Identification Of Phenolic Compounds Research Articles

Fractionation and Identification of Phenolic Compounds from Ethylacetate Fraction of Ageratum Conyzoides Methanolic Leaf Extract

Natural phenols are significant functional substances that are commonly present in plants and provide advantages for human health. Phenolics can be utilized for a variety of therapeutic applications, such as antioxidant, anti-inflammatory, antidiabetic, and antibacterial activities. This work aimed to fractionate and identify the phenolic compounds present in ethylacetate fractions of the methanolic leaf extracts of A. conyzoides. Fractionation and purification of the ethylacetate fraction using column chromatography and TLC, followed by FTIR and LC-MS for identification, were employed in this work. While the FTIR spectroscopy was used to identify the fractions with –OH functional group, LCMS was used to identify the phenolics. After fractionation and purification, six ethylacetate samples were obtained, each with different Rf values, of which three showed a pronounced presence of OH functional groups in phenolics. Subsequently, four phenolic compounds were identified: furocoumaric acid, liquiritin, isorhamnetin, and syringin. This research has demonstrated that ethylacetate fraction of A. conyzoides methanol leaf extract is a good source of the phenolic compounds: Furocoumaric acid, Liquiritin, Isorhamnetin, and syringin.

Leaves of Allium cepa and Xylopia aethiopica fruits as potent sources of natural antioxidant for stabilization of viscera FISH oil during accelerated storage

The present study investigated the antioxidant activities of methanolic extracts of two local plants and their capacities to preserve the quality of viscera fish oil during storage. The total phenolic, total flavonoids and tannins contents were analyzed by colorimetry, the preliminary antioxidant tests done and identification of phenolic compounds by HPLC-DAD (Diode Array Detector) and ESI-MS. After these evaluation, the plant extracts were added in viscera fish oil at concentration 200–1000 ppm. The oxidative stability of these fish oil samples was evaluated by measuring their qualities indices during 16 days at 70 °C. Here, oils were collected at the day 0, 4, 8, 12 and 16. The total phenolic, flavonoids and tannins contents in Xylopia aethiopica fruits were 15.62 g Eq acid galic/100g of dry extract, 10.85 mg Eq quercetin/100g of dry extract and 0.79 mg Eq cathechin/100 mg of dry extract. Those of Allium cepa leaves were 6.85 g Eq acid galic/100g of dry extract, 1.50 mg Eq quercetin/100g of dry extract and 0.11 mg Eq cathechin/100 mg of dry extract. All the methanolic extracts exhibited antioxidant activity. The results recorded after FRAP assay revealed the low IC50 (12.87 mg/mL) in Allium cepa extract compared to that of Xylopia aethiopica extract (44.90 mg/mL). These local plants contain many classes of phenolic compounds and they can be used in oil and fat industries as alternative of synthetic antioxidants.

Phytochemical Analysis and Antioxidant Effects of Prunella vulgaris in Experimental Acute Inflammation.

Prunella vulgaris (PV) is one of the most commonly used nutraceuticals as it has been proven to have anti-inflammatory and antioxidant properties. The aim of this study was to evaluate the phytochemical composition of PV and its in vivo antioxidant properties. A phytochemical analysis measuring the total phenolic content (TPC), the identification of phenolic compounds by HPLC-DAD-ESI, and the evaluation of the in vitro antioxidant activity by the DPPH assay of the extract were performed. The antioxidant effects on inflammation induced by turpentine oil were experimentally tested in rats. Seven groups with six animals each were used: a control group, the experimental inflammation treatment group, the experimental inflammation and diclofenac sodium (DS) treatment group, and four groups with their inflammation treated using different dilutions of the extract. Serum redox balance was assessed based on total oxidative status (TOS), nitric oxide (NO), malondialdehyde (MDA), total antioxidant capacity (TAC), total thiols, and an oxidative stress index (OSI) contents. The TPC was 0.28 mg gallic acid equivalents (GAE)/mL extract, while specific representatives were represented by caffeic acid, p-coumaric acid, dihydroxybenzoic acid, gentisic acid, protocatechuic acid, rosmarinic acid, vanillic acid, apigenin-glucuronide, hesperidin, kaempferol-glucuronide. The highest amount (370.45 μg/mL) was reported for hesperidin, which is a phenolic compound belonging to the flavanone subclass. The antioxidant activity of the extracts, determined using the DPPH assay, was 27.52 mmol Trolox/mL extract. The PV treatment reduced the oxidative stress by lowering the TOS, OSI, NO, and MDA and by increasing the TAC and thiols. In acute inflammation, treatment with the PV extract reduced oxidative stress, with lower concentrations being more efficient and having a better effect than DS.

