Influence of variety and storage on the polyphenol composition of apple flesh

The impact of catechin and epicatechin, total phenols and PPO activity on the Mal d 1 content in apple fruit

The most important apple allergen in Central Europe and North America is Mal d 1. Apples are a very important source of secondary plant metabolites like polyphenols in human nutrition. It is known that oxidised phenols can bind proteins. These irreversible bindings can lead to a reduced allergenicity. The most important phenols in apple are epicatechin, catechin and their polymeric structures, which have been identified as substrates of the polyphenoloxidase (PPO). The aim of this study was to analyse the influence of naturally occurring catechin and epicatechin contents in apple on the allergenicity of apple fruits. Fruits of the cultivars 'Elstar', 'Diwa' and 'Boskoop' were harvested and stored for 8 and 12 weeks in a cold-chamber at 2 °C. Mal d 1-, catechin-, epicatechin- and total phenol content as well as the activity of PPO were determined. Correlation analysis showed that naturally occurring catechin as well as epicatechin has no impact on the Mal d 1 content of the tested cultivars: correlation coefficient ranged from -0.203 to 0.501 for the correlation between Mal d 1 and catechin. The results further indicated that the activity of PPO is more important than the content of total phenols to reduce the Mal d 1 level. If there is a high PPO activity, Mal d 1 could be reduced even if the total phenol concentration is low.

Flavonoid basics: chemistry, sources, mechanisms of action, and safety

In our efforts to understand how various dietary factors can influence the risk and progression of chronic disease, much recent research has focused on phytochemicals. Phytochemicals are defined as nonessential nutrients found in plant-based food, many of which have been established as bioactive and thus may affect human health. The largest group of phytochemicals is the polyphenols, comprised principally of the flavonoids, which are characterized chemically by two benzene rings joined by a linear carbon chain. Evidence from observational studies indicates that regular consumption of foods containing flavonoids may reduce the risk several chronic conditions, including neurodegenerative diseases, atherosclerosis, and certain forms of cancer. These results have generated considerable interest in flavonoids, although much basic information about their nutrient characteristics in humans remains limited, e.g., their bioavailability and metabolism, interactions with other dietary factors, mechanisms of action, and intakes associated with specific health outcomes. Although flavonoids are commonly defined as dietary antioxidants and their putative health benefits commonly attributed to this mechanism, it now appears their principal actions are mediated in vivo via other biochemical and molecular pathways.

Changes in Quality and Biochemical Parameters in ‘Idared’ apples during Prolonged Shelf Life and 1-MCP treatment

In this study, changes in quality and various biochemical parameters of ‘Idared’ apples during prolonged shelf life period after ultra-low oxygen (ULO) storage were investigated. Additionally, the impact of the postharvest application of 1-methylcyclopropene (1-MCP) on different parameters was evaluated. After the harvest, apples were stored in the ULO storage for 6 months and then exposed to room temperature. Fruit firmness, peel color, and changes in sugars, organic acids and phenolics were monitored during the 3 weeks of shelf life. Malic acid, sugars and firmness decreased at room temperature. However, the color of the apples remained unchanged. The level of citric and ascorbic acid remained constant. Levels of phenolics in the peel increased significantly, whereas remained constant in the pulp of apples. 1-MCP treatment resulted in higher amounts of fructose and glucose, malic acid and greater firmness of apples. However, 1-MCP did not influence the phenolic content, ascorbic acid or color. The results obtained indicate that the content of different health-promoting compounds of apples does not change dramatically at room temperature. At the same time these results suggest that 1-MCP could be useful for maintaining certain quality and biochemical parameters and might extend the shelf life of apples.

Effect of sample preparation on the measurement of sugars, organic acids, and polyphenols in apple fruit by mid-infrared spectroscopy

The objectives of this study were (i) to test different conditions of freezing, thawing, and grinding during sample preparation and (ii) to evaluate the possibility of using mid-infrared spectroscopy for analyzing the composition of sugars, organic acids, and polyphenols in apples. Seven commercial apple cultivars were chosen for their large variability in composition (total polyphenols from 406 to 1033 mg kg(-1) fresh weight). The different conditions of sample preparation affected only the phenolic compounds and not sugars or organic acids. The regression models of the mid-infrared spectra showed a good ability to estimate sugar and organic acid contents (R(2) ≥ 0.96), except for citric acid. Good predictions were obtained for total phenolic, flavan-3-ols, and procyanidins (R(2) ≥ 0.94) provided oxidation was avoided during sample preparation. A rapid and simple procedure was then proposed for phenolic compounds using sodium fluoride during sample homogenization at ambient temperature and freeze-drying before spectra acquisition.

