Levels of katahdinone (solavetivone), lubimin, rishitin, and phytuberin, sesquiterpenoid stress metabolites of white potato (Solanum tuberosum), were monitored in tuber slices which were challenged with an extract of Phytophthora infestans and incubated under controlled atmospheres. A mixture of ethylene in air enhanced stress metabolite production. This enhancement was amplified by higher partial pressures of oxygen. Stress metabolite production was inhibited by salicylhydroxamic acid. These results suggest the involvement of cyanide-resistant respiration in the production of potato stress metabolites, compounds which may serve as phytoalexins.
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTVolumetric and Gravimetric Analytical Methods for Organic CompoundsW. T. Smith, W. F. Wagner, and J. M. PattersonCite this: Anal. Chem. 1956, 28, 4, 706–714Publication Date (Print):April 1, 1956Publication History Published online1 May 2002Published inissue 1 April 1956https://pubs.acs.org/doi/10.1021/ac60112a020https://doi.org/10.1021/ac60112a020research-articleACS PublicationsRequest reuse permissionsArticle Views95Altmetric-Citations1LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
The effects in young male rats of 10 edible oils and fats on total hepatic lipids and serum cholesterol have been compared in the presence of various amounts of dietary choline. The fats were incorporated at the 20% level in a basal hypolipotropic diet (15% protein) free from cholesterol. The diets were fed for 3 weeks. Food intake and efficiency of conversion of food to body tissue were similar with the different fats when choline was adequate; diets containing corn oil were possibly slightly less efficient. The fat-free basal ration caused heavy mortality from hemorrhagic kidney lesions. The survival rate was improved by all fats except Primex or beef fat. Coconut oil gave complete protection against renal damage.There was a negligible difference in the tendency for different fats to cause deposition of total hepatic lipids, although sunflower seed oil produced less accumulation at lower dosages of choline than did the others. The fats did differ in the extent to which they promoted deposition of cholesteryl esters.No significant differences were found in the total cholesterol of serum of rats fed the different fats. The decrease in serum cholesterol that occurs in the absence of dietary choline does not appear to be influenced by the nature of the dietary fat.
We report the detection of water vapor associated with main-belt comet 358P/PANSTARRS on UT 2024 January 8-9 using the NIRSPEC instrument aboard JWST. We derive a water production rate of Q(H2O)=(5.0+/-0.2)x10^25 molecules/s, marking only the second direct detection of sublimation products of any kind from a main-belt comet, after 238P/Read. Similar to 238P, we find a remarkable absence of hypervolatile species, finding Q(CO2)<7.6x10^22 molecules/s, corresponding to Q(CO2)/Q(H2O)<0.2%. Upper limits on CH3OH and CO emission are also estimated. Photometry from ground-based observations show that the dust coma brightened and faded slowly over ~250 days in 2023-2024, consistent with photometric behavior observed in 2012-2013, but also indicate a ~2.5x decline in the dust production rate between these two periods. Dynamical dust modeling shows that the coma's morphology as imaged by JWST's NIRCAM instrument on 2023 November 22 can be reproduced by asymmetric dust emission from a nucleus with a mid-range obliquity (~80 deg) with a steady-state mass loss rate of ~0.8 kg/s. Finally, we find similar Afrho-to-gas ratios of log10(Afrho/Q(H2O))=-24.8+/-0.2 for 358P and log10(Afrho/QH2O)=-24.4+/-0.2 for 238P, suggesting that Afrho could serve as an effective proxy for estimating water production rates in other active main-belt comets. The confirmation of water vapor outgassing in both main-belt comets observed by JWST to date reinforces the use of recurrent activity near perihelion as an indicator of sublimation-driven activity in active asteroids.
Dose–response curves have been obtained showing the effects, in weanling rats, of graded doses of choline, betaine, and methionine, respectively, when added to a hypolipotropic diet. A comparison of the lipotropic activity made on the steep portions of the dose–response curves showed that at all liver fat values from normal to 27%, the ratio of betaine to choline necessary to produce a given level of fat was 3: 1. Essentially similar ratios were observed in the prevention of hemorrhagic kidney lesions and in the stimulation of growth. Methionine, at the lower doses, was as effective as betaine, on a molar basis, in maintaining a given level of liver fat. However, the higher levels of methionine were not as efficient. Methionine at the highest dosage used did not bring the liver fat entirely within the normal range.