LC-MS/MS-QTOF Screening and Identification of Phenolic compounds from Ethyl Acetate Fraction of Madhuca longifolia Leaves

Natural products, particularly those derived from plants and microbes, offer an endless supply of unique compounds that can be converted into new pharmaceuticals. Due to their potential health benefits, bioactive components from herbs, particularly phenolics, have recently attracted a lot of interest. One of the multi-use forest tree species, Madhuca longifoliaJ. Koenig. (mahua), is found throughout much of South Asia and offers locals a source of food, fuel, fodder, and other non-timber forest products (NTFPs) in addition to timber. Almost all of this tree's components exhibit its therapeutic qualities.Mahua's phytochemical analysis reveals that it contains high levels of vitamins, alkaloids, sugar, glycosides, proteins, steroids, tannins, flavonoids, saponins, terpenoids, and phenolic compounds. These compounds are responsible for a variety of pharmacological properties, including anti-inflammatory, antioxidant, analgesic, antihyperglycemic, spasmolytic, hepatoprotective, anticonvulsant, anticancer, results of the High-Resolution Liquid Chromatography Mass Spectroscopy (HR-LCMS) analysis showed that plant extracts included a number of pharmaceutically significant chemicals. By comparing the weights and fragmentation patterns of the twenty-four (24) phenolic compounds in this work with those of published libraries, the LC-MS/MS method was used to screen and confirm them. The findings of this research support the usage of this plant as a source of bioactives and the beneficial effects of these compounds on human health.

Identification of phenolic compounds from fermented Moringa oleifera Lam. leaf supplemented with Fuzhuan brick tea and their volatile composition and anti-obesity activity.

As a nutritious plant with valuable potential, the Moringa oleifera Lam. (MOL) leaf addition on Fuzhuan brick tea (FBT) for the co-fermentation (MOL-FBT) was an industry innovation and a new route to make full use of MOL leaf. After optimization of the extraction conditions, the best conditions for the polyphenols extraction method from MOL-FBT (MFP) were 60°C for 40min (1:80, V/W) using response surface methodology. A total of 30 phenolics were identified and quantified. Most of the polyphenols were increased after adding MOL leaf for co-fermentation compared to FBT polyphenols. In particular, caffeic acids were found only in MFP. Moreover, the MFP received high value in taste, aroma, and color. In total, 62 volatile flavor compounds, consisting of 3 acids, 5 alcohols, 15 aldehydes, 4 esters, 20 hydrocarbons, 10 ketones, and 5 others, were identified in MFP. In addition, MFP inhibited 3T3-L1 preadipocyte differentiation in a dose-dependent manner and decreased lipid accumulation via the peroxisome proliferator-activated receptor gamma (PPARγ)/CCAAT/enhancer binding protein alpha (CEBPα)/cluster of differentiation 36 (CD36) axis and induced a brown adipocyte-like phenotype. In vivo experiments were further conducted to confirm the in vitro results. MFP regulated lipid accumulation, glucose/insulin tolerance, improved liver and kidney function, and inhibited the secretion of pro-inflammatory factors by the PPARγ/CEBPα/CD36 axis and alleviated inflammation in high fat and high fructose diet-induced obese mice. In summary, MFP possesses high-quality properties and anti-obesity effects, as well as the great potential to be used as a novel functional food product.

Bioactive Potential of Olive Mill Waste Obtained from Cultivars Grown in the Island of Malta.

