Folin-Ciocalteu Assay Research Articles

Total phenolic content, flavonoid content and antioxidant potential of Petasites hybridus and related species from Croatia and considerations regarding their pharmaceutical significance.

Extracts obtained from common butterbur (Petasites hybridus), standardized to petasins, are existing pharmaceutical options for the treatment and/or prevention of allergic rhinitis (leaves) and migraine (rhizomes). In this study, the total phenolic content, flavonoid content, and antioxidant potential of ten samples of Croatian Petasites species (four P. hybridus, four P. albus, one P. kabli kianus, and one P. paradoxus) obtained by ultrasound-assisted extraction of leaves were compared. The total phenolic content (Folin-Ciocalteu assay) of methanolic leaf extracts ranged from 4.43 ± 0.09 to 10.76 ± 0.60 mg gallic acid equivalent g-1 dry mass (mg GAE g-1 DM) for P. hybridus and from 6.66 ± 0.43 to 19.92 ± 2.90 mg GAE g-1 DM for P. albus samples, while those of P. kablikianus and P. paradoxus were equal to 7.56 ± 0.17 mg GAE g-1 DM and 10.22 ± 0.46 mg GAE g-1 DM, respectively. Flavonoid content (AlCl3 assay) varied between 2.51 ± 0.10 and 4.03 ± 0.08 mg quercetin equivalent g-1 dry mass (mg QE g-1 DM) for P. hybridus and between 2.21 ± 0.09 and 5.22 ± 0.02 mg QE g-1 DM for P. albus samples, while those of P. kablikianus and P. paradoxus were equal to 5.59 ± 0.05 mg QE g-1 DM and 5.50 ± 0.09 mg QE g-1 DM, respectively. Antioxidant potential was in high correlation with total phenolic content (r = 0.93, p < 0.001). Due to the expected contribution of plant polyphenols and flavonoids to the activity of butterbur extracts and their observed great variabilities, determining the content of these compounds may be of interest to the pharmaceutical industry.

Mineral composition and antioxidant activity of partially digested coffee “Kopi Luwak”

Background: Kopi Luwak is a rare type of coffee, that is partially digested in the Asian palm civet’s digestive tract before roasting. It therefore possesses a distinctive flavor and unique properties, shaped by the digestive enzymes in the civet's intestine. Objective: In this study, the differences of mineral composition, antioxidant potency and total polyphenol amount between commercially available Kopi Luwak and regular coffees (without digestive fermentation) were evaluated. Methods: Twenty-one regular type of coffee bean and 17 of Kopi Luwak bean were purchased from local markets or Kopi Luwak production company in Indonesia. The samples were then analyzed for the levels of 23 minerals (Al, As, Ba, Bi, Ca, Cd, Co, Cr, Cs, Cu, Fe, Li, Mg, Mn, Mo, Ni, Pb, Rb, Se, Sn, Sr, V and Zn) using ICP-MS system. The total polyphenol amount and antioxidant activity were evaluated using Folin-Ciocalteu assay and DPPH (1,1-Diphenyl-2-picrylhydrazyl) radical scavenging assay, respectively. Results: Of these 23 minerals, the concentrations of Mn and Ba were significantly lower in Kopi Luwak than in regular coffee. Otherwise, the concentrations of Cu and Rb in Kopi Luwak were significantly higher than those in regular coffee. The IC50 value on DPPH radical scavenging assay of Kopi Luwak (61.4±2.8 mg/dL) was significantly lower than that of regular coffee (93.6±1.9 mg/dL). Total polyphenol amount for Kopi Luwak was significantly higher than regular coffee. The correlation factor between these factors was r = -0.5910 and p &lt; 0.001. Conclusion: Kopi Luwak had lower concentrations of Mn and Ba, but higher levels of Cu and Rb compared to regular coffee. Additionally, Kopi Luwak exerted strong antioxidant activity and contained higher polyphenol amounts than regular coffee. Thus, our findings imply that Kopi Luwak is an important candidate for functional foods. Keywords: antioxidant potency, ICP-MS, Kopi Luwak, mineral composition, polyphenols

Changes in the total phenolic contents, chlorogenic acid, and caffeine of coffee cups regarding different brewing methods

