Ellagitannin content and anti-enterohemorrhagic Escherichia coli activity of aqueous extracts derived from commercial pomegranate products

This study compared the efficacy of aqueous extracts of commercially available pomegranate peel products and a juice powder in inhibiting the growth of two enterohemorrhagic Escherichia coli strains. Cell suspension of each E. coli strain (5 Log CFU/ml) was added into tryptic soy broth amended with 9 or 23% of each extract prepared with two different methods. After treatment for 5, 10, and 24 h at 25 °C, surviving E. coli cells were enumerated on tryptic soy agar to determine cell population reduction compared to the controls. The concentrations of six different ellagitannins and titratable activity in each treatment system were determined and correlated to E. coli cell population reduction. The extracts from three powdered pomegranate peels caused a significantly greater (p ≤ 0.05) reduction in E. coli population than the extract from the whole peel and juice powder. The higher dose of extracts resulted in a greater cell population reduction than the lower dose. The level of E. coli population reduction correlated positively with the total ellagitannins content (R2 0.67-0.98) and the titratable acidity (R2 0.69-0.98) in the treatment systems. The study suggests that pomegranate peels are promising natural additives or preservatives to control pathogens like EHEC.

Optimization of accelerated solvent extraction of ellagitannins in black raspberry seeds using artificial neural network coupled with genetic algorithm

This study aimed to identify ellagitannins in black raspberry seeds (BRS) and to optimize accelerated solvent extraction of ellagitannins using an artificial neural network (ANN) coupled with genetic algorithm. Fifteen monomeric and dimeric ellagitannins were identified in BRS. For ANN modeling, extraction time, extraction temperature, and solvent concentration were set as input variables, and total ellagitannin content was set as output variable. The trained ANN had a mean squared error value of 0.0102 and a regression correlation coefficient of 0.9988. The predicted optimal extraction conditions for maximum total ellagitannin content were 63.7% acetone, 4.21 min, and 43.9 °C. The actual total ellagitannin content under the optimal extraction conditions was 13.4 ± 0.0 mg/g dry weight, and the prediction error was 0.75 ± 0.27%. This study is the first attempt to analyze the composition of ellagitannins in BRS and to determine optimal extraction conditions for maximum total ellagitannin content from BRS.

Isolation of a new taste-active brandy tannin A: Structural elucidation, quantitation and sensory assessment

Enjoying a glass of spirits can be one of the delights of life. While it is well known that their taste improves during barrel aging, the molecular explanations of this phenomenon remain largely unknown. The present work aimed at searching for taste-active compounds formed in spirits during aging. An untargeted metabolomic approach using HRMS was applied on "eau-de-vie" of cognac. A fractionation protocol was then performed on brandies to isolate a targeted compound. By using HRMS and NMR, its structure was elucidated for the first time. This new ellagitannin, called brandy tannin A, considerably increased the sweetness of spirits at 2 mg/L. After development of an LC-HRMS quantitation method, it was assayed in various spirits and was detected mainly in cognacs up to 7 mg/L. These findings demonstrate the sensory contribution of this compound and more generally the relevance of combining metabolomics and separative techniques to purify new taste-active compounds.

Unique distribution of ellagitannins in ripe strawberry fruit revealed by mass spectrometry imaging

Ellagitannins (ETs) are hydrolysable tannins composed of a polyol core, primarily glucose, which is esterified with hexahydroxydiphenic acid (HHDP), and in some cases, gallic acid. ETs are the major phenolic compounds found in strawberries and may contribute to the health-related properties of strawberries, because of their strong antioxidative activity. However, their distribution in the strawberry fruit remains unclear. In this study, matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI–MSI) was used to visualize ETs in ripe strawberry fruits. Five peaks, corresponding to the m/z values of ET [M−H]⁻ ions detected in the MALDI–MS spectrum of strawberry extracts, were identified as strictinin, pedunculagin, casuarictin, davuriicin M₁, and an unknown ET using MALDI–tandem MS (MS/MS). In addition, liquid chromatography–electrospray ionization–MS/MS of the extracts revealed the presence of pedunculagin isomers and the unknown ET. Ion images of these five ETs were reconstructed using MALDI–MSI. Strictinin was widely distributed in and around the achene seed coats, while the other ETs were dispersed in and around the seed coats, and at the bottom of the receptacle; pedunculagin was distributed in the epidermis and pith, whereas casuarictin, the unknown ET, and davuriicin M₁ were distributed in the pith. Moreover, MALDI–MSI of a casuarictin standard indicated that in-source fragmentation weakly affected the ion images. The results suggest that the distribution of ETs depends on the presence or absence of their constituents, namely galloyl units, HHDP, and bis-HHDP. To the best of my knowledge, this is the first report on the visualization of ETs in plant tissues using MSI, MALDI–MSI may be a useful tool for analyzing the distribution of ETs in the strawberry fruit.

