T-cinnamic Acid Research Articles

Effect of Light and Dark on the Phenolic Compound Accumulation in Tartary Buckwheat Hairy Roots Overexpressing ZmLC.

Fagopyrum tataricum ‘Hokkai T10′ is a buckwheat cultivar capable of producing large amounts of phenolic compounds, including flavonoids (anthocyanins), phenolic acids, and catechin, which have antioxidant, anticancer, and anti-inflammatory properties. In the present study, we revealed that the maize transcription factor Lc increased the accumulation of phenolic compounds, including sinapic acid, 4-hydroxybenzonate, t-cinnamic acid, and rutin, in Hokkai T10 hairy roots cultured under long-photoperiod (16 h light and 8 h dark) conditions. The transcription factor upregulated phenylpropanoid and flavonoid biosynthesis pathway genes, yielding total phenolic contents reaching 27.0 ± 3.30 mg g−1 dry weight, 163% greater than the total flavonoid content produced by a GUS-overexpressing line (control). In contrast, when cultured under continuous darkness, the phenolic accumulation was not significantly different between the ZmLC-overexpressing hairy roots and the control. These findings suggest that the transcription factor (ZmLC) activity may be light-responsive in the ZmLC-overexpressing hairy roots of F. tataricum, triggering activation of the phenylpropanoid and flavonoid biosynthesis pathways. Further studies are required on the optimization of light intensity in ZmLC-overexpressing hairy roots of F. tataricum to enhance the production of phenolic compounds.

Polyphenolic profiles in edible Annona spp. using high-performance liquid chromatography (HPLC-MS/MS)

Polyphenolic compounds of fruits of various plant species play an important role in physiological functions related to human health. Polyphenols have important biological activities like antioxidant activity which helps in normal functioning of human body. The objective of this study was to investigate the profiles of polyphenolic compounds in different edible Annona spp. fruits. Total of eighteen identified individual phenolic compounds were found, among which p-coumaric acid (321.53-90.17µg g-1FW), o-coumaric acid (70.80-19.00µg g-1FW), 2,4-dihydroxybenzoic acid (39.49-10.43µg g-1FW), caffeic acid (35.26-3.43µg g-1FW), gentisic acid (24.69-10.46µg g-1FW), protocatechuic acid (17.04-4.23µg g-1FW), t-cinnamic acid (22.68-3.93µg g-1FW) and ferulic acid (21.78-3.43µg g-1FW) were abundant in annona fruits while benzoic acid (23.28-4.61µg g-1FW), p-hydroxybenzoic acid (1.79-0.31µg g-1FW), salicylic acid (6.00-2.40µg g-1FW), 3-hydroxybenzoic acid (6.05-0.88µg g-1FW), vanillic acid. (19.13-2.16µg g-1FW), gallic acid (15.88-2.74µg g-1FW), ellagic acid (1.12-0.20µg g-1FW), syringic acid (0.78-0.34µg g-1FW) and sinapic acid (2.16-0.79µg g-1FW) were limited. However, chlorogenic acid was not detected. The results obtained in this study will furnish a better knowledge of the polyphenolic composition in annona fruits.

Targeting CoV-2 Spike RBD: ACE-II complex with phenolic compounds from Cistus (Cistus L.) Bee Pollen for COVID-19 treatment by Molecular Docking Study

