Total Flavonoid Content Values Research Articles

Phytochemicals, Antioxidant, and Antidiabetic Effects of Ranunculus hirtellus Aerial Parts and Roots: Methanol and Aqueous Extracts.

Ranunculus hirtellus, also known as crowfoot (buttercup), has a rich tradition of use in various biological contexts. While antibacterial studies on extracts from this plant have been conducted, the phytochemical composition, antioxidant properties, and antidiabetic effects remain unexplored. In this study, the phytochemical, antioxidant, and antidiabetic effects of its methanol and aqueous extracts were investigated. Our approach involved gas chromatography-mass spectrometry (GC/MS), alongside quantitative and qualitative methods, for phytochemical profiles. Additionally, concerning biological activities, the antioxidant effect was assessed through 2, 2-diphenyl-pieryl hydrazyl (DPPH) and 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulfonate) (ABTS) assays, while the antidiabetic effect was examined through the α-amylase inhibitory assay. The chloroform, ethyl acetate, and n-hexane extracts of R. hirtellus revealed the presence of 14 distinct compounds. In the methanol extract, sterols, quinones, glycosides, lactones, lignin, and flavonoids were identified. The aqueous extract contained sterols, alkaloids, glycosides, triterpenes, terpenoids, quinones, leucoanthocyanins, and lactones. The total flavonoid content (TFC), total phenolic content (TPC), total tannin content (TTC), and reducing sugar content (RDC) were determined in plant extracts, and a linear relationship was found between these parameters. Additionally, the TTC, TPC, and TFC values for both extracts hovered around 0.3786, 0.0476, and 0.1864 μg/mL, respectively, across all plant concentrations, while RDC ranged from 0.9336 to 1.0119 μg/mL in all four extracts. In vitro assays demonstrated dose-dependent antidiabetic activity in both methanolic and aqueous extracts by inhibiting α-amylase. Furthermore, the antioxidant activity observed in the DPPH assay was greater in the aqueous extract compared with the methanolic extract. In addition, the ethyl acetate extract exhibited the highest inhibition among chloroform and n-hexane in the ABTS assay. The results suggest that R. hirtellus can be a potential source of natural antioxidants and antidiabetic agents, and further studies are warranted to investigate the underlying mechanisms of its therapeutic effects.

Optimizing the drying conditions of date plum (Diospyros lotus L.) to conserve its phenolic content and antioxidants for preparing a highly bioaccessible polyphenol-rich tea

AbstractDate plum (Diospyros lotus L.) fruits are a good source of bioactive compounds and antioxidants. Drying can increase the shelf life of the fruit and its applications in the food development industry. Optimizing the drying conditions can help to produce prime-quality dried date plum fruits and conserve nutrients including phytochemicals. This study used a two-factor graphics-optimal design to optimize convective drying considering the air velocity and drying temperature of date plum fruits. The independent factors considered included drying temperature (43.78–86.21 °C) and air velocities (0.54–1.96 m/s), and the responses included total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 2,2-diphenyl-1-picrylhydrazy (DPPH) radical scavenging activity of date plum fruit. The optimized drying conditions (68 °C and 1.75 m/s) resulted in desirable TPC, TFC, FRAP, and DPPH values. The findings indicated that long drying time at low temperatures significantly decreased the phenolics and antioxidants. Date plum tea with different decoction times (5, 10, and 15 min) was prepared from fruits dried at optimum conditions. A decoction time of 5 min resulted in the highest catechin, vanillic, epicatechin, syringic acid, and quercetin-3-glucoside content, which were 2.45 ± 0.04, 11.06 ± 0.11, 22.03 ± 0.11, 12.95 ± 0.08, and 9.37 ± 0.10 mg/L; respectively. In vitro gastrointestinal digestion revealed that the tea product can be a source of highly bioaccessible (> 80%) gallic acid, catechin, vanillic acid, and quercetin-3-glucoside. Applying optimized drying conditions to dehydrate date plum fruit can be useful in preparing a highly bioaccessible polyphenol-rich tea.

Comparative study of different Malaysian Stingless bee propolis: Physicochemical characterization, Phytochemical contents and Antibacterial activity