•

The ellagitannins (ETs) in strawberry fruits were identified.

•

MALDI-MS/MS and LC-MS/MS were used.

•

The ETs identified in the fruits were visualized using MALDI-MSI.

•

The ETs showed unique distributions in the seeds and the lower receptacle.

•

The distribution of ETs depends on their constituents: galloyl units and HHDP.

qNMR quantification of phenolic compounds in dry extract of Myrcia multiflora leaves and its antioxidant, anti-AGE, and enzymatic inhibition activities

Myrcia multiflora (Lam.) DC. is often used in Brazilian folk medicine to control diabetes. Analysis using HPLC-HRMS and NMR of the dry extract from the infusion of leaves of this species revealed twelve phenolic compounds. Among these compounds, chlorogenic acid (1), 4-O-caffeoylquinic acid (2), corilagin (3), chebulagic acid (4), pedunculagin (5), quercetin-3-O-β-2″-galloylglucoside (7), and kaempferol-3-O-rhamnoside (12) are described for the first time in this matrix. Furthermore, six compounds were quantified using qNMR. The compounds in the dry extracts are 3, 6 (myricetin-3-O-d-glucoside), 8 (myricitrin), 9 (hyperoside), 10 (guaijaverin) and 11 (quercitrin). These compounds may be considered chemical markers in this matrix. In addition, this extract presents activities of α-glucosidase inhibition (IC₅₀ = 79.9 μg mL^-1) and glycation in vitro (IC₅₀ = 10.2 μg mL^-1), in addition to antioxidant activity against DPPH and ABTS radicals (1,856.7 and 1,032.0 μmol TEq, respectively). This extract did not show significant cytotoxicity in human fibroblasts. Therefore, the enzymatic inhibition, anti-AGE (advanced glycation end-products) and antioxidant activities of Myrcia multiflora leaves corroborated its antidiabetic therapeutic potential and instigates future preclinical studies aimed at the treatment of diabetes mellitus and its complications.

Effect of agricultural practices, conventional vs organic, on the phytochemical composition of 'Kweli' and 'Tulameen' raspberries (Rubus idaeus L.)

Raspberries are rich in polyphenols but the impact of organic versus conventional agricultural practices on their phytochemical composition is not well known. This study aimed to analyse and compare the polyphenol accumulation in raspberries grown under both agricultural practices in the same edaphoclimatic conditions. Two raspberry cultivars 'Kweli' and 'Tulameen' were used. Under organic agricultural practices, the polyphenols levels increased for the 'Kweli' cultivar but decreased for the 'Tulameen' cultivar. 'Tulameen' cultivar grown under conventional agricultural practices contained higher anthocyanins levels than grown under organic agricultural practices while for the 'Kweli' cultivar no significant differences were observed between the two agricultural practices. 'Kweli' cultivar presented a significantly higher amount of ellagitannins and ellagic acid derivatives when compared to the 'Tulameen' cultivar under both agricultural practices. The effect of the agricultural practices on the raspberries' chemical profile was dependent on the cultivar and cannot be generalised.

Acute oral toxicity of the ellagitannin geraniin and a geraniin-enriched extract from Nephelium lappaceum L rind in Sprague Dawley rats

