Papers by Keyword: Flavonoids

Abstract: Black galingale is a medicinal plant that has medicinal properties. The major constituents found in black galingale rhizomes are flavonoids, which display antioxidant activities. Therefore, in this research, the focus is to isolate and structurally determine bioactive compounds from the ethyl acetate extract of black galingale rhizomes and evaluate their antioxidant and antimicrobial activity, The black galingale rhizomes were extracted by maceration using ethyl acetate as a solvent. the compounds were isolated by column chromatography using hexane: ethyl acetate as an eluent solvent system. The isolated compounds were examined and characterized using FT-IR, UV-Vis, and NMR techniques, examined antioxidant activity by DPPH assay, and antimicrobial activity. From the extraction of ethyl acetate extract, it was found that 4 pure flavonoid compounds could be extracted. The FT-IR spectral data of 4 compounds showed a unique vibration corresponding to OH stretching, CH stretching, C=O stretching, C=C stretching of an aromatic ring, and C-O-C bond. Antioxidant activity testing by DPPH assay found 5-hydroxy-3,7-dimethoxyflavone (1) to have the highest antioxidant activity at 73.79% compared to the standard Trolox with 133.37±1.60 mM. Antimicrobial activity testing found that 3,5,7-trimethoxyflavone (3) showed the best growth inhibition activities against B. megaterium and S. aureus, Moreover, it studies the nanoemulsion properties of 5-hydroxy-3,7-dimethoxyflavone (1) was found stable with a nanoparticle size of 21.1 nm, a zeta potential of-49.7 mV, and has PDI of 0.227. Therefore, this research shows that the extract from black galingale rhizome could be used as an active ingredient in the cosmetics industry.

Abstract: The main aim of this paper is to present experimental results concerning the effects of the temperature and velocity of drying air on the flavonoids extraction rate of houttuynia cordata thunb by heat pump dryer under real weather conditions at Ho Chi Minh City, Vietnam. Drying experiments were carried out at the drying air temperature of 35, 40, 45 and 50 °C, and drying air velocity of 1.0, 1.5, 2.0 and 2.5 m/s, respectively. The experimental results showed that the highest amount of flavonoid extraction rate of the houttuynia cordata thunb was 87.525 mg/g corresponding to the drying air temperature of 45 °C and drying air velocity of 2.0 m/s. The aim also involves analyzing the effects of the drying temperature and drying velocity on the drying time, moisture content, and the specific moisture extraction rate (SMER).

Abstract: Indonesia has great benefits as a tropical country where a wide variety of fruits, vegetables and other plants are found so that they have the potential to be a source of bioactive compounds such as flavonoid compounds. This research will study the effect of solvent polarity on the extraction of flavonoid bioactive compounds in bitter melon (Momordica Charantia L.) fruit and leaves using the Soxhlet method. The solvents used were non-polar (n-hexane), polar (ethanol), and semi-polar (ethyl acetate) with a concentration of 50% (v/v). Extraction was carried out at the boiling point of the solvent at various extraction times of 60, 90, 120, and 150 minutes with a sample to solvent ratio of 1:20 (w/w). From this research, it was known that ethyl acetate was able to extract bitter melon with the highest yield than n-hexane and ethanol, which was 36% at 90 minutes. The largest total flavonoid compound (TFC) was obtained in extraction using ethanol then n-hexane and ethyl acetate. In Soxhlet extraction, the semi-polar solvent (ethyl acetate) has the best performance on the yield, while the polar solvent (ethanol) was the best for extracting TFC compounds in the bitter melon fruit and leaves.

Abstract: Tomatoes are one of the most consumed vegetables in the world. Unfortunately, obtaining a high quality tomato yield in our latitudes is inconceivable without additional lighting. Changes in biochemical composition are mainly dependent on the light received by the plant. During the winter months, natural daylight at 55 ° latitude is insufficient to provide the necessary vegetation for fruit-bearing vegetables. The aim of this study is to investigate the changes in the biochemical composition of tomato fruits by using less conventional lighting methods, which could offer potential energy savings by providing higher levels of biologically active substances in tomatoes. The study was conducted in a greenhouse of Latvia University of Life Sciences and Technologies during the winter season 2018-2019, using a 16-hour photoperiod. LED, Induction, and High Pressure Sodium Lamps (as control) were used in the study. These lighting devices, with some differences, simulate daylight. Three tomato cultivars: ‘Diamont F1’, Encor F1’and ‘Balzano F1’were studied. The study specified the tomato yield and the following biochemical parameters: soluble sugars (BRIX), vitamin C, organic acids, lycopene, carotenoids, phenols and flavonoids. As expected, the yield and species-specific pigment content of tomato fruit is largely dependent on the genetics of the variety. On the other hand, biologically active compounds such as organic acids, soluble sugars, ascorbic acid and flavonoids undergo more changes due to the composition of the light. The obtained biochemical parameters give an opportunity to consider different illumination methods and the need to carry out further studies in order to confirm the conclusions. Significantly higher yields were observed in the variant with conventionally used high pressure sodium lamps. In mean time, it should be noted that in the variant with LED lamps, higher content of lycopene as well as phenols and vitamin C were observed.

Abstract: In the research chokeberries from five different geographic regions of Latvia were analysed. All collected samples were split in two parts: one of them was frozen and the second part was dried. Then extracts were prepared from frozen or dried berries in 70% ethanol/water or 10% glycerol/ethanol and 50% – 95% ethanol/water/HCl mixtures. The total phenolic content for the extracts was determined using the Folin-Ciocalteu method, total flavonoid content by rutin as standard and antioxidant activity by DPPH method. To identify and quantify the chemical compounds in the chokeberries, the analyses were performed with HPLC-DAD using absolute calibration and UHPLC-MS methods.