Stingless bee propolis is known to contain a variety of bioactive compounds, including phenolic and flavonoids, which have been linked to its antibacterial properties. Nevertheless, the phytochemical compositions of stingless bee propolis are significantly influenced by a complex interplay of multiple factors such as geographical origin, floral source, and bee species. This study aimed to assess the physicochemical properties, phytochemical contents, and antibacterial activity of propolis from different stingless bee species found in the same environment and ecological system. The propolis samples obtained from Heterotrigona itama, Geniotrigona thoracica and Tetrigona apicalis were subjected to physicochemical analysis to determine the pH, moisture, lipid, resin, and wax contents. The total phenolic content (TPC) and total flavonoid content (TFC) were measured by Folin-Ciocalteu colorimetric and aluminium chloride methods, respectively. The antibacterial activity was determined using the agar well diffusion method against four Gram-positive bacteria, including Bacillus cereus, Micrococcus luteus, Streptococcus mutans, and Staphylococcus aureus. The physicochemical analysis of the propolis samples yielded the following results: moisture (12.17-16.45%), lipid (2.95-9.48%), resin (39.00-51.00%), wax (26.50-37.00%), and pH (5.07-5.61). Results revealed that propolis produced by G. thoracica displayed significantly higher moisture (16.45±0.38%), and resin contents (51.00±1.41%), as well as significantly lower percentage of lipid (2.95±0.12%), and wax content (26.50±0.71%). Similarly, G. thoracica propolis extract exhibited significantly higher TPC (200.70±0.06mg/mL GAE) and TFC (141.60±3.63mg/mL QE) values compared to the other propolis samples. Additionally, G. thoracica propolis extract was significantly active against B. cereus and M. luteus with inhibition zones of 15.00 and 16.00, respectively, and minimum inhibition concentration (MIC) of 390.63μg/mL. A strong correlation was found between resin content, TPC and antibacterial activity of propolis. This study indicated that the presence of high resin content in propolis resulted in a high concentration of phenolic compounds, which contributed significantly to its antibacterial activities. Furthermore, the research highlighted the species-dependent effect of propolis on its physicochemical characteristics, phytochemical composition, and antibacterial properties. The observed antibacterial efficacy of G. thoracica propolis suggested that the propolis extract held promise as an alternative treatment option against bacterial infections. Further research is warranted to fully elucidate the specific phenolic compounds that could contribute to its antibacterial properties.

The Effect of Drying Time on the Antioxidant Properties of Single Black Garlic Powder

Black garlic is a processed product derived from fresh garlic that generally has a taste and aroma that is less preferred. A drying process is employed to increase the attractiveness of consuming black garlic. This study aims to assess the impact of the drying time on the antioxidant activity and content of antioxidant compounds such as phenolics, flavonoids, and tannins in single black garlic. The drying time is expected to yield a single black garlic powder that is more convenient for consumption, whether in capsule form or as an addition to food products. With low moisture content, single black garlic powder has a longer shelf life and high antioxidant activity, potentially commanding a higher market value. In this research, the drying time was carried out on a single black garlic using an oven for 6, 12, 18, and 24 hours. The analysis of the total phenolic content (TPC), entire tannin content (TTC), and total flavonoid content (TFC) was determined using a Uv-Vis spectrophotometer, and each component was measured concerning gallic acid equivalent for TPC, quercetin for TFC, and tannic acid for TTC. Antioxidant activity was determined using the DPPH method, and the outcomes were expressed as IC50 values. The research shows that the extended drying time leads to an augmentation of the antioxidant compound in black garlic. Drying for 24 hours produces significant outcomes, showing potent antioxidant activity with an IC50 value of 37,019 ppm (powerful antioxidant category), total phenolic content value is 44,785 ± 0,033 mgGAE/g, total flavonoid content value is 32,033 ± 0,008 mgQE/g, and total tannins content value is 74,884 ± 0,057 mgTAE/g. Statistical analysis using a one-way ANOVA showed a significant influence of drying time on TPC, TFC, and TTC (p < 0,05). The longer the drying time, the higher the antioxidant activity and the content of compounds acting as antioxidants in black garlic powder.

Heat, ultrasound, and microwave assisted extraction methods for recovering bioactive components from hawthorn fruit (Crataegus monogyna Jacq.)

AbstractIn this work, an assessment of effective solvents and extraction methods was carried out to recover the bioactive compounds from hawthorn fruit (Crataegus monogyna Jacq.). Extractions assisted by heat, microwave, and ultrasound were carried out using various organic solvents (methanol, ethanol, and isopropanol). pH differential, Folin–Ciocalteu's, and aluminum chloride methods were used to determine total monomeric anthocyanin (TMA), total phenolic compound (TPC), and total flavonoid content (TFC), consecutively. Ferric Reducing Antioxidant Power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl Hydrate (DPPH), and 2,2′- azino- bis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) assays were used to measure the antioxidant activity (AA) of the extracts. The outputs revealed that extraction methods and solvents significantly affect anthocyanin concentration, TPC, TFC, AA, and color values of hawthorn fruit extracts. Due to the highest recovered TMA (0.152 ± 0.002 mg ECy3Gl/g of dry weight), TPC (49.14 ± 0.38 mg gallic acid equivalents/g of dry weight), and TFC (18.38 ± 0.19 mg quercetin equivalents/g of dry weight) contents, the ultrasonic-assisted extraction is superior to heat and microwave-assisted extractions. Accordingly, it was also observed that the methanol solvent is more profound than ethanol and isopropanol. Further, the bioactive compounds' content and the extracts' antioxidant activity are shown to be highly correlated. Thus, hawthorn extracts are considered to have antioxidant properties because of their concentrated bioactive compounds.