Polyphenols and human health: a prospectus

The lay press often heralds polyphenols as panacea for all sorts of diseases. The rationale is that their antioxidant activity would prevent free radical damage to macromolecules. However, basic and clinical science is showing that the reality is much more complex than this and that several issues, notably content in foodstuff, bioavailability, or in vivo antioxidant activity are yet to be resolved. We summarize the recent findings concerning the effects of polyphenols on human health, analyze the current limitations at pitfalls, and propose future directions for research.

Phloridzin reduces blood glucose levels and improves lipids metabolism in streptozotocin-induced diabetic rats

Phloridzin is the specific and competitive inhibition of sodium/glucose cotransporters in the intestine (SGLT1) and kidney (SGLT2). This property which could be useful in the management of postprandial hyperglycemia in diabetes and related disorders. Phloridzin is one of the dihydrochalcones typically contained in apples and in apple-derived products. The effect of phloridzin orally doses 5, 10, 20 and 40 mg/kg body weight on diabetes was tested in a streptozotocin-induced rat model of diabetes type 1. From beneficial effect of this compound is significant reduction of blood glucose levels and improve dyslipidemia in diabetic rats. As a well-known consequence of becoming diabetic, urine volume and water intake were significantly increased. Administration of phloridzin reduced urine volume and water intake in a dose-dependent manner. Phloretin decreases of food consumption, as well as a marked lowering in the weight. In conclusion, this compound could be proposed as an antihyperglycemic and antihyperlipidemic agent in diabetes and potential therapeutic in obesity.

Postharvest Fruit Rots of Apple in Greece: Pathogen Incidence and Relationships Between Fruit Quality Parameters, Cultivar Susceptibility, and Patulin Production

The incidence of pathogens associated with postharvest fruit rots on the four most extensively cultivated apple cultivars (Red Delicious, Golden Delicious, Granny Smith, and Fuji) in Greece was surveyed during two consecutive storage periods (2008-09 and 2009-10) in five packinghouses located in northern Greece. The fungi isolated were identified based on their morphological characteristics and internal transcribed spacer gene sequencing. In the four cultivars sampled, Penicillium expansum and Botrytis cinerea were the predominant pathogens, accounting for averages of 44.2 and 23.6%, respectively, of the pathogens isolated from the sampled fruit. Two other important rot pathogens were Alternaria tenuissima and Mucor pyriformis, accounting for 16.1 and 6.6%, respectively, of the diseased apple fruit. Other pathogens such as Monilinia laxa, M. fructigena, Botryosphaeria obtusa, Geotrichum candidum, Fusarium avenaceum, and F. proliferatum were isolated at low frequencies and are considered of minor importance. Measurements of the resistance level of the four apple cultivars to fruit rot caused by P. expansum and Botrytis cinerea revealed that Golden Delicious was the most susceptible to blue mold while Fuji was the most susceptible to gray mold infections. Susceptibility to gray mold was negatively correlated with flavonoid and phenol concentration as well to fruit antioxidant activity, while susceptibility to blue mold was negatively correlated with fruit firmness and phenol concentration. Patulin production was significantly higher in Red Delicious and Golden Delicious fruit than in Granny Smith and Fuji fruit and was negatively correlated with the acidity of the fruit. The high incidence of P. expansum and A. tenuissima along with the presence of F. avenaceum and F. proliferatum, all of which are potentially mycotoxin producers, emphasize the risk for mycotoxin contamination of apple fruit juices and by-products. Furthermore, information on the distribution of the pathogens on the main cultivars may be useful for the implementation of strategies to control the diseases and minimize the threat of mycotoxin contamination on each cultivar.

