Ellagitannin Content Research Articles

Potential of ultrafiltration for separation and purification of ellagitannins in blackberry (Rubus adenotrichus Schltdl.) juice

Tropical highland blackberry is characterized by its high content of ellagitannins, which are considered to be potentially beneficial for human health, but relatively rare in food sources. Due to its relatively high molecular weight, the feasibility of selective separation of ellagitannins by ultrafiltration was assessed on clarified tropical highland blackberry juice. Six organic tight ultrafiltration membranes with nominal molecular weight cut-off (MWCO) ranging from 1 to 150kDa were tested. Filtration temperature was set constant to 30°C, cross-flow velocity to 0.3ms−1 and transmembrane pressures varied at 0.5, 1, 1.5, 2 and 3MPa, for each membrane tested. Experiments were performed at a constant volumetric reduction ratio (1<VRR<1.1) and quantitative analyses of total ellagitannins and anthocyanins were determined by HPLC/DAD. Retention of ellagitannins reached 100% for all membranes except for that showing a nominal MWCO of 150kDa, when transmembrane pressure was over 1MPa. Retention of total anthocyanins increased with transmembrane pressure and reached values over 90% for all membranes tested at 3MPa. A membrane with a nominal MWCO of 2kDa presented the highest anthocyanin flux at 2MPa and thus appeared to be the most promising for fractionation of the polyphenolic compounds. A model used to predict total ellagitannin purification with constant volume diafiltration confirmed that this membrane presented one of the lowest diavolumes needed to achieve a purity of 90% at higher transmembrane pressures.

Study of phenolic potential of seasoned and toasted Portuguese wood species (&lt;em&gt;Quercus pyrenaica&lt;/em&gt; and &lt;em&gt;Castanea sativa&lt;/em&gt;)

&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Aim&lt;/strong&gt;: The phenolic potential and suitability of seasoned and toasted Portuguese chestnut (&lt;em&gt;Castanea sativa&lt;/em&gt; Mill) and oak wood (&lt;em&gt;Quercus pyrenaica&lt;/em&gt;) as alternative cooperage materials were evaluated.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Methods and results&lt;/strong&gt;: Low-molecular-weight phenols and ellagitannins from seasoned and toasted Portuguese wood species were analysed by HPLC. &lt;em&gt;C. sativa&lt;/em&gt; was found to be richer in phenolic compounds than &lt;em&gt;Q. pyrenaica&lt;/em&gt;. High concentrations of vescalagin and gallic acid were specific to &lt;em&gt;C. sativa&lt;/em&gt;. Toasting significantly reduced the ellagitannin content in both wood types, albeit less markedly in &lt;em&gt;C.&lt;/em&gt; &lt;em&gt;sativa&lt;/em&gt;. As regards phenolic aldehydes, &lt;em&gt;C. sativa&lt;/em&gt; contained substantially greater amounts of vanillic aldehyde, an odour-active compound, than &lt;em&gt;Q. pyrenaica&lt;/em&gt;.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Conclusion&lt;/strong&gt;: Both types of Portuguese wood are suitable for use as cooperage materials, although chestnut wood is better suited to the heat treatment involved in the coopering process.&lt;/p&gt;&lt;p style="text-align: justify;"&gt;&lt;strong&gt;Significance and impact of the study&lt;/strong&gt;: Portuguese wood species provide an effective alternative to the oak wood species traditionally used for aging alcoholic beverages.&lt;/p&gt;

Phytochemical composition, antioxidant and antimicrobial properties of raspberry fruit, pulp, and marc extracts

In this study, the phytochemical composition (total phenolics, total anthocyanins and ellagitannins) and antimicrobial properties of raspberry fruit, pulp, and marc extracts obtained with 80% methanol and 80% acetone from different plant cultivars were assessed. The extracts were also subjected to screening for their possible antioxidant activity by using 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) assay. The content of total phenolics in berry pulp extracts varied from 20.4 to 35.5, in whole berry extracts from 43.6 to 83.1 and in berry marc extracts from 93.9 to 163.8 mg/g (dry weight of extract). The content of ellagitannins was higher by 63–80% in raspberry marc extracts than in pulp extracts. Raspberry fruit, pulp and marc extracts isolated with aqueous acetone possessed stronger antimicrobial activity than the corresponding extracts isolated with aqueous methanol. The highest inhibitory effect against the investigated Gram-positive bacteria and yeast strains was shown by the extracts isolated from raspberry marc and containing the highest concentrations of total phenolics and ellagitannins.