Despite the lack of its toxicity evaluation, traditional herbal products are being widely used for various health indications. Geraniin, an ellagitannin, is a bioactive compound found in many traditional herbal medicines. In spite its numerous health benefits ranging from anti-inflammatory, anti-hyperglycaemic, hepatoprotective, anti-cancer and anti-microbial, no toxicity data on geraniin is available. The objective of this study is to evaluate the acute oral toxicity of geraniin and an enriched geraniin-extract of Nephelium lappaceum L rind. This study followed the guidelines of the OECD 423 acute oral toxicity test. Subsequent to a single oral administration of the test compounds, the rats were observed for 14 days for signs of toxicity and mortality. Following euthanasia, full blood count, biochemistry of blood and histopathology assessment of organs were carried out. All parameters analysed indicated insignificant difference compared to control. The LD₅₀ cut-off values for both geraniin and geraniin-enriched extract was established to be 2000 mg/kg b. w., following a single oral dose. It was however observed that the hepatocytes of three geraniin-administered rats exhibited a ‘foamy appearance’. As such, the no-observed-adverse-effect level of geraniin is below 2000 mg/kg, while that of geraniin-enriched extract is up to 2000 mg/kg. Further detailed toxicity studies are required to establish geraniin or its enriched extract from Nephelium lappaceum L rind safe for human consumption.

Phenolic-enriched raspberry fruit extract (Rubus idaeus) resulted in lower weight gain, increased ambulatory activity, and elevated hepatic lipoprotein lipase and heme oxygenase-1 expression in male mice fed a high-fat diet

Red raspberries (Rubus idaeus) contain numerous phenolic compounds with purported health benefits. Raspberry ketone (4-(4-hydroxyphenyl)-2-butanone) is a primary raspberry flavor phenolic found in raspberries and is designated as a synthetic flavoring agent by the Food and Drug Administration. Synthetic raspberry ketone has been demonstrated to result in weight loss in rodents. We tested whether phenolic-enriched raspberry extracts, compared with raspberry ketone, would be more resilient to the metabolic alterations caused by an obesogenic diet. Male C57BL/6J mice (8 weeks old) received a daily oral dose of vehicle (VEH; 50% propylene glycol, 40% water, and 10% dimethyl sulfoxide), raspberry extract low (REL; 0.2 g/kg), raspberry extract high (REH; 2 g/kg), or raspberry ketone (RK; 0.2 g/kg). Coincident with daily dosing, mice were placed on a high-fat diet (45% fat). After 4 weeks, REH and RK reduced body weight gain (approximately 5%-9%) and white adipose mass (approximately 20%) compared with VEH. Hepatic gene expression of heme oxygenase-1 and lipoprotein lipase was upregulated in REH compared with VEH. Indirect calorimetry indicated that respiratory exchange ratio (CO₂ production to O₂ consumption) was lower, suggesting increased fat oxidation with all treatments. REH treatment increased total ambulatory behavior. Energy expenditure/lean mass was higher in REH compared with REL treatment. There were no treatment differences in cumulative intake, meal patterns, or hypothalamic feed-related gene expression. Our results suggest that raspberry ketone and a phenolic-enriched raspberry extract both have the capacity to prevent weight gain but differ in the preventative mechanisms for excess fat accumulation following high-fat diet exposure.

Hyal-1 inhibitors from the leaves of Phyllanthus muellerianus (Kuntze) Excell

ETHNOPHARMACOLOGICAL RELEVANCE

Leaves and twigs from Phyllanthus muellerianus Kuntze Excell are known to exert anti-inflammatory and antipyretic properties as well as wound healing properties. During a wide screening for human hyaluronidase-1 inhibitors from natural sources leaf extracts from P. muellerianus turned out to show basic anti-hyaluronidase activity. A detailed investigation of this effect should rationalize the potential anti-inflammatory activity of the extract for improved wound healing.

AIM OF THE STUDY

The following study aimed to characterize the anti-Hyal-1 activity of the extract from P. muellerianus and to pinpoint the responsible natural products responsible for this bioactivity.

MATERIALS AND METHODS

Using cell surface displayed human Hyal-1 on Escherichia coli, the activity of inhibitors was determined by the stains-all assay method. A hydroalcoholic extract PWE from P. muellerianus was subjected to bioactivity-guided fractionation. Active compounds were characterized by means of mass spectrometry and NMR.

RESULTS

PWE exerts a concentration dependent inhibition of Hyal-1 with an IC₅₀ of 80 μg/mL. Bioassay-guided fractionation revealed 13 compounds from the two most active fractions, mainly ellagitannins and flavonoid glycosides. The most activeHyal-1 inhibitor was found to be the ellagitannin chebulanin 10 (IC₅₀ 132 μM). This represents the first description of chebulanin in P. muellerianus.