Bioactive polyphenolic compounds and antioxidant potentials of two leafy vegetables in Bangladesh: the Momordica charantia and the Ipomoea aquatica

Momordica charantia and Ipomoea aquatica leaves are two green leafy vegetables in Bangladesh that are commonly consumed considering their characteristic taste and abundant availability in nature. The aim of this study was to determine the available bioactive phenolic constituents as well as total flavonoid content (TFC), tannin content (TTC), phenolic content (TPC), antioxidant activity (TAA) and DPPH radical scavenging activity (IC50) of the ethanolic extracts of M. charantia (MCE) and I. aquatica (IAE). HPLC–DAD and UV–visible spectrophotometer were used to determine the phenolic compounds and antioxidant properties, respectively. In this study, TFC, TTC, TPC, TAA and IC50 values were in the order of IAE (40.73 ± 1.0 mg QE/g) > MCE (34.60 ± 0.46 mg QE/g); MCE (40.93 ± 0.70 mg TAE/g) > IAE (31.13 ± 0.42 mg TAE/g); MCE (27.76 ± 0.58 mg GAE/g) > IAE (21.29 ± 0.43 mg GAE/g); MCE (52.03 ± 0.21 mg AAE/g) > IAE (40.77 ± 0.15 mg AAE/g) and MCE (333.22 ± 67.37 µg/mL) > IAE (560.74 ± 10.25 µg/mL). M. charantia ethanolic extracts contained five hydroxycinnamic acid: ferulic acid, chlorogenic acid, p-coumaric acid, rosmarinic acid and cinnamic acid; five flavonoids: epicatechin, quercetin, catechin, rutin hydrate and myricetin; two hydroxybenzoic acid: gallic acid and vanillic acid; and one phenolic aldehyde: vanillin. Whereas, I. aquatica extracts possessed four hydroxycinnamic acid: chlorogenic acid, p-coumaric acid, trans-ferulic acid and trans-cinnamic acid; four flavonoids: epicatechin, quercetin, catechin, and rutin hydrate; two hydroxybenzoic acid: gallic acid and vanillic acid; and one phenolic aldehyde:vanillin. These underutilised sources of leafy vegetables may be used to develop functional foods by emphasising their remarkable bioactive components.Graphical

Evaluation of antioxidant and antacid activities of crude methanol and peptide extracts of Momordica charantia, Luffa cylindrica, and Jatropha curcas

Background: There are many uses for therapeutic-based compounds in the food and pharmaceutical industries, and natural products are one of the best sources of these compounds. Momordica charantia (Family Cucurbitaceae), Luffa cylindrica (Family Cucurbitaceae), and Jatropha curcas (Family Euphorbiacece) have been documented for various medicinal applications. Objective: This study aimed to assess the anti-ulcer and antioxidant properties of M. charantia, L. cylindrica and J. curcas extracts and their crude peptide. Methods: The plant samples were collected, identified, and authenticated at Forest Herbarium, Ibadan, Nigeria. The samples were allowed to air dry, were pulverized, and then were extracted using methanol. The peptidic principles were extracted using Dichloromethane: Chloroform: Water mixtures in the ratio 1:1:0.5 and concentrated in vacuo. The peptidic extracts were screened for peptide and peptide-related compounds by TLC bioautography using Ninhydrin, Pyridine, and modified G-250 reagents. The extracts were assessed for antioxidant (2,2-diphenyl-1-picrylhydrazyl, DPPH), free radical scavenging activity, total phenolic content (TPC), total flavonoid content (TFC), and antiulcer activity. The antiulcer activity was evaluated using the artificial gastric acid neutralizing activity. Results: It was observed that all M. charantia, L. cylindrica, and J. curcas and their crude peptide extracts contain phenols and flavonoids. The TPC values of the crude methanol extracts were greater than those of the corresponding peptide extracts for all three species. The TFC of M. charantia and L. cylindrica crude methanol extracts were lower than their crude peptide extracts, while the TFC of J. curcas crude methanol extract was higher than the TFC value for its crude peptide extract. The DPPH radical scavenging activity of the crude extracts and crude peptide extract of M. charantia, L. cylindrica, and J. curcas was low when compared to the standard (Gallic acid). The M. charantia crude peptide extract had the lowest IC50 value of 282.4 μg/mL, indicating that it had better scavenging efficacy compared to the other extracts that were examined, while the lowest IC50 value was obtained from J. curcas methanol extracts (411.7 μg/mL). The result from this study shows that M. charantia, L. cylindrica, and J. curcas and their crude peptide possess artificial gastric acid neutralizing activity, which implies that they can be used as antacids to reduce the acidity of the stomach. Hence, the plants were evaluated for their efficacy in managing peptic ulcers by their ability to reduce the acidity of the stomach by raising the pH of the stomach. This is the first report on the antacid potential of Momordica charantia, Luffa cylindrica, and Jatropha curcas in literature. Conclusions: The results from this study support the ethnomedicinal claims that M. charantia, L. cylindrica, and J. curcas can be used in the management of peptic ulcers, and these plants could serve as sources of lead compounds to produce natural antiulcer drugs. There were traces of the presence of linear peptides and cyclic peptides (cysteine-rich cyclotides). Keywords: Antiulcer, Antioxidant, Peptides, Momordica charantia, Luffa cylindrica, Jatropha curcas

Characterization of the Chemical Composition and Biological Activities of Bog Bilberry (Vaccinium uliginosum L.) Leaf Extracts Obtained via Various Extraction Techniques.