This study explores the bioactive potential of olive mill waste derived from cultivars grown in the Maltese Islands through various analytical approaches. Cell culture, cell staining, allelopathic assays, shrimp brine lethality assays, and HPLC analysis were conducted to assess the efficacy and bioactivity of the extracts using different treatments, including methanolic extraction, acid, and alkaline hydrolysis. Notably, the results from cell lines revealed that NB4r2 cells exhibited high susceptibility to the tested extracts, with the lowest IC50 recorded after 72 h of exposure. Notably, the 'Bajda' cultivar displayed the most effectiveness, particularly with acid hydrolysis. In allelopathic assays, higher concentrations of 'Malti', 'Bidni', and 'Bajda' extracts significantly inhibited lettuce seed germination. Similarly, in the brine shrimp lethality assay, higher concentrations led to increased mortality rates of Artemia salina, though rates decreased at lower concentrations. The identification of phenolic compounds found in olive mill waste was conducted using high-performance liquid chromatography (HPLC) with the use of internal standards. The identification revealed a variety of compounds, with 3-hydroxytyrosol and oleacein being present in high abundance in nearly all hydrolyzed and methanolic extracts, whereas gallic acid was found to be the least abundant. These findings highlight the rich bioactive potential of olive mill waste and provide insights into its applications in pharmaceuticals, nutraceuticals, and agriculture, emphasizing the importance of further research to fully exploit these valuable resources.

Identification of Phenolic Compounds from Vietnamese Artichoke (Cynara scolymus L.) Leaf and Their Antioxidant Activities

Identification of Phenolic Compounds from Vietnamese Artichoke (Cynara scolymus L.) Leaf and Their Antioxidant Activities

Green synthesis of magnesium oxide nanoparticles using endophytic fungal strain to improve the growth, metabolic activities, yield traits, and phenolic compounds content of Nigella sativa L.

Abstract Endophytic fungus Penicillium crustosum EP-1 was used to create spherical shape magnesium oxide nanoparticles (MgO-NPs). The MgO-NPs possess a crystalline structure with sizes of 8–35 nm. The weight percentages of Mg and O were 42.44% and 30.13%, respectively, as shown in energy-dispersive X-ray analysis. In addition, analysis involving dynamic light scattering indicated the uniformity of MgO-NPs within the colloidal solution. These NPs displayed a polydispersity index of 0.341 and held a surface charge of −29.7 mV. A field experimental was carried out to assess the outcome of foliar spraying of MgO-NPs at 5, 10, and 20 ppm on the growth, yield, and metabolic activities of Nigella sativa L. Our results indicated that MgO-NPs significantly enhanced various growth parameters, including chlorophyll content (both a and b), total carotenoids, carbohydrate and protein levels in both shoots and seeds, as well as free proline concentration, compared to the control plants at both 55 and 75 days after planting. In addition, all yield traits were markedly increased. Moreover, high-performance liquid chromatography is employed for the identification of phenolic compounds within the seeds. Data indicated that sex phenolic acids, two phenols, and five flavonoids were present with high concentrations due to MgO-NPs treatment as opposed to untreated plants.

Isolation and identification of phenolic compounds from Eugenia caryophyllus and study on its biological effect against Macrophomina phaseolina

Clove is one of the oldest and most famous spices. Its seeds resemble nails. It is used in medicinal fields, but its fungicidal activity is unknown. The aim of the study was to test the inhibitory activity of phenolic extracts of cloves against the pathogenic fungus Macrophomina phaseolina. The research was conducted under laboratory conditions to test the inhibitory ability of Eugenia caryophyllus phenolic extracts on the fungus M. phaseolina, which was partially diagnosed on strawberry plants based on Polymerase chain reaction (PCR) technique, in addition to its morphological and microscopic characteristics. The active compounds present The active compounds (Chlorogenic acid, Qurcetine, Gallic acid, Apigenin, Caffeic acid, Ferulic acid, Kaempferol, Rutin, Catechine) present in the extract of Industrial Methylated Spirit (IMS) separated from cloves were determined using High-performance liquid chromatography (HPLC). and active compounds of IMS phenols) Qurcetine, Apigenin, Ferulic acid, Kaempferol. (The inhibitory effect of phenols extracted from E. caryophyllus against M. phaseolina was tested. The results showed that the acetone extract and acetone phenols, which were used at concentrations of 10 and 15 mg/ml in PDA medium, had a significant effect on the growth of the fungus by 100%, as these fungi failed to grow. Formation of spores on Peptone dextrose medium (PDA) medium. While the percentage of inhibition of acetone phenols was 25% at a concentration of 5 mg/ml. As for the IMS extract and IMS phenols, it had a significant effect on the growth of the fungus at all concentrations used, but with different inhibition ratios, which increased directly with increasing concentration of the extract.

