Consumption of tomato products has been associated with decreased risk of some cancer types, and the tomato antioxidant, lycopene, is thought to play an important role in the observed health effects. In this study, four carotenoids, trans-lycopene, phytofluene, phytoene, and zeta-carotene, were quantified in tomato products. Samples of raw tomatoes, tomato juice after hot break scalder, and final paste were obtained from two different processing plants over two years. Comparison of carotenoid levels throughout processing indicated that lycopene losses during processing of tomatoes into final paste (25-30 degrees Brix) ranged from 9 to 28%. The initial Brix level of the raw tomatoes appeared to influence the amount of lycopene loss that occurred, possibly due to the differences in processing time required to achieve the final desired Brix level of the paste. In general, no consistent changes in the other carotenoids were observed as a function of processing. The antioxidant activity of fresh tomatoes, tomato paste, and three fractions obtained from these products (i.e., aqueous, methanol, and hexane fractions) was also determined. In both a free radical quenching assay and a singlet oxygen quenching assay, significant antioxidant activity was found in both the hexane fraction (containing lycopene) and the methanol fraction, which contained the phenolic antioxidants caffeic and chlorogenic acid. The results suggest that in addition to lycopene, polyphenols in tomatoes may also be important in conferring protective antioxidative effects.

Three triterpenoids, betulinic acid, oleanolic acid, and ursolic acid, were isolated as their methyl esters (treatment with diazomethane) from diethyl ether extracts of almond hulls (Nonpareil variety) using flash chromatography and preparative high-performance liquid chromatography. The triterpenoids, which comprised approximately 1% of the hulls, were characterized using chromatographic and spectroscopic methods. These studies demonstrate that almond hulls are a rich source of these triterpenoids, which have reported anti-inflammatory, anti-HIV, and anti-cancer activities.

starting by 6 h following diazepam injection and returning to approximately control values by 24 h. In situ hybridization showed elevated FGF-2 mRNA labeling in the hippocampal formation, mostly in the pyramidal layer of the CA1 and CA2 subfields and in the dentate gyrus hilar region. These results indicate that diazepam treatment up-regulates FGF-2 expression in select regions of the brain and suggest that GABA may promote neuroplasticity in concert with FGF-2.

We have explored the possibility that the GABA system can influence the expression of FGF-2 in the spinal cord. The GABA agonist diazepam was systemically injected in adult rats, and the expression of FGF-2 was examined in the cervical spinal cord region between 6 h and 7 days post-injection. Results of nuclease protection assays showed increases in FGF-2 mRNA, starting by 6 h and returning to approximately control values by 3 days. There was an increase in the density of FGF-2 immunostained astrocyte-like cells between 6 h and 3 days. Results showing that diazepam up-regulates FGF-2 expression in the spinal cord suggest that GABA may promote neuroplasticity in concert with FGF-2.

Clinical and experimental evidence indicate that physical activity has a positive impact on brain function; however, the molecular bases for how exercise affects the structure and function of the brain are largely unknown. We have investigated the influences of variable periods of voluntary wheel-running on the expression of basic fibroblast growth factor and its mRNA in various brain regions. Nuclease protection assays revealed that the hippocampus was the only region examined exhibiting changes in FGF-2 mRNA as a result of exercise. FGF-2 mRNA increased to reach a peak by the 4th night of wheel-running. FGF-2 immunoreactivity, normally located in the perinuclear area of astrocytes, following exercise became stronger and appeared to spread to the cytoplasm and processes of astrocytes. Quantification of the FGF-2-immunoreactive astrocytes showed an increase in density between 2 and 4 nights of running in discrete regions of the hippocampus. These results demonstrate that exercise regulates FGF-2 expression and suggest that growth factors are likely mediators of the positive effects of exercise on the brain.

As part of a program to control the biosynthesis of Solanum glycoalkaloids in potatoes, we used an HPLC assay to measure the specific alpha-chaconine and alpha-solanine content of greenhouse-grown potato leaves at different stages of maturity. Comparative studies were done with the bromophenol blue titration assay for total glycoalkaloids. We found that foliar glycoalkaloids can be extracted with 5% aqueous acetic acid, that analysis of glycoalkaloids with freeze-dried leaf powders was more reproducible than with fresh leaves, and that the bromophenol colorimetric method gave higher values than HPLC. As little as one leaf from a growing plantlet can be analyzed with the HPLC assay. Large variations in both alpha-chaconine and alpha-solanine contents of fresh leaves suggest that potato foliar glycoalkaloids should be determined by HPLC from freeze-dried rather than fresh leaves.

