scholarly journals Phloridzin as a marker for evaluation of fruit products authenticity

2021 ◽  
Vol 39 (No. 1) ◽  
pp. 49-57
Author(s):  
Magdaléna Hrubá ◽  
Josef Baxant ◽  
Helena Čížková ◽  
Veronika Smutná ◽  
František Kovařík ◽  
...  

Abstract: Phloridzin (phloretin-2'-O-glucoside) is a phenolic compound characteristic of the genus Malus. This study aimed to evaluate phloridzin as a marker of undeclared addition of apples in fruit products. To test this proposal, the heat and oxidation stability of phloridzin was firstly confirmed. Then the distribution and variability of phloridzin in apples were studied, showing no difference between the tested apple varieties (Golden Delicious, Granny Smith, Rubin and Champion) but a significant difference in phloridzin content in seeds (2 380 ± 755 mg kg<sup>–1</sup>) compared to peel, flesh and core, which contained less than 70 mg kg<sup>–1</sup>. The effects of different stages of apple purée production at an industrial scale were also investigated. The kinetics of phloridzin diffusion from seeds to apple homogenate played an important role in the final phloridzin content in 16 analysed apple purées (26–39 mg kg<sup>–1</sup>). Finally, the survey of phloridzin content in 31 fruit products in the market was carried out. Phloridzin was also measured in eight jams and fillings which did not declare the presence of apples on their labels; findings from 2 to 6 mg kg<sup>–1 </sup>indicate the addition of apples from 5% to 20%. It was confirmed that phloridzin appears to be a suitable marker for detecting the undeclared presence of apples, which are a cheap substitute for the declared fruit types.

2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Laurent-Emmanuel Monfoulet ◽  
Caroline Buffiere ◽  
Geoffrey Istas ◽  
Claire Dufour ◽  
Carine le Bourvelec ◽  
...  

AbstractFood matrix is known to interact with some dietary constituents and microconstituents during digestion. These interactions may potentially affect the metabolism and bioavailability of some compounds, and as a consequence modulate their biological effects. In this context, the aim of this study was to determine the effect of apple food matrix on the bioavailability of flavan-3-ols and on the ability of these compounds to modulate the nutrigenomic response to a high fat challenge in minipigs.Adult male Yucatan minipigs (n = 5) were assigned to a random treatment sequence of high-fat meals non supplemented or supplemented with 250 g of raw apple, 250 g of apple puree or 1.4 g of apple polyphenols extract, with a 7-days washout period between each treatment. Each supplementation provided 155 mg flavan-3-ol monomers. At each treatment period, fasting- and 1h-, 2h-, 3h-postprandial blood samples were collected, and the concentration in flavan-3-ol monomers was measured on hydrolyzed serum, using UPLC-Q-TOF MS. The ability of apple-derived products to modulate the postprandial gene expression profile was assessed and compared in circulating PBMCs collected at 3 h after consumption of the four tested meals using a microarray analysis.Results show that the apple matrix did not affect the kinetic of the postprandial absorption of flavan-3-ol monomers. The total flavan-3-ols concentrations measured at peak were significantly higher in the extract (x1.75), suggesting an impact of the apple matrix on flavan-3-ols absorption. However, no significant difference in total flavanols was observed between raw apple and apple puree.Principal Component Analysis of the microarray data from PBMCs identified three distinct clusters of gene expression patterns: one corresponding to gene expression profiles after the high-fat meal, one for meal supplemented with raw apples or apple puree, and a third cluster for meal supplemented with polyphenol extract. A set of 309 genes was identified as differentially expressed by apple-derived products compared to high-fat meal alone, including 93 modulated with the three apple products. The variations in gene expression were similar for only 75% of the 93 genes, suggesting that the apple matrix affects the nutrigenomic response to flavan-3-ols. A bioinformatics analysis revealed that genes affected by apple-derived products are involved in inflammation and leukocyte transendothelial migration, suggesting a beneficial impact of apple-derived products.In conclusion, these results raise awareness for considering the impact of food matrix on the biological responsiveness of polyphenols in future nutritional studies.


2015 ◽  
Vol 24 (1) ◽  
pp. 51-59 ◽  
Author(s):  
Oana-Viorela Nistor ◽  
Nicoleta Stãnciuc ◽  
Doina Georgeta Andronoiu ◽  
Gabriel Dãnuţ Mocanu ◽  
Elisabeta Botez

1982 ◽  
Vol 48 (02) ◽  
pp. 211-216 ◽  
Author(s):  
V M Haver ◽  
A R L Gear

SummaryPlatelet heterogeneity has been studied with a technique called functional fractionation which employs gentle centrifugation to yield subpopulations (“reactive” and “less-reactive” platelets) after exposure to small doses of aggregating agent. Aggregation kinetics of the different platelet populations were investigated by quenched-flow aggregometry. The large, “reactive” platelets were more sensitive to ADP (Ka = 1.74 μM) than the smaller “less-reactive” platelets (Ka = 4.08 μM). However, their maximal rate of aggregation (Vmax, % of platelets aggregating per sec) of 23.3 was significantly lower than the “less-reactive” platelets (Vmax = 34.7). The “reactive” platelets had a 2.2 fold higher level of cyclic AMP.Platelet glycoproteins were labeled using the neuraminidase-galactose oxidase – [H3]-NaBH4 technique. When platelets were labeled after reversible aggregation, the “reactive” platelets showed a two-fold decrease in labeling efficiency (versus control platelets). However, examination of whole cells or membrane preparations from reversibly aggregated platelets revealed no significant difference in Coomassie or PAS (Schiff) staining.These results suggest that the large, “reactive” platelets are more sensitive to ADP but are not hyperaggregable in a kinetic sense. Reversible aggregation may cause a re-orientation of membrane glycoproteins that is apparently not characterized by a major loss of glycoprotein material.