This investigation aimed to assess the chemical composition and biological activities of bog bilberry (Vaccinium uliginosum L.) leaves. Hydroethanolic extracts were obtained using four extraction techniques: one conventional (CE) and three alternative methods; ultrasound (UAE), microwave (MAE) and high-pressure (HPE) extractions. Spectrophotometric analysis was conducted to determine their chemical content, including the total phenolic content (TPC) and total flavonoid content (TFC). Furthermore, their antioxidative and antimicrobial properties were evaluated. HPLC (high performance liquid chromatography) analysis identified and quantified 17 phenolic compounds, with chlorogenic acid being the predominant compound, with the lowest level (37.36 ± 0.06 mg/g) for the bog bilberry leaf extract obtained by CE and the highest levels (e.g., HPE = 44.47 ± 0.08 mg/g) for the bog bilberry leaf extracts obtained by the alternative methods. Extracts obtained by HPE, UAE and MAE presented TPC values (135.75 ± 2.86 mg GAE/g; 130.52 ± 1.99 mg GAE/g; 119.23 ± 1.79 mg GAE/g) higher than those obtained by the CE method (113.07 ± 0.98 mg GAE/g). Regarding the TFC values, similar to TPC, the highest levels were registered in the extracts obtained by alternative methods (HPE = 43.16 ± 0.12 mg QE/g; MAE = 39.79 ± 0.41 mg QE/g and UAE = 33.89 ± 0.35 mg QE/g), while the CE extract registered the lowest level, 31.47 ± 0.28 mg QE/g. In the case of DPPH (1,1-diphenyl-2-picrylhydrazyl) antioxidant activity, the extracts from HPE, UAE and MAE exhibited the strongest radical scavenging capacities of 71.14%, 63.13% and 60.84%, respectively, whereas the CE extract registered only 55.37%. According to Microbiology Reader LogPhase 600 (BioTek), a common MIC value of 8.88 mg/mL was registered for all types of extracts against Staphylococcus aureus (Gram-positive bacteria) and Salmonella enterica (Gram-negative bacteria). Moreover, the alternative extraction methods (UAE, HPE) effectively inhibited the growth of Candida parapsilosis, in comparison to the lack of inhibition from the CE method. This study provides valuable insights into bog bilberry leaf extracts, reporting a comprehensive evaluation of their chemical composition and associated biological activities, with alternative extraction methods presenting greater potential for the recovery of phenolic compounds with increased biological activities than the conventional method.

Phenolic profile of unripe areca nuts cultivated in various districts of Karnataka, India

AbstractBackgroundAnnual production of areca nut in Karnataka state exceeds 1.08 million tonnes, contributing 80% and 49% to Indian and global production, respectively. Areca nut (pericarp of Areca catechu L.) is found to be a rich source of valuable phenolic compounds. Total phenolic content (TPC) and total flavonoid content (TFC) were estimated in 21 unripe areca nut samples collected from the major areca nut growing regions of Karnataka state. Arecoline, a prominent alkaloid present in areca nut was estimated and phenolic profile of one areca nut sample was generated using UHPLC–MS/MS studies.ResultsA significant variability was found in TPC, TFC and arecoline content among the samples, belongs to different agroclimatic zones. Flavonoids were found to be the major phenolic compounds present in these unripe areca nut samples. The median values of TPC, TFC and arecoline were found to be 99.609 ± 0.002 mg gallic acid equivalent, 78.86 ± 0.007 mg catechin equivalent and 2.17 ± 0.13 mg/g of the sample on fresh weight basis. A positive correlation was found to exist between TPC and arecoline content in the green unripe areca nuts of 6–7 months' maturity. Through UHPLC–MS/MS studies, 61 prominent compounds have been identified.ConclusionThe TPC and TFC of areca nuts collected from different districts of Karnataka falling in various agroclimatic zones varied significantly. In general, the arecoline content found in all these samples was less than that reported elsewhere, and the variability among the samples was also found to be minimal. A positive correlation was observed between TPC and arecoline. UHPLC–MS/MS studies showed the presence of about 52 unique phenolic compounds.

Garcinia dulcis and Garcinia forbesii King fruit peel extract: Secondary metabolite composition, antioxidant, and elastase inhibitory activity evaluation.

