Total Phenolic Content, Flavonoid Content and Antioxidant Potential of Wild Vegetables from Western Nepal

Phytochemicals and In Vitro Bioactivities of Aqueous Ethanolic Extracts from Common Vegetables in Thai Food

Non-communicable diseases (NCDs) are the leading global cause of death. The World Health Organization (WHO) has endorsed the consumption of fruits and vegetables because they are rich in phytochemicals that sustainably ameliorate the occurrence of NCDs. Thai food contains many spices and vegetables with recognized health benefits. Quality control of plant samples encountered a bottleneck in the field and comparative studies of plant control origins including species or cultivar identification, growing area and appropriate harvesting time are limited. To address this issue, all plant samples used in this study were cultivated and controlled by the Department of Agriculture, Ministry of Agriculture and Cooperatives, Thailand. The samples were phytochemically screened and determined their health-promoting bioactivities via antioxidant activities and inhibition of NCD-related enzymes including lipase (obesity), α-amylase and α-glucosidase (diabetes), angiotensin-converting enzyme (hypertension), as well as acetylcholinesterase, butyrylcholinesterase and β-secretase (Alzheimer’s disease). The non-enzymatic reaction toward glycation was also evaluated. The results showed that Senegalia pennata subsp. insuavis (Lace) Maslin, Seigler & Ebinger, Citrus hystrix DC. and Solanum melongena ‘Kermit’ extracts exhibited high antioxidant activities. Moreover, Citrus hystrix DC. extract was a potent inhibitor against lipase, angiotensin-converting enzyme and butyrylcholinesterase, while Coriandrum sativum L. and Psophocarpus tetragonolobus (L.) DC. were potent anti-diabetic agents and Senegalia pennata subsp. insuavis (Lace) Maslin, and Seigler & Ebinger was a potent anti-glycation agent. Our data provide a comparative analysis of ten vegetables to encourage healthy food consumption and development to control NCDs in Thailand in the future.

How to express the antioxidant properties of substances properly?

Oxidative stress, associated with an imbalance between the oxidants (reactive oxygen species) and the antioxidants in the body, contributes to the development of many diseases. The body’s fight against reactive oxygen species is supported by antioxidants. Nowadays, there are too many analytical methods, but there is no one universal technique for assessing antioxidant properties. Moreover, the applied different ways of expressing the results lead to their incompatibility and unreasonable interpretation. The paper is a literature review concerning the most frequent ways of antioxidant activities expression and for an easy and universal method of the obtained results discussion. This paper is an attempt to point out their disadvantages and advantages. The manuscript can support the searching interpretation of the obtained results which will be a good tool for the development of a number of fields, especially medicine what can help in the future detection and treatment of many serious diseases.

Graphic abstract

Strawberry agro-industrial by-products as a source of bioactive compounds: effect of cultivar on the phenolic profile and the antioxidant capacity

The post-harvest processing of strawberries generates considerable amounts of by-products that consist of the inedible parts of the fruit (sepal, calyx, stem, and non-marketable portion of the fruit), which is an environmental problem for local producers and industries. This study aimed to revalue these kinds of tissues through identifying and quantifying the genotype influence on the total phenolic content, phenolic profile, and the antioxidant activity of the by-products from three strawberry cultivars: 'Festival' (FE), 'San Andreas ' (SA), and 'Camino Real' (CR). The total phenolic content was determined by the Folin-Ciocalteu method, in-vitro antioxidant activity by the DPPH* radical scavenging method and the phenolic profile by PAD-HPLC. The different genotypes showed significant differences (p < 0.05) in total phenolic content (TPC), FE being the one with the highest TPC (14.97 g of gallic acid equivalents < GAE > /Kg of by-product < R >), followed by SA and CR cultivars. The antioxidant capacity of the SA and FE tissues were similar (p > 0.05) and higher (15.1-16.3 mmol Trolox equivalents < TE > /Kg R) than CR. Eight main phenolic compounds were identified and quantified on the three cultivars. Agrimoniin was the principal polyphenol (0.38-1.56 g/Kg R), and the cultivar FE had the highest concentration. This compound showed the highest correlation coefficient with the antioxidant capacity (R2 0.87; p < 0.001). This study highlighted the impact of the multi-cultivar systems in strawberry production on the bioactive potential and the diversity of secondary metabolites obtained from strawberry agro-industrial by-products at a low cost.