CONCLUSIONS

The hydroalcoholic extract of P. muellerianus, as well as several subfractions obtained during bioassay-guided fractionation showed strong activity against Hyal-1. The main activity can be correlated to the ellagitanin chebulanin. Additionally, also synergistic effects are observed, indicating that the traditional use of aqueous extracts of P. muellerianus is justified, rather than the use of the isolated tannins. The traditional use of the plant as an anti-inflammatory agent for improved wound-healing can be rationalized by the anti-Hyal-1 activities of its constituents.

Metabolic profiling analysis of corilagin in vivo and in vitro using high-performance liquid chromatography quadrupole time-of-flight mass spectrometry

Corilagin is an Ellagitannin with favorable pharmacological activities. But there was no report regarding the metabolism of corilagin in vitro or in vivo. In this study, the metabolic profile of corilagin in rats as well as in rat intestinal bacteria and liver microsomes incubation system in vitro were investigated comprehensively for the first time. Consequently, with the aid of sensitive HPLC-Q-TOF-MS/MS, corilagin and its twenty-four metabolites (fourteen phase II conjugate metabolites of corilagin, three hydrolyzed metabolites EA, GA, M3 and their seven derived metabolites) were absolutely or tentatively identified in rat biological samples (urine, feces, plasma and tissues) after oral administration of corilagin. In vitro, the three hydrolyzed metabolites were identified in rat intestinal microflora and liver microsomes. These results demonstrated that corilagin itself not only could underwent extensive phase II metabolism in rats, but also could underwent hydrolysis reaction in rats as well as in rat intestinal bacteria and liver microsomes in vitro. This study is first report to identify phase II conjugate metabolites (except mono-methylate conjugated metabolites) of pure Ellagitannin and distribution of these metabolites in vivo. In addition, clear, detailed metabolic pathways of corilagin were shown to involve hydrolysis, methylation, glycosylation, reduction, glucuronidation and sulfation.

Comparison of polyphenol content and antioxidant capacity of strawberry fruit from 90 cultivars of Fragaria × ananassa Duch

Strawberry fruit is a valuable resource, rich in vitamins and polyphenolic compounds. These compounds have a broad spectrum of biological activity. The aim of this study was to evaluate the qualitative and quantitative composition of polyphenols in strawberry fruit from 90 cultivars of Fragaria × ananassa Duch. from two growing seasons. Eighty of them were analyzed for the first time (to the best of our knowledge). The identification of polyphenolics and other compounds was performed using UPLC-qTOF-MS/MS. Nine compounds were recorded for the first time in mature strawberry fruit. Antioxidant properties were also determined using DPPH and ABTS methods. Statistical analysis of the results was performed using principal component analysis. Tannins, especially ellagitannins with agrimoniin, as well as the total polyphenols, had the greatest influence on antioxidant activity in the ABTS test. Cultivars characterized by a high content of tannins and high antioxidant capacity were selected.

The ellagitannin HeT induces electrolyte leakage, calcium influx and the accumulation of nitric oxide and hydrogen peroxide in strawberry

HeT (1-0-galloyl-2,3; 4,6-bis-hexahydroxydiphenoyl-β-D-glucopyranose) is a penta-esterified ellagitannin obtained from strawberry leaves. Previous studies have shown that foliar application of HeT prior to inoculation with a virulent pathogen increases the resistance toward Colletotrichum acutatum in strawberry plants and to Xanthomonas citri subsp. citri in lemon plants. In this work we report that HeT induces an immediate leak of electrolytes, the hyperpolarization of the cellular membrane, a rapid Ca²⁺ influx to the cytoplasm during the first few seconds, which in turn modulates the accumulation of nitric oxide 5 min after treatment. At longer times, a biphasic accumulation of H₂O₂ with peaks at 2 and 5 h post treatment could be observed. In addition, HeT elicited the increase of alternative oxidase capacity during the first 12 h post treatment.