Coffee is among the most popular beverages consumed worldwide due to its taste, flavor, and alertness effects on drinkers. Besides, caffeine and chlorogenic acid are known as featured compounds of coffee, and there are various phenolic compounds, that demonstrate many benefits for human health. However, the concentrations of those compounds ingested into the human body are greatly dependent on how coffee infusions are prepared. The extraction efficiency of phenolic compounds, caffeine, and chlorogenic acid in the Arabica and Robusta coffee obtained from the light, medium, and dark roasting levels, using the hot brew (at 50°C and 90°C) and cold brew methods was studied. The total phenolic contents (TPCs) were measured by the Folin-Ciocalteu assay, while the first -order derivative spectrophotometry was used to determine the caffeine and chlorogenic acid. Generally, light-roasted Robusta had the highest caffeine (2.10±0.017% w/w), chlorogenic acid (5.63±0.011% w/w), and TPCs (45.5±0.9 mg GAE/g). For brewing experiments, 10 g of coffee was brewed (100 mL of water) for different extraction times. The results show that hot brewing at 90°C was the most efficient method for extracting the TPCs and chlorogenic acid, while cold brewing was better for extracting caffeine. Extraction efficiency increased with longer extraction times, especially for the light roasting level.

Investigation of the Anticholinesterase and Antioxidant Activity of Several Iranian Thymus caramanicus Populations

Background: Thymus extracts have become attractive targets for screening bioactive compounds with potential applications in pharmaceuticals, food, and cosmetics industries. Objectives: This is the first report assessing the anticholinesterase and antioxidant activities, along with total phenolic and flavonoid contents (TPC and TFC), of hydroethanolic extracts from six populations of Thymus caramanicus Jalas at vegetative and flowering stages, collected from different regions in Kerman province, Iran. Methods: The anticholinesterase and antioxidant activity, as well as TPC and TFC of T. caramanicus hydroethanolic extracts, were evaluated using Ellman, DPPH, Folin-Ciocalteu, and aluminum chloride assays, respectively. Results: All extracts inhibited both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes, with most showing a stronger effect on AChE. The extract T2-F exhibited the highest anti-AChE (IC50: 28.74 ± 0.21 µg/mL) and anti-BuChE (IC50: 65.49 ± 0.81 µg/mL) activities. The DPPH results indicated overall suitable antioxidant activity, with T4-F showing the highest antioxidant capacity (IC50: 16.22 ± 0.07 µg/mL), though about 4.2 times lower than ascorbic acid. The TPC (76.60 ± 0.98 - 211.73 ± 2.13 mg GAE/g extract) and TFC (19.15 ± 0.09 - 53.90 ± 0.13 mg QE/g extract) analyses revealed that T6-V and T5-F are rich sources of polyphenolic and flavonoid compounds. Pearson’s correlation analysis showed no direct correlation between TPC and TFC with their anticholinesterase and antioxidant activities. Conclusions: The hydroethanolic extracts of T. caramanicus demonstrated significant anticholinesterase and antioxidant activities, making them promising candidates for further studies aimed at developing therapeutic compounds with dual anticholinesterase and antioxidant properties, potentially for treating Alzheimer's disease (AD).

Impact of post-harvest processing and roasting conditions on the physicochemical properties, phenolic compounds, and antioxidant capacity of cocoa beans from the Brazilian Amazon

Interest in cocoa (Theobroma cacao L.) and its derivatives has grown mainly due to the high concentration of phenolic compounds (PC), which exhibit potentially beneficial effects on human health. Brazil is the sixth-largest producer of cocoa beans worldwide, with the Amazon region, particularly the state of Pará, playing an increasingly significant role in this production. This study evaluated the effects of pod storage, fermentation time, type of drying platform, municipality and roasting time and temperature on cocoa beans from the Brazilian Amazon. Parameters such as moisture, pH, and cut test were assessed, and individual phenolic compounds were quantified by HPLC-DAD. The Folin-Ciocalteu assay was used to evaluate total phenolic compounds (TPC), and antioxidant capacity was measured using DPPH and ORAC methods. Results showed that the phenolic content and antioxidant capacity of the beans are influenced by the municipality of origin. Fermentation time was the pre-processing condition that most significantly influenced the physicochemical and bioactive properties of the beans, causing reductions of 55–76% in individual phenolic compounds and 43.5–60.57% in antioxidant capacity after seven days. While roasting tends to degrade most phenolic compounds, catechin can form or stabilize at higher temperatures and longer roasting times.