Chemoprevention of intestinal polyps in ApcMin/+ mice fed with western or balanced diets by drinking annurca apple polyphenol extract

The Western diet (WD) is associated with a higher incidence of colorectal cancer (CRC) than the Mediterranean diet. Polyphenols extracted from Annurca apple showed chemopreventive properties in CRC cells. A multifactorial, four-arm study by using wild-type (wt) and Apc(Min/+) mice was carried out to evaluate the effect on polyp number and growth of APE treatment (60 μmol/L) ad libitum in drinking water combined with a WD or a balanced diet (BD) for 12 weeks. Compared with APE treatment, we found a significant drop in body weight (P < 0.0001), severe rectal bleeding (P = 0.0076), presence of extraintestinal tumors, and poorer activity status (P = 0.0034) in water-drinking Apc(Min/+) mice, more remarkably in the WD arm. In the BD and WD groups, APE reduced polyp number (35% and 42%, respectively, P < 0.001) and growth (60% and 52%, respectively, P < 0.0001) in both colon and small intestine. Increased antioxidant activity was found in wt animals fed both diets and in Apc(Min/+) mice fed WD and drinking APE. Reduced lipid peroxidation was found in Apc(Min/+) mice drinking APE fed both diets and in wt mice fed WD. In normal mucosa, mice drinking water had lower global levels of DNA methylation than mice drinking APE. APE treatment is highly effective in reducing polyps in Apc(Min/+) mice and supports the concept that a mixture of phytochemicals, as they are naturally present in foods, represent a plausible chemopreventive agent for CRC, particularly in populations at high risk for colorectal neoplasia.

The effect of postharvest 1-MCP treatment and storage atmosphere on 'Cripps Pink' apple phenolics and antioxidant activity

This study investigated the effect of a postharvest 1-methylcyclopropene (1-MCP) treatment, controlled atmosphere and storage time on the total antioxidant activity (TAA) and phenolic compounds in the peel and flesh of 'Cripps Pink' apples (Malus domestica Borkh.). Preclimacteric apples were harvested and treated with 1-MCP then stored in normal atmosphere (NA) or controlled atmosphere (CA) at 0°C for up to 160days. In general, the level of phenolics decreased by 9% in the peel and significantly increased twofold in the flesh during cold storage, regardless of storage atmosphere or 1-MCP treatment. However, treatment with 1-MCP resulted in significantly lower concentrations of chlorogenic acid and procyanidin B2 in apple flesh, and catechin and epicatechin in the peel compared to the control fruits. There was no significant effect of CA on the phenolic compounds during long-term storage, except for quercetin 3-galactoside and quercetin 3-glucoside, which both significantly increased under CA storage. Total antioxidant activity (TAA) is an important nutritional attribute of apples in the human diet. The results showed that TAA in the peel tissue was about eight times higher than that of the flesh, with mean values of 4.75gTE/kgFW and 0.56TE/kgFW, respectively. The TAA in both the peel and flesh tissue increased significantly during storage by 40% and 70%, respectively. The storage atmosphere did not significantly affect TAA in either the peel or flesh, whilst the 1-MCP treatment significantly reduced the TAA in the peel tissue only. These results show the beneficial combined effects of pre-storage 1-MCP treatment and CA on 'Cripps Pink' apple phenolic composition and antioxidant capacity during long term storage.

Impact of shelf life on content of primary and secondary metabolites in apple (Malus domestica Borkh.)

In this study, we evaluated the changes in apple fruit quality during shelf life. After a month of cold storage, apples of cultivars "Jonagold" and "Golden Delicious" were exposed to ambient temperatures for 21 d, with subsequent sampling every 3 or 4 d. Fruit firmness, changes in amounts of sugars, malic acid, and phenolics were observed during shelf life. Chemical analyses were done with HPLC-PDA system. An interchange between various sugars was noticed, but in general, the sum of sugars remained at the same level. The content of malic acid remained stable or dropped, resulting in sweeter fruit. Levels of phenolics were more constant in the pulp of both cultivars analyzed, while in the peel, the changes were more pronounced. In the pulp, a peak in the content of hydroxycinnamic acids and flavanols was noticed on the 2nd or 3rd sampling and afterwards, the amounts remained constant. In the peel an initial decrease of all analyzed phenolic groups was observed in both cultivars, however it was more pronounced in "Jonagold." It can be concluded that changes in primary and secondary metabolites are not the main reason for the lower quality of fruit exposed to ambient temperatures. On the other hand, fruit firmness might be the limiting factor for shelf life duration.

