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https://www.readbyqxmd.com/read/29346322/regioselective-synthesis-of-procyanidin-b6-a-4-6-condensed-catechin-dimer-by-intramolecular-condensation
#1
Yusuke Higashino, Taisuke Okamoto, Kazuki Mori, Takashi Kawasaki, Masahiro Hamada, Noriyuki Nakajima, Akiko Saito
Proanthocyanidins, also known as condensed tannins or oligomeric flavonoids, are found in many edible plants and exhibit interesting biological activities. Herein, we report a new, simple method for the stereoselective synthesis of procyanidin B6, a (+)-catechin-(4-6)-(+)-catechin dimer, by Lewis acid-catalyzed intramolecular condensation. The 5-O-t-butyldimethylsilyl (TBDMS) group of 5,7,3'4'-tetra-O-TBDMS-(+)-catechin was regioselectively removed using trifluoroacetic acid, leading to the "regio-controlled" synthesis of procyanidin B6...
January 18, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29345975/nano-and-micro-particles-for-delivery-of-catechins-physical-and-biological-performance
#2
Jian-Hui Ye, Mary Ann Augustin
Catechins, present in many fruits and vegetables, have many health benefits, but they are prone to degradation. Nano- and micro-particle systems have been used to stabilise catechins when exposed to adverse environments and to improve their bioavailability after ingestion. This review discusses the inherent properties of various catechins, the design of delivery formulations and the properties of catechin-loaded nano- and micro-particles. The protection afforded to catechins during exposure to harsh environmental conditions and gastrointestinal tract transit is reviewed...
January 18, 2018: Critical Reviews in Food Science and Nutrition
https://www.readbyqxmd.com/read/29345909/a-metabolomics-study-reveals-enhanced-inhibition-and-metabolic-dysregulation-in-e-coli-induced-by-lactobacillus-acidophilus-fermented-black-tea-extract
#3
Kundi Yang, Mattew Duley, Jiangjiang Zhu
This study examined the ability of Lactobacillus acidophilus (LA) to ferment black tea extract (BTE), and the enhancement of Escherichia coli cellular uptake of phenolic compounds when this bacteria was incubated with fermented BTE. The inhibitory effects of BTE to E. coli bacteria, with and w/o fermentation, were compared. Several intracellular phenolic compounds, as well as metabolic profiles of E. coli with and w/o treatments, were also determined using a HPLC-MS/MS-based approach. Our results showed that out of three concentrations from the non-fermented BTE treatment, only the extract from the 25 mg/ml tea leaves solution could inhibit E...
January 18, 2018: Journal of Agricultural and Food Chemistry
https://www.readbyqxmd.com/read/29345213/matcha-green-tea-drinks-enhance-fat-oxidation-during-brisk-walking-in-females
#4
Mark Elisabeth Theodorus Willems, Mehmet Akif Şahin, Matthew David Cook
Intake of the catechin epigallocatechin gallate and caffeine has been shown to enhance exercise-induced fat oxidation. Matcha green tea powder contains catechins and caffeine and is consumed as a drink. We examined the effect of Matcha green tea drinks on metabolic, physiological and perceived intensity responses during brisk walking. Thirteen females (age: 27±8 yr, body mass: 65±7 kg, height: 166±6 cm) volunteered. Resting metabolic equivalent (1-MET) was measured using Douglas bags (1-MET: 3.4±0.3 ml·kg-1·min-1)...
January 18, 2018: International Journal of Sport Nutrition and Exercise Metabolism
https://www.readbyqxmd.com/read/29343778/fumarate-based-metal-organic-frameworks-as-a-new-platform-for-highly-selective-removal-of-fluoride-from-brick-tea
#5
Fei Ke, Chuanyi Peng, Tian Zhang, Mengran Zhang, Chengyan Zhou, Huimei Cai, Junfa Zhu, Xiaochun Wan
Adsorption and removal of fluoride from brick tea is very important but challenging. In this work, two fumarate-based metal-organic frameworks (MOFs) were synthesized for the selective removal of fluoride from brick tea infusion. MOFs were examined for adsorption time, effect of dose, and uptake capacity at different initial concentrations and temperatures. Remarkably, over 80% fluoride removal was achieved by MOF-801 within 5 min at room temperature, while no significant adsorption occurred for the catechins and caffeine in the brick tea infusion...