Spike glycoprotein on the surface of the SARS-CoV-2 is a class I fusion protein that plays a role in the initial attachment of the virus to the human ACE-II receptor. ACE-II has been implicated in the regulation of heart function and also as a functional receptor for the coronavirus that causes the severe acute respiratory syndrome (SARS). In the present study, a molecular docking study was performed using eleven flavonoids present in Cistus bee pollen against the CoV-2 Spike RBD/ACE-II complex and compared their affinity with the FDA approved drug hydroxychloroquine (HCQ). Binding constants of eleven flavonoids, catechin, pinocembrin, chrysin, caffeic acid phenethyl ester, p-OH Benzoic acid, syringic acid, t-cinnamic acid, p-Coumaric acid, rutin, ferulic acid and gallic acid were measured using the AutoDock 4.2 molecular docking software. Also, these binding constants were then compared to the reference molecule of hydroxychloroquine. According to docking analysis, the results showed us that catechin has the best inhibiton potential among the all analyzed molecules with the high binding energy (-7.77 kcal/mol) and the lowest Ki (2.03 µM) and it is followed by pinocembrin, chrysin, caffeic acid phenethyl ester, respectively. Besides, the reference molecule hydroxychloroquine has binding energy of -7.53 kcal/mol and 3.04 µM. Consequently, high potential of flavonoids in extracts of Cistus bee pollen to interact with CoV-2 Spike RBD/ACE-II complex indicates that this natural product has high potential for Covid-19 treatment, but this needs to be supported by further studies

Comparison of components profile in herbal raw material, extract and pharmaceuticals of Hedera Helix

The aim. To investigate both the profile of components and possible difference among herbal raw materials, semi-products and pharmaceuticals of Hedera helix for determination of main standartisation markers.Materials and methods. Investigation of components profile has been performed using the Shimadzu Nexera X2 chromatographic system coupled with a diode-area detector. The ACE C 18 column (250 mm × 4.6 mm with particle size 5 mm) was used for the separation of components. 0.1 % acetic acid and acetonitrile were used as mobile phase A and B, respectively. Studies have been performed on the leaves, dry extract and capsules of H. helix.Results. The determined profile had no significant variation among samples. It has been presented by 19 various components, such as phenolic acids, flavonoids and triterpene saponins. However, kaempferol, nicotiflorin and t-cinnamic acid were not found in the leaf raw material. Hederacoside C might be highlighted as the main marker of raw materials and products of H. helix due to its significant amount in comparison to other components. Its amount was in the range of 64,80 % up to 71,46 % of the total content of components. Moreover, according to some pharmacological studies, hederacoside C is responsible for pharmaceutical usage of H. helix pharmaceutics. Nevertheless, it is not recommended to standardize the plant-based medicines by one marker, since the pharmaceutical activity of such dosage forms is defined by synergism action of all constituents. Except for hederacoside C significant amounts in comparison to other components were found for chlorogenic acid and 4,5-dicaffeoylquinic acid about 5 % and 3 % respectively. Though the latter was found in small concentrations in leaves (0,058 %). This sample had a much higher amount of 3,5-dicaffeoylquinic acid, but in the case of extract and capsules, its content was lower 1,55 % and 0,66 % respectively. Thus, chlorogenic acid has been chosen as a second marker due to its high concentration in all samples and some pharmaceutical activities, such as antioxidant and anti-inflammatory effects.Conclusions. It was found, that standartisation of H. helix products is preferably to perform with determination both hederacoside C and chlorogenic acid. These components were dominant among all components; besides they possess a wide range of pharmaceutical effects. Hence, quantification of hederacoside C and chlorogenic acid is necessary to ensure the high quality of H. helix pharmaceuticals.

Phenolic profile, antioxidant and enzyme inhibitory activities of underutilized spices from Central Africa.