Effect of subfractions of Allium mongolicum Regel methanolic extract on the proliferation of HepG2 and MCF-7 cells

The aerial part of Allium mongolicum Regel (AMR) which is abundant in the southeastern regions of Mongolia, is used as a food spice. When the crude extracts of this plant were prepared and used for the experiments different biological activities were observed because the extracts contained many polar to nonpolar compounds. This study aimed to prepare subfractions from the crude methanolic extract of AMR and to compare their antiproliferative effects on human cancer cells (HepG2, and MCF-7 cells). The methanolic extracts of AMR were fractionated into six subfractions (methanol, hexane, dichloromethane, ethyl acetate, butanol, and water residue) by solvent–solvent partitioning. The total phenolic content (TPC) was measured by the Folin-Ciocalteu assay. The antioxidant activity of the sub-fractions was determined via DPPH⋅ and ABTS⋅+ assays. Subfraction antiproliferative activity on human cancer cells, HepG2 and MCF-7 cells, was determined by MTS assay. Subfractions showed completely distinct antioxidant and antiproliferative activities (p < 0.001). The highest TPC was in the ethyl acetate fraction (165.4 ± 0.5 mg GAE/g), and the TPC following the addition of dichloromethane, butanol, and methanol. The lowest two were in the n-hexane and water residue fractions. The ethyl acetate fraction showed the highest free radical scavenging activity in both the DPPH⋅ and ABTS⋅+ assays (660.0 ± 5.24 µM TE/g dw the DPPH⋅ assay; 312.7 ± 5.6 µM TE/g dw the ABTS⋅+ assay). The dichloromethane subfraction affected HepG2 cell proliferation and reduced viable cancer cells. Additionally, the dichloromethane and hexane subfractions affects MCF-7 cell proliferation by reducing the number of viable cancer cells. Subfraction methanolic extract by solvent partitioning is helpful for identifying biologically active compounds that show antiproliferative activity.

Advanced Extraction Techniques Combined with Natural Deep Eutectic Solvents for Extracting Phenolic Compounds from Pomegranate (Punica granatum L.) Peels.

Pomegranate (Punica granatum L.) peel is a potential source of bioactive phenolic compounds such as ellagic acid and α- and β-punicalagin. This work explores the efficiency of natural deep eutectic solvents combined with ultrasound-assisted extraction (UAE) and pressurized liquid extraction (PLE) for their extraction. Five NaDESs were evaluated by employing UAE (25 °C, for 50 min) to determine their total phenolic content (Folin-Ciocalteu assay) and ellagic acid and α- and β-punicalagin contents (high-performance liquid chromatography (HPLC-DAD)). The NaDES composed of choline chloride (ChCl) and glycerol (Gly) (1:2, molar ratio) was the most efficient in the UAE when compared with the rest of the NaDESs and water extracts. Therefore, ChCl:Gly was further evaluated using PLE at different temperatures (40, 80, 120 and 160 °C). The PLE-NaDES extract obtained at 80 °C for 20 min at 1500 psi exhibited the highest contents of ellagic acid and α- and β-punicalagin compared to the rest of the temperatures and PLE-water extracts obtained under the same extraction conditions. Combining UAE or PLE with a NaDES emerges as a sustainable alternative for extracting ellagic acid and α- and β-punicalagin from pomegranate peel.

Comparative LC–MS-based metabolite profiling, antioxidant, and antibacterial properties of Bunium bulbocastanum tubers from two regions in Algeria

Traditional herbalists have been relied on for many years by Algerians to cure a wide range of diseases. Regardless of their nutritional values, mushrooms have chemical properties that make them attractive, beneficial, and more likely to be studied by researchers, according to ethnobotanical literature on traditional phytotherapy. Among all the edible mushrooms, tubers are a type of fungus that are traditionally used in fine dining and have garnered attention recently because of their many therapeutic applications. This research delves into a meticulous analysis of bioactive constituents in Bunium bulbocastanum tubers, sourced from Mostaganem and Relizane regions, with a keen focus on polyphenols, flavonoids, and condensed tannins. The quantification of total phenolic content was executed through the Folin-Ciocalteu assay, while flavonoids were assessed via the aluminum chloride colorimetric method. In addition, condensed tannins were evaluated in this study. Antioxidant capacities were scrutinized employing the 2,2′-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Microbial inhibition studies were conducted against five benchmark bacterial strains, utilizing the agar disc diffusion technique. Furthermore, a comprehensive liquid chromatography–mass spectrometry (LC–MS) analysis was performed to identify and quantify bioactive compounds. The findings underscore that the Mostaganem extracts were particularly rich in polyphenols (11.65 mg GAE/g of extract) and tannins (1.30 mg CE/g of extract), while the Relizane extracts boasted significant flavonoid concentrations (9.421 mg QE/g of extract). Notably, 4-methylguaiacol (82.04 mg/L), caffeic acid dimethyl ether (27.76 mg/L), syringic acid (20.48 mg/L), and naringenin (16.05 mg/L) emerged as the predominant volatile compounds. Compositional investigation of the extracts by LC–MS confirmed the presence of various compounds that were linked to the bioactivities exhibited by B. bulbocastanum tubers. These findings demonstrate the effective antibacterial and antioxidant properties of B. bulbocastanum tubers, indicating their potential use in pharmaceutical and nutraceutical applications.