Evolution of Ellagitannin Content and Profile during Fruit Ripening in Fragaria spp.

Ellagitannins and ellagic acid conjugates are polyphenols present in the human diet, in particular strawberries (Fragaria spp.). The first aim of this study was isolation and structural characterization of casuarictin and 3-O-methyl ellagic acid 3'-O-α-rhamnopyranoside, which were found to be abundant in Fragaria spp., along with agrimoniin. The second aim was accurate profiling and quantification of 26 ellagitannins and ellagic acid conjugates in six Fragaria x ananassa cultivars and two Fragaria vesca species. The third aim was to describe the ellagitannins behavior during fruit ripening from the green stage to over-ripeness. It was shown that there are major qualitative and quantitative differences in the amount and profile of ellagitannins and ellagic acid conjugates between Fragaria spp. Genotype is a major factor in defining ellagitannin concentration and patterns between strawberries, and variable behavior of the genotypes was observed, in the context of a significant drop in ellagitannins during ripening.

Comparative study of chemical and phenolic compositions of two species of jaboticaba: Myrciaria jaboticaba (Vell.) Berg and Myrciaria cauliflora (Mart.) O. Berg

The chemical composition and in vitro antioxidant capacity (AC) of the two most commercialized species of jaboticaba, Sabará (Myrciaria jaboticaba) and Paulista (Myrciaria cauliflora), were compared in different fruit parts (skin, pulp and seeds) and at different ripening stages. Both species presented similar mineral and centesimal compositions, and were found to be rich sources of Mn (1.8–2.7mg/100gDW) and Cu (1.0mg/100gDW). Except for anthocyanins, phenolic concentrations were in greater amounts in Sabará than in Paulista. Ellagic acid derivatives (EA) contents varied according to ripening stage and also across fruit parts (skin, pulp and seeds). Unripe jaboticaba showed the highest contents of proanthocyanidins (PAC) and ellagitannins, as well as the greatest antioxidant capacity. Complete ripening led to a decrease of 47% in total EA, 43% in PAC, 60–77% in AC. Seeds displayed the highest concentrations of ellagitannins and proanthocyanidins and the greatest AC, whereas skin exhibited the highest amounts of anthocyanins and quercetin derivatives. Phenolics strongly inhibited carbohydrate-digesting enzymes. The unripe fruit showed the highest antioxidant capacity and phenolic contents, and ripening led to a decrease in all these compounds. Ready-to-consume fruits were shown to be very rich sources of polyphenols, especially anthocyanins, and an important source of ellagitannins, comparable to the berries.

Evaluation of the diuretic activity of the ethanolic extract of Geranium seemannii Peyr. in Wistar rats

BackgroundAlthough Geranium seemannii Peyr. is widely used in Mexican traditional medicine, there is as yet no scientific study to explore the validity of this practice. Therefore, the aim of the present study was to evaluate the diuretic activity of the ethanolic extract of G. seemannii Peyr. to provide evidence about its effect. MethodsG. seemannii Peyr. was orally administered to adult male Wistar rats at 25 and 50 mg/kg, and its diuretic activity was evaluated and compared to the reference drug furosemide (20 mg/kg, administered intraperitoneally). Acute toxicity and lethality (LD50) of the extract were assessed. ResultsCompared to control rats, there was significantly higher urinary output, as well as sodium, potassium and chloride ion excretion, in animals administered the ethanolic extract of G. seemannii Peyr. This effect was dose dependent, and there was no evidence of either acute toxicity or lethality with twice the maximum dose employed. DiscussionThe diuretic activity of some plants has been attributed to the presence of flavonoids, and G. seemannii Peyr. has a relatively large concentration of ellagitannins. This could be responsible for the effect demonstrated herein, which was similar to that produced by the reference drug furosemide. The mechanism of action of furosemide is by inducing a loss of water through the inhibition of NaCl reabsorption. The results suggest that this receptor-mediated mechanism may account for the diuretic effect of G. seemannii Peyr. as well. ConclusionThe findings in the present work support the possible use of G. seemannii Peyr as a diuretic agent and, representing the first report of the diuretic activity of this specie.