Analysis and identification of phenolic compounds with antiproliferative activity from Chinese olive (Canarium album L.) fruit extract by HPLC-DAD-SPE-TT-NMR.

Chinese olives (Canarium album L.) are rich in phenolic compounds, exhibiting a broad spectrum of potential clinical applications. This study is the first report on the isolation and elucidation of bioactive compounds with high antiproliferative activity from the ethyl acetate fraction of a Chinese olive fruit methanolic extract (CO-EtOAc). We used the WST-1 assay to determine which subfractions of CO-EtOAc had significant antiproliferative activity using the murine colon cancer cell line CT26. Subsequently, the functional compounds were characterized by the hyphenated technique and high-performance liquid chromatography-diode array detector-solid phase extraction-transfer tube-nuclear magnetic resonance (HPLC-DAD-SPE-TT-NMR). Thirteen phenolic constituents were identified from the antiproliferation-enhancing subfractions of CO-EtOAc, including two new compounds, 2,4-didehydrochebulic acid 1,7-dimethyl ester (5) and 1-hydroxybrevifolin (7), which were further purified and found to exhibit marked antiproliferative activity. Chebulic acid dimethyl ester (2), which was isolated from C. album for the first time, also possessed antiproliferative activity.

Smartphone-assisted nanozyme sensor array constructed based on reaction kinetics for the discrimination and identification of phenolic compounds

Although the research on nanozymes has attracted widespread attention in recent years, the development of highly active and multifunctional nanozymes remains a challenge. Here, a bifunctional AMP-Cu nanozyme with laccase- and catecholase-like activities was successfully prepared at room temperature with Cu2+ as the metal ion and adenosine-5′-monophosphate (AMP) as the ligand molecule.Based on the excellent catalytic performance of AMP-Cu, a three-channel colorimetric sensor array was constructed using reaction kinetics as the sensing unit to achieve high-throughput detection and identification of six common phenolic compounds at low concentrations. This strategy simplifies the construction of sensor array and demonstrates the capacity to obtain multidimensional data from a single material. Finally, with the assistance of smartphones and homemade dark boxes, a portable on-site detection method for phenolic compounds was developed. This work would contribute to the development of portable sensors and the highly efficient identification of phenolic compounds in complex samples.

Construction of a colorimetric sensor array for the identification of phenolic compounds by the laccase-like activity of N-doped manganese oxide

Phenolic compounds, widely distributed in nature, encompass a diverse array of bioactive and antioxidant properties. The detection of different phenolic compound types holds paramount importance in elucidating their bioactivity and health effects, ensuring the quality and safety of food and drugs. Consequently, the development of simple, rapid, and cost-effective colorimetric sensing arrays capable of simultaneous phenolic compound detection has emerged as a prominent research pursuit. In this study, we present a one-step hydrothermal synthesis of N-doped MnO2 nanoflowers (NMF). NMF possess an extensive specific surface area and abundant oxygen vacancies, effectively mimicking the activity of natural laccase. Leveraging this laccase-like activity, NMF demonstrates the ability to catalyze various phenolic compounds, generating distinctive fingerprint signals. Notably, the developed colorimetric sensing array exhibits remarkable efficacy in effectively identifying and differentiating phenolic compounds within complex mixtures. Furthermore, the NMF colorimetric sensing array demonstrates successful identification of phenolic compounds in diverse environments, including food and urine samples. Overall, this study provides new insights into the design of transition metal materials for the simulation of laccase and colorimetric sensing arrays. It provides a promising avenue for the development of advanced detection platforms for phenolic compounds.