Garcinia dulcis and Garcinia forbesii King are native plants from Indonesia and have tremendous potential as a source of raw medicines based on local wisdom. However, scientific data for strengthening pharmaceuticals are still limited. Therefore, it is necessary to conduct a study to strengthen and develop the potential of both plants using the approach of traditional medicine. This study aimed to explore the secondary metabolite composition and biological activity (antioxidant and antielastase) of both plants. Both samples were extracted using 70% ethanol and microwave-assisted extraction with a microwave power of 120 watts for 15 min. The extract obtained was then screened for phytochemicals using specific reagents. The total phenolic content (TPC) was determined using spectrophotometry with a 96-well microplate reader method. The total flavonoid content (TFC) was determined using the colorimetric method, whereas metabolite profiling analysis was conducted using the UPLC-QToF-MS/MS system. Meanwhile, biological activity was tested for antioxidant activity and antielastase as measured by a microplate reader 96-well spectrophotometry method at specific wavelengths. According to the results, G. dulcis and G. forbesii fruit peel extracts showed positive detection of particular secondary metabolites. TPC and TFC values were 13.98 ± 1.90 mg GAE/g and 10.33 ± 1.90 mg QE/g for G. dulcis and 11.98 ± 2.04 mgGAE/g and 1.96 ± 0.36 mgQE/g for G. forbesii. Metabolite profiling detected some compounds from G. dulcis, including ephedrannin B, hinokiflavone, mahuannin J, and candidate mass C9H12O8, and G. forbesii, including 5-Hydroxy-7,8,2'- trimethoxyflavone, lucialdehyde B, candidate mass C21H39NO4, candidate mass C14H10O6, and candidate mass C14H12O6. Meanwhile, the biological activities (antioxidant and antielastase) were 137.721 μg/mL and 108.893 μg/mL for G. dulcis and 481.948 μg/mL and 250.611 μg/mL for G. forbesii, respectively. Both plants showed different profiles of secondary metabolites and biological activities (antioxidant and antielastase) according to their respective characteristics.

The Comparison Of Bioactive Compounds Between Brewed and Extracted Robusta Coffee From West Lampung

Indonesia is ranked fourth highest in coffee production in the world. One type of coffee export commodity, namely Robusta coffee, is produced from the West Lampung region. Robusta coffee contains various bioactive compounds that act as antioxidants. This study aims to analyze the differences between brewed and extracted robusta coffee related to the bioactive compounds. The method used in this study began with coffee sample preparation, followed by brewing and ethanolic extracting the robusta coffee, measurement of TPC (total phenolic content in gallic acid equivalent), TFC (total flavonoid content in quercetin equivalent), and antioxidant activity using the DPPH method. The results showed that the TPC values were 11.27 mgGAE/g for brewed coffee and 61.98 mgGAE/g for extracted coffee, while the TFC values for brewed coffee were 11.99 mgQE/g and extracted coffee were 18.40 mgQE/g. The highest antioxidant activity value was obtained from extracted robusta coffee with an IC50 89.43 ppm which classified as strong enough antioxidant, while the antioxidant activity of brewed coffee has an IC50 218.74 ppm which classified as moderate antioxidant. TPC and TFC in this study showed a direct proportional relationship with antioxidant activity. The samples with the highest total phenolic and total flavonoid also exhibited the highest antioxidant activity.

Phytochemical screening and antioxidant activity of selected underutilized plants in Nadir Plot Taman Botani, Sri Medan, Johor

This study was conducted to determine phytochemical content and antioxidant activity of selected underutilized plants in the Nadir plot in Taman Botani such as Phyllanthus acidus, Diospyrus dicolour, Flacourtia rukam and Anacardium occidentale. The total phenolic content was analyzed using Folin Ciocalteu and total flavonoid content was analyzed using aluminium chloride. The antioxidant activity was evaluated by DPPH radical scavenging, ABTS radical scavenging and Ferric Reducing Antioxidant Power assay. The results showed that the phenolic content for Flacourtia rukam leaves was the highest with 87.17 ± 0.5890 mg GAE/g, Phyllanthus acidus leaves had the highest total flavonoid content value with 149.83 ± 0.5768 mg RE/g. DPPH, radical scavenging showed that Anacardium occidentale has the lowest IC50 value of 57.9132 ± 15.03802 µg/mL. Therefore, it has the strongest antioxidant potential. However, the results for ABTS radical scavenging showed that Phyllanthus acidus has the lowest IC50 value of 3.7581 ± 5.8748 µg/mL, which has the strongest antioxidant activity. Ferric Reducing Antioxidant Power assay method, Flacourtia rukam shows the highest FRAP value with 9.9336 mM Fe2+ /L. In conclusion utilising Phyllanthus acidus, Diospyrus dicolour, Flacourtia rukam and Anacardium occidentale as sources of phytochemicals could offer opportunities for nutraceutical and functional food applications.