Relation between volatile composition, ellagitannin content and sensory perception of oak wood chips representing different toasting processes

The evolution of both volatile and nonvolatile (ellagitannins) compounds extracted from oak wood chips while being macerated for 3 months in wine model solution with eight different commercial chips [Toasted LT (Light Toast), LT+ (Light plus Toast), MT (Medium Toast), MT+ (Medium plus Toast), HT (Heavy Toast), Noisette, Special) and un-toasted (UN)] was studied. Sensory analysis concerning vanilla, spicy, overall woody, astringency, bitterness and sweetness descriptors was conducted in parallel. A 2-month time is needed for the maximum extraction of ellagitannins and of furfural compound. Relating to other volatile compounds, their concentration increased progressively over time. Spicy, woody and vanilla aromas as well as sweetness perception increased during contact time with oak wood. Additionally to pyrolytic toasting stage, watering process during toasting influences significantly oak wood composition (lactones, vanillin guaiacol compounds and ellagitannins). Correlation analysis between chemical and sensory data demonstrated significant correlations between chemical and sensory parameters and provides some insight into the implication of volatile and nonvolatile composition on the final quality perception of astringency. A predictive model between astringency intensity and ellagitannins, furfural, guaiacol and methyl guaiacol contents was established. Ellagitannins levels explained 45 %, guaiacol and methyl guaiacol contents interpreted 13.20 and 8.86 %, respectively, whereas furfural levels justified 5.66 % of the total astringency variance.

Ellagitannins: defences of Betula nana against Epirrita autumnata folivory?

The induced resistance of the subarctic mountain birch Betula pubescens ssp. czerepanovii is a well‐characterized phenomenon, whereas the induced responses of Betula nana L., one of the parental species of mountain birch, have not yet been characterized. Betula nana is more resistant to several classes of insectivorous herbivores than the mountain birch, although the mechanisms responsible for the better ability to resist herbivores are not known. The present study aimed to determine the metabolic changes that are induced by early season herbivory in B. nana leaves and to study the effects of rapidly induced resistance on the growth of Epirrita autumnata larvae. Defoliation of B. nana was accomplished by E. autumnata larvae and leaf samples for chemical analyses were collected when the defoliating larvae were at their third and fifth instar. At the same time, laboratory assays for the growth and consumption rates of E. autumnata larvae were conducted. The wounding of leaves by E. autumna larvae induced the production of ellagitannins (ETs) in B. nana. Intriguingly, the concentrations of protein‐bound amino acids were also induced by herbivory; however, an increase in proteins was not mirrored in the growth rate of larvae, which was less on the induced foliage. The decreased growth rate of larvae was apparently linked to the increased concentrations of oxidatively‐active ETs and the high concentration of ETs may explain the better resistance of this parental species compared with the hybrid mountain birch with its lower levels of ETs.