PSLBII-22 Antioxidant potential and in vitro digestibility of two varieties of industrial hemp (cannabis sativa) supplemented in beef cattle diet

Abstract The use of industrial hemp in animal research is gaining much attention in recent years. However, there is little information known about the antioxidant potential and digestibility of different hemp varieties supplemented in cattle diet. The objective of this study was to determine the antioxidant potential and in vitro digestibility of different hemp varieties supplemented in cattle diet. Two varieties of industrial hemp were supplemented at 20 g in 200 g of commercial diet into Trt 1 (0 g of hemp), Trt 2 (20 g of sour kush variety) and Trt 3 (20 g of rogue variety) for in vitro digestibility study using Ankom DaisyII incubator. The experimental design was a 3 x 3 factorial design with 3 feed types and 3 digestion times (12, 24, 36 h). Rumen samples were used as inoculum with the recommended buffers for the DaisyII incubator. Total polyphenol content and antioxidant capacity were determined using Folin-Ciocalteu assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay respectively. Data were analyzed using mixed procedure in SAS 9.4, means were separated with Tukey at 5% alpha. There was no significant (P &amp;lt; 0.05) difference in antioxidant capacity and digestibility between the two varieties of industrial hemp. Likewise, no significant interactions was observed. Conclusively, the two industrial hemp varieties used in this study had similar antioxidant capacities and digestibility, thereby, similar benefits can be derived from supplementing any of these varieties in animal diet.

Determination of antioxidant capacity and phenolic content of haskap berries (Lonicera caerulea L.) by attenuated total reflectance-Fourier transformed-infrared spectroscopy

The total phenolic content (TPC) and antioxidant capacity (TAC) of haskap berries cultivated in various locations across Alberta were analyzed using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The Folin–Ciocalteu assay was used to determine TPC, while TAC was quantified by 2,2-diphenyl-1-picrylhydrazl radicals (DPPH) assay and oxygen radical absorbance capacity (ORAC) assay. Three tenfold cross-validated partial least-squares regression (PLSR) models and three fivefold cross-validated deep learning models were developed separately based on FT-IR spectra collected from 22 haskap berry samples and their corresponding reference values determined through Folin-Ciocalteu, DPPH, and ORAC assays. The deep learning models (R2 = 0.95, 0.93, and 0.90 for Folin-Ciocalteu, DPPH, and ORAC assays, respectively) demonstrated better prediction capability compared to the PLSR models (R2 = 0.74, 0.72, and 0.66 for Folin-Ciocalteu, DPPH, and ORAC assays, respectively). In addition, PLS loading plots indicated that phenolic contents and polysaccharides in haskap berries could contribute to their antioxidant capacity. Using ATR-FTIR to estimate the TPC and TAC of fruits offers a rapid alternative to the conventional chemical assays.

A multifunctional natural treasure based on a “one stone, many birds” strategy for designing health-promoting applications: Tordyliumapulum