The aim of the present study is to evaluate phytochemical profile, antioxidant and enzyme inhibitory activity of some underutilized Cameroon spice extracts, viz. The fruit of Xylopia africana, the fruit and the bulb of Aframomum sulcatum; and the bark of Hypodaphnis zenkeri. Four different solvent combinations were used for extraction of phytochemicals. Highest total polyphenol, flavonoid and tannin contents were observed in X. africana extract 10.32 ± 0.49g gallic acid eq/100g of dry matter, 146.66 ± 4.15mg quercetin eq/100g of dry matter, 452.44 ± 2.7mg tannic acid eq/100g spices dry matter. Methanol extracts revealed the presence of chlorogenic acid (0.790-4.312), vanillic acid (0.830-19.768), epicatechin (25.386-34.707), p-coumaric acid (1.127-12.652), protosynapic acid (0.221-186.562) and T-cinnamic acid (3.794-52.58) mg/100g dry spice by HPLC analysis. Extracts of X. africana and H. zenkeri exhibited higher antioxidant activity: DPPH (182.24 ± 2.41mg ascorbic acid eq/g dry spice), ABTS (9.247 ± 0.004g trolox eq/100g spice), hydroxyl free radicals (729.27 ± 3.07mg mannitol eq/100g spice) and reducing power (2.351 ± 0.002g ascorbic acid equivalent/100g spice). Positive and high correlations existed between the antioxidant activity of extracts obtained with different methods and their corresponding phenolic content. Extract of A. sulcatum highly inhibited porcine pancreatic lipase whereas, X. africana and H. zenkeri extracts highly inhibited α-amylase (98.82 and 99.54% respectively). These spices could be utilized as natural antioxidant sources for the management oxidative stress, lipid and carbohydrate metabolism related diseases.

PHENOLIC COMPOSITION AND ANTIOXIDANT PROPERTIES OF ANZER HONEY FROM BLACK SEA REGION OF TURKEY

Anzer honey is produced Turkey's famous Anzer Plateau with rich vegetation in the Eastern Black Sea region.This is the first extensive investigation of the bioactive characteristics of Anzer honey. For this purpose, melissopalinological analysis, total phenolic and flavonoid substances, polyphenolic profile and total antioxidant capacity of honey, ferric reducing antioxidant power test (FRAP) and free radical scavenging capacity of samples were measured by picryhydrazil (DPPH) method. According to the results of the study, the total phenolic content of Anzer honey was 26.92 gallic acid/100g and the total flavonoid substance was 2.79. In the analysis of phenolic compounds of the Anzer honeys, daidzein and syringic acid were not detected. The major phenolic compounds in the honey were, in descending order, pinocembrin, hesperidin, chrysin, protocatechuic acid, p-coumaric acid, catechin, caffeic acid phenyl acid (CAPE), p-OH benzoic acid, caffeic acid, and minor levels of myricetin, luteolin, rutin, resveratrol, epicatechin, t-cinnamic acid, ferulic acid and gallic acid, were also determined. The mean FRAP and DPPH values of the anzer honeys were found to be 110.11 μmolTrolox/100g, and 49.12mg/ml respectively. As a result, although Anzer honeys are not rich in phenolic contents, they are attractive in terms of phenolic compounds.

Role of Salicylic Acid and Components of the Phenylpropanoid Pathway in Basal and Cultivar-Related Resistance of Oilseed Rape (Brassica napus) to Verticillium longisporum.

Enhanced resistance is a key strategy of controlling ‘Verticillium stem striping’ in Brassica napus caused by the soil-borne vascular pathogen Verticillium longisporum. The present study analyses the role of a broad range of components in the phenylpropanoid and salicylic acid (SA) pathways in basal and cultivar-related resistance of B. napus towards V. longisporum. A remarkable increase of susceptibility to V. longisporum in SA-deficient transgenic NahG plants indicated an essential role of SA in basal resistance of B. napus to V. longisporum. Accordingly, elevated SA levels were also found in a resistant and not in a susceptible cultivar during early asymptomatic stages of infection (7 dpi), which was associated with increased expression of PR1 and PR2. In later symptomatic stages (14 or 21 dpi), SA responses did not differ anymore between cultivars varying in resistance. In parallel, starting at 7 dpi, an overall increase in phenylpropanoid syntheses developed in the resistant cultivar, including the activity of some key enzymes, phenylalanine ammonium lyase (PAL), cinnamyl alcohol dehydrogenase (CAD) and peroxidase (POX) and the expression of key genes, PAL4, CCoAMT, CCR, POX. As a consequence, a remarkable increase in the levels of phenolic acids (t-cinnamic acid, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid) occurred associated with cultivar resistance. A principal component analysis including all 27 traits studied indicated that component 1 related to SA synthesis (PR1, PR2, POX, level of free SA) and component 2 related to lignin synthesis (level of free ferulic acid, free p-coumaric acid, conjugated t-cinnamic acid) were the strongest factors to determine cultivar-related resistance. This study provides evidence that both SA and phenolic acid synthesis are important in cultivar-related resistance, however, with differential roles during asymptomatic and symptomatic stages of infection.