Phenolic Compounds, Free Radical Scavenging Activity and α-Glucosidase Inhibition Properties of Green, Oolong and Black Sacha Inchi Tea Extract

Sacha Inchi leaves may possess antioxidant function which is naturally rich in bioactive ingredients and has been widely processed into herbal teas that has many benefits to human health. According to the global data from the World Health Organization (WHO), there has been a rise in the frequency of diabetes mellitus (DM) among adults. Sacha Inchi tea was prepared using several methods, with green tea not fermented, oolong partially fermented, and black tea completely fermented. The phenolic compounds (total phenolic content (TPC), total flavonoid content (TFC), tannin), free radical scavenging activity (DPPH) and inhibition properties of α-Glucosidase on green, oolong and black Sacha Inchi tea extract were determined. The green Sacha Inchi tea extract displayed the highest TPC and TFC values among the oolong and black Sacha Inchi tea extracts at a concentration of 500µg/mL, with values of 2.10±0.01 µg GAE/mL and 3.23±0.20 µg QE/mL, respectively. Meanwhile, at a concentration of 500µg/mL, Sacha Inchi black tea extract demonstrated strong antioxidant activity by DPPH with radical scavenging activity (%) (89.4±0.45). Furthermore, at a concentration of 15.625 µg/mL, black, oolong, and green tea extracts exhibited stronger inhibitory effects on α-Glucosidase (95%, 95%, 92%, respectively) than acarbose (90%). Therefore, the processing steps involved in tea production impact the phenolic compounds, free radical scavenging activity, and the ability to inhibit α-Glucosidase in green, oolong, and black tea extracts.

Proximate Nutritional Analysis, Phytochemical Screening and Antioxidant Properties of Aqueous Extract of Neptunia oleracea Leaves

Neptunia oleracea also known as water mimosa is widely consumed by people worldwide including Malaysia. This plant was claimed able to treat several diseases such as epileptic convulsion, syphilis, jaundice, and bloody diarrhea. Moreover, it has been reported to possess antimicrobial, antioxidant, and anti-ulcer properties that benefit human health. Hence, this study investigates the content of macronutrients, micronutrients, phytochemical constituents, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant properties in the aqueous leaf extract of this plant. The study found that N. oleracea leaves were possessed with high fiber (52%), moisture (23.33%), fat (5.33%), protein (5.25%), carbohydrate (6.42%), ash (7.67%), and mineral content with a sequence of Potassium > Calcium > Sodium > Phosphorus. A positive result of tannins, steroids, phenols, and flavonoids were detected. High values of TPC and TFC which were 136.19 ± 0.62 mg GAE/g and 829.17 ± 19.09 mg GAE/g of dry weight respectively were obtained. Meanwhile, the hydrogen peroxide scavenging activity of the plant extract produced an IC50 of 70.09 µg/mL. The presence of a high content of polyphenolic compounds may reflect the antioxidant properties of this plant. In conclusion, the aqueous extract of N. oleracea leaves showed the presence of various phytochemical constituents and has a high content of TPC and TFC which may be derived from its nutritional content. Hence, consumption of N. oleracea leaves is useful for human health and disease prevention.

Phaleria macrocarpa (Scheff.) Boerl. (Mahkota Dewa) seed essential oils: Extraction yield, volatile components, antibacterial, and antioxidant activities based on different solvents using Soxhlet extraction

Phaleria macrocarpa (Scheff.) Boerl., locally known as ‘Mahkota Dewa’, is a fruit commonly found in Malaysia. It demonstrates high potential for various biological activities, including antioxidant, anti-inflammatory, antibacterial, and anticancer properties. Nevertheless, there is a lack of research on the effect of essential oil extraction using different solvents on the antibacterial and antioxidant activities of this seed's fruit. This study aims to investigate the extraction yield, volatile components, antibacterial, and antioxidant activities of essential oil extracted from P. macrocarpa seeds using ethyl acetate, hexane, and petroleum ether as solvents. Gas chromatography-mass spectrometry was used to analyse the volatile components, while the antibacterial activity was assessed against Listeria innocua and Serratia marcescens. The antioxidant activity was evaluated using total phenolic content (TPC), total flavonoid content (TFC), and the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Hexane showed the highest extraction yield (51.87 ± 0.21%), followed by petroleum ether (44.40 ± 0.14%) and ethyl acetate (27.08 ± 0.10%). The essential oils extracted with ethyl acetate, hexane, and petroleum ether contained 24, 26, and 21 volatile components, respectively. The major component, 1-(ethenylthio)-octane was found in concentrations ranging from 42.371 to 54.863 ppm, followed by 2,2-dimethyl-5-(3-methyl-2-oxiranyl)cyclohexanone, with concentrations between 30.771 and 40.783 ppm. The essential oil exhibited moderate antibacterial activity, as indicated by the zone of inhibition against L. innocua (8.00 ± 1.30 mm to 11.00 ± 1.40 mm) and S. marcescens (9.00 ± 1.00 mm to 14.00 ± 1.20 mm) compared to the positive control. Additionally, the essential oil demonstrated good antioxidant activity, with TPC, TFC, and DPPH values for hexane (65.56 ± 0.02 mg GAE/g, 4.46 ± 0.17 mg RE/g, 223.78 ± 29.69 μg/mL), ethyl acetate (72.99 ± 0.05 mg GAE/g, 19.47 ± 0.41 mg RE/g, 294.02 ± 12.70 μg/mL), and petroleum ether (70.29 ± 0.07 mg GAE/g, 4.83 ± 0.05 mg RE/g, 803.64 ± 27.76 μg/mL), respectively. Nonetheless, correlation analysis revealed a moderate relationship between DPPH and TFC. The essential oils from P. macrocarpa seeds demonstrates strong natural antibacterial and antioxidant potential, with hexane as the most efficient solvent. Exploring compounds like 1-(ethenylthio)-octane and 2,2-dimethyl-5-(3-methyl-2-oxiranyl)cyclohexanone may reveal medicinal applications and lead to innovative remedies.