In Silico Analysis of Phenolic Compounds from Ceriops decandra Griff. Leaves and Molecular Interaction as Anti Diabetes

α-amylase and α-glucosidase in the gastrointestinal tract have an important role in the hydrolysis α-1,4 and α-1,6 glycosidic chain of starch, respectively. Inhibition of both enzyme activities becomes one of the strategies to control diabetes. However, commercial drugs such as antidiabetics have adverse effects such as gastrointestinal problems. Therefore, exploring functional food, especially from marine natural products as antidiabetic agents, is potential. In particular, Ceriops sp. was reported to contain bioactive compounds with antidiabetic properties, but its mechanism to treat diabetes has not been proved. The potency of phenolic compounds of C. decandra leaves as α-amylase and α-glucosidase inhibitors were examined in this research by implementing the molecular docking analysis in silico. Three steps of analysis were carried out in this study, including extraction from C. decandra leaves with different polarity solvents, identification of phenolic compounds using LC-HRMS, and molecular docking analysis of phenolic compounds identified from C. decandra leaves. This study revealed that quercetin, rutin, epicatechin, isorhamnetin, caffeic acid, and ferulic acid were identified from C. decandra leaves. According to the drug-likeness and toxicity analysis, the presented compounds in C. decandra leaves had high potential pharmacological properties. Furthermore, molecular interaction analysis exhibited phenolic compounds extracted with ethyl acetate, such as quercetin and epicatechin, and with methanolic extracts, such as quercetin, rutin, epicatechin, and isorhamnetin, were more effective as α-amylase and α-glucosidase inhibitors than from caffeic acid and ferulic acid. Among the phenolic compounds of C. decandra leaves, rutin and quercetin were predicted to be the potential α-glucosidase inhibitors.

Byrsonima sericea Ethanol Extract Protected PC12 Cells from the Oxidative Stress and Apoptosis Induced by 6-Hydroxydopamine.

Parkinson's disease is characterized by the progressive loss of dopaminergic neurons in the nigrostriatal pathway and oxidative stress is one of the main mechanisms that lead to neuronal death in this disease. Previous studies have shown antioxidant activity from the leaves of Byrsonima sericea, a plant of the Malpighiaceae family. This study aimed to evaluate the cytoprotective activity of the B. sericea ethanolic extract (BSEE) against the cytotoxicity induced by 6-hydroxydopamine (6-OHDA) in PC12 cells, an in vitro model of parkinsonism. The identification of phenolic compounds in the extract by HPLC-DAD revealed the presence of geraniin, rutin, isoquercetin, kaempferol 3-O-β-rutinoside, and quercetin. The BSEE (75-300µg/mL) protected PC12 cells from toxicity induced by 6-OHDA (25µg/mL), protected cell membrane integrity and showed antioxidant activity. BSEE was able to decrease nitrite levels, glutathione depletion, and protect cells from 6-OHDA-induced apoptosis. Thus, we suggest that the BSEE can be explored as a possible cytoprotective agent for Parkinson's disease due to its high antioxidant capacity and anti-apoptotic action.

Identification of phenolic compounds from inflorescences of non-psychoactive Cannabis sativa L. by UHPLC-HRMS and in vitro assessment of the antiproliferative activity against colorectal cancer