Effect of Chitosan–Pullulan Composite Edible Coating Functionalized with Pomegranate Peel Extract on the Shelf Life of Mango (Mangifera indica)

The polysaccharide based composite biomaterial (coating) used in preserving fruits and vegetables during storage is attracting increased attention as it is biodegradable material that prolongs shelf life. In the present investigation, chitosan–pullulan (50:50) composite edible coating was prepared with pomegranate peel extract (0.02 g/mL) as an active antioxidant agent. The effect of treatment with pomegranate peel extract enriched chitosan–pullulan composite edible coating on the shelf life of mango fruits during 18 days of storage period at room (23 °C) and cold (4 °C) temperature was evaluated. Results of the present study demonstrated that the application of chitosan–pullulan composite edible coating significantly (p ≤  0.05) influences the storage life of mango fruits at both storage temperatures. The chitosan–pullulan composite edible coating reduced the physiological loss in weight (PLW), and maintained total soluble solids (TSS), acidity and pH of coated mango fruits as compared to the control. In addition, fruit sensory quality such as freshness, color, taste and texture were also retained by the treatment. Furthermore, sustained firmness, phenolic content and antioxidant activity confirmed the effectiveness of the pomegranate peel extract enriched chitosan–pullulan composite edible coating on mango fruits. The phenolic, flavonoid and antioxidant activity of coated fruits were retained by pomegranate peel rich edible coating. Therefore, the chitosan–pullulan (50:50) combination with pomegranate peel extract can be used as an alternative preservation method to prolong the shelf life of mango fruits at room and cold storage conditions. However, more in-depth studies are required at farm and transit level without affecting the postharvest quality of mango fruits, providing more revenue for farmers and minimizing postharvest losses.

Root extracts of Anacardium occidentale reduce hyperglycemia and oxidative stress in vitro

Background

Hyperglycemia is the hallmark of diabetes, and the associated oxidative stress is a major concern that invites an array of diabetic complications. The traditional practices of medicare are of great, current interest due to the high cost and side effects of conventional diabetic medications. The present in vitro study focuses on evaluating the potential of various A. occidentale root extracts for their antihyperglycemic and antioxidant potentials.

Materials and methods

The four different solvent extracts petroleum ether (PEAO), chloroform (CHAO), ethyl acetate (EAAO), and 80 % methanol (80 % MAO) of A. occidentale roots were evaluated for their total phenolic, flavonoid, and antioxidant capacity. Using MIN6 pancreatic β-cells, the cytotoxicity of the extracts was evaluated by MTT assay and the antidiabetic potential by quantifying the insulin levels by ELISA at a higher concentration of glucose. The effect of 80 % MAO on INS gene expression was determined by qRT PCR analysis.

Results

Among the four different solvent extracts of A. occidentale roots, 80 % MAO showed the highest concentration of phenolics (437.33 ± 0.03 µg GAE/mg), CHAO to be a rich source of flavonoids (46.04 ± 0.1 µg QE/mg) and with the highest total antioxidant capacity (1865.33 ± 0.09 µg AAE/ mg). Evaluation of the free radical scavenging and reducing properties of the extracts indicated 80 % MAO to exhibit the highest activity. The MTT assay revealed the least cytotoxicity of all four extracts. 80 % MAO enhanced INS up-regulation as well as insulin secretion even under high glucose concentration (27mM).

Conclusions

The present study demonstrated that the A. occidentale root extracts have effective antihyperglycemic and antioxidative properties, together with the potential of normalizing the insulin secretory system of β-cells. Above mentioned properties have to be studied further by identifying the active principles of A. occidentale root extracts and in vivo effects. The prospect of the present study is identifying drug leads for better management of diabetes from the A. occidentale root extracts.