Comprehensive LC‐MS/MS phenolic profiling of Arum elongatum plant and bioaccessibility of phenolics in their infusions

AbstractArum elongatum has various bioactive compounds including phenolic acids and flavonoids that may have beneficial effects on human health. The main objectives of this study were to determine the phenolic profile of the A. elongatum plant together with the total phenolic (TPC), total flavonoid contents (TFC), and total antioxidant capacities of A. elongatum infusions throughout gastrointestinal digestion. The samples used in the present study were obtained from two cities (C1 and C2) in Türkiye. According to the results, while the primary compounds found in sample C1 were vanillic acid (51.29 ± 2.61 ng/mg), p‐coumaric acid (48.36 ± 2.84 ng/mg) and O‐coumaric acid (156.02 ± 0.67 ng/mg); chlorogenic acid (50.63 ± 0.65 ng/mg), scutellarin (144.34 ± 0.74 ng/mg), and O‐coumaric acid (53.34 ± 0.97 ng/mg) were the major compounds in C2 sample showing the differences between different locations. In addition to these, although both TPC and TFC values for C2 infusion (2960 ± 104 mg GAE/100 g and 397 ± 50 mg CE/100 g, respectively) were found to be higher than the infusion of sample C1, there were no significant differences between the TPC and TFC results after intestinal digestion (p > 0.05). Besides, TPC of the bioaccessible fractions of these two samples didn't show a significant difference (p > 0.05), whereas C1 infusion (202 ± 21%) presented a higher value than the C2 infusion (143 ± 12%) for their bioaccessible TFC value. Our results indicated that A. elongatum infusion may be a potential herbal tea due to its rich phenolic content, making it a suitable substitute for widely used herbal teas.

Insight into Bioactive Compounds, Antioxidant and Anti-Diabetic Properties of Rosehip (Rosa canina L.)-Based Tisanes with Addition of Hibiscus Flowers (Hibiscus sabdariffa L.) and Saffron (Crocus sativus L.)

Tisane is a fruit or herbal infusion, commonly referred to as herbal tea. These products are consumed as part of a balanced diet, which is closely related to the trend of a healthier lifestyle. In this work, tisanes prepared from rosehip (R), and herbal mixtures containing rosehip/hibiscus flowers (R/H) and rosehip/hibiscus flowers/saffron (R/H/S) were studied. Rosehip was dried by the convective drying method at 40, 50 and 60 °C. Total phenolic content (TPC), total flavonoid content (TFC), total flavonol content (TFlC), total anthocyanin content (TAC), antioxidant properties (DPPH∙ and ABTS∙+ assays) and in vitro inhibitory potential toward α-amylase of tisanes were examined. The highest TPC (based on dry weight (dw)) was measured in tisane obtained from rosehip dried at 60 °C (37.84 mg GAE/g dw). Tisanes prepared from a R/H/S mixture had the highest values of TFC (4.66–6.13 mg QUE/g dw), TFlC (2.67–3.98 mg QUE/g dw) and TAC (1.35–2.27 mg Cy 3-glc/g dw). The highest DPPH∙ scavenging activity (53.42 mg TE/g dw) was measured in rosehip (dried at 60 °C) tisane, whereas tisane prepared from a rosehip (dried at 60 °C)/hibiscus mixture expressed the best ABTS∙+ scavenging activity (107.44 mg TE/g dw). All tisane samples expressed high inhibitory potential toward α-amylase, with the highest activity of 85.03% and 89.90%, measured for tisanes prepared from rosehip/hibiscus flowers mixture (rosehip dried at 50 and 60 °C, respectively).