Wild plants provide important bioactive compounds, and their analysis relies heavily on selecting the right extraction techniques and solvents. This study was conducted to determine the phenolic content and biopharmaceutical potential of four different extracts (ethyl acetate, ethanol, 70% ethanol, and water) from the aerial parts of wild plant Tordylium apulum L. The biochemical profile of the extract was screened using high performance liquid chromatography -mass spectrometry (HPLC-MS) analysis. The total phenolic and flavonoid content was examined using the Folin-Ciocalteu assay and the aluminium trichloride assay, respectively. The antioxidant activity was evaluated through several tests, including 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), cupric reducing antioxidant capacity (CUPRAC), ferric reducing antioxidant power (FRAP), phosphomolybdenum (PBD), and metal chelating activity (MCA). Five types of enzyme inhibition activity were tested against acetylcholinesterase (AChE), butrylcholinesterase (BChE), tyrosinase, α-amylase, and α-glucosidase. Additionally, For the first time, the inhibitory activity of T. apulum extract against human carbonic anhydrase isoenzymes I and II (hCA-I and hCA-II) was evaluated. Fifty-five compounds for negative ionization mode, and twenty-eight compounds for positive ionization mode were recorded in HPLC-MS analysis and they were polyphenolic, flavonoids, carbohydrates, sugar alcohol and amino acids. These results indicate that different solvents extract varying levels of antioxidants from T. apulum, with ethanol and water extracts generally exhibiting superior antioxidant activities. The ethanol extract of T. apulum exhibited the maximum contents of total phenolics measuring 33.71 mg gallic acid equivalent (GAE)/g. The ethanol extract exhibited the highest inhibition of AChE with 2.28 mg galanthamine equivalent (GALAE)/g. The ethyl acetate and ethanol extracts also showed the highest hCA-I and hCA-II inhibition potential, respectively. The ethanol-water and water extracts acted on the biofilm of E. coli (49.93% and 45.22%, respectively), and the biofilm of P. aeruginosa (50.68% and 44.46%, respectively). The extracts were tested on different cell lines for cytotoxic potentials and in particular the water extract induced the apoptotic pathways in cervical cancer (HELA) cell lines. In conclusion, T. apulum exhibit multidirectional biological properties and it could be considered as a versatile agent for the development of health-promoting applications.

Potentiometry in determining the antioxidant capacity of compounds of different hydrophilicity in the joint presence using mixed solvents and surfactants.

In this work, for the first time, the potentiometric method was used to determine the antioxidant capacity (AOC) of compounds of different hydrophilicity in the joint presence using mixed solvents and surfactants. The AOC of model solutions of antioxidants of different hydrophilicity was determined separately and in the joint presence in the media of phosphate buffer-surfactant and mixed solvents-surfactant, using as an example the ascorbic acid and the α-tocopherol. It was shown that the surfactant Triton X-100 is able to solubilize α-tocopherol under the selected conditions, allows to obtain reproducible and accurate results, and has less effect on the equilibrium rate of the K3[Fe(CN)6]/K4[Fe(CN)6] system. Phosphate buffer-ethanol and phosphate buffer-acetonitrile media in the 3:2 ratio with Triton X-100 (5mmol/dm3) were chosen as the analysis conditions (RSD ≤ 6%). The range of determined concentrations was (0.006-0.5)m mmol/dm3 in phosphate buffer-ethanol and (0.006-0.3)m mmol/dm3 in phosphate buffer-acetonitrile. AOC of raw materials infusions was determined in selected media. The positive correlation with the well-known Folin-Ciocalteu assay was obtained.

Hop leaves: From waste to a valuable source of bioactive compounds – A multidisciplinary approach to investigating potential applications

After harvesting of cones used for beer production, the remaining hop vegetative biomass requires disposal. The hop plant contains bioactive compounds in all its parts—cones, leaves, and roots—exhibiting interesting antioxidant, antiviral, and antibacterial properties. In this work, extracts obtained from hop leaves, a plant material often neglected in the hop cultivation, have been investigated; the qualitative UHPLC-MS/MS and GC-TOF-MS characterization revealed the presence of bioactive compounds such as polyphenols, α- and β-acids and terpenes are present. The extract retained antioxidant activity, as verified by Folin-Ciocalteu, DPPH, ABTS and FRAP assays, and demonstrated some antimicrobial activity when combined with antibiotics, particularly against Gram-positive bacterial strains. Additionally, the extracts showed an ability to interact with proteins as human insulin, amyloid beta peptide, mucin and bovine serum albumin (BSA), has been detected, indicating their potential to counteract inflammatory processes and protect against Alzheimer's disease. These findings suggest that hop vegetative biomass, typically considered waste, can be potentially transformed into a valuable resource with applications in various fields, from nutraceuticals to pharmaceuticals and cosmetics, aligning with a circular economy perspective.

Microbead-Based Colorimetric and Portable Sensors for Polyphenol Detection.