Graphical abstract

Phytochemical and antioxidant activity of Cadaba farinosa Forssk stem bark extracts

Cadaba farinosa is used in traditional medicine for treatment of cancer, diabetes, and rheumatism. The research was aimed at evaluating the phytochemical and antioxidant activity of the extracts. The powdered stem bark was extracted successively with the aid of Soxhlet extractor using n-hexane, ethyl acetate, and methanol. The resulting extracts were concentrated on rotary evaporator and the percentage yields were calculated. The phytochemical and TLC profiles of the extracts were studied. The antioxidant activity of the extracts and ascorbic acid (standard) were determined using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. The total phenolic content of the extracts and tannic acid (standard) were evaluated using Folin–Ciocalteu reagent. The percentage yields of n-hexane, ethyl acetate, and methanol extracts were found to be 1.19, 1.37, and 13.93%, respectively. The phytochemical screening revealed the presence of tannins, flavonoids, saponins, cardiac glycosides, alkaloids, and triterpenoids. The TLC profiles of the extracts revealed the presence of compounds as evidenced from their R f values. The total phenolic content of ethyl acetate and methanol extracts were found to be 135 and 112 mg, respectively. The free radical scavenging activity demonstrated by the extracts was comparable to ascorbic acid. The ethyl acetate extract had higher phenolic content and demonstrated the highest free radical scavenging with IC50 31.07 mg/mL. The results of research have provided strong preliminary evidence of antioxidant activity which may be because of phenolic compounds in the extracts.

In-vitro antioxidant and antimicrobial studies of ethanolic plant extracts of P. granatum, O. stamineus, A. bilimbi, M. nigra, and E. longifolia

BACKGROUND

Acne is a serious skin problem that affects mostly adolescents. The topical and systematic therapies are effective but could lead to several side effects and the emergence of antibacterial resistance of the acne-causing bacteria. Plant resources have been used as traditional medicine for centuries and can be the alternative therapies for acne treatment. Antioxidants are compounds that can prevent or delay the oxidation of substrates when present in low concentrations. Antioxidants are usually involved in several mechanisms of action, including the inhibition of free radical generation, enhancement of the scavenging capacity against free radicals, and reducing power.

METHODS

In this study, three antioxidant assays, DPPH, ABTS, and FRAP were used to evaluate the antioxidant properties of the ethanolic extracts of five plant extracts (A. bilimbi, M. nigra, O. stamineus, P. granatum, and E. longifolia). Furthermore, the study aimed to identify the most potent plant extracts and their combination which could provide better antibacterial activities against acne-causing bacteria. Ethanolic extracts of A. bilimbi, O. stamineus, M. nigra, P. granatum, and E. longifolia were prepared by the Ultrasound-Assisted Extraction (UAE) technique. Their phytochemical contents were screened using several biochemical tests and GC-MS analysis.

RESULTS

The study found that only the extracts of P. granatum and O. stamineus exhibited good antioxidant activity using DPPH assay (82.37% and 81.72% μg/mL respectively) and in ABTS assay (87.25% and 88.85% μg/mL respectively); their observed FRAP values were 115.1667 ± 5.6182 and 41.3860 ± 2.4583 μg/mL, respectively. The preliminary antibacterial screening using the disc diffusion method showed that P. granatum and O. stamineus were the most potent extracts; hence, both extracts were combined at the ratios of 1:1, 1:2, and 2:1 to a total concentration of 400 mg/mL.

DISCUSSION

The antibacterial efficacy of the mixture was studied using the disc diffusion method and the MIC value was determined. Both S. aureus and S. epidermidis were sensitive to all the individual and combined extracts but C. acnes was resistant to all of them.

CONCLUSION

The antibacterial activity of the combined extracts against S. aureus showed a synergistic effect at the ratio of 2:1 with the inhibitory zone diameter of 18.00 ± 1.00 mm and MIC value of 12.5 mg/mL; however, antagonistic effects were observed against S. epidermidis while no effect was noted against C. acnes. Therefore, all the selected plant extracts exhibited antibacterial activities against certain bacteria and their effects may be enhanced by combining the plant extracts.