On-line HPLC법에 의한 무알코올 머루 발효액의 항산화능 평가

In this study, the chemical composition and antioxidant activities of Moru wine and alcohol-free Moru wine were evaluated. To prepare the alcohol-free analogue, Moru wine was subjected to either atmospheric distillation (NA-AD) or vacuum distillation (80 mbar, 55℃, NA-VD). Among the three different preparations of Moru wines, namely, Moru wine, NA-AD, and NA-VD, the total acidity was the highest in NA-VD, while the soluble solid content was the highest in Moru wine. The total phenolic content, total flavonoid content, and ABTS radical scavenging activity were the highest in NA-AD. The three different preparations of Moru wines were examined by an on-line high-performance liquid chromatography (HPLC)-2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS)-based assay to identify the compounds responsible for the radical scavenging activity of wines. The results obtained for NA-AD and NA-VD in the on-line screening HPLC-ABTS assay were similar. At least 10 different compounds, namely, gallic acid, protocatechuic acid, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, t-ferulic acid, rutin, naringin, and t-cinnamic acid, were identified from Moru wine, NA-AD, and NA-VD. Gallic acid (10.35-24.69 μg/mL) and syringic acid (9.29-43.98 μg /mL) were found to be the major polyphenols in Moru wine, NA-AD, and NA-VD.

Formulation and chemical characterization of Clerodendrum infortunatum leaf extract in relation to anti-fungal activity

The study explored to develop an eco-friendly herbal fungicide from chloroform extract of Clerodendrum infortunatum leaves. The extract upon activity guided purification using flash chromatography yielded eight fractions F3 through F10. Total phenol and flavonoid contents in the fractions ranged from 0.12-48.25 mg GAE/g and 0.03–25.29 mg QE/g. LC-MS/MS analysis confirmed the identification of seven phenolic acids across different fractions, the total of which varied between 0 and 2.17 mg/g. Emulsifiable Concentrate (20%) formulation was made with the extract and fractions and tested against Phomopsis vexans causing fruit rot disease in brinjal. Of the various fractions, F8 displayed highest antifungal activity (ED50 = 46.8 μg/ml). Antifungal activity of leaf extract/fractions was correlated with total phenol, total flavonoid and total phenolic acids (r = -0.60 to -0.69). Among the phenolic acids, benzoic acid showed maximum antifungal activity followed by t-cinnamic acid. The relationship between phenolic composition and activity is also reported.

Phenolic compounds characterization and antioxidant activities of selected spices from Cameroon

Methanol extracts of five spices from Cameroon were analyzed for their phytochemical composition and antioxidant activities. The Xylopia aethiopica extract with the highest total phenolics and flavonoids contents showed a strongest antioxidant activity compared to tert-butylhydroquinone (TBHQ) using both the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt (ABTS) radicals scavenging assay. The identification and quantification of major phenolics acids and flavonoids was carried out by HPLC-DAD. T-cinnamic acid and ferulic acid was the phenolic acids mainly distributed within the methanolic extracts analyzed. Sinapic acid was identified at low concentration only in Ricinodendron heudelotii. The common flavonoids catechin and epicatechin were detected with highest concentration in Xylopia aethiopica extract. Eugenol was identified at high concentration (125.39–1326.29 μg/g) in all extracts. The results of the present study suggest that the extracts analyzed, particularly Xylopia aethiopica and Aframomum citratum are potential sources of natural antioxidants agents.