Natural polyphenols found in health supplements and drinks have antioxidant and anti-inflammatory properties. In particular, to determine the beneficial qualities of antioxidant drinks and beverages, consumers demand precise quantification of the total amount of polyphenols as on-site detection. Herein, we developed a new concept of portable beads suitable for the field detection available: colorimetric quantification of polyphenols equipped with color converting software applications in a smartphone or tablet PC. The yellowish beads contain ferric ions to react with polyphenol to produce blackish metal-phenolic complexes. It is simple to perform the detection procedure: dipping the beads in the analytical sample and out-taking a photo-converting into RGB color values and quantification of the existed polyphenol. The overall process was completed within 5 min. Compared with the Folin-Ciocalteu assay, which is a representative optical sensor kit for total phenolic content, the bead-based sensor showed a better limit of detection of 0.0415 mM for tannic acid and comparable sensing capability for a polyphenol-containing plant extract and brewed tea. The beads conserved the shape and sensitivity after months of storage or under environmental interference such as a change in the temperature.

It Is Not All about Alkaloids-Overlooked Secondary Constituents in Roots and Rhizomes of Gelsemium sempervirens (L.) J.St.-Hil.

Gelsemium sempervirens (L.) J.St.-Hil. is an evergreen shrub occurring naturally in North and Middle America. So far, more than 120 alkaloids have been identified in this plant in addition to steroids, coumarins and iridoids, and its use in traditional medicine has been traced back to these compound classes. However, a comprehensive phytochemical investigation of the plant with a special focus on further compound classes has not yet been performed. Therefore, the present study aimed at an extensive HPLC-MSn characterization of secondary metabolites and, for the first time, reports the occurrence of various depsides and phenolic glycerides in G. sempervirens roots and rhizomes, consisting of benzoic and cinnamic acid derivatives as well as dicarboxylic acids. Furthermore, mono- and disaccharides were assigned by GC-MS. Applying the Folin-Ciocalteu assay, the phenolic content of extracts obtained with different solvents was estimated to range from 30 to 50% calculated as chlorogenic acid equivalents per g dry weight and was related to the DPPH radical scavenging activity of the respective extracts. Upon lactic acid fermentation of aqueous G. sempervirens extracts, degradation of phenolic esters was observed going along with the formation of low-molecular volatile metabolites.

Extraction of Total Phenol and Antioxidant Activity of Butterfly Pea Flower (Clitoria ternatea L.) Extracts by Ultrasound-Assisted and Maceration Extraction

Butterfly pea flower, also known as Asian pigeon wings, has been widely used as an ingredient in food and medicine due to the high content of various types of antioxidants that are beneficial to health. One of the technologies used to extract the bioactive compound from the plant is the ultrasound-assisted extraction (UAE) method. This study aimed to investigate the effect of different extraction times from 10 min to 30 min and types of solvent: water, aqueous methanol and aqueous ethanol on the phenolic compound and antioxidant activity present in the butterfly pea flower. The total phenolic content (TPC) was determined using Folin-Ciocalteu assay while the antioxidant was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay. Based on this study, the optimal condition to increase the extract yield from butterfly pea flower was found to be at a 20-min sonication, while the highest TPC and antioxidant activity were achieved at a 30-min sonication using aqueous methanol. Compared with maceration, UAE demonstrated better results in percentage yield, TPC and antioxidant activity when using aqueous methanol. This approach indicated that UAE is an efficient technique for obtaining bioactive compounds from butterfly pea flowers.

Physicochemical properties, antioxidant activity and phytochemical profiling of Australian Tetragonula carbonaria cerumen

This study investigated the physicochemical and antioxidant properties of stingless bee (Tetragonula carbonaria) cerumen from Australia, while also identifying some phenolic constituents using High-Performance Thin-Layer Chromatography (HPTLC). The antioxidant activity of the ethanolic T. carbonaria cerumen extracts was determined using a Ferric Reducing Antioxidant Power (FRAP) assay and a HPTLC-DPPH approach was used to identify the constituents that contribute to the antioxidant activity of the cerumen samples. For the determination of the total phenolic content (TPC), a modified Folin-Ciocalteu assay was carried out. The FRAP values ranged from 5.19 ± 0.40 to 16.2 ± 0.70 mmol Fe2+/kg of raw cerumen and the TPC values from 3.77 ± 0.12 to 81.3 ± 2.04 mg GAE/g of raw cerumen. The HPTLC analysis revealed the presence of gallic acid and kaempferol in the ethanolic T. carbonaria cerumen extracts which contribute to the antioxidant activity of the samples. The findings of the study demonstrate the antioxidant activity of Australian T. carbonaria cerumen and highlight the importance of more research into its chemical composition, bioactivity and potential therapeutical use.