Total phenolics, anthocyanins, ellagitannins content and radical scavenging activity of raspberries during ripening

Total phenolics, anthocyanins, ellagitannins content and radical scavenging activity of raspberries during ripening

Antibacterial Effects of Ellagitannins from Acalypha wilkesiana var. macafeana hort.: Surface Morphology Analysis with Environmental Scanning Electron Microcopy and Synergy with Antibiotics

The present study served to gain further insight into the bactericidal effects of ellagitannins from Acalypha wilkesiana var. macafeana hort. against pathogenic bacteria. Ellagitannins from the aerial parts of A. wilkesiana var. macafeana hort. (EAW) inhibited the growth of Bacillus cereus (ATCC 11778), Bacillus subtilis (ATCC 6633), Staphylococcus aureus (ATCC 11632) and Methicillin-resistant Staphylococcus aureus (MRSA) clinical strain with inhibition zones equal to 11.01 ± 1.53 mm, 16.63 ± 0.11 mm, 11.40 ± 1.10 mm and 8.22 ± 0.19 mm, respectively. The minimal inhibition concentration and the minimal bactericidal concentration of ellagitannins from A. wilkesiana var. macafeana hort. (EAW) against MRSA were 750 µg/mL and 3000 µg/mL, respectively. We then examined the synergistic effect of EAW with three antibiotics, i.e. ampicillin, streptomycin and tetracycline, via the checkerboard assay and time-kill assay and observed that EAW is synergistic with ampicillin against S. aureus (ATCC 11632). Environmental electron scanning microscopy analysis showed cell lysis against S. aureus (ATCC 11632) upon treatment with the ellagitannin fraction. The ellagitannin fraction from A. wilkesiana var. macafeana hort. is bactericidal against gram-positive bacteria tested and works synergistically with ampicillin against S. aureus. Morphology analysis of the cell suggests that the bactericidal property of the ellagitannin fraction mechanism involves lysis of the cell wall. In summary, our studies demonstrate that A. wilkesiana var. macafeana hort. produces bactericidal ellagitannins of clinical and/or cosmetological value.

Antioxidant capacity, scavenger activity, and ellagitannins content from commercial oak pieces used in winemaking

In 2005, the European Union authorized the use of oak wood pieces in winemaking, and consequently, the addition of oak chips has been generalized. Thus, the antioxidant capacity, scavenger activity, and ellagitannins content from fourteen different commercial oak wood pieces (Quercus spp.) that can be found on the Portuguese market as alternatives to barrels for aging wines were studied. Commercial oak wood pieces samples from Quercus petraea had significantly higher antioxidant activity values than the pieces from Quercus alba species. In general, antioxidant capacity and scavenging activity decrease with the toasting level of the oak wood pieces samples analyzed. A similar effect was detected in the individual ellagitannin content studied. On the other hand, with the toasting process, the total phenolic content and the ellagic acid concentration increased. Finally, a correlation analysis revealed that ellagitannins contribute to the antioxidant capacity of oak wood pieces studied. From the data presented in this paper, antioxidant capacity and ellagitannin content of the oak wood pieces studied have been clearly related either to the oak wood species used, particle size, or to toasting levels.

Color, Ellagitannins, Anthocyanins, and Antioxidant Activity of Andean Blackberry (Rubus glaucus Benth.) Wines

Twenty-eight blackberry ( Rubus glaucus Benth.) wines elaborated under different processing conditions were analyzed for total phenolics, ellagitannins, anthocyanins, color, and antioxidant activity. Ellagitannins were the main phenolic compounds and the most determinant factor in the antioxidant capacity of wines (r = 0.980). The major anthocyanins were cyanidin 3-rutinoside (64 ± 6%) and cyanidin 3-glucoside (19 ± 4%), followed by several minor compounds (17 ± 4%). Two of them were native blackberry anthocyanins, namely, cyanidin 3-rutinoside-5-glucoside and cyanidin 3-xylorutinoside. The remaining seven compounds were anthocyanin-related pigments generated during and after the alcoholic fermentation, identified as A-type and B-type vitisins and hydroxyphenylpyranoanthocyanins. The presence of fruit solids in contact with the liquid fraction during fermentation and the ratio of water to fruit employed in the preparation of the musts had a great impact on the content of ellagitannins, total phenolics, and the antioxidant activity of wines and a minor impact on their color and anthocyanin composition.