Zinc biosorption by Dunaliella sp. AL-1: Mechanism and effects on cell metabolism

Phycoremediation is being considered as an eco-friendly and safe technology for toxics eradication from contaminated aquatic systems. The zinc biosorption capacity of Dunaliella sp. AL-1 was demonstrated. Zinc impacted cell growth and photosynthetic pigments accumulation showing exposure time and concentration-dependent effects. The investigation of the antioxidant protective response to zinc exposition proved a stimulation of guaiacol peroxidase (GPX) activity and an increased rate of total phenolics, flavonoids, condensed tannins and glutathione (GSH). The Box-Behnken design was used to optimize zinc removal conditions by Dunaliella sp. AL-1 strain. The maximum experimental zinc uptake was obtained when zinc concentration, algae dose, initial pH, and contact time were set at 25 mg/L, 0.5 g/L, 7.59 and 13 h 43 min, respectively. Under completely optimized conditions, the fraction of zinc removed intracellularly was much lower than the adsorbed on the cell surface. FTIR analysis Dunaliella sp. AL-1 biomass demonstrated that several functional groups as OH, CH₂, CO, PO, COO and CO may participate in the biosorption process. A comparative proteomic analysis through nano-HPLC coupled to LC-MS/MS, was performed from pre- and post-zinc treatments cells. Among 199 identified proteins, 60 were differentially expressed of which 41 proteins were down-regulated against 19 up-regulated ones. Target proteins have been demonstrated to be implicated in different metabolic processes mainly photosynthesis and antioxidant defenses.

Influence of Cooking Methods on Antioxidant Activities of Selected Leafy Vegetables Gymnema lactiferum, Wattakaka volubilis, and Argyreia populifolia in Sri Lanka

Green leafy vegetables (GLVs) are abundant in bioactive compounds and constitute a crucial part of a balanced diet. Sri Lankan green leafy vegetables which are edible and available for consumption have not been thoroughly investigated, whilst their consumption can deflate the risk of arising several degenerative diseases, such as cancer and cardiovascular diseases. The present study was aimed at evaluating the antioxidant capacities of the leafy vegetables, Gymnema lactiferum (Kurignan), Wattakaka volubilis (Aguna), and Argyreia populifolia (Girithilla), with different thermal treatments (70°C, 120°C, and 170°C) which are used in domestic cooking processes. Heat treatments significantly affect the antioxidant capacity and polyphenolic content of most vegetables analyzed, either increasing or decreasing the concentration of these compounds. In the presence of thermal treatments, Gymnema lactiferum (14.52-20.28 mg GAE/g DW) and Wattakaka volubilis (19.75-27.13 mg GAE/g DW) showed a significantly higher (p < 0.05) total phenolic content. The temperature treatment did not alter the ABTS radical scavenging activity in Gymnema lactiferum. In contrast, an increment of ferric reducing antioxidant power (41.26-54.85 mg TE/g DW) and DPPH radical scavenging activity (0.11-0.26 mg TE/g DW) was observed. Wattakaka volubilis treated at 170°C appeared to have a significantly higher amount (104.93 ± 1.41 mg TE/g DW) of ferric reducing antioxidant power compared to its raw form. All cooking processes with their corresponding thermal treatments caused a significantly lower (p < 0) amount of antioxidant capacity in Argyreia populifolia.

Biological activities of two polypore macrofungi (Basidiomycota) and characterization of their compounds using HPLC-DAD and LC-ESI-MS/MS

Members of Hymenochaetaceae fungi are among well-known macromycetes with various medicinal properties. The aim of this study was to investigate the biological activities of Phellinus tuberculosus and Fuscoporia ferruginosa collected in Iran. The antimicrobial, antioxidant, and cytotoxic activities of the two species were examined, and their phenolic and polysaccharide contents were quantified. Compounds were characterized by HPLC-DAD chromatography and LC-ESI-MS/MS spectroscopy. According to our results, the antibacterial and antioxidant effects of P. tuberculosus extracts were stronger than F. ferruginosa. Also, the effect of hydroalcoholic extracts was higher than the aqueous extract. Gram-positive bacteria were more sensitive to all extracts, especially Streptococcus mutans with a MIC of 0.7 mg/mL and MBC of 6.25 mg/mL. HPLC-DAD analyses detected gallic acid, caffeic acid, and syringic acid in both fungi. The LC-ESI-MS/MS confirmed the detected compounds in HPLC-DAD and showed the presence of several phenolic compounds such as phellifuropyranone, phelligridin, and hispidin, besides others. This study showed that F. ferruginosa and P. tuberculosus are potent medicinal fungi with antibacterial and antioxidant properties, with no toxic effect on normal HDF cells, and possess various bioactive compounds including styrylpyrone-type phenols with well-known bioactivities.

