Assessment of cactus pear leather (pestil) as a new snack food.

In this study, selected nutritional and functional properties of cactus pear and cactus pear leather (pestil) processed with different dryers (oven type and pilot scale tray dryers) were evaluated. For this aim, the fruits collected from three different districts of Turkey were processed and the most suitable region and processing method were investigated. Processing with different dryers had significant (p < 0.05) impact on total acidity, total phenolic content, antioxidant capacity, color and hydroxymethylfurfural values of pestil samples and the best results including antioxidant capacity (66.91-70.25%) and total phenolics (1.79-2.01 g gallic acid equivalent per kg) were obtained with the tray dryer. On the other hand, mineral contents (Na, K, Ca, Mg and Fe) of the products were not significantly (p > 0.05) affected from different dryers. Pestil obtained by tray drying gave the highest rate for the taste. According to the results, the fruits collected from the Aegean region of Turkey were more convenient for processing. Because there is a limited number of studies on this fruit, data provided in the present study may also contribute to further studies.

Effect of High Fructose Corn Sirup on Pancreatic Ductal Adenocarcinoma Induced by Dimethyl Benzantracene (DMBA) in Rats.

Increased risk of pancreatic cancer may be associated with consumption of sugar containing foods. The aim of this study was to evaluate the effect of peach nectar containing high fructose corn sirup (HFCS) consumption in a pancreatic carcinogenesis rat model induced by 7,12-Dimethyl benzanthracene (DMBA). Fifty-day-old male Sprague Dawley rats were fed with peach nectar containing HFCS + chow, peach nectar containing sucrose + chow and only chow. After 8 mo, feeding period, each group was divided into two subgroups, in which the rats were implanted with DMBA and no DMBA (sham). Histologic specimens were evaluated according to the routine tissue processing protocol. The animals with ad libitum access to pn-HFCS, pn-sucrose and chow (only) showed significant differences in chow consumption and glucose level. Necropsy and histopathologic findings showed tumor formation in the entire group treated with DMBA. Excluding one rat in chow group, which was classified as poorly differentiated type, the others were classified as moderately differentiated pancreatic ductal adenocarcinoma (PDAC). This study demonstrated that daily intake of HFCS did not increase body weight and there was no effect of peach nectar consumption on the development of PDAC induced by DMBA in rats.

Sex-specific phenotypes of histone H4 point mutants establish dosage compensation as the critical function of H4K16 acetylation in Drosophila.

Acetylation of histone H4 at lysine 16 (H4K16) modulates nucleosome-nucleosome interactions and directly affects nucleosome binding by certain proteins. In Drosophila, H4K16 acetylation by the dosage compensation complex subunit Mof is linked to increased transcription of genes on the single X chromosome in males. Here, we analyzed Drosophila containing different H4K16 mutations or lacking Mof protein. An H4K16A mutation causes embryonic lethality in both sexes, whereas an H4K16R mutation permits females to develop into adults but causes lethality in males. The acetyl-mimic mutation H4K16Q permits both females and males to develop into adults. Complementary analyses reveal that males lacking maternally deposited and zygotically expressed Mof protein arrest development during gastrulation, whereas females of the same genotype develop into adults. Together, this demonstrates the causative role of H4K16 acetylation by Mof for dosage compensation in Drosophila and uncovers a previously unrecognized requirement for this process already during the onset of zygotic gene transcription.

Botanical and geographical origin of Turkish honeys by selected-ion flow-tube mass spectrometry and chemometrics.