Metabolism of Oak Leaf Ellagitannins and Urolithin Production in Beef Cattle

Oak leaves have a high concentration of ellagitannins. These phytochemicals can be beneficial or poisonous to animals. Beef cattle are often intoxicated by oak leaf consumption, particularly after suffering feed restriction. The severity of the poisoning has recently been associated with the ruminal microbiota, as different bacterial populations were found in animals that tolerated oak leaves and in those that showed clinical and pathological signs of toxicity. Intoxication has previously been linked to the production of phenolic metabolites, particularly catechol, phloroglucinol, and resorcinol. This suggested that the microbial metabolism of ellagitannins could also be associated with its tolerance or intoxication in different animals. Therefore, it is essential to understand the metabolism of ellagitannins in cattle. Here we show that ellagitannins are metabolized in the cattle rumen to urolithins. Different urolithins were detected in ruminal fluid, feces, urine, and plasma. Oak leaf ellagitannins declined as they were converted to urolithins, mainly isourolithin A and urolithin B, by the ruminal and fecal microbiota. Urolithin aglycons were observed in rumen and feces, and glucuronide and sulfate derivatives were detected in plasma and urine. Sulfate derivatives were the main metabolites detected in plasma, while glucuronide derivatives were the main ones in urine. The main urolithins produced in cattle were isourolithin A and urolithin B. This is a relevant difference from the monogastric mammals studied previously in which urolithin A was the main metabolite produced. Low molecular weight phenolics of the benzoic, phenylacetic, and phenylpropionic groups and metabolites such as catechol, resorcinol, and related compounds were also detected. There was a large variability in the kinetics of production of these metabolites in individual animals, although they produced similar metabolites in all cases. This large variability could be associated with the large variability in the rumen and intestine microbiota that has previously been observed. Further studies are needed to demonstrate if the efficiency in the metabolism of ellagitannins by the microbiota could explain the differences observed in susceptibility to intoxication by the different animals.

Potential dietary sources of ellagic acid and other antioxidants among fruits consumed in Brazil: Jabuticaba (Myrciaria jaboticaba (Vell.) Berg)

The objectives of this study were (1) to evaluate the content of ellagic acid in fruits consumed by the Brazilian population, including native ones; (2) to further characterize rich sources in relation to ascorbic acid, phenolics contents and in vitro antioxidant capacity; and (3) to study the distribution and effect of ripening stage on ellagitannins content of jabuticaba (Myrciaria jaboticaba). The content of free ellagic acid and ellagic acid derivatives such as ellagitannins was analyzed using high-performance liquid chromatography (HPLC). Ellagic acid was detected in 10 out of a total of 35 fruits analyzed. The content of free ellagic acid in fruits varied from 0.0028 to 0.085 g kg(-1) (FW) and total ellagic acid varied from 0.215 to 3.11 g kg(-1) (FW). All the seven fruits belonging to the Myrtaceae family evaluated in this study presented high contents of ellagitannins in their composition, with jabuticaba, grumixama and cambuci (all native from Brazil) showing the highest total ellagic acid contents. Jabuticaba, the most consumed in Brazil among those and already adapted to commercial plantations, contained concentrated phenolics compounds, including ellagitannins, in the peel. Anthocyanins (cyanidin derivatives) increased significantly through ripening of jabuticaba and were not present in the pulp or seeds. Samples collected from three different locations during summer, winter and spring had total ellagic contents varying from 1.88 to 3.31 g kg(-1) (FW). The decrease in ellagic acid content with ripening was more accentuated for pulp (eight times) compared to seeds (2.3 times) and peel (2.0 times). These results showed the potential of jabuticaba as dietary source of ellagic acid and reinforced consumption of the whole fruit by the population.