Chlorogenic acid differentially alters hepatic and small intestinal thiol redox status without protecting against azoxymethane-induced colon carcinogenesis in mice

Colorectal cancer (CRC) is a leading cause of cancer-related deaths in the United States. Epidemiological data have suggested that coffee consumption is inversely related to CRC risk, which may be attributed to chlorogenic acid (CGA), an ester of caffeic acid (CA) and quinic acid. This study was conducted to determine whether chronic dietary CGA supplementation would attenuate tumorigenesis and oxidative stress in a mouse model of azoxymethane (AOM)-induced colon cancer. Mice (4-wk old; n = 15/group) were fed CGA (0%, 0.01%, or 0.1%) for 20 wk and received 6 weekly intraperitoneal AOM injections (10 mg/kg). CGA and CA dose-dependently accumulated in the small intestinal mucosa. AOM induced (P < 0.05) colonic aberrant crypt foci (14.2 +/- 1.9/field) and tumors (14.6 +/- 1.1/colon), which were correlated (r = .677; P < 0.05), and CGA at either dose did not reduce tumorigenesis. Hepatic GSH/GSSG and Cys/CySS ratios were unaffected by AOM, but CGA at 0.1% increased these ratios by decreasing GSSG and CySS. CGA did not affect the ratios of small intestinal GSH/GSSG or Cys/CySS, which were decreased in response to AOM treatment. Collectively, these data indicated that CGA did not protect against AOM-induced tumorigenesis but affected hepatic thiol redox status in this colon cancer model.

Bioavailability of the polyphenols: status and controversies

The current interest in polyphenols has been driven primarily by epidemiological studies. However, to establish conclusive evidence for the effectiveness of dietary polyphenols in disease prevention, it is useful to better define the bioavailability of the polyphenols, so that their biological activity can be evaluated. The bioavailability appears to differ greatly among the various phenolic compounds, and the most abundant ones in our diet are not necessarily those that have the best bioavailability profile. In the present review, we focus on the factors influencing the bioavailability of the polyphenols. Moreover, a critical overview on the difficulties and the controversies of the studies on the bioavailability is discussed.

Influence of postharvest processing and storage on the content of phenolic acids and flavonoids in foods

The review is based on the evaluation of electronically collated data published between 2002 to June 2006. It is based on 325 references dealing with the following subclasses of phenolic compounds: hydroxycinnamic and hydroxybenzoic acids, chalcones, flavanones, flavones, flavonols, monomeric flavanols and anthocyanins. Only publications dealing directly with the effects of storage and postharvest processing on the phenolic acid and flavonoid contents of foods were considered. The expectation that the structural diversity even within each subgroup, and the number of different procedures and of different parameters would make finding homogenous tendencies unlikely, has, in most instances, been confirmed. By adding a database Excel table combined with a focused and unified evaluation, specific additional information was rendered accessible and concise. It holds true for most of the subclasses in question that the effect of storage and food processing on the polyphenol content is negligible in comparison to the differences between different varieties of plants. Variety dependence must always be considered, for all classes of compounds.

High contents of nonextractable polyphenols in fruits suggest that polyphenol contents of plant foods have been underestimated

The content of polyphenols in fruits reported in the literature normally refers to extractable polyphenols (EPP) analyzed in aqueous-organic extracts. However, significant amounts of bioactive compounds that are usually not considered in nutritional studies remain in the residue from extraction as nonextractable polyphenols (NEPP). The main objective of this work was to analyze both EPP and NEPP (hydrolyzable polyphenols and proanthocyanidins). EPP were analyzed in methanol/acetone/water extracts, and NEPP were determined in acidic hydrolysates of extraction residue from apple, peach, and nectarine using HPLC-MS and spectrophotometry. Results showed that the NEPP content (112-126 mg/100 g of fresh fruit) was higher than the EPP content (18.8-28 mg/100 g of fresh fruit). Further analyses of NEPP in other fruits and plant foods consumed in diets are needed to compile a complete database of use for nutritional and biological studies.

