metabolic engineering of the sustainable production of these high-value compounds in cultures of the endogenous plant species.
Activation of lipid metabolism is an early event in carcinogenesis and a central hallmark of many cancers. However, the precise molecular composition of lipids in tumors remains generally poorly ...characterized. The aim of the present study was to analyze the global lipid profiles of breast cancer, integrate the results to protein expression, and validate the findings by functional experiments. Comprehensive lipidomics was conducted in 267 human breast tissues using ultraperformance liquid chromatography/ mass spectrometry. The products of de novo fatty acid synthesis incorporated into membrane phospholipids, such as palmitate-containing phosphatidylcholines, were increased in tumors as compared with normal breast tissues. These lipids were associated with cancer progression and patient survival, as their concentration was highest in estrogen receptor-negative and grade 3 tumors. In silico transcriptomics database was utilized in investigating the expression of lipid metabolism related genes in breast cancer, and on the basis of these results, the expression of specific proteins was studied by immunohistochemistry. Immunohistochemical analyses showed that several genes regulating lipid metabolism were highly expressed in clinical breast cancer samples and supported also the lipidomics results. Gene silencing experiments with seven genes ACACA (acetyl-CoA carboxylase α), ELOVL1 (elongation of very long chain fatty acid-like 1), FASN (fatty acid synthase), INSIG1 (insulin-induced gene 1), SCAP (sterol regulatory element-binding protein cleavage-activating protein), SCD (stearoyl-CoA desaturase), and THRSP (thyroid hormone-responsive protein) indicated that silencing of multiple lipid metabolism-regulating genes reduced the lipidomic profiles and viability of the breast cancer cells. Taken together, our results imply that phospholipids may have diagnostic potential as well as that modulation of their metabolism may provide therapeutic opportunities in breast cancer treatment.
Black soldier fly larvae (BSFL; Hermetia illucens) are subjected to a conventional fishmeal process, or room‐temperature formic acid hydrolysis, and lipid yield and composition between the two ...processes compared. Acid hydrolysis of BSFL results in higher protein yield in the meal and higher oil yield. Oils separated after acid hydrolysis have a lower trilaurin content (triacyglycerol with lauric acid (12:0) in all sn‐positions) and a lower melting point (23 °C) compared to oils separated after conventional (fishmeal) processing (26 °C). Further reduction of trilaurin content and melting point (20 °C) are achieved by dry‐fractionation (winterization) of the oil.
Practical Applications: Fractionation of black soldier fly larvae oil could yield products with targeted levels of trilaurin and melting points adapted to different applications in feeds, foods, and cosmetics.
Trilaurin content in black soldier fly larvae (BSFL) oil from conventional down‐stream process (BSFL‐O), from acid hydrolysis (BSFL‐EO), and olein‐ and stearin phases after winterization. Average ± standard deviation; n = 2. Black line indicates melting point of the oils.
Euglena gracilis, a photosynthetic protist, produces protein, unsaturated fatty acids, wax esters, and a unique β-1,3-glucan called paramylon, along with other valuable compounds. The cell ...composition of E. gracilis was investigated in this study to understand how light and organic carbon (photo-, mixo- and heterotrophic conditions) affected growth and cell composition (especially lipids). Comparisons were primarily carried out in cultures grown at 23 °C, but the effect of growth at higher temperatures (27 or 30 °C) was also considered.
Specific growth rates were slightly lower when E. gracilis was grown on glucose in either heterotrophic or mixotrophic conditions than when grown photoautotrophically, although the duration of exponential growth was longer. Temperature determined the rate of exponential growth in all cultures, but not the linear growth rate during light-limited growth in phototrophic conditions. Temperature had less effect on cell composition.
Although E. gracilis was not expected to store large amounts of paramylon when grown phototrophically, we observed that phototrophic cells could contain up to 50% paramylon. These cells contained up to 33% protein and less than 20% lipophilic compounds, as expected. The biomass contained about 8% fatty acids (measured as fatty acid methyl esters), most of which were unsaturated. The fatty acid content of cells grown in mixotrophic conditions was similar to that observed in phototrophic cells, but was lower in cells grown heterotrophically. Heterotrophic cells contained less unsaturated fatty acids than phototrophic or mixotrophic cells. α-Linolenic acid was present at 5 to 18 mg g-1 dry biomass in cells grown in the presence of light, but at < 0.5 mg g-1 biomass in cells grown in the dark. Eicosapentaenoic and docosahexaenoic acids were detected at 1 to 5 mg g-1 biomass. Light was also important for the production of vitamin E and phytol.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Proof of Concept for Cell Culture-Based Coffee Aisala, Heikki; Kärkkäinen, Elviira; Jokinen, Iina ...