The Influence of Ripeness on the Phenolic Content, Antioxidant and Antimicrobial Activities of Pumpkins (Cucurbita moschata Duchesne)

Cucurbita moschata Duchesne (Cucurbitaceae) is a plant food highly appreciated for the content of nutrients and bioactive compounds, including polyphenols and carotenoids, which contribute to its antioxidant and antimicrobial capacities. The purpose of this study was to identify phenolic acids and flavonoids of Cucurbita moschata Duchesne using high-performance liquid chromatography–diode array detection–electrospray ionization tandem mass spectrometry (HPLC–DAD–ESI-MS) at different ripening stages (young, mature, ripened) and determine its antioxidant and antimicrobial activities. According to the results, phenolic acids and flavonoids were dependent on the maturity stage. The mature fruits contain the highest total phenolic and flavonoids contents (97.4 mg GAE. 100 g⁻¹ and 28.6 mg QE. 100 g⁻¹).A total of 33 compounds were identified. Syringic acid was the most abundant compound (37%), followed by cinnamic acid (12%) and protocatechuic acid (11%). Polyphenol extract of the mature fruits showed the highest antioxidant activity when measured by DPPH (0.065 μmol TE/g) and ABTS (0.074 μmol TE/g) assays. In the antimicrobial assay, the second stage of ripening had the highest antibacterial activity. Staphylococcus aureus was the most sensitive strain with an inhibition zone of 12 mm and a MIC of 0.75 mg L⁻¹. The lowest inhibition zone was obtained with Salmonella typhimurium (5 mm), and the MIC value was 10 mg L⁻¹.

Antioxidative and Anti-Inflammatory Phytochemicals and Related Stable Paramagnetic Species in Different Parts of Dragon Fruit

In this study, we investigated the antioxidant and anti-inflammatory phytochemicals and paramagnetic species in dragon fruit using high-performance liquid chromatography (HPLC) and electron paramagnetic resonance (EPR). HPLC analysis demonstrated that dragon fruit is enriched with bioactive phytochemicals, with significant variations between each part of the fruit. Anthocyanins namely, cyanidin 3-glucoside, delphinidin 3-glucoside, and pelargonidin 3-glucoside were detected in the dragon fruit peel and fresh red pulp. Epicatechin gallate, epigallocatechin, caffeine, and gallic acid were found in the dragon fruit seed. Additionally, 25–100 mg × L⁻¹ of dragon fruit pulp and peel extracts containing enrichment of cyanidin 3-glucoside were found to inhibit the production of reactive oxygen species (ROS), reactive nitrogen species (RNS), inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) in cell-based studies without exerted cytotoxicity. EPR primarily detected two paramagnetic species in the red samples. These two different radical species were assigned as stable radicals and Mn²⁺ (paramagnetic species) based on the g-values and hyperfine components. In addition, the broad EPR line width of the white peel can be correlated to a unique moiety in dragon fruit. Our EPR and HPLC results provide new insight regarding the phytochemicals and related stable intermediates found in various parts of dragon fruit. Thus, we suggest here that there is the potential to use dragon fruit peel, which contains anthocyanins, as a natural active pharmaceutical ingredient.

Changes in antinutrients, phenolics, antioxidant activities and in vitro α-glucosidase inhibitory activity in pumpkin leaves (Cucurbita moschata) during different domestic cooking methods

Pumpkin leaves (Cucurbita moschata) were subjected to different household cooking methods (boiling, microwaving, steaming, and stir-frying) to evaluate their effect on antinutrients, phenolic compounds, antioxidant properties (ABTS, and DPPH) and in vitro α-glucosidase activity. All cooking methods studied significantly reduced the antinutrients and antioxidant activities, whilst phenolic compounds p-coumaric and ferulic acids significantly increased. The cooking methods reduced the oxalates by more than 50%, tannins by 47% and phytates by 79.22%. Steaming and boiling resulted in highest concentrations of p-coumaric (195.40 mg kg^-1) and ferulic acids (103.90 mg kg^-1) compared to other methods. Overall, boiled leaves retained the highest total phenolic compounds, whilst steamed leaves retained the highest antioxidant capacity. Raw pumpkin leaf extracts showed higher in vitro α-glucosidase inhibitory effects than the cooked leaves. Thus, cooking affected the inhibitory effect of in vitro α-glucosidase activity.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-021-00916-w.