Dietary phloridzin reduces blood glucose levels and reverses Sglt1 expression in the small intestine in streptozotocin-induced diabetic mice

Phloridzin is a dihydrochalcone typically contained in apples. In this study, it is shown that a diet containing 0.5% phloridzin significantly reduced the blood glucose levels in streptozotocin (STZ)-induced diabetic mice after 14 days. We detected phloridzin in the plasma of STZ-induced diabetic mice fed the phloridzin diet for 14 days, although its concentration was much lower than that of the phloridzin metabolites. A quantitative RT-PCR analysis showed a reversal of STZ induction of the sodium/glucose cotransporter gene Sglt1 and the drug-metabolizing enzyme genes Cyp2b10 and Ephx1 in the small intestine of mice fed a 0.5% phloridzin diet. These mice also showed a reversal of the STZ-mediated renal induction of the glucose-regulated facilitated glucose transporter gene Glut2. Dietary phloridzin improved the abnormal elevations in blood glucose levels and the overexpression of Sglt1, Cyp2b10, and Ephx1 in the small intestine of STZ-induced diabetic mice.

Bioactivity and structure of biophenols as mediators of chronic diseases

Biophenols and their associated activity have generated intense interest. Current topics of debate are their bioavailability and bioactivity. It is generally assumed that their plasma concentrations are insufficient to produce the health benefits previously attributed to their consumption. However, data on localized in vivo concentrations are not available and many questions remain unanswered. Potential mechanisms by which they may exert significant bioactivity are discussed together with structure activity relationships. Biophenols are highly reactive species and they can react with a range of other compounds. Products of their reaction when functioning as antioxidants are examined.

Polyphenol levels and free radical scavenging activities of four apple cultivars from integrated and organic farming in different italian areas

This paper investigates the influence of cultivar (Annurca, Golden Delicious, Red Chief, and Stayman Neepling), rural practice (integrated and organic), and growing region (different Italian regions) on polyphenol composition and antiradical activity of the pulp and skin of apples, as presented to the consumer at the market. Antiradical activity of fruit was strongly related with the total polyphenolic content, determined both by the spectrophotometric Folin-Ciocalteu method ( R (2) = 0.90; P < 0.01) and by HPLC ( R (2) = 0.85; P < 0.01). Considering the edible portion of the fruit, polyphenolics contribute toward explaining approximately 90% of the overall antiradical activity, thus highlighting their important role in human health protection. Therefore, the data indirectly indicated that ascorbic acid and other antiradical molecules differing from polyphenols play a much less important role in explaining the health-protecting properties of apples. Cultivar effect was by far the most important, and Annurca and Golden Delicious were respectively the best and the worst apples from the point of view of the health-protecting attributes.

Polyphenolic compounds and antioxidant activity of new and old apple varieties

There is considerable evidence to show that a greater intake of apple contributes to improved health by reducing the risk of diseases, such as cardiovascular disease and some forms of cancer. Apple fruit is a major source of phenol compounds, because its consumption is widespread in many countries and it is available on the market for the whole year. The phenolic composition of 67 varieties of apple cultivars (new and old varieties) was examined for the concentration of some important phytochemicals and antioxidant activity. For the first time, we have looked at the correlation and compared polyphenolic coumpounds in Golden Delicious variety and new varieties grown from it. Up to 18 compounds, including catechin, procyanidin, hydroxycinnamates, flavonols, anthocyanins, and dihydrochalcones, were analyzed by high-performance liquid chromatography with diode array detection analysis of crude extracts and after thiolysis and LC-MS. The mean content of total polyphenols lay between 523.02 and 2723.96 mg/100 g dw and depending upon the apples variety. Flavanols (catechin and oligomeric procyanidins) are the major class of apple polyphenols, representing more than 80%, followed by hydroxycinnamic acids (1-31%), flavonols (2-10%), dihydrochalcones (0.5-5%), and in red apples, anthocyanins (1%). In this study, the best correlation was found for the total polyphenols and ABTS method, with a lower correlation for FRAP and DPPH methods ( r = 0.871, 0.839, and 0.804, respectively). The presented data clearly demonstrated that new varieties, i.e., Ozark Gold, Julyred, and Jester, of apple had the same or higher value of bioactive compounds in comparison to the old varieties, i.e., Golden Delicious, Idared, and Jonagold.