Journal of agricultural and food chemistry,
11/2023, Letnik:
71, Številka:
47
Journal Article
Recenzirano
Odprti dostop
The global coffee production is facing serious challenges including land use, climate change, and sustainability while demand is rising. Cellular agriculture is a promising alternative to produce ...plant-based commodities such as coffee, which are conventionally produced by farming. In this study, the complex process of drying and roasting was adapted for bioreactor-grown coffee cells to generate a coffee-like aroma and flavor. The brews resulting from different roasting regimes were characterized with chemical and sensory evaluation-based approaches and compared to conventional coffee. Roasting clearly influenced the aroma profile. In contrast to conventional coffee, the dominant odor and flavor attributes were burned sugar-like and smoky but less roasted. The intensities of bitterness and sourness were similar to those of conventional coffee. The present results demonstrate a proof of concept for a cellular agriculture approach as an alternative coffee production platform and guide future optimization work.
Scope
Quinic acid in its free form is broadly abundant in plants, and can accumulate in copious amounts in coffee, tea, and certain fruits. However, it has been mostly studied as chlorogenic acid, an ...ester of caffeic and quinic acids. When chlorogenic acid reaches the colon, it is hydrolyzed by microbial esterases releasing caffeic and quinic acids. While biotransformation of chlorogenic and caffeic acids have been elucidated by in vitro and in vivo studies, the gut metabolism of quinic acid has been so far overlooked.
Methods and Results
U‐13C‐Quinic acid is submitted to a colonic model using human fecal microbiota for assessing its metabolic fate. The metabolite profiles formed along microbial biotransformation are monitored by a combined metabolomics approach, using both 2D GC– and ultra‐HPLC–MS. Six metabolic intermediates are identified by incorporation of isotopic label.
Conclusion
Two parallel degradation pathways could be proposed: (1) an oxidative route, leading to aromatization and accumulation of protocatechuic acid, and a (2) reductive route, including dehydroxylation to cyclohexane carboxylic acid. Elucidating the biotransformation of food bioactives by the gut microbiota is of relevance for understanding nutrition, interindividual variability and potential effects on human metabolism.
Quinic acid (QA) is an abundant compound in certain foods, e.g., coffee and cranberries. In this study, an in vitro colonic model, using human fecal suspension, assess the gut metabolism of U‐13C‐QA. Using GC– and LC–MS‐based metabolomics, six metabolic intermediates are selectively identified. Elucidating the gut microbial biotransformation of food bioactives, such as QA, is of relevance for understanding nutrition, interindividual variability, and potential effects on human metabolism.
The risk determinants of type 1 diabetes, initiators of autoimmune response, mechanisms regulating progress toward beta cell failure, and factors determining time of presentation of clinical diabetes ...are poorly understood. We investigated changes in the serum metabolome prospectively in children who later progressed to type 1 diabetes. Serum metabolite profiles were compared between sample series drawn from 56 children who progressed to type 1 diabetes and 73 controls who remained nondiabetic and permanently autoantibody negative. Individuals who developed diabetes had reduced serum levels of succinic acid and phosphatidylcholine (PC) at birth, reduced levels of triglycerides and antioxidant ether phospholipids throughout the follow up, and increased levels of proinflammatory lysoPCs several months before seroconversion to autoantibody positivity. The lipid changes were not attributable to HLA-associated genetic risk. The appearance of insulin and glutamic acid decarboxylase autoantibodies was preceded by diminished ketoleucine and elevated glutamic acid. The metabolic profile was partially normalized after the seroconversion. Autoimmunity may thus be a relatively late response to the early metabolic disturbances. Recognition of these preautoimmune alterations may aid in studies of disease pathogenesis and may open a time window for novel type 1 diabetes prevention strategies.
Hepatic Stearoyl-CoA Desaturase (SCD)-1 Activity and Diacylglycerol but Not Ceramide Concentrations Are Increased in the Nonalcoholic
Human Fatty Liver
Anna Kotronen 1 2 ,
Tuulikki Seppänen-Laakso 3 ...,
Jukka Westerbacka 1 ,
Tuula Kiviluoto 4 ,
Johanna Arola 5 ,
Anna-Liisa Ruskeepää 3 ,
Matej Orešič 3 and
Hannele Yki-Järvinen 1
1 Department of Medicine, Division of Diabetes, Helsinki, Finland
2 Minerva Medical Research Institute, Helsinki, Finland
3 VTT Technical Research Centre of Finland, Espoo, Finland
4 Department of Surgery, University of Helsinki, Helsinki, Finland
5 Department of Pathology, University of Helsinki and HUSLAB, Helsinki, Finland
Corresponding author: Anna Kotronen, anna.kotronen{at}helsinki.fi
Abstract
OBJECTIVE— To determine whether 1 ) hepatic ceramide and diacylglycerol concentrations, 2 ) SCD1 activity, and 3 ) hepatic lipogenic index are increased in the human nonalcoholic fatty liver.