1988 ◽  
Vol 8 (5) ◽  
pp. 1957-1969 ◽  
Author(s):  
R A Shapiro ◽  
D Herrick ◽  
R E Manrow ◽  
D Blinder ◽  
A Jacobson

As an approach to understanding the structures and mechanisms which determine mRNA decay rates, we have cloned and begun to characterize cDNAs which encode mRNAs representative of the stability extremes in the poly(A)+ RNA population of Dictyostelium discoideum amoebae. The cDNA clones were identified in a screening procedure which was based on the occurrence of poly(A) shortening during mRNA aging. mRNA half-lives were determined by hybridization of poly(A)+ RNA, isolated from cells labeled in a 32PO4 pulse-chase, to dots of excess cloned DNA. Individual mRNAs decayed with unique first-order decay rates ranging from 0.9 to 9.6 h, indicating that the complex decay kinetics of total poly(A)+ RNA in D. discoideum amoebae reflect the sum of the decay rates of individual mRNAs. Using specific probes derived from these cDNA clones, we have compared the sizes, extents of ribosome loading, and poly(A) tail lengths of stable, moderately stable, and unstable mRNAs. We found (i) no correlation between mRNA size and decay rate; (ii) no significant difference in the number of ribosomes per unit length of stable versus unstable mRNAs, and (iii) a general inverse relationship between mRNA decay rates and poly(A) tail lengths. Collectively, these observations indicate that mRNA decay in D. discoideum amoebae cannot be explained in terms of random nucleolytic events. The possibility that specific 3'-structural determinants can confer mRNA instability is suggested by a comparison of the labeling and turnover kinetics of different actin mRNAs. A correlation was observed between the steady-state percentage of a given mRNA found in polysomes and its degree of instability; i.e., unstable mRNAs were more efficiently recruited into polysomes than stable mRNAs. Since stable mRNAs are, on average, "older" than unstable mRNAs, this correlation may reflect a translational role for mRNA modifications that change in a time-dependent manner. Our previous studies have demonstrated both a time-dependent shortening and a possible translational role for the 3' poly(A) tracts of mRNA. We suggest, therefore, that the observed differences in the translational efficiency of stable and unstable mRNAs may, in part, be attributable to differences in steady-state poly(A) tail lengths.


1939 ◽  
Vol 23 (1) ◽  
pp. 21-39 ◽  
Author(s):  
Aurin M. Chase ◽  
Emil L. Smith

1. Measurements of visual purple regeneration in solution have been made by a procedure which minimized distortion of the results by other color changes so that density changes caused by the regenerating substance alone are obtained. 2. Bleaching a visual purple solution with blue and violet light causes a greater subsequent regeneration than does an equivalent bleaching with light which lacks blue and violet. This is due to a photosensitive substance which has a gradually increasing effective absorption toward the shorter wavelengths. It is uncertain whether this substance is a product of visual purple bleaching or is present in the solution before illumination. 3. The regeneration of visual purple measured at 560 mµ is maximal at about pH 6.7 and decreases markedly at more acid and more alkaline pH's. 4. The absorption spectrum of the regenerating material shows only a concentration change during the course of regeneration, but has a higher absorption at the shorter wavelengths than has visual purple before illumination. 5. Visual purple extractions made at various temperatures show no significant difference in per cent of regeneration. 6. The kinetics of regeneration is usually that of a first order process. Successive regenerations in the same solution have the same velocity constant but form smaller total amounts of regenerated substance. 7. In vivo, the frog retina shows no additional oxygen consumption while visual purple is regenerating.


Polymers ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 1181 ◽  
Author(s):  
Chunmei Zhang ◽  
Qiaofeng Lan ◽  
Tianliang Zhai ◽  
Shengqiang Nie ◽  
Jun Luo ◽  
...  