Effect of Microwave and Conventional Heat Treatment on Total Phenolic Compounds, HPLC Phenolic Profile, and Antioxidant Activity of Leptadenia pyrotechnica (Forssk.) Decne Stem

Leptadenia pyrotechnica is considered a wild herb used to enhance the palatability of food, particularly in the Gulf region. The effect of microwave (5, 8, and 10 min at 900 W) and hot-air heating (60, 120, and 180 min at 100 °C) on the phenolic compounds and antioxidants of L. pyrotechnica stems was investigated. The results showed that microwave heating gave high values of the total phenolic content (TPC), total flavonoid content (TFC), and antioxidant properties, while the control sample was inferior in all these attributes. Moreover, microwave heating, particularly for 8 min, produced the highest TPC, TFC, and DPPH values (significant at p < 0.05) and reduced power in the L. pyrotechnica stem. However, prolonging the heating time caused adverse effects on the bioactive potential of the samples. The HPLC analysis indicates that both processes caused a significant increment in the phenolic compounds of the sample. Tannic acid, vanillin, and acetyl salicylic acid were found to be higher in the microwaved-treated samples than in those heated with hot air. The tannic acid was found to be high after microwave heating for 8 min at 116.06 mg/100 g, while the higher value of acetylsalicylic acid 119.08 mg/100 g was observed after microwave heating for 5 min. The partial least regression (PLS) validation model revealed that microwave heating, particularly at an 8 min application time, offered better results, and owing to its short processing time, which might be adopted for heating the L. pyrotechnica stems in the food industry, and it can be useful for preparing functional foods.

Phytochemical Assessment, Antioxidant Activity, and in vitro Wound Healing Potential of Polygonum minus Huds

The increasing prevalence of chronic wounds, associated with aging, obesity, and diabetes, is compounded by bacterial resistance and adverse effects associated with commercial wound care products. Therefore, treatment modalities to accelerate the healing process are constantly being sought. This study aimed to investigate the phytochemical composition, antioxidant, and wound healing potential of the aqueous extract derived from the stems and leaves of Polygonum minus. The extract was subjected to phytochemical evaluation to assess the diversity of secondary metabolites. The total phenolic content (TPC) and total flavonoid content (TFC) were measured using the Folin-Ciocalteu colorimetric and aluminium chloride methods, respectively. The antioxidant activity was determined using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and ferric-reducing antioxidant power (FRAP) assays. The wound healing effects were evaluated using proliferation and migration assays on human epidermal keratinocyte (HaCaT) cells. The phytochemical evaluation of the aqueous extract revealed the presence of flavonoids, terpenoids, alkaloids, saponins, tannins, steroids, and cardiac glycosides. Furthermore, the extract exhibited high TPC (137.74 ± 0.75 µg/mL GAE) and TFC (177.08 ± 3.16 µg/mL QE) values, as well as radical scavenging activity at 79.50% in the DPPH assay and a FRAP value of 1485.67 ± 0.05 µM/g Fe2+. At the lowest concentration of 7.81 μg/mL, the extract significantly stimulated cell proliferation and migration within 24 hours of treatment. The stimulation of cell migration was comparable with that of allantoin, which was used as a positive control. This study indicated that the P. minus aqueous extract contains a high concentration of phenolic compounds, which could contribute significantly to its antioxidant activity and promote the proliferation and migration of keratinocytes. The findings suggest that the extract may merit further investigation for potential applications in topical therapy related to wound healing.

Phytochemical Screening and Antioxidant Activities of Geniotrigona thoracica Propolis Extracts Derived from Different Locations in Malaysia

Propolis, a natural resinous substance secreted by bees, has garnered considerable interest due to its diverse bioactive compounds and potential health benefits. Nevertheless, the phytochemical composition of propolis exhibits significant variation, influenced by multiple factors including geographical region, and botanical origin. These determinants exert profound effects on the distinctive properties and biological diversities of propolis. This study aimed to investigate the phytochemical composition and antioxidant activities of Geniotrigona thoracica propolis extracts collected from three apiary sites, designated as apiary A, apiary B, and apiary C, located in different regions within Selangor. The ethanolic extracts of propolis were prepared using 70% of ethanol and subjected to phytochemical screening to identify the presence of flavonoids, terpenoids, alkaloids, saponins, tannins, steroids, and cardiac glycosides, whilst the total phenolic content (TPC) and total flavonoid content (TFC) were measured using the Folin-Ciocalteu colorimetric and aluminium chloride methods, respectively. Additionally, the antioxidant activities of the propolis extracts were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric-reducing antioxidant power (FRAP) assays. The phytochemical screening revealed the presence of flavonoids, terpenoids, alkaloids, saponins, tannins, steroids, and cardiac glycosides in all propolis extracts. The propolis from apiary A exhibited significantly higher TPC (302.21 ± 0.11 mg/mL GAE) and TFC values (99.08 ± 0.03 mg/mL QE) compared to apiary B and C. The results also indicated that propolis from apiary A possessed significantly higher antioxidant activities, with IC₅₀ value of DPPH at 25.27 μg/mL and FRAP value of 727.53 ± 0.09 μM Fe²+, in comparison to apiary B and C. A strong correlation was observed between TPC, TFC, and IC₅₀ of DPPH. This study highlights significant variations in the phytochemical compositions and antioxidant activities of propolis samples collected from different geographical and botanical sources. Further investigation is in progress to identify the specific phytochemical constituents responsible for these variations.