RESEARCH DESIGN AND METHODS— We studied 16 subjects with ( n = 8) and without ( n = 8) histologically determined nonalcoholic fatty liver (NAFL + and NAFL − ) matched for age, sex, and BMI. Hepatic concentrations of lipids and fatty acids were quantitated using ultra-performance
liquid chromatography coupled to mass spectrometry and gas chromatography.
RESULTS— The absolute (nmol/mg) hepatic concentrations of diacylglycerols but not ceramides were increased in the NAFL + group compared with the NAFL − group. The livers of the NAFL + group contained proportionally less long-chain polyunsaturated fatty acids as compared with the NAFL − group. Liver fat percent was positively related to hepatic stearoyl-CoA desaturase 1 (SCD1) activity index ( r = 0.70, P = 0.003) and the hepatic lipogenic index ( r = 0.54, P = 0.030). Hepatic SCD1 activity index was positively related to the concentrations of diacylglycerols ( r = 0.71, P = 0.002) but not ceramides ( r = 0.07, NS).
CONCLUSIONS— We conclude that diacylglycerols but not ceramides are increased in NAFL. The human fatty liver is also characterized by depletion
of long polyunsaturated fatty acids in the liver and increases in hepatic SCD1 and lipogenic activities.
Footnotes
Published ahead of print at http://diabetes.diabetesjournals.org on 24 October 2008.
M.O. and H.Y.-J. share senior authorship of this study.
Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work
is not altered. See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details.
The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore
be hereby marked “advertisement” in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.
Accepted October 17, 2008.
Received August 5, 2008.
DIABETES
Sarraceniaceae is a New World carnivorous plant family comprising three genera: Darlingtonia, Heliamphora, and Sarracenia. The plants occur in nutrient-poor environments and have developed ...insectivorous capability in order to supplement their nutrient uptake. Sarracenia flava contains the alkaloid coniine, otherwise only found in Conium maculatum, in which its biosynthesis has been studied, and several Aloe species. Its ecological role and biosynthetic origin in S. flava is speculative. The aim of the current research was to investigate the occurrence of coniine in Sarracenia and Darlingtonia and to identify common constituents of both genera, unique compounds for individual variants and floral scent chemicals. In this comprehensive metabolic profiling study, we looked for compound patterns that are associated with the taxonomy of Sarracenia species. In total, 57 different Sarracenia and D. californica accessions were used for metabolite content screening by gas chromatography-mass spectrometry. The resulting high-dimensional data were studied using a data mining approach. The two genera are characterized by a large number of metabolites and huge chemical diversity between different species. By applying feature selection for clustering and by integrating new biochemical data with existing phylogenetic data, we were able to demonstrate that the chemical composition of the species can be explained by their known classification. Although transcriptome analysis did not reveal a candidate gene for coniine biosynthesis, the use of a sensitive selected ion monitoring method enabled the detection of coniine in eight Sarracenia species, showing that it is more widespread in this genus than previously believed.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Ceramides may mediate saturated fat–induced insulin resistance, but there are no data comparing ceramide concentrations between human tissues. We therefore performed lipidomic analysis of human ...subcutaneous (SCfat) and intra‐abdominal (IAfat) adipose tissue, the liver, and serum in eight subjects. The liver contained (nmol/mg tissue) significantly more ceramides (1.5–3‐fold), sphingomyelins (7–8‐fold), phosphatidylethanolamines (10–11‐fold), lysophosphatidylcholines (7–12‐fold), less ether‐linked phosphatidylcholines (2–2.5‐fold) but similar amounts of diacylglycerols as compared to SCfat and IAfat. The amounts of ceramides and their synthetic precursors, such as palmitic (16:0) free fatty acids and sphingomyelins, differed considerably between the tissues. The liver contained proportionally more palmitic, stearic (18:0), and long polyunsaturated fatty acids than adipose tissues. Stearoyl‐CoA desaturase 1 (SCD1) activity reflected by serum, estimated from the 16:1/16:0‐ratio, was closely related to that in the liver (r = 0.86, P = 0.024) but not adipose tissues. This was also true for estimated elongase (18:1/16:1, r = 0.89, P = 0.01), and Δ5 (20:4/20:3, r = 0.89, P = 0.012) and Δ6 (18:3n‐6/18:2, r = 1.0, P < 0.001) desaturase activities. We conclude that the human liver contains higher concentrations of ceramides and saturated free fatty acids than either SCfat or IAfat.
PDF