Lactide-Caprolactone copolymer (LACL) was added to a Polylactide/Poly(ε-caprolactone) (PLA/PCL) blend as a compatibilizer through solution mixing and the casting method. The melt crystallization behavior and crystalline morphology of PLA, PLA/PCL, and PLA/PCL/LACL were investigated using differential scanning calorimeter (DSC) and polarized optical microscopy (POM), respectively. The temperature of the shortest crystallization time for the samples was observed at 105 °C. The overall isothermal melt crystallization kinetics of the three samples were further studied using the Avrami theory. Neat PLA showed a higher half-time of crystallization than that of the PLA/PCL and PLA/PCL/LACL blends, whereas the half-time of crystallization of PLA/PCL and PLA/PCL/LACL showed no significant difference. The addition of PCL decreased the spherulite size of crystallized PLA, and the nuclei density in the PLA/PCL/LACL blend was much higher than that of the PLA and PLA/PCL samples, indicating that LACL had a compatibilization effect on the immiscible PLA/PCL blend, thereby promoting the nucleation of PLA. The spherulites in the PLA/PCL and PLA/PCL/LACL blend exhibited a smeared and rough morphology, which can be attributed to the fact that PCL molecules migrated to the PLA spherulitic surface during the crystallization of PLA.


2010 ◽  
Vol 67 (11) ◽  
pp. 893-897 ◽  
Author(s):  
Zeljko Lausevic ◽  
Goran Vukovic ◽  
Biljana Stojimirovic ◽  
Jasna Trbojevic-Stankovic ◽  
Vladimir Resanovic ◽  
...  

Background/Aim. Injury-induced anergy is one of the key factors contributing to trauma victims' high susceptibility to sepsis. This group of patients is mostly of young age and it is therefore essential to be able to predict as accurately as possible the development of septic complications, so appropriate treatment could be provided. The aim of this study was to assess kinetics of interleukin (IL) -6 and -10, phospholipase A2- II and C-reactive protein (CRP) in severely traumatized patients and explore the possibilities for early detection of potentially septic patients. Methods. This prospective study included 65 traumatized patients with injury severity score (ISS) > 18, requiring treatment at surgical intensive care units, divided into two groups: 24 patients without sepsis and 41 patients with sepsis. C-reactive protein, IL-6 and -10 and phospholipase A2 group II, were determined within the first 24 hours, and on the second, third and seventh day of hospitalization. Results. Mean values of IL-6 and phospholipase A2-II in the patients with and without sepsis did not show a statistically significant difference on any assessed time points. In the septic patients with ISS 29-35 and > 35 on the days two and seven a statistically significantly lower level of IL-10 was found, compared with those without sepsis and with the same ISS. C-reactive protein levels were significantly higher in septic patients with ISS 18-28 on the first day. On the second, third and seventh day CRP levels were significantly lower in the groups of septic patients with ISS 29-35 and > 35, than in those with the same ISS but without sepsis. Conclusion. Mean levels of CRP on the first day after the injury may be useful predictor of sepsis development in traumatized patients with ISS score 18-28. Mean levels of CRP on the days two, three and seven after the injury may be a useful predictor of sepsis development in traumatized patients with ISS score more than 28. Mean levels of IL-10 on the second and seventh day after the injury may be a useful predictor of sepsis development in traumatized patients with ISS score > 28.


2012 ◽  
pp. 135-139
Author(s):  
Anita Szabó ◽  
István Gonda ◽  
Inre Vágó

Nowadays the success vegetable and fruit production are unimaginable without regular nutrient management. One of the ways to supply the required nutrients in an environmentally friendly way is the application of composts, which is less widespread so far. Compost doses were applied in biological and integrated apple orchards in cooperation with the Institute of Horticultural Science in the years 2010 and 2011. Different changes were resulted by the compost treatments in the examined parameters in case of both apple varieties (Golden Delicious and Pinova). There is no clear effect of compost on the changes of ash-, total acids, Vitamin C and the sugar content until now, because the improvement of the nutritional indicators takes more time. However significant differences were observed after one year between the apple varieties. Higher ash-, total acids and sugar content were measured in case of the apple variety Pinova, while the measurements showed higher Vitamin C content in case of the variety Golden Delicious.


Author(s):  
Mary Kama ◽  
Kaul Gena ◽  
Tindi Seje Nuru

Magnetic skarn ore (MSO) is one of the major copper bearing ore extracted by the Ok Tedi Copper Mine in Papua New Guinea (PNG). Copper minerals are recovered by flotation while the iron not associated with copper are discarded as tailings. The objective of this investigation was to determine the iron ore reduction kinetics for the Ok Tedi MSO and ascertain if it can be processed to produce sponge iron for a mini steel plant in Papua New Guinea. SEM-EDAX analyses of the Ok Tedi MSO indicated 10.1% C, 30% O, 0.6% Mg, 1.1% Si, 21.1% S, 0.8% Ca and 36.2 % Fe. Most of the iron is in sulfide form. Both naturally occurring and roasted sinters of Ok Tedi MSO samples of different particle sizes were reduced by charcoal carbon at three different temperatures and seven different reduction times. Analyses of the reduced products indicated a metallic iron content of more than 65 wt. % on average. Results showed that there was no significant difference in reduction between fluxed and control materials. Only a slight increase in kinetics with reduced particle size, hence the reaction rate constant (K) did not vary much within the temperatures investigated. Reaction kinetics increases with increasing reduction time at 900°C. Therefore, more iron reduction is observed with particles of 106 µm size. In addition, the results also confirmed that the reduction energy used was higher at 800°C and lower at 1000°C. In conclusion, iron reduction can be improved but close monitoring of temperature and reduction times are essential to determine the reaction kinetics of the Ok Tedi MSO.


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