Unravelling the potential of the medicinal halophyte Eryngium maritimum L.: In vitro inhibition of diabetes-related enzymes, antioxidant potential, polyphenolic profile and mineral composition

This work searched for the biotechnological potential and chemical characterisation of the medicinal halophyte Eryngium maritimum L. as source of bioactive natural products with enzymatic inhibitory properties and antioxidant capacity. With that aim, herbal formulations traditionally used in folk medicine, namely tisanes (infusions and decoctions) and tinctures, were prepared from four different anatomical organs (roots, stems, leaves and flowers) and assessed for in vitro inhibition of enzymes related with diabetes and for antioxidant potential. Phenolic fingerprinting and mineral contents were also assessed. Sea holly's tisanes, particularly from flowers and leaves, had the highest phenolic content although tinctures were comparatively richer considering the ingestion dosage. The main constituents identified were carvacrol, 2,3-dimethoxybenzoic acid, naringenin, catechin and t-cinnamic acid; from the several compounds identified, naringin, naringenin and 2,3-dimethoxybenzoic acid are here firstly described in the genus and epicatechin and carvacrol in the species. In all extracts, sodium was the most abundant mineral, followed by potassium, calcium and magnesium, pointing to possible nutritional applications of these beverages/tinctures as macronutrients supplementary source. Sea holly's tinctures (stems, leaves and flowers) were capable of inhibiting dietary carbohydrate digestive enzymes (α-glucosidase and α-amylase) and had in vitro antioxidant potential, particularly flowers. Altogether, results highlight that sea holly extracts, especially tinctures from stems, leaves and flowers, could be a novel source of α-glucosidase and α-amylase inhibitors, antioxidant compounds and also phenolic and mineral constituents, thus suggesting they may be interesting to further explore as potential health-promoting herbal beverages, food additives or other products.

Evaluating water deficit and glyphosate treatment on the accumulation of phenolic compounds and photosynthesis rate in transgenic Codonopsis lanceolata (Siebold & Zucc.) Trautv. over-expressing γ-tocopherol methyltransferase (γ-tmt) gene.

The effect of water stress and herbicide treatment on the phenolic compound concentration and photosynthesis rate in transgenic Codonopsis lanceolata plants over-expressing the γ-tmt gene was investigated and compared to that in control non-transgenic C. lanceolata plants. The total phenolic compound content was investigated using high-performance liquid chromatography combined with diode array detection in C. lanceolata seedlings 3 weeks after water stress and treatment with glyphosate. Changes in the composition of phenolic compounds were observed in leaf and root extracts from transformed C. lanceolata plants following water stress and treatment with glyphosate. The total concentration of phenolic compounds in the leaf extracts of transgenic samples after water stress ranged from 3455.13±40.48 to 8695.00±45.44µgg-1 dry weight (DW), whereas the total concentration phenolic compound in the leaf extracts of non-transgenic control samples was 5630.83±45.91µgg-1DW. The predominant phenolic compounds that increased after the water stress in the transgenic leaf were (+) catechin, benzoic acid, chlorogenic acid, ferulic acid, gallic acid, rutin, vanillic acid, and veratric acid. The total concentration of phenolic compounds in the leaf extracts of transgenic samples after glyphosate treatment ranged from 4744.37±81.81 to 12,051.02±75.00µgg-1 DW, whereas the total concentration of the leaf extracts of non-transgenic control samples after glyphosate treatment was 3778.28±59.73µgg-1 DW. Major phenolic compounds that increased in the transgenic C. lanceolata plants after glyphosate treatment included kaempherol, gallic acid, myricetin, p-hydroxybenzjoic acid, quercetin, salicylic acid, t-cinnamic acid, catechin, benzoicacid, ferulic acid, protocatechuic acid, veratric acid, and vanillic acid. Among these, vanillic acid showed the greatest increase in both leaf and root extracts from transgenic plants relative to those from control C. lanceolata plants following treatment with glyphosate, which could affect the 5-enol-pyruvyl shikimate-3-phosphate (EPSP) synthase, an enzyme in the shikimate pathway. We observed enhanced stomatal conductance (gs) and photosynthesis rate (A) in the transgenic plants treated with water stress and glyphosate treatment. The results of this study demonstrated large variations in the functioning of secondary metabolites pathway in response glyphosate and water stress in transgenic C. lanceolata.