Untargeted Phytochemical Profile, Antioxidant Capacity and Enzyme Inhibitory Activity of Cultivated and Wild Lupin Seeds from Tunisia

Lupin seeds can represent a valuable source of phenolics and other antioxidant compounds. In this work, a comprehensive analysis of the phytochemical profile was performed on seeds from three Lupinus species, including one cultivar (Lupinus albus) and two wild accessions (Lupinus cossentinii and Lupinus luteus), collected from the northern region of Tunisia. Untargeted metabolomic profiling allowed to identify 249 compounds, with a great abundance of phenolics and alkaloids. In this regard, the species L. cossentinii showed the highest phenolic content, being 6.54 mg/g DW, followed by L. luteus (1.60 mg/g DW) and L. albus (1.14 mg/g DW). The in vitro antioxidant capacity measured by the ABTS assay on seed extracts ranged from 4.67 to 17.58 mg trolox equivalents (TE)/g, recording the highest values for L. albus and the lowest for L. luteus. The DPPH radical scavenging activity ranged from 0.39 to 3.50 mg TE/g. FRAP values varied between 4.11 and 5.75 mg TE/g. CUPRAC values for lupin seeds ranged from 7.20 to 8.95 mg TE/g, recording the highest for L. cossentinii. The results of phosphomolybdenum assay and metal chelation showed similarity between the three species of Lupinus. The acetylcholinesterase (AChE) inhibition activity was detected in each methanolic extract analyzed with similar results. Regarding the butyrylcholinesterase (BChE) enzyme, it was weakly inhibited by the Lupinus extracts; in particular, the highest activity values were recorded for L. albus (1.74 mg GALAE/g). Overall, our results showed that L. cossentinii was the most abundant source of polyphenols, consisting mainly in tyrosol equivalents (5.82 mg/g DW). Finally, significant correlations were outlined between the phenolic compounds and the in vitro biological activity measured, particularly when considering flavones, phenolic acids and lower-molecular-weight phenolics.

Assessing the ethnobotanical potential of Carissa opaca berries by merging outcomes from metabolomics profiling, enzyme assays, and in silico docking studies

The phytochemical profile of Carissa opaca fruit extract and fractions was established through dereplication strategies employing LC-MS/MS and global natural product social molecular networking (GNPS). Crude extract and fractions were evaluated for their potential to inhibit α-glucosidase and urease in vitro. Flavonoid-O-glycosides, flavonoid-C-glycosides, flavonoids, proanthocyanidin B2, phenolics, and triterpenoids were annotated as the major classes of secondary metabolites present in the extract and fractions. α-Glucosidase inhibition was associated with n-butanol and ethyl acetate fractions comparable to acarbose (IC₅₀ = 120.43 µg/mL) with IC₅₀ values of 123.67 and 131.72 µg/mL, respectively. The ethyl acetate fraction showed good urease inhibition comparable with thiourea (IC₅₀ = 103.71 µg/mL) with an IC₅₀ value of 109.14 µg/mL. Molecular docking studies of compounds observed in the crude extract and bioactive fractions had significant binding scores, which supported results for enzyme inhibition in vitro. This study provided a detailed phytochemical profile of C. opaca fruit and its enzyme inhibition potential.

Elevated CO2 modulates the effect of heat stress responses in Triticum aestivum by differential expression of isoflavone reductase-like (IRL) gene

Two wheat genotypes forming high and low biomass (HB and LB), exhibiting differential expression of an isoflavone reductase-like (IRL) gene, and resulting in contrasting grain yield under heat stress field conditions, were analyzed in detail for their responses under controlled heat and elevated CO2 conditions. Significant differences in IRL expression between the two lines were hypothesized to be the basis of their differential performance under the tested conditions and their stress tolerance potential. By a holistic approach integrating advanced cell physiological phenotyping of the antioxidative and phytohormone system in spikes and leaves with measurements of ecophysiological and agronomic traits, the genetic differences of the genotypes in IRL expression were assessed. In response to heat and elevated CO2, the two genotypes showed opposite regulation of IRL expression, which was associated with cytokinin concentration, total flavonoid contents, activity of superoxide dismutase, antioxidant capacity and photosynthetic