Exposure of commercial White Rose potatoes to fluorescent light for 20 days induced a time-dependent greening of potato surfaces; an increase in chlorophyll, chlorogenic acid, and glycoalkaloid content (alpha-chaconine and alpha-solanine); and no changes in the content of inhibitors of the digestive enzymes trypsin, chymotrypsin, and carboxypeptidase A. The maximum chlorophyll level of the light-stored potatoes was 0.5 mg/100 g of fresh potato weight. Unstored potatoes contained no chlorophyll. Storing potatoes in the dark did not result in greening or chlorophyll formation. Chlorogenic acid and glycoalkaloid levels of dark-stored potatoes did increase but less than in the light-stored potatoes. In the light, chlorogenic acid concentration increased from 7.1 mg/100 g of fresh potato weight to a maximum of 15.8 mg after greening. The corresponding values for alpha-chaconine are 0.66 and 2.03 mg and for alpha-solanine 0.58 and 1.71, respectively, or an approximately 300% increase for each glycoalkaloid. The trypsin, chymotrypsin, and carboxypeptidase A concentrations, respectively, of about 1000, 375, and 100 units/g of dehydrated potato powder were not changed. Experiments on delay of greening by immersion in water suggest that (a) chlorophyll formation and glycoalkaloid synthesis are unrelated physiological processes and (b) the concentration of chlorophyll is 26 times greater, of chlorogenic acid and glycoalkaloids 7-8 times greater, and of protease inhibitors about 2-3 times lower in the peel of the green potatoes than in the whole tuber. The described compositional changes should help define consequences of potato greening for plant physiology, food quality, and food safety.

Chlorogenic acid is reported to be involved in preharvest defenses of the potato plant against fungi and insects, in postharvest browning, and in after-cooking blackening, all of which affect quality and safety. As part of a program of potato improvement, HPLC and ultraviolet spectroscopy were evaluated to measure the chlorogenic content of commercial and experimental potatoes, of parts of the potato plant, and of processed potato products. HPLC analysis appears to be less satisfactory because chlorogenic acid undergoes a time- and light-dependent change in the methanolic and ethanolic extracts of potatoes used. The decrease of the chlorogenic acid peak on chromatograms was accompanied by a corresponding increase of a new peak. Use of ultraviolet spectrophotometry to estimate chlorogenic acid by contrast appears to be reproducible. Recoveries of spiked samples measured by UV were higher than those measured by HPLC. Thus, our results suggest that the UV method may have advantages over HPLC. Seven varieties of potatoes contained from 10 to 19 mg of chlorogenic acid/100 g of fresh weight. The experimental potato plant NDA 1725 contained 754 mg/100 g of fresh weight for sprouts, 224 mg/100 g for leaves, 26 mg/100 g for roots, and 17 mg/l00 g for tubers. The relative concentrations paralleled those of the glycoalkaloids alpha-chaconine and alpha-solanine. Oven-baked potatoes contained 0% of the original amount of chlorogenic acid, boiled potatoes 35%, and microwaved potatoes 55%. Commercially processed french-fried potatoes, mashed potato flakes, and potato skins contained no chlorogenic acid. The absence of chlorogenic acid was confirmed by ultraviolet spectrophotometry and thin-layer chromatography. The significance of these findings for plant physiology, food quality, and food safety is discussed.

As part of a program to control the biosynthesis of Solanum glycoalkaloids in potatoes, we used a modified extraction-HPLC assay to measure the alpha-chaconine and alpha-solanine content of commercial and new potato varieties, different parts of the potato plant, and commercial potato products. The improved assay was accomplished by extracting, precipitating, and filtering the hot methanol extract through a 0.45-mu-m membrane before HPLC analysis. Recoveries of spiked samples ranged from 89 to 95%. The combined alpha-chaconine and alpha-solanine contents of different parts of the new NDA 1725 potato cultivar (in milligrams per 100 g of fresh weight) were as follows: tubers, 14.7; main stems, 32.0; small stems, 45.6; roots, 86; leaves, 145; and sprouts, 997. The alpha-chaconine content of several other potato cultivars ranged from 1.17 to 13.5 mg/100 g of fresh weight and the corresponding alpha-solanine content from 0.58 to 5.9 mg/100 g of fresh weight. The corresponding values for potato berries were 22.1 and 15.9 mg/100 g of fresh weight, respectively. The total glycoalkaloid content determined by titration with bromophenol blue was 12-30% greater than the sum of alpha-chaconine and alpha-solanine determined by HPLC. The extraction-HPLC method was adapted to measure the glycoalkaloids in freeze-dried french fries (0.08-0.84 mg/ 100 g of product), skins (3.1-20.3 mg/ 100 g of product), potato chips (2.4-10.9 mg/100 g of product), and potato pancake powders (4.5-6.5 mg/100 g of product). The presence of the two glycoalkaloids in commercial foods was also confirmed by thin-layer chromatography. The possible significance of these findings to food safety and plant physiology is discussed.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTEffect of autoclaving and conventional and microwave baking on the ergot alkaloid and chlorogenic acid contents of morning glory (Ipomoea tricolor Cav. cv.) heavenly blue seedsMendel Friedman and Lan DaoCite this: J. Agric. Food Chem. 1990, 38, 3, 805–808Publication Date (Print):March 1, 1990Publication History Published online1 May 2002Published inissue 1 March 1990https://pubs.acs.org/doi/10.1021/jf00093a046https://doi.org/10.1021/jf00093a046research-articleACS PublicationsRequest reuse permissionsArticle Views243Altmetric-Citations17LEARN 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

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTErgot alkaloid and chlorogenic acid content in different varieties of morning glory (Ipomoea spp.) seedsMendel Friedman, Lan Dao, and Michael R. GumbmannCite this: J. Agric. Food Chem. 1989, 37, 3, 708–712Publication Date (Print):May 1, 1989Publication History Published online1 May 2002Published inissue 1 May 1989https://pubs.acs.org/doi/10.1021/jf00087a028https://doi.org/10.1021/jf00087a028research-articleACS PublicationsRequest reuse permissionsArticle Views405Altmetric-Citations16LEARN 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