Annurca apple polyphenols have potent demethylating activity and can reactivate silenced tumor suppressor genes in colorectal cancer cells

The CpG island methylator phenotype is characterized by DNA hypermethylation in the promoters of tumor suppressor genes with silencing of transcription. Hypermethylation of the promoter of hMLH1 and subsequent microsatellite instability occurs in approximately 12% of sporadic colorectal cancers (CRC). Annurca apple, a variety of southern Italy, is rich in polyphenols that are associated with anticancer properties. Populations in southern Italy have lower incidences of CRC than elsewhere in the western world. We evaluated the mechanisms of putative anticancer effects of Annurca polyphenol extract (APE) in in vitro models of CRC. We extracted polyphenols from Annurca apples and treated RKO, SW48, and SW480 cells with APE and assessed the cell viability, apoptosis, and cell cycle. DNA methylation of selected tumor suppressor genes was evaluated after treatment with APE and was compared with the synthetic demethylating agent 5-aza-2'deoxycytidine (5-aza-2dC). DNA methyltransferase (DNMT)-1 and -3b levels were evaluated. Decreased cell viability and induction of apoptosis was evident after treatment. We found no significant changes in cell cycle dynamics. We observed significant increases of p53 protein expression in RKO after treatment. APE treatment strongly reduced DNA methylation in the promoters of hMLH1, p14(ARF), and p16(INK4a) with consequent restoration of normal expression. These effects were qualitatively comparable with those obtained with 5-aza-2dC. We observed a significant reduction in expression of DNMT proteins after treatment without changes in messenger RNA. In conclusion, APE have potent demethylating activity through the inhibition of DNMT proteins. The lack of toxicity in Annurca extracts makes them excellent candidates for the chemoprevention of CRC.

Effect of reddening-ripening on the antioxidant activity of polyphenol extracts from cv. 'Annurca' apple fruits

Apple is among the most consumed fruits worldwide, and several studies suggest that apple polyphenols could play a role in the prevention of degenerative diseases. 'Annurca' apple fruit undergoes, after harvest, a typical reddening treatment to turn the apples' skin red, and it is noted for its high firmness. This paper reports the effect of reddening-ripening treatment on polyphenol concentration and antioxidant activity of both peel and flesh extracts. The in vitro antioxidant properties have been compared with the protective effect against the cytotoxic effects of reactive oxygen species using Caco-2 cells as model system. Pretreatment of cells with different polyphenolic apple extracts provides a remarkable protection against oxidative damage. This effect seems to be associated with the antioxidant activity of 'Annurca' apple polyphenolic compounds. The flesh has antioxidant properties comparable to those possessed by the peel. Neither the reddening nor the fruit conservation causes changes in the antioxidant properties possessed by this apple variety. The data indicate that polyphenolic compounds in 'Annurca' apples are relatively stable in the peel and also in the flesh; therefore, the health benefits of polyphenols should be maintained during long-term storage. Finally, a diet rich in apple antioxidants could exert a beneficial effect in the prevention of intestinal pathologies related to the production of reactive oxygen species.

Proteomic analysis of the major soluble components in Annurca apple flesh

Apple is one of the most worldwide-consumed fruits and a number of cultivars, differing in organoleptic and nutritional characteristics, are available for the market. Annurca apple is a regional variety from Southern Italy, which is known for crispness, excellent taste and long shelf life of fruits. These features have renewed the interest in the investigation of their genetic potential and different studies have lead to their partial genetic and metabolic characterisation. In this study, we present the analysis of the protein repertoire of the pseudocarp tissues of three accessions of Malus x domestica Borkh. cv. Annurca, as first example of the systematic annotation of the apple proteome. Proteins were extracted from fruit tissues and resolved on 2-DE gels; commonly expressed proteins were in-gel digested and analysed by MALDI-TOF-MS and muLC-ESI-IT-MS/MS approaches. Peptide MS and MS/MS data were searched against publicly available protein and EST databases, and 44 spots were identified and associated to 28 different species. They were related to important physiological processes such as energy production, ripening and stress response. The occurrence of allergens causative of widespread food allergy syndromes was also detected. Integration of genomic, metabolomic and proteomic data will be indispensable for future molecular characterisation and hence full exploitation of the peculiar organoleptic, nutritional and agronomic traits of local cultivars of fruits.