Geraniin suppresses tumor cell growth and triggers apoptosis in human glioma via inhibition of STAT3 signaling

Natural phytochemicals are attracting increasing interest as anticancer agents. The aim of this study is to evaluate the therapeutic potential of geraniin, a major ellagitannin extracted from Geranium sibiricum L., in human glioma. Human U87 and LN229 glioma cells were treated with different concentrations of geraniin, and cell viability, apoptosis, and gene expression were assessed. The involvement of STAT3 signaling in the action of geraniin was examined. We found that geraniin treatment for 48 h significantly (P < 0.05) impaired the phosphorylation of STAT3 and reduced the expression of downstream target genes Bcl-xL, Mcl-1, Bcl-2, and cyclin D1. Exposure to geraniin led to a concentration-dependent decline in cell viability and increase in apoptosis in glioma cells, but had no significant impact on the viability of normal human astrocytes. Measurement of caspase-3 activity showed that geraniin-treated U87 and LN229 cells showed a 1.8-2.5-fold higher caspase-3 activity than control cells. Overexpression of constitutively active STAT3 significantly (P < 0.05) reversed geraniin-mediated growth suppression and apoptosis, which was accompanied by restoration of Bcl-xL, Mcl-1, Bcl-2, and cyclin D1 expression. In an xenograft tumor mouse model, geraniin treatment significantly retarded tumor growth and induced apoptosis. Western blot analysis confirmed the suppression of STAT3 phosphorylation in glioma xenograft tumors by geraniin. Taken together, these data suggest that geraniin exerts growth-suppressive and pro-apoptotic effects on glioma cells via inhibition of STAT3 signaling and may have therapeutic benefits in malignant gliomas.

Cytotoxic and Chemopreventive Effects of Gemin D Against Different Mutagens Using In Vitro and In Vivo Assays

BACKGROUND

Gemin D (GD) is an ellagitannin found in several plant species rich in phenolic compounds. Its many beneficial properties include antioxidant and antitumoral.

OBJECTIVE

The present study assessed the genotoxicity, cytotoxicity, antigenotoxicity, and anticytotoxicity of GD by in vitro and in vivo assays.

METHOD

The Ames mutagenicity assay in Salmonella typhimurium, Micronucleus and Comet tests in mice were used to evaluate the biological activities mentioned above. To assess the GD's protective effects against DNA damage induced by different mutagens we performed co-, pre- and/or post-treatment in these assays.

RESULTS

There was no genotoxic effect of GD via Ames and Micronucleus tests, but in the Comet assay the highest dose induced DNA damage. This same highest dose presented a significant cytotoxicity in mice. In the antigenotoxicity, GD protected DNA against the action of 4-nitroquinoline-1-oxide and sodium azide by Ames test, and also against the harmful action of cyclophosphamide in pre- and co-treatment by Micronucleus and Comet tests, but it did not protect DNA in post-treatment. Regarding to anticytotoxicity, GD provoked an anticytotoxic effect only during pre-treatment.

CONCLUSION

Therefore, GD showed relevant antigenotoxic, anticytotoxic and cytotoxic effects, which indicate that it may be a probable candidate for chemoprevention or for the development of new cancer therapies.

Distribution and content of ellagitannins in Finnish plant species

The results of a screening study, in which a total of 82 Finnish plant species were studied for their ellagitannin composition and content, are presented. The total ellagitannin content was determined by HPLC-DAD, the detected ellagitannins were further characterized by HPLC-ESI-QTOF-MS and divided into four structurally different sub-groups. Thirty plant species were found to contain ellagitannins and the ellagitannin content in the crude extracts varied from few mgg(-1) to over a hundred mgg(-1). Plant families that were rich in ellagitannins (>90mgg(-1) of the crude extract) were Onagraceae, Lyhtraceae, Geraniaceae, Elaeagnaceae, Fagaceae and some species from Rosaceae. Plant species that contained moderate amounts of ellagitannins (31-89mgg(-1) of the crude extract) were representatives of the family Rosaceae. Plant species that contained low amounts of ellagitannins (1-30mgg(-1) of the crude extract) were representatives of the families Betulaceae and Myricaceae. The specific ellagitannin composition of the species allowed their chemotaxonomic classification and the comparison between the older Cronquist's classification and the nowadays preferred Angiosperm Phylogeny Group classification.

Antifungal ellagitannin isolated from Euphorbia antisyphilitica Zucc

OBJECTIVE

To study antifungal activity of a new ellagitannin isolated from the plant residues of Euphorbia antisyphilitica (E. antisyphilitica) Zucc in the wax extraction process.

METHODS

An extract was prepared from dehydrated and pulverized residues and fractionated by liquid chromatography on Amberilte XAD-16, until obtained an ellagitannin-rich ethanolic fraction which was treated by rotaevaporation to recover the ellagitannin as fine powder. An aqueous solution was prepared and treated through ionic exchange liquid chromatography (Q XL) and gel permeation chromatography (G 25). The ellagitannin-rich fraction was thermogravimetrically evaluated (TGA and DTA) to test the thermo-stability of ellagic acid (monomeric unit). Then ellagitannin powder was analyzed by infrared spectrospcopy to determinate the functional groups and, also mass spectroscopy was used to determine the molecular ion.