Evaluation of In Vitro-Derived Hop Plantlets, cv. Columbus and Magnum, as Potential Source of Bioactive Compounds.

The demand for bioactive secondary metabolites of natural origin is increasing every day. Micropropagation could be a strategy to respond more quickly to market demands, regardless of seasonality. This research aims to evaluate in vitro-grown plants of two hop varieties, namely Columbus and Magnum, as a potential source of bioactive compounds. The extracts were characterized in terms of total phenolic content by a Folin-Ciocalteu assay and antioxidant capacity by DPPH•, ABTS+, and FRAP assays. The bioactive compound profile of the extracts from both varieties was determined by using UPLC-ESI-QqQ-MS/MS. The results confirmed richness in (poly)phenols and other secondary metabolites of the in vitro-grown hop plantlets. Thirty-two compounds belonging to the major families of phytochemicals characteristic of the species were identified, and twenty-six were quantified, mainly flavonoids, including xanthohumol and isoxanthohumol, phenolic acids, as well as α- and β-acids. This study confirms the validity of in vitro-derived hop plantlets as source of bioactive compounds to be used in the nutraceutical, pharmaceutical, and food industries.

Physicochemical Properties, Antioxidant Activity, and High-Performance Thin-Layer Chromatography Profiling of Propolis Samples from Western Australia.

This study reports on the physicochemical and antioxidant properties of propolis samples from various regions across Western Australia and identifies some phenolic constituents using high-performance thin-layer chromatography (HPTLC). Total phenolic content (TPC) was determined using a modified Folin-Ciocalteu assay, and antioxidant activity was investigated with the Ferric Reducing Antioxidant Power (FRAP) assay and also visualised and semi-quantified by HPTLC-DPPH analysis. TPC values ranged from 9.26 to 59.3 mg gallic acid equivalent/g of raw propolis and FRAP assay data from 4.34 to 53.8 mmol Fe2+ mmol/kg of raw propolis, although some of these variations might be related to differences in extraction yields obtained with 70% ethanol. The presence of luteolin, taxifolin, naringenin, and 4-hydroxyphenylacetic acid was confirmed based on a comprehensive, validated matching approach against an HPTLC-derived database. The findings of the study highlight the importance of future research on the chemical composition and bioactivity of Western Australian propolis.

Antioxidant Properties of Lemuni Leaves (Vitex trifolia var. purpurea) in Different Concentrations of Ethanol-Water Solvent Extraction

Vitex trifolia var. purpurea leaves (Lemuni leaves) is considered as a traditional medicine due to their antioxidant property. The antioxidant properties of Lemuni leaves depends on the concentration of ethanol-water solvent. Therefore, this current study intended to identify the antioxidant activity of Lemuni leaves (Vitex trifolia var. purpurea) in different concentrations of ethanol-water solvent extraction. Four ethanol-water concentrations were prepared (water extract (0% ethanol), 25% ethanol extract, 50% ethanol extract, and 75% ethanol extract). The antioxidant properties of Lemuni leaves were evaluated by Folin-Ciocalteu assay, aluminium chloride calorimetric method while 2,2’-diphenyl-1-picrylhydrazyl (DPPH) assay and 2,2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assay were used to measure the antioxidant activities of the extracts. The experimental results showed that 75% ethanol extract had the highest (p&lt;0.05) total phenolic content (94.69 ± 4.75mg GAE/g DW) and total flavonoid content (30.76 ± 2.85mg QE/g DW) significantly. The 75% ethanol extract also had the significantly lowest (p&lt;0.05) IC50 value for DPPH (3.56 ± 0.11 mg/mL) and ABTS (2.01 ± 0.05 mg/mL) assays. Strong correlations were discovered between the total flavonoid content, total phenolic content with antioxidant properties of Lemuni leaves at different ethanol-water ratio by DPPH (r= -0.816; r= -0.824) and ABTS assays (r= -0.929; r= -0.920).The significantly elevated antioxidant properties of the 75% ethanol extract suggest promising applications in health supplements, pharmaceuticals, skincare products, biomedical research, and commercial ventures.