Concentrations and characteristics of procyanidins and other phenolics in apples during fruit growth

Apples (Malus domestica Borkh.) of two table and two cider cultivars were collected during fruit growth and maturation from the end of cell proliferation. Concentrations of flavonoids (flavan-3-ols, dihydrochalcones and flavonols) in the fruit flesh decreased sharply between circa 35 and circa 100 days after flowering. For hydroxycinnamic acids, the decrease appeared slower. In a second experiments apples of the cider cultivars Kermerrien and Avrolles were sampled every 2 weeks from 40 days after flowering to overripeness for a detailed characterisation of polyphenol accumulation kinetics in the fruit flesh. Most polyphenol synthesis had occurred at 40 days after full bloom, though it persisted at a low (Kermerrien) to very low (Avrolles) level during all the fruit growth. All qualitative characteristics of the polyphenols were remarkably stable. The degree of polymerisation of the procyanidins increased slightly in Avrolles and decreased in Kermerrien. This was accompanied by a relative increase in procyanidin B2, while size-exclusion chromatography of Kermerrien polyphenol extracts showed the disappearance of a highly polymerised fraction.

Use of molecular markers and flow cytometry to preserve ancient Annurca apple germplasm

The old Annurca apple cultivar (Malus domestica), particularly appreciated for its peculiar flavor and crispy flesh, was studied in order to preserve its ancient germplasm. Twelve clones of Annurca were analyzed using random amplified polymorphic DNA (RAPD) and simple-sequence repeat (SSR) markers. Two out of 30 RAPD primers and nine out of ten SSR primers were able to discriminate all the clones analyzed. Data were confirmed by measuring DNA content using flow cytometry. The results provide a good procedure to improve germplasm field management, in order to removing redundant material in the Annurca collection. This represents an efficient way to create a data bank in order to preserve the genetic variability of the Annurca cultivar.

Annurca apple-rich diet restores long-term potentiation and induces behavioral modifications in aged rats

The impairment of brain functions during aging could be prevented by an increase in antioxidative defenses. In fact, dietary manipulation with antioxidants or with antioxidant-rich extracts from vegetables and fruit can ameliorate age-associated behavioral alterations. Moreover, dietary supplements of antioxidants can reverse the age-dependent impairment to sustain long-term potentiation (LTP). There is evidence that fresh fruit could be more effective than antioxidant supplements or fruit and vegetable extracts but the effect of a diet enriched in fresh fruit on brain aging process has not been investigated until now. The aim of the present study was to verify whether dietary manipulation with fresh apples could influence age-induced changes in motor and emotional behavior and in LTP in rats. Groups of aged and young rats were fed with a standard diet or a diet supplemented with fresh apples of annurca variety for 10 weeks and assessed for behavioral performance in the open field and elevated plus maze tests and for the ability to sustain LTP. The brains were then removed, histochemically stained for superoxide dismutase (SOD) and SOD activity was measured by computer-assisted image analysis. The aged rats fed with the enriched diet showed a significant decrease in the anxiety level. Moreover, they improved in the ability to sustain LTP, reaching the level of the young rats. SOD activity was increased in the aged rats fed with the standard diet whereas SOD activity in the hippocampus of the aged rats treated with annurca apple was at the level of the young animals. These results suggest that a diet rich in annurca apple could have an important role in health-care during aging.

Antioxidant and antiulcerative properties of phenolics from Chinese quince, quince, and apple fruits

To evaluate the health benefits of Chinese quince and quince phenolics, their antioxidant properties and antiulcerative activity were investigated in comparison with apple phenolics as a reference. The strength of antioxidant activity and DPPH radical scavenging activity of these fruit phenolics varied according to different in vitro evaluation systems, whereas the antioxidative property of rat blood increased in all rats orally administered phenolics. Ferulic acid and isoferulic acid were detected as major metabolites in rats given apple phenolics, quince phenolics, and 5-caffeoylquinic acid standard. (-)-Epicatechin and its 3'-O-methyl ether could be detected in rats administered apple phenolics and (-)-epicatechin standard. In the ethanol-induced gastric ulcer, pre-administration of Chinese quince and quince phenolics suppressed the occurrence of gastric lesions in rats, whereas apple phenolics seemed to promote ulceration. The trend of myeloperoxidase activity was similar to that of the ulcer index. The results showed that Chinese quince and quince phenolics might have health benefits by acting both in blood vessels and on the gastrointestinal tract.