BACKGROUND: Honey has a very important commercial value for producers as a natural product. Honey aroma is formed from the contributions of several volatile compounds, which are influenced by nectar composition, botanical origins, and location. Selected-ion flow-tube mass spectrometry (SIFT-MS) is a technique that quantifies volatile organic compounds simply and rapidly, even in low concentrations. In this study, the headspace concentration of eight monofloral (chestnut, rhododendron, lavender, sage, carob, heather, citrus, and pine) and three multiflower Turkish honeys were analyzed using SIFT-MS. Soft independent modeling of class analogy (SIMCA) was used to differentiate honey samples based on their volatiles. RESULTS: This study focused on 78 volatile compounds, which were selected from previous studies of selected honeys. Very clear distinctions were observed between all honeys. Interclass distances greater than 8 indicate that honeys were significantly different. Methanol and ethanol were abundant in the honeys. Chestnut honey collected from the Yalova region had the highest total concentration of volatiles followed by heather honey and chestnut honey collected from the Düzce region. CONCLUSION: Honeys with different botanical and geographical origins showed differences in their volatile profile based on chemometric analysis. Of the honey samples, methanol, ethanol, acetoin, ethyl acetate, and isobutanoic acid had the highest discriminating power. Methanol and ethanol, and then acetic acid, were the volatiles with the highest concentrations in most honeys. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The histone H3-K27 demethylase Utx regulates HOX gene expression in Drosophila in a temporally restricted manner.

Trimethylation of histone H3 at lysine 27 (H3-K27me3) by Polycomb repressive complex 2 (PRC2) is a key step for transcriptional repression by the Polycomb system. Demethylation of H3-K27me3 by Utx and/or its paralogs has consequently been proposed to be important for counteracting Polycomb repression. To study the phenotype of Drosophila mutants that lack H3-K27me3 demethylase activity, we created Utx(Δ), a deletion allele of the single Drosophila Utx gene. Utx(Δ) homozygotes that contain maternally deposited wild-type Utx protein develop into adults with normal epidermal morphology but die shortly after hatching. By contrast, Utx(Δ) homozygotes that are derived from Utx mutant germ cells and therefore lack both maternal and zygotic Utx protein, die as larvae and show partial loss of expression of HOX genes in tissues in which these genes are normally active. This phenotype classifies Utx as a trithorax group regulator. We propose that Utx is needed in the early embryo to prevent inappropriate instalment of long-term Polycomb repression at HOX genes in cells in which these genes must be kept active. In contrast to PRC2, which is essential for, and continuously required during, germ cell, embryonic and larval development, Utx therefore appears to have a more limited and specific function during development. This argues against a continuous interplay between H3-K27me3 methylation and demethylation in the control of gene transcription in Drosophila. Furthermore, our analyses do not support the recent proposal that Utx would regulate cell proliferation in Drosophila as Utx mutant cells generated in wild-type animals proliferate like wild-type cells.

A comparative study of electrical and conventional pre-treatments for quality assessment of hot air dried green bell pepper.

In this study, the effect of pretreatments (hot water blanching, microwave blanching and ohmic heating) on drying kinetics and quality characteristics of green bell pepper dried at 60, 70 and 80 °C was investigated. Four mathematical models were fitted to experimental data and Logarithmic model was found to be the best for all the samples. Rehydration ability of only ohmic heating pretreated peppers was higher than untreated ones. Total polyphenol (TP) content and antioxidant capacity (AC) of dried peppers varied between 3.21-5.08 mg gallic acid equivalent (GAE)/g dry matter (DM) and 1037.57-2407.40 mmol AAE/100 g DM, respectively. The content of ascorbic acid (AA) in dried samples was in the range of 187.25-722.55 µg/g DM. The bioaccessibility of TP after in-vitro digestion varied from 79.44 to 97.73%. Losses of chlorophyll a and b were very high in all samples compared to fresh ones but the most in control samples.

Optimization and characterization of chestnut shell pigment extract obtained microwave assisted extraction by response surface methodology.

The objective of this study is to find optimum conditions to valorize chestnut shell bioactive compounds with coloring pigments through microwave-assisted extraction. With this aim, response surface methodology with central composite design was used. Microwave power (800 W), extraction time (12 min) and solvent concentration (NaOH: 0.115 mol/L) were determined as the optimum conditions to maximize the responses like color value, total phenolic content and total antioxidant capacity. In the optimized extract (OE), characterization of brown melanin like pigments were assessed by Spectrophotometer, Fourier Transform Infrared Spectrometer and major phenolics were identified as; gallic acid, ellagic acid, protocatechuic acid, catechin, and epicatechin as 0.53, 0.48, 0.46, 0.46, 0.14 mg/g dried weight (dw) by High Performance Liquid Chromatography, respectively. In terms of antibacterial activity, OE inhibited the growth of Staphylococcus aureus. Consequently, chestnut shells were successfully processed into natural coloring agents that were possessing strong brown color properties as well as high bioactive potential.