Reduction of L-phenylalanine in protein hydrolysates using L-phenylalanine ammonia-lyase from Rhodosporidium toruloides.

L-Phenylalanine ammonia-lyase (PAL, EC 4.3.1.25) from Rhodosporidium toruloides was utilized to remove L-phenylalanine (L-Phe) from different commercial protein hydrolysates. A casein acid hydrolysate (CAH, L-Phe ~2.28 %) was employed as a model substrate. t-Cinnamic acid resulting from deamination of L-Phe was extracted, analyzed at λ = 290 nm, and used for PAL activity determination. Optimum reaction conditions, optimized using successive Doehlert design, were 35 mg mL(-1) of CAH and 800 mU mL(-1) of PAL, while temperature and pH were 42 °C and 8.7, respectively. Reaction kinetics of PAL with CAH was determined under optimized conditions. Then, removal of L-Phe from CAH was tested. Results showed that more than 92 % of initial L-Phe was eliminated. Similar results were obtained with other protein hydrolysates. These findings demonstrate that PAL is a useful biocatalyst for L-Phe removal from protein hydrolysates, which can be evaluated as potential ingredients in foodstuffs for PKU patients.

Potential use of microwave treatment on fresh-cut carrots: physical, chemical and microbiological aspects.

The effect of microwave treatments (900 and 750 W for 45 and 60 s) on the microbial, physicochemical and sensory properties of fresh-cut carrot slices and the contents of several bioactive compounds was studied. Carrot samples were stored for 7 days at 5 °C. The microwaving of fresh-cut carrots reduced the initial respiration rate (8.6 CO2 mL kg(-1) h(-1)) by 55-74% compared with untreated samples, although the rates then increased during storage. The initial pH (6.7), titratable acidity (0.036%), soluble solid content (8.2 °Brix) and shelf-life of the samples did not differ greatly from those of the untreated samples. Microwaving prevented the incipient whitening and surface dryness during storage. In general, no significant changes in phenylalanine ammonia lyase activity (5.5 µmol t-cinnamic acid kg(-1) h(-1)), total phenolics (TP, 81.3 mg chlorogenic acid equivalent kg(-1) fresh weight (FW)) or total antioxidant capacity (TAC, 74.2 µmol Trolox equivalent kg(-1) FW) were observed on the processing day or over storage. However, the mildest treatment (750 W for 45 s) caused TP and TAC enhancements of 118 and 394% respectively after 7 days of shelf-life. Microwave treatments reduced the initial microbial loads of the samples by up to 1.8 log units, although their microbial growth was greater than that of the untreated samples throughout storage. Mild microwave treatments such as 750 W/45 s and 750 W/60 s are a good sustainable alternative to the use of NaOCl; however, combining them with other sanitizing techniques is needed to control microbial growth throughout the shelf-life of fresh-cut carrot slices.

Morphological and physiological effects of trans-cinnamic acid and its hydroxylated derivatives on maize root types

Roots encounter cinnamic acid and its hydroxylated derivatives that are commonly found in soils. However, root systems consist of different root types with different morphological and physiological characteristics. Very little is known about the responses and adaptation mechanisms of the root types to cinnamic acid and its hydroxylated derivatives. In this study, the morphological and physiological responses of different maize root types exposed to different concentrations of t-cinnamic, ferulic, caffeic or p-coumaric acids were investigated. The results showed that the effects of allelochemicals were dependent on concentration, chemical structure, root type and process considered. In particular, t-cinnamic acid was characterized by higher allelopathic activity when compared with its derivatives, where a hydroxyl or methyl groups were present in aromatic ring. Among root types it was possible to delineate the following tolerance hierarchy: primary > seminal > nodal > lateral of the primary = lateral of the seminal roots. Moreover, primary and seminal roots showed a different strategy to cope the chemical stress by either increasing or decreasing specific root length. Finally, an electrophysiological approach identified an involvement of proton pump activity and consequently a decrease in nitrate uptake.