Phenolic compounds from Cannabis sativa L. (Cannabaceae family), in particular cannflavins, are known to possess several biological properties. However, their antiproliferative activity, being of great interest from a medicinal chemistry point of view, has not been deeply investigated so far in the literature. In the light of this, the aim of this study was to obtain an enriched fraction of polyphenols (namely PEF) from inflorescences of a non-psychoactive C. sativa (hemp) variety and to evaluate its antiproliferative activity against cancer cells, capitalizing on a new and selective extraction method for hemp polyphenols, followed by preparative flash column chromatography. Untargeted metabolomics, using a new method based on ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC-HRMS), was applied here for the first time to fully characterize PEF. Then, the main phenolic compounds were quantified by HPLC-UV. The antiproliferative activity of PEF and of the isolated compounds was assessed in vitro for the first time against Caco-2 and SW480 human colon adenocarcinoma cell lines providing promising IC50 values, in comparison with the reference drug used in therapy for this cancer type. Based on these results, PEF can be considered as a new highly potential therapeutic product to be further investigated against colorectal cancer, thanks to the possible synergistic interaction of its compounds.

Antioxidant Capacity of Polar and Non-Polar Extracts of Four African Green Leafy Vegetables and Correlation with Polyphenol and Carotenoid Contents.

In sub-Saharan Africa, chronic malnutrition is often associated with intestinal inflammation and oxidative stress. African green leafy vegetables (GLVs), commonly consumed by these populations and rich in bioactive compounds, may improve the antioxidant status. The aim of this study was to measure the antioxidant capacity using complementary assays (DPPH, FRAP, ABTS, ORAC and NO scavenging) in polar and non-polar leaf extracts of four African GLVs, cassava (Manihot esculenta), roselle (Hibiscus sabdariffa), jute mallow (Corchorus olitorius), and amaranth (Amaranthus spp.), with spinach (Spinacia oleracea) chosen as a reference. Their antioxidant capacity was correlated with their total polyphenol (TPC), flavonoid (TFC), condensed tannin, lutein, and β-carotene contents. Identification of phenolic compounds by UHPLC-DAD-MS/MS revealed the presence of three main classes of compound: flavonols, flavones, and hydroxycinnamic acids. Cassava and roselle leaves presented significantly higher TPC and TFC than amaranth, jute mallow, and spinach. They also exhibited the highest antioxidant capacity, even higher than that of spinach, which is known for its important antioxidant effect. The antioxidant capacity was 2 to 18 times higher in polar than non-polar extracts, and was more strongly correlated with TPC and TFC (R > 0.8) than with β-carotene and lutein contents. These findings provide new data especially for cassava and roselle leaves, for which studies are scarce, suggesting an appreciable antioxidant capacity compared with other leafy vegetables.

Enhancement of Antioxidant Properties of the Medicinal Plant, Costus Pictus by Optimization of its Drying and Extraction Criteria.

Antioxidants act as major protective factors against different infections and diseases. The search for natural antioxidants has gained significant momentum due to its associated health benefits. It prompted the investigation of the antioxidant properties of widely recognized medicinal plants, considering their prominent role in conventional medicine. The incorporation of natural antioxidants derived from medicinal plants into food products has the potential to enhance their health benefits. The present investigation is the first study on the optimization of drying and extraction techniques in Costus pictus leaves. C. pictus leaves were dried under varying conditions (40, 50 and 60°C) and dried powders were subjected to various solvents, namely water, ethanol, methanol and ethyl acetate. The leaves dried at 60°C and treated with ethanol showed improved activities and were subsequently selected for further extraction. Among the various extraction methods, ultrasound-assisted extraction demonstrated superior antioxidant properties and increased phytochemical contents, making it the optimal technique for our study. Fourier transform infrared spectroscopy (FTIR) reports also substantiated these quantitative results. The extraction process played a significant role in enhancing the desirable attributes and properties of the leaf extracts, surpassing the results obtained from both dried and fresh leaves. The application of liquid chromatography-mass spectrometry (LC-MS) analysis to the leaf extracts facilitated the identification of phenolic compounds and flavonoids, presenting a comprehensive insight into the composition of the extract. Exploration of antioxidant properties, phenolic compounds and flavonoids would validate the benefits and expand the applications of C. pictus in functional foods and nutraceuticals.

Study of the Biological Activity and Phenolic Content of the Ethanol Extract of Phyllogonium viride Brid. (Phyllogoniaceae, Bryophyta).