Histone Demethylase Activity of Utx Is Essential for Viability and Regulation of HOX Gene Expression in Drosophila.

The trimethylation of histone H3 at lysine 27 (H3K27me3) by Polycomb Repressive Complex 2 (PRC2) is essential for the repression of Polycomb target genes. However, the role of enzymatic demethylation of H3K27me3 by the KDM6-family demethylases Utx, Uty, and JmjD3 is less clear. Studies in both mice and worms led to the proposal that KDM6 proteins, but not their H3K27me3 demethylase activity, is critical for normal development. Here, we investigated the requirement of the demethylase activity of the single KDM6 family member Utx in Drosophila We generated Drosophila expressing a full-length but catalytically inactive Utx protein and found that these mutants show the same phenotypes as animals lacking the Utx protein. Specifically, animals lacking maternally deposited active Utx demethylase in the early embryo show stochastic loss of HOX gene expression that appears to be propagated in a clonal fashion. This suggests that Utx demethylase activity is critical for the removal of ectopic H3K27 trimethylation from active HOX genes during the onset of zygotic gene transcription, and thereby prevents the inappropriate installment of long-term repression by Polycomb. Conversely, maternally deposited catalytically active Utx protein suffices to permit animals that lack zygotic expression of enzymatically active Utx to develop into morphologically normal adults, which eclose from the pupal case but die shortly thereafter. Utx demethylase activity is therefore also essential to sustain viability in adult flies. Together, these analyses identify the earliest embryonic stages and the adult stage as two phases during the Drosophila life cycle that critically require H3K27me3 demethylase activity.

A histone mutant reproduces the phenotype caused by loss of histone-modifying factor Polycomb.

Although many metazoan enzymes that add or remove specific modifications on histone proteins are essential transcriptional regulators, the functional significance of posttranslational modifications on histone proteins is not well understood. Here, we show in Drosophila that a point mutation in lysine 27 of histone H3 (H3-K27) fails to repress transcription of genes that are normally repressed by Polycomb repressive complex 2 (PRC2), the methyltransferase that modifies H3-K27. Moreover, differentiated H3-K27 mutant cells show homeotic transformations like those seen in PRC2 mutant cells. Taken together, these analyses demonstrate that H3-K27 is the crucial physiological substrate that PRC2 modifies for Polycomb repression.

A study of fortification of lemonade with herbal extracts

Abstract The aim of the present work was to design new beverages using lemonade and some herbal extracts (linden, heather, green tea, lemon verbena, clove, peppermint, ginger and mate) rich in vitamin C and flavonoids. The linden-added lemonade showed the highest value (597.9 mg/kg) for ascorbic acid content, whereas the lemon verbena-added lemonade showed the lowest value (486.04 mg/kg). The amount of saccharose was changed by 11.07-11.58%, the glucose by 1.11-1.62% and the fructose between 11.07-11.58% in the beverages. K, Na, Mg and P values in the lemonades were determined in the range of 178.83-210.98 mg/kg, 33.75-39.13 mg/kg, 22.37-27.89 mg/kg and 7.22-10.04 mg/kg, respectively. The total phenolic content in the samples changed between 315.11-397.57 mg GAE/100 g. When the samples were analyzed for antioxidant activity, FRAP (17.13-26.79 µmol trolox/mL) and ABTS (16.91-25.38 µmol trolox/mL) methods gave higher results than the DPPH (14.88-17.72 µmol trolox/mL) method. Linden-, ginger- and peppermint-added lemonades, which had been found to be rich in total phenolic compounds and ascorbic acid, showed higher antioxidant activity than the control sample. Overall, the most preferred lemonades were heather- and ginger-added beverages and the control sample. Mate-added lemonade was the least preferred.