Evaluating the potential of immobilized bacterial consortium for black liquor biodegradation.

Two indigenous bacterial strains, Bacillus megaterium ETLB-1 (accession no. KC767548) and Pseudomonas plecoglossicida ETLB-3 (accession no. KC767547), isolated from soil contaminated with paper mill effluent, were co-immobilized on corncob cubes to investigate their biodegradation potential against black liquor (BL). Results exhibit conspicuous reduction in color and lignin of BL upto 913.46 Co-Pt and 531.45 mg l(-1), respectively. Reduction in chlorophenols up to 12 mg l(-1) was recorded with highest release of chloride ions, i.e., 1290 mg l(-1). Maximum enzyme activity for lignin peroxidase (LiP), manganese peroxidase (MnP), and laccase (LAC) was recorded as 5.06, 8.13, and 8.23 U ml(-1), respectively, during the treatment. Scanning electron microscopy (SEM) revealed successful immobilization of bacterial strains in porous structures of biomaterial. Gas chromatography/mass spectroscopy (GC/MS) showed formation of certain low molecular weight metabolites such as 4-hydroxy-benzoic acid, 3-hydroxy-4-methoxybenzaldehyde, ferulic acid, and t-cinnamic acid and removal of majority of the compounds (such as teratogenic phthalate derivatives) during the period of treatment. Results demonstrated that the indigenous bacterial consortium possesses excellent decolorization and lignin degradation capability which enables its commercial utilization in effluents treatment system.

Investigating the in-vitro bioaccessibility of propolis and pollen using a simulated gastrointestinal digestion System

SummaryNowadays, there is a growing interest in the physiological benefits of natural antioxidants in foods. Honey bee products, especially propolis and pollen, have strong antioxidative activity and beneficial effects in human body. The aim of this study was to determine the total phenolic and total flavonoid contents and antioxidant activities of propolis and pollen, as well as bioaccessibility of these products by an in-vttro model simulating gastrointestinal digestion. Total phenolic content, total flavonoid content and antioxidant activity analysis were applied to all samples as well as samples collected after the application of in-vitro gastrointestinal method. Phenolic profiles of propolis and pollen samples were also identified by HPLC-PDA. Results indicated that total phenolic contents of IN fractions (bioaccessible fraction) of propolis and pollen was 2.0 and 2.1 mg GAE/g; total flavonoid content was 0.9 and 0.2 mg QE/g; total antioxidant activity was 19.6 and 0.6 mg TE/g, respectively. Percentages of the IN fraction of propolis and pollen were 1% and 9% for total phenolic content; 0.2% and 1% for total flavonoid content; 4% and 3% for total antioxidant activity. Phenolic compounds including caffeic acid, p-coumaric acid, ferrulic acid, quercetin, pinobanksin, apigenin, t-cinnamic acid, luteolin, pinocembrin, chrysin, galangin, kaempferol and pinostrobin were detected in propolis, and 2-hydroxycinnamic acid, quercetin-3-glucoside, quercetin, myricetin, luteolin, quercetin-3-galactoside, kaempferol, and galangin were detected in pollen samples.

In vitro Anti‐diabetic Activity and Chemical Characterization of an Apolar Fraction of Morus alba Leaf Water Extract

The tea from the white mulberry (Morus alba L.) leaf is a worldwide known traditional medicine of type II diabetes. Here, we report the investigation of the dichloromethane-soluble fraction obtained in a 0.24% m/m yield from the hot water extract of mulberry leaves. A significant, dose-dependent activity was found by means of the 24-h glucose consumption of fully differentiated adipocytes both in the absence and presence of insulin. The fraction was characterized by HPLC-DAD, GC-MS and GC-FID. The main constituent (40.3% by means of GC-FID) was isolated and identified as loliolide by EIMS, HRESIMS and NMR spectroscopy. In the active fraction benzyl alcohol, ethyl benzoate, t-cinnamic acid, p-hydroxyacetophenone, t-coniferyl alcohol and synapil alcohol were also identified by GC-MS and quantified by GC-FID (0.7, 1.3, 1.5, 2.9, 7.5 and 2.6%, respectively).