January 17, 2018: Scientific Reports
https://www.readbyqxmd.com/read/29342884/effect-of-the-extraction-process-on-the-biological-activity-of-lyophilized-apricot-extracts-recovered-from-apricot-pomace
#6
Dina Cheaib, Nada El Darra, Hiba N Rajha, Iman El-Ghazzawi, Richard G Maroun, Nicolas Louka
The preservation of polyphenols in fruits by lyophilization has gained great interest in the recent decades. The present study aims to assess the impact of the pre-treatment extraction methods heat-assisted extraction (HAE) and infrared (IR) on lyophilized apricot pomace extracts. Then to test the conservation of polyphenols quantities as well as their bioactivities (antiradical and antibacterial) in lyophilized extract. An aqueous extract was obtained through either heat-assisted extraction or infrared pre-treatments then lyophilized to obtain a dried form...
January 14, 2018: Antioxidants (Basel, Switzerland)
https://www.readbyqxmd.com/read/29341798/phenolic-constituents-and-inhibitory-effects-of-hibiscus-sabdariffa-l-sorrel-calyx-on-cholinergic-monoaminergic-and-purinergic-enzyme-activities
#7
Ganiyu Oboh, Taiwo M Adewuni, Adedayo O Ademiluyi, Tosin A Olasehinde, Ayokunle O Ademosun
This study revealed the effect of phenolic extract from Hibiscus sabdariffa L. (sorrel) calyx on acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase (MAO), and ecto-5' nucleotidase (E-NTDase) activities as well as pro-oxidant-induced oxidative damage in rat brain in vitro. Sorrel extract inhibited AChE (EC50 = 46.96 µg/mL), BChE (EC50 = 40.38 µg/mL), MAO (EC50 = 43.69 µg/mL), and E-NTDase (EC50 = 40.52 µg/mL) and stimulated Na+/K+-ATPase (EC50 = 22.01 µg/mL) activities. The phenolic extract also reduced Fe2+- (EC50 = 22...
January 17, 2018: Journal of Dietary Supplements
https://www.readbyqxmd.com/read/29339972/evaluation-of-green-tea-extract-as-a-safe-personal-hygiene-against-viral-infections
#8
Yun Ha Lee, Yo Han Jang, Young-Seok Kim, Jinku Kim, Baik Lin Seong
Background: Viral infections often pose tremendous public health concerns as well as economic burdens. Despite the availability of vaccines or antiviral drugs, personal hygiene is considered as effective means as the first-hand measure against viral infections. The green tea catechins, in particular, epigallocatechin-3-gallate (EGCG), are known to exert potent antiviral activity. In this study, we evaluated the green tea extract as a safe personal hygiene against viral infections. Results: Using the influenza virus A/Puerto Rico/8/34 (H1N1) as a model, we examined the duration of the viral inactivating activity of green tea extract (GTE) under prolonged storage at various temperature conditions...
2018: Journal of Biological Engineering
https://www.readbyqxmd.com/read/29337873/two-novel-proline-containing-catechin-glucoside-from-water-soluble-extract-of-codonopsis-pilosula
#9
Fu-Ying Qin, Li-Zhi Cheng, Yong-Ming Yan, Bao-Hua Liu, Yong-Xian Cheng
Choushenflavonoids A (1) and B (2), two unusual proline-containing catechin glucosides, were isolated from the roots of Codonopsis pilosula cultivated in a high-altitude location of Yunnan province. Their structures were determined by spectroscopic data and chemical methods. Specifically, the absolute configuration of glucose residue in 1 and 2 was assigned by acid hydrolysis followed by derivatization and gas chromatography (GC) analysis. In addition, biological evaluation of 1 and 2 against Sirtuin 1 (SIRT1) was carried out...
January 16, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/29337349/phytochemicals-anti-inflammatory-antiproliferative-and-methylglyoxal-trapping-properties-of-zijuan-tea
#10
Xiong Gao, Chi-Tang Ho, Xiaofei Li, Xiaorong Lin, Yuanyuan Zhang, Zhongzheng Chen, Bin Li
Zijuan tea (Camellia sinensis var. assamica) is a unique anthocyanin-rich tea cultivar in China. Although chemical component analysis of Zijuan tea and extraction technology of anthocyanins was widely documented, its functional properties have not been extensively explored. In this study, the anti-inflammatory, antiproliferative, and methylglyoxal (MGO) trapping activities of water extract (ZWE) and ethyl acetate extract (ZEE) of Zijuan tea were investigated for the 1st time. Results showed that ZWE and ZEE exhibited inhibitory effects on nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-6 production as well as inducible nitric oxide synthase protein (iNOS) expression in lipopolysaccharide (LPS)-induced RAW 264...
January 16, 2018: Journal of Food Science
https://www.readbyqxmd.com/read/29334662/aqueous-extracts-of-two-tropical-ethnobotanicals-tetrapleura-tetraptera-and-quassia-undulata-improved-spatial-and-non-spatial-working-memories-in-scopolamine-induced-amnesic-rats-influence-of-neuronal-cholinergic-and-antioxidant-systems
#11
Veronica O Odubanjo, Emmanuel O Ibukun, Ganiyu Oboh, Stephen A Adefegha
BACKGROUND: Tetrapleura tetraptera (TT) and Quassia undulata (QU) are two predominant tropical ethnobotanicals with various medicinal values but are commonly used in folklore for the treatment of mental illness without justifiable mechanisms of action. AIM OF THE STUDY: To investigate the effects of aqueous extracts from TT fruits and QU leaves on the spatial and non-spatial working memory, antioxidant status and activities of neuronal marker enzymes of scopolamine-induced amnesic rats and thus, understand the possible mechanism of action of these plants...
January 11, 2018: Biomedicine & Pharmacotherapy, Biomédecine & Pharmacothérapie
https://www.readbyqxmd.com/read/29334323/development-of-functional-agricultural-products-utilizing-the-new-health-claim-labeling-system-in-japan
#12
Mari Maeda-Yamamoto, Toshio Ohtani
In April 2015, Consumer Affairs Agency of Japan launched a new food labeling system known as "Foods with Function Claims (FFC)." Under this system, the food industry independently evaluates scientific evidence on foods and describes their functional properties. As of May 23, 2017, 1023 FFC containing 8 fresh foods have been launched. Meanwhile, to clarify the health-promoting effects of agricultural products, National Agriculture and Food Research Organization (NARO) implemented the "Research Project on Development of Agricultural Products" and demonstrated the risk reduction of osteoporosis of β-cryptoxanthin rich Satsuma mandarins and the anti-allergic effect of the O-methylated catechin rich tea cultivar Benifuuki...
January 15, 2018: Bioscience, Biotechnology, and Biochemistry
https://www.readbyqxmd.com/read/29333387/physicochemical-and-antioxidant-properties-of-honeys-from-the-sundarbans-mangrove-forest-of-bangladesh
#13
M Rabiul Islam, Tahmina Pervin, Hemayet Hossain, Badhan Saha, Sheikh Julfikar Hossain
This study evaluated the physicochemical, nutritional, antioxidant, and phenolic properties of ten honey samples from the Sundarbans mangrove forest, Bangladesh. The average pH, electrical conductivity, total dissolved solid, ash, moisture, hydroxymethyl furfural, titrable acidity, and absorbance were 4.3, 0.38 mS/cm, 187.5 ppm, 0.14%, 17.88%, 4.4 mg/kg, 37.7 meq/kg, and 483 mAU, respectively. In the honeys, the average contents of Ca, Cu, Fe, K, Mg, Mn, and Na were 95.5, 0.19, 6.4, 302, 39.9, 3.4, and 597 ppm, respectively, whereas Cd, Cr, Pb, and Ni were not found...
December 2017: Preventive Nutrition and Food Science
https://www.readbyqxmd.com/read/29332714/oral-green-tea-catechins-do-not-provide-photoprotection-from-direct-dna-damage-induced-by-higher-dose-solar-simulated-radiation-a-randomized-controlled-trial
#14
Mark D Farrar, Raqib Huq, Sarah Mason, Anna Nicolaou, Kayleigh A Clarke, Tristan P Dew, Gary Williamson, Rachel E B Watson, Lesley E Rhodes
No abstract text is available yet for this article.
February 2018: Journal of the American Academy of Dermatology
https://www.readbyqxmd.com/read/29331860/c18-core-shell-column-with-in-series-absorbance-and-fluorescence-detection-for-simultaneous-monitoring-of-changes-in-stilbenoid-and-proanthocyanidin-concentrations-during-grape-cane-storage
#15
Vania Sáez, Camila Gayoso, Sebastián Riquelme, Julie Pérez, Carola Vergara, Claudia Mardones, Dietrich von Baer
Grape canes, the residues from the annual pruning of vines, contain high levels of inducible (E)-resveratrol and also oligomeric stilbenoids and proanthocyanidins. These two families of phenolic compounds are bioactive, but to quantify them in a single chromatographic run using only ultraviolet detection is a difficult task. To overcome this limitation, a chromatographic method was developed using a core shell column for separation, an ultraviolet-visible diode array detector (DAD) and a fluorescence (FL) detector connected in series for quantification, with an electrospray ionization interface (ESI) and a triple quadrupole mass spectrometric detector (MS/MS) added for identification of the analytes...
December 29, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
https://www.readbyqxmd.com/read/29330916/separation-of-three-polar-compounds-from-rheum-tanguticum-by-high-speed-counter-current-chromatography-with-an-ethyl-acetate-glacial-acetic-acid-water-system
#16
Tao Chen, Ping Wang, Nana Wang, Chongyang Sun, Xue Yang, Hongmei Li, Guoying Zhou, Yulin Li
The separation of polar compounds by high-speed counter-current chromatography is still regarded as a challenge. In this study, an efficient strategy for the separation of three polar compounds from Rheum tanguticum has been successfully conducted by using high-speed counter-current chromatography. X-5 macroporous resin chromatography was used for the fast enrichment of the target compounds. Then, the target fraction was directly introduced into high-speed counter-current chromatography for separation using ethyl acetate/glacial acetic acid/water (100:1:100, v/v) as the solvent system...
January 13, 2018: Journal of Separation Science
https://www.readbyqxmd.com/read/29329871/isolation-of-proanthocyanidins-from-red-wine-and-their-inhibitory-effects-on-melanin-synthesis-in-vitro
#17
Takahiro Fujimaki, Shoko Mori, Manabu Horikawa, Yuko Fukui
The red wines made from Vitis vinifera were identified as skin-whitening effectors by using in vitro assays. OPCs in the wine were evaluated for tyrosinase activity and melanogenesis. Strong tyrosinase inhibitory activity was observed in fractions with high oligomeric proanthocyanidin (OPC) content. Among OPC dimers, a strong inhibitory effect on tyrosinase was observed with OPCs which contain (+)-catechin as an upper unit. Melanogenesis inhibitory effect was observed with OPCs which have (-)-epicatechin as upper units...
May 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29329862/active-compounds-antioxidant-activity-and-%C3%AE-glucosidase-inhibitory-activity-of-different-varieties-of-chaenomeles-fruits
#18
Jing Miao, Xia Li, Chengcheng Zhao, Xiaoxiao Gao, Ying Wang, Wenyuan Gao
Chaenomeles is an important source for food industry in China, and its planting area is expanding year by year. This study was conducted to evaluate different varieties of Chaenomeles by comparing the chemical compositions, antioxidant activity and α-glucosidase inhibitory activity of peels and fleshes from twelve varieties of Chaenomeles. In the results, peels of Chaenomeles contain more phenolics, flavonoids and triterpenes, and show better antioxidant activity and α-glucosidase inhibitory activity than their fleshes...
May 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29329833/effect-of-brewing-time-and-temperature-on-antioxidant-capacity-and-phenols-of-white-tea-relationship-with-sensory-properties
#19
S Pérez-Burillo, R Giménez, J A Rufián-Henares, S Pastoriza
White tea is highly consumed due to its sensory properties and health benefits, although most scientific reports don't include the analysis of both properties. Therefore, the objective of the present study was to unravel the best brewing conditions for optimal extraction of the bioactive compounds and antioxidant capacity, while realising the best sensory properties. Infusions of eighty commercial teas (sold in bags or leaves) were obtained at different time-temperature ratios, studying bioactive compounds (caffeine and individual catechins), antioxidant capacity and sensory analysis...
May 15, 2018: Food Chemistry
https://www.readbyqxmd.com/read/29329610/bacopa-monnieri-extracts-prevent-hydrogen-peroxide-induced-oxidative-damage-in-a-cellular-model-of-neuroblastoma-imr32-cells
#20
Gaurav Bhatia, Vikram Dhuna, Kshitija Dhuna, Manpreet Kaur, Jatinder Singh
Neurodegenerative diseases are the consequences of imbalance between the production of oxidative stress and its nullification by cellular defense mechanisms. Hydrogen peroxide (H2O2), a precursor of deleterious reactive oxygen species, elicits oxidative stress, resulting in severe brain injuries. Bacopa monnieri is well known for its nerve relaxing and memory enhancing properties. The present study was designed to evaluate the protective effects of extracts from Bacopa monnieri against H2O2 induced oxidative stress using a cellular model, neuroblastoma IMR32 cell line...
November 2017: Chinese Journal of Natural Medicines
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