The present study aimed to examine the phenolic content and evaluate the antimicrobial and antioxidant potential of ethanol extracts from the moss species Phyllogonium viride Brid. on the pathogenic bacteria Salmonella enterica serovar enteritidis, Staphylococcus aureus, Listeria monocytogenes and Escherichia coli, and the pathogenic fungi Candida albicans and Cryptococcus neoformans. The antimicrobial activity was determined from Minimum Inhibitory Concentration (MIC) Minimum Bactericidal Concentration (MBC) and Minimum Fungicidal Concentration (MFC). Antioxidant activity was determined by the DPPH method. Folin-Denis reagent was used for the content of total phenolics and flavonoids and HPLC-DAD for identification of phenolic compounds. The results showed that bacteriostatic and bactericidal activities occurred at concentrations ranging from 9.76 μg/mL-78.13 μg/mL among all evaluated microorganisms. These values, considering the criteria used, suggest the P. viride extract as a potent antimicrobial. For antioxidant activity, P. viride extract was considered weak. Analysis of the phenolic content showed a wide range of compounds, with Kaempferol (0.41 mg/g) being the major compound, followed by t-cinnamic acid and caffeic acid (0.17 mg/g). Although P. viride is a species of moss not yet referenced in scientific publications of biotechnological interest, it has shown promising potential for further studies and possible application as an antimicrobial of natural origin.

Impact and Optimization of the Conditions of Extraction of Phenolic Compounds and Antioxidant Activity of Olive Leaves (Moroccan picholine) Using Response Surface Methodology

The Moroccan picholine tree’s leaves contain phenolic compounds that benefit human health. However, the amount and type of these compounds can vary based on factors such as the extraction method and conditions. This study aimed to improve phenolic compounds’ extraction while minimising harmful chemicals’ use. It has been found that using ethanol as a solvent with ultrasonic extraction is the most effective and environmentally friendly technique. Several parameters, such as the extraction time, solid/solvent ratio, and ethanol concentration as independent variables, were evaluated using a surface response method (RSM) based on the Box–Behnken design (BBD) to optimize the extraction conditions. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis and also examined using the appropriate statistical methods. In optimal conditions, the ultrasonic time, the ratio (solvent/solid) and the concentration (ethanol/water), the content of total polyphenols (TPC), total flavonoids (TFC), and antioxidant activity (by DPPH, ABTS, FRAP) were, respectively, 74.45 ± 1.22 mg EAG/g DM, 17.08 ± 1.85 mg EC/g DM, 83.45 ± 0.89% 82.85 ± 1.52%, and 85.01 ± 2.35%. The identification of phenolic compounds by chromatography coupled with mass spectrum (HPLC-MS) under optimal conditions with two successive extractions showed the presence of hydroxytyrosol, catechin, caffeic acid, vanillin, naringin, oleuropein, quercetin, and kaempferol at high concentrations.

Isolation and Identification of Phenolic Compounds from Ebony Plant Leaves (Diospyros celebica Bakh.)

Isolation of phenolic compounds from Ebony plant leaves (Diospyros celebica Bakh .) was done by maceration technique with methanol solvent. The concentrated extract of methanol dissolved with distilled water and partition was extracted with ethyl acetate. The concentrated ethyl acetate extract dissolved with methanol solvent and partitioned with n-hexane. Then Thin layer chromatography was analyzed before column chromatography, and the eluent suitable for separation is chloroform: methanol 90:10, 80:20, 70:30,60:40,50:50 (v/v) as mobile phase. The compounds were purified with a thin layer preparative and crystallization yielding yellow paste weighing 7.5 mg with Rf = 0.45. The test purity of compounds is done by thin layer chromatography showing a single spot with eluent chloroform: ethyl acetate (50:50) v/v and n-hexane: ethyl acetate ( 80:20) v/v. The following compound was further indicated by Ultraviolet-Visible Spectrophotometer (UV-Vis), Fourier Transform Infra Red Spectrophotometer (FT-IR), and Proton Nuclear Magnetic Resonancy Spectrophotometer (1H-NMR) was estimated as a phenolic methyl gallate, phenolic acid.