Anti-inflammatory Effects of Polyphenolic-Enriched Red Raspberry Extract in an Antigen-Induced Arthritis Rat Model

The red raspberry ( Rubus idaeus ) fruit contains bioactive polyphenols including anthocyanins and ellagitannins with reported anti-inflammatory properties. This study sought to investigate the cartilage-protecting and anti-inflammatory effects of a polyphenolic-enriched red raspberry extract (RRE; standardized to total polyphenol, anthocyanin, and ellagitannin contents) using (1) an in vitro bovine nasal explant cell culture model and (2) an in vivo adjuvant-induced arthritis rat model. RRE contained 20% total polyphenols (as gallic acid equivalents), 5% anthocyanins (as cyanidin-3-glucoside equivalents), and 9.25% ellagitannins (as ellagic acid equivalents). In the in vitro studies, bovine nasal explants were stimulated with 10 ng/mL IL-1β to induce the release of proteoglycan and type II collagen. On treatment with RRE (50 μg/mL), there was a decrease in the rate of degradation of both proteoglycan and type II collagen. In the in vivo antigen-induced arthritis rat model, animals were gavaged daily with RRE (at doses of 30 and 120 mg/kg, respectively) for 30 days after adjuvant injection (750 μg of Mycobacterium tuberculosis suspension in squalene). At the higher dose, animals treated with RRE had a lower incidence and severity of arthritis compared to control animals. Also, histological analyses revealed significant inhibition of inflammation, pannus formation, cartilage damage, and bone resorption by RRE. This study suggests that red raspberry polyphenols may afford cartilage protection and/or modulate the onset and severity of arthritis.

Hydrolyzable tannins of tamaricaceous plants. IV: Micropropagation and ellagitannin production in shoot cultures of Tamarix tetrandra

Shoot cultures of Tamarix tetrandra on Linsmaier–Skoog (LS) agar medium with 30 g l −1 sucrose, 2.13 mg l −1 indoleacetic acid and 2.25 mg l −1 benzyl adenine produced ellagitannins found in intact plants of the Tamaricaceae. This was demonstrated by the isolation of 14 monomeric–tetrameric ellagitannins from the aq. Me 2CO extract of the cultured tissues. This is the first report on the production of ellagitannin tetramers by plant tissue culture. The effects of light and certain medium constituents on tissue growth and ellagitannin production were examined. The contents of representative tannins of different types [i.e., tellimagrandin II (monomer), hirtellin A (linear GOG-type dimer), hirtellin B (hellinoyl-type dimer), hirtellin C (macrocyclic-type dimer), and hirtellin T1 (linear GOG-type trimer)] in the resultant tissues in response to these factors were estimated by HPLC, and the optimal condition for production of these tannins were established. Shoots cultured on LS hormone-free medium promoted root development, and regenerated plants could adapt to ordinary soil and climate. Acclimatized and intact T. tetrandra plants that were collected in November and May, respectively, demonstrated seasonal differences in individual ellagitannin contents. HPLC comparison of individual ellagitannin contents in different plant materials (i.e., leaves, stems, and roots) of intact T. tetrandra plants is also reported. The results are discussed with respect to cellular deposition and biosynthetic relationship of tannins.

Differential effectiveness of berry polyphenols as anti-giardial agents

SUMMARYFollowing previous work on the anti-giardial effect of blueberry polyphenols, a range of polyphenol-rich extracts from berries and other fruits was screened for their ability to kill Giardia duodenalis, an intestinal parasite of humans. Polyphenol-rich extracts were prepared from berries using solid-phase extraction and applied to trophozoites of Giardia duodenalis grown in vitro. All berry extracts caused inhibition at 166 μg gallic acid equivalents (GAE)/ml phenol content but extracts from strawberry, arctic bramble, blackberry and cloudberry were as effective as the currently used drug, metronidazole, causing complete trophozoite mortality in vitro. Cloudberry extracts were found to be the most effective causing effectively complete trophozoite mortality at 66 μg GAE/ml. The polyphenol composition of the more effective berry extracts suggested that the presence of ellagitannins could be an important factor. However, the potency of cloudberry could be related to high ellagitannin content but also to the presence of substantial amounts of unconjugated p-coumaric acid and benzoic acid. These in vitro effects occur at concentrations easily achievable in the gut after berry ingestion and we discuss the likelihood that berry extracts could be effective anti-giardial agents in vivo.