RESULTS

The principal functional groups of ellagitannin were determined, the molecular weight was 860.7 g/mol; and an effective antifungal activity against phytopathogenic fungi was demonstrated.

CONCLUSIONS

It can be concluded that the new ellagitannin (860.7 g/mol) isolated from E. antisyphilitica Zucc is an effective antifungal agent against Alternaria alternata, Fusarium oxyzporum, Colletotrichum gloeosporoides and Rhizoctnia solani.

Metabolite profiling analysis of FR429, an ellagitannin purified from Polygonum capitatum, in rat and human liver microsomes, cytosol and rat primary hepatocytes in vitro

FR429, an ellagitannin (a type of polyphenol), is isolated and purified from Polygonum capitatum Buch.-Ham.ex D. Don which is the original herbal medicine of the "Re-Lin-Qing" formula used clinically to treat urinary tract infection in China. FR429 has been investigated for its antitumor potential in tumor-bearing nude mice in vivo, but its in vitro anti-tumor effect in hepatoma cell lines was low. Thus, it was of our interest to investigate its metabolism pathways for supporting its in vivo antitumor potential. The metabolic profiles of FR429 were studied in vitro by liquid chromatography coupled to ion trap time-of-flight mass spectrometry. Total eight metabolites were identified in rat and human liver microsomes, cytosol, and rat primary hepatocytes in vitro. Ellagic acid, a reported anti-angiogenic agent, was one of the main metabolites in these biological matrices. Methylated metabolites catalyzed by catechol-O-methyl transferase (COMT) were observed mainly in the in vitro incubation with rat liver cytosol, which was verified by using a COMT specific inhibitor entacapone and supported by molecular docking analysis. Methylated and sulfated metabolites were also found in rat primary hepatocytes in a time-dependent manner. In conclusion, the in vitro metabolism pathways of FR429 were hydrolysis, methylation and sulfation. The anti-tumor effects of its major metabolites should be further studied.

Assessment of pomegranate wine lees as a valuable source for the recovery of (poly)phenolic compounds

Wine lees are the residue formed at the bottom of recipients containing wine after fermentation and are mainly composed of yeast. They can be applied for the recovery of value-added phytochemicals owing to the ability of yeast to form molecular interactions with (poly)phenolic compounds. This study aimed to evaluate the potential use of lees obtained as by-products after winemaking of pomegranate (Punica granatum L.) juice. Pomegranate wine lees showed high both phenolic content (about 30 mg GAE/g dry matter) and antioxidant capacity by DPPH and ABTS(+) assays. The phytochemical screening of this by-product by UHPLC-ESI-MS(n) allowed the identification of up to 39 chemicals, being hydrolysable tannins and anthocyanins the predominant structures. Ellagic acid and gallic acid were present in high amounts. In addition, mineral composition was also assessed. Overall, pomegranate wine lees resulted in a promising source for the recovery of bioactive polyphenols with potential applications in different industrial fields.

Fungal biodegradation of pomegranate ellagitannins

Ellagitannins (ETs) are phytochemicals derived from secondary metabolism associated to defense system, with complex chemical structures, which have high participation during all stages of protection against microbial infection. In this study, we report the fungal biodegradation of a bioactive ET, named punicaline which was recovered and purified from pomegranate peels and used as carbon source in solid-state culture (SSC) using polyurethane as solid support. SSC was kinetically monitored during 36 h of incubation time. ETs and glycosides consumption were spectrophotometrically determined. Ellagic acid (EA) accumulation was analyzed by HPLC. Several enzymatic activities were assayed (cellulase, xylanase, β-glucosydase, polyphenoloxidase, tannase, and ET hydrolyzing activities). The consumption levels of ETs and glycosides were 66 and 40%, while EA accumulation reached 42.02 mg g(-1). A differential pattern of enzymatic activities was found; evidence from our studies suggests that the ET hydrolyzing activity is directly associated to EA accumulation, and production of this enzyme may represent the most critical step to successfully develop a bioprocess for production of an important bioactive compound, the EA.