A peroxisomally localized acyl-activating enzyme is required for volatile benzenoid formation in a Petunia×hybrida cv. ‘Mitchell Diploid’ flower

Floral volatile benzenoid/phenylpropanoid (FVBP) biosynthesis is a complex and coordinate cellular process executed by petal limb cells of a Petunia×hybrida cv. ‘Mitchell Diploid’ (MD) plant. In MD flowers, the majority of benzenoid volatile compounds are derived from a core phenylpropanoid pathway intermediate by a coenzyme A (CoA) dependent, β-oxidative scheme. Metabolic flux analysis, reverse genetics, and biochemical characterizations of key enzymes in this pathway have supported this putative concept. However, the theoretical first enzymatic reaction, which leads to the production of cinnamoyl-CoA, has only been physically demonstrated in a select number of bacteria like Streptomyces maritimus through mutagenesis and recombinant protein production. A transcript hasbeen cloned and characterized from MD flowers that shares high homology with an Arabidopsis thaliana transcript ACYL-ACTIVATING ENZYME11 (AtAAE11) and the S. maritimus ACYL-COA:LIGASE (SmEncH). In MD, the PhAAE transcript accumulates in a very similar manner as bona fide FVBP network genes, i.e. high levels in an open flower petal and ethylene regulated. In planta, PhAAE is localized to the peroxisome. Upon reduction of PhAAE transcript through a stable RNAi approach, transgenic flowers emitted a reduced level of all benzenoid volatile compounds. Together, the data suggest that PhAAE may be responsible for the activation of t-cinnamic acid, which would be required for floral volatile benzenoid production in MD.

A liquid chromatographictandem mass spectrometric method for the quantitation of eight components involved in lithospermic acid B biosynthesis pathway in Salvia miltiorrhiza hairy root cultures

Elucidation of regulatory mechanisms of plant secondary metabolism requires quantitation of metabolic fluxes. A method of high-performance liquid chromatography–tandem mass spectrometry (LC-MS/MS) has been developed for the trace analysis of eight components (rosmarinic acid, lithospermic acid B, L-phenylalanine, t-cinnamic acid,4-coumaric acid, L-tyrosine, 4-hydroxyphenylpyruvic acid and homogentisic acid) involved in lithospermic acid B biosynthesis pathway in Salvia miltiorrhiza hairy root cultures. The separation was performed by a ZORBAX SB-C18 column (3.5 µm, 2.1 x 150 mm, I.D. Agilent Corporation, MA, USA) and a C18 guard column (5 µm, 4.0 x 2.0 mm, Agilent Corporation, MA, USA) with an isocratic mobile phase consisting of acetonitrile-water (55:45, v/v) at a flow rate of 0.3 ml/min. The components were detected by an Agilent G6410A triple quadrupole LC/MS system equipped with a MassHunter interface. The components were detected using electrospray ionization (ESI) in negative-ion mode and quantified by multiple-reaction monitoring (MRM) mode using the transition mass of m/z 359→161, 717→519, 164→147, 147→103, 163→119, 180→119, 179→107 and 167→123 for rosmarinic acid, lithospermic acid B, L-phenylalanine, t-cinnamic acid, 4-coumaric acid, L-tyrosine, 4-hydroxyphenylpyruvic acid and homogentisic acid, respectively. The recovery of the method was in the range of 95.4 to 105.5%, and all the components showed good linearity (ri¼ž0.995) in a relatively wide concentration range. This method has been successfully applied to the determination of the eight components in different elicitor (Methyl jasmonate and silver ions) treated S. miltiorrhiza hairy root cultures, for describing elicitor-based regulatory effect to lithospermic acid B metabolic fluxes. Key words: Salvia miltiorrhiza, biosynthesis pathway, liquid chromatography–tandem mass spectrometry, phenolic acids.