Apples increase nitric oxide production by human saliva at the acidic pH of the stomach: a new biological function for polyphenols with a catechol group?

Dietary inorganic nitrate is secreted in saliva and reduced to nitrite by bacterial flora. At the acidic pH of the stomach nitrite is present as nitrous acid in equilibrium with nitric oxide (*NO), and other nitrogen oxides with nitrating and nitrosating activity. *NO in the stomach exerts several beneficial effects, but nitrosating/nitrating species have been implicated as a possible cause of epithelial neoplasia at the gastroesophageal junction. We investigated the effects of apple extracts on *NO release by human saliva at pH 2. A water extract obtained from apple homogenate increased *NO release caused by acidification of saliva. Data show that polyphenols were responsible for this activity, with chlorogenic acid and (+)-catechin the most active and concentrated species. However, ferulic acid, a hydroxycinnamic acid with only one aromatic hydroxyl group, did not increase *NO release. Fructose, the most representative sugar in apples, was also inactive. Interestingly, ascorbic acid in saliva induced a SCN(-)-enhanced burst of *NO but, unlike apple, the release was transient. The simultaneous addition of ascorbic acid and apple extract caused a burst of *NO followed by the increased steady-state level characteristic of saliva containing apple extract. Chlorogenic acid and (+)-catechin, but not ferulic acid, formed o-semiquinone radicals and nitrated polyphenols, suggesting the scavenging of *NO(2) by o-semiquinones. Our results propose that some apple polyphenols not only inhibit nitrosation/nitration but also promote *NO bio-availabilty at the gastric level, a previously unappreciated function.

Antioxidant activity, cytotoxicity, and DNA information of Glossogyne tenuifolia

This study investigates the antioxidant activity and cytotoxicity of Glossogyne tenuifolia extract on various cancer cell lines. The 5.8s DNA of G. tenuifolia was isolated, and the species of this plant was confirmed by NCBI's DNA database. G. tenuifolia was then extracted with ethanol and separated into several fractions using the partition procedure with water, n-butanol, and ethyl acetate (EA). Among these, the EA fraction most significantly affected the activity of DPPH(*) and superoxide anion scavenging. Additionally, only the EA fraction exhibited cytotoxicity on breast cancer cells (MCF-7 and MDA-MB-231) and liver cancer cells (Hep G2 and Hep 3B). Next, the EA fraction was further separated by column chromatography, and 15 fractions were obtained. Three effective components were isolated and identified separately from the active fractions: oleanolic acid (OA) from fraction 6, luteolin from fractions 8-10, and luteolin-7-glucoside from fraction 12. The test of these three compounds on scavenging activity of DPPH(*) and superoxide anion indicates that luteolin had the highest antioxidant activity, whereas the effect of OA was negligible. Additionally, a synergistic effect between luteolin and luteolin-7-glucoside was observed. Kick-out experiments showed that the activities were vanished or decreased. Especially on MDA-MB-231 and MCF-7 cells, the cytotoxicity completely disappeared when luteolin was eliminated from fractions 8-10. These findings demonstrate that luteolin plays a crucial role in the inhibition of the growth of hepatoma cancer cell lines. Fraction 3, which did not contain luteolin, luteolin-7-glucoside, and oleanolic acid, had cytotoxicity on MDA-MB-231, MCF-7, Hep G2, Hep 3B, and A549, which implies that this fraction contained some other effective ingredients and requires further study. The investigation is currently underway in our laboratory.

Radical-Scavenging Activities of New Hydroxylated Ursane Triterpenes from cv. Annurca Apples

Two new ursolic acid triterpene derivatives, compounds 2 and 3, have been isolated from cv. Annurca apple fruit, a high-quality apple variety widely cultivated in southern Italy, together with the known 2-oxopomolic acid (1). The new compounds were identified by means of different spectroscopic techniques as 3-epi-2-oxopomolic acid (= (3alpha)-3,19-dihydroxy-2-oxours-12-en-28-oic acid; 2) and (1alpha)-1-hydroxy-3-oxours-12-en-28-oic acid (3). Compounds 1-3 were tested for their radical-scavenging activities with the aid of a 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay (Fig. 2). All three constituents showed activities similar to that of the reference antioxidant alpha-tocopherol (vitamin E).