Impact of Concentration of Ellagitannins in Oak Wood on Their Levels and Organoleptic Influence in Red Wine

Some wood substances such as ellagitannins can be extracted during wine aging in oak barrels. The level of these hydrolyzable tannins in wine depends of some parameters of oak wood. Their impact on the organoleptic perception of red wine is poorly known. In our research, oak staves were classified in three different groups according to their level of ellagitannins estimated by NIRS (near infrared spectroscopy) online procedure (Oakscan). First, the ellagitannin level and composition were determine for each classified stave and an excellent correlation between the NIRS classification (low, medium and high potential level of ellagitannin) and the ellagitannin content estimated by HPLC-UV was found. Each different group of NIRS classified staves was then added to red wine during its aging in a stainless tank, and the extraction and evolution of the ellagitannins were monitored. A good correlation between the NIRS classification and the concentration of ellagitannins in red wine aging in contact with the classified staves was observed. The influence of levels of ellagitannins on the resulting wine perception was estimated by a trained judge's panel, and it reveals that the level of ellagitannins in wine has an impact on the roundness and amplitude of the red wine.

Ent-Eudesmane sesquiterpenoids, galloyl esters of the oak lactone precursor, and a 3- O-methylellagic acid glycoside from the wood of Platycarya strobilacea

ent-Eudesmane sesquiterpenoids, 8,11-dihydroxy-2,4-cycloeudesmane, 11-hydroxy-2,4-cycloeudesman-8-one and 2,4-cyclo-7(11)-eudesmen-8-one, were isolated from the wood of Platycarya strobilacea, which has been used as an aromatic tree since at least the 18th century. On charring the wood, 2,4-cyclo-7(11)-eudesmen-8-one was detected in the smoke. In the charred wood, the concentrations of ellagitannins, such as galloyl pedunculagin, dramatically decreased, whereas concentrations of pentagalloyl glucose, and other gallotannins were relatively stable. In addition, two other compounds, the 6′- O- m- and p-digalloyl oak lactone precursor and the 3- O-methylellagic acid 4′- O-(4″- O-galloyl)-xylopyranoside, were isolated from the charred wood along with m- and p-digallic acid.

Effects of air and soil temperatures on the chemical composition of fruit and agronomic performance in strawberry (Fragaria ananassa Duch.)

SummaryThe effects of different air and soil temperatures on the levels of bioactive components in strawberry fruit (cv. Elsanta) were studied under Winter greenhouse conditions, as were agronomic parameters such as fruit yield, fruit size, and leaf area. The following three temperature Treatments were applied: A, cool (day/night: 16°C/12°C); B, warm (day/night: 22°C/16°C); and C, warm with soil heating to 26°C during the day. Increasing the air temperature in the greenhouse, or the soil temperature, decreased the average fruit weight. Fruit quality attributes such as dry matter and soluble solids contents, and titratable acidity, were not significantly influenced by the different treatments. Strawberries grown in the cool environment (Treatment A) had a lower anti-oxidant capacity, in terms of their total phenolics (TP) content, trolox equivalent anti-oxidant capacity (TEAC), and oxygen radical absorbance capacity (ORAC), than strawberries produced in the warmer environment (Treatment B). This was due to lower concentrations of total monomeric anthocyanins, total pro-anthocyanidins, total ellagitannins, and kaempferol 3-glucoside-malonate. On the other hand, ascorbic acid concentrations in fruit grown in the cooler environment were higher compared to fruit grown in the warmer environment. An increase in soil temperature in the warmer environment (Treatment C) did not result in any additional accumulation of anthocyanins, or any other phenolics in the fruit, except for p-coumaroyl glucose. However, the concentrations of pro-anthocyanidins were even lower in fruit grown with heated soil. These results showed that air and soil temperatures have a significant influence on the phenolics composition of strawberries.