Abstract: Special Region of Yogyakarta is one of the regions that has high potential for natural disasters. Food is the most consumable material which is needed when natural disasters occur. An alternative form of food preservative is needed to maintain nutritious foods that will be distributed to the victims of natural disasters. The foods must still appropriate to eat. In this research, watermelon rind was chosen as an ingredient to make natural preservatives because they contain flavonoids and anthocyanins. This research aims were to determine the total content of anthocyanins, flavonoids and phenolics in the red watermelon rind and yellow watermelon rind, also to determine the effect of chitosan composition to the ability of flavonoids and phenolics release in the food. This research was carried out by extraction and encapsulation methods. The analysis included the content of Total Anthocyanin (TA), Total Flavonoids (TF) and Total Phenolic (TPC) in the supernatant. The other analysis was in vitro tests that was done to know the ability of flavonoids and phenolics release in the food. The total anthocyanin content in the red watermelon rind was 0.0334 mg L^-1 while in the yellow watermelon rind was 0.0668 mg L^-1. The total content of flavonoids in the red watermelon rind was 0.7369 g mL^-1, while in the yellow watermelon rind was 0.3296 g mL^-1. The total phenolic content of red watermelon rind was 0.3669 g mL^-1, while in the yellow watermelon rind was 0.2273 g mL^-1. In both of red and yellow watermelon rind, the highest release of flavonoid and phenolic levels showed in the variations of chitosan mass 0.4 grams. The highest flavonoid content released was 0.0638 g mL^-1 in red watermelon rind and 0.0702 g mL^-1 in yellow watermelon rind. The highest phenolic content released was 0.0321 g mL^-1 in red watermelon rind and 0.0408 g mL^-1 in yellow watermelon rind.

Abstract: Transgenic differently over-expressed cDNA involving in flavonoid biosynthesis (FLAVONOL SYNTHASE: FLS and TRANSPARENT TESTA 8: TT8) and wild type plants were grown in the culturing room radiated with fluorescent light. Flowers of each transgenic and WT were collected and extracted with acidic methanol. The flower extracts were analyzed for the relative content of each flavonoid subgroup by spectrophotometry. The result showed that the both transgenic extracts contained flavanone and flavone higher than WT extract did. The FLS extract contained the highest amount of flavonol content (1.4 times) following with the TT8 extracts (1.25 times) comparing to WT extract. The TT8 extract has anthocyanin content approximately 3 times, while the FLS extract has only 0.5 times of WT. The extract was used to evaluate the antioxidant capacity by ABTS and DPPH methods. The result showed that, both transgenic extracts have a better antioxidant capacity than WT extract. Both transgenic extracts have similar results of EC50 performed by DPPH method, however the TT8 extracts showed the highest antioxidant capacity under ABTS experimental condition. Therefore, types and concentration of flavonoids in the extract could directly affect the antioxidant capacity.

Abstract: The rapid developments in nanoscience, and its applications on biomedical areas have a large impact on drug delivery, tissue engineering, sensing, and diagnosis. Gold is widely investigated nanomaterial for the last couple of decades, since it has unique surface properties and very low toxicity to biological environment. In this work, we present a novel synthesis of gold nanoparticles (GNPs) exhibiting both visible and near-IR absorbance without agglomeration. The surface of GNPs were analyzed by routine methods and the binding kinetics were investigated by Surface Plasmon Resonance (SPR) Spectroscopy. The unique optical properties of near-IR asorbing GNP colloids hold promise for biological applications.

Abstract: Accumulating scientific evidence suggests that medicinal plant-associated microbiota has a significant role in biosynthesis of pharmacologically relevant compounds. Suppression of S. nigra microbiota by an antibiotic treatment leads to a decreased emission of volatile terpenoids from S. nigra flowers and an altered metabolome of a host plant. However, it is not known if suppression of microbiota also affects an abundance of health promoting compounds and pharmacologically relevant properties of S. nigra. The present study reveals, that suppression of phyllospheric microbiota by an antibiotic treatment affects total phenolic content (TPC), anti-radical activity (ARA) and total flavonol content (Flav) of wild S. nigra flowers. Significance analysis of metabolites (SAM) performed using ultra high performance liquid chromatography-time of flight-masspectrometry (UHPLC-TOF-MS) based metabolomics data identifies pharmacologically relevant flavonols as metabolites discriminating between antibiotic treated and control flowers of S. nigra. Reported results substantiate need for a research investigating an effect of microbiota suppression on a biological activity of S. nigra flowers.

Abstract: The present study reports the analytical approaches for characterization of teeth whitening gels based on natural extracts of fruits and medicinal plant. High performance liquid chromatography (HPLC) with UV detection were used for identification and quantification of (oxalic, citric, tartaric, malic, succinic and fumaric acids), flavonoids (catechin, epicatechin, rutin and quercetin) and phenolic acids (vanillic acid, p-coumaric acid, ferullic acid) from studied gels samples used for teeth whitening. The organic acids were used as active agent with action in tooth discoloration and stain removal. Organic acids were separated through a Carbosep Coregel 87H3 column at 35°C and detection at 214 nm. The mobile phase was the sulphuric acid 0.005 M solution. The total quantity of organic acids of these gel samples was determined. The action of flavonoids have controlled dental caries and inhibited plaque formation. Separation of flavonoids and phenolic acids was carried out on Lichrosorb RP-C18 column at 40 oC and detection at 290 nm. The mobile phase was a mixture of methanol and solution 0.1% formic acid in a gradient elution. The flavonoids, catechin, epicatechin, rutin and quercetin and phenolic acids, vanillic acid, p-coumaric acid, ferullic acid, were determined quantitative in the teeth whitening gels on natural extracts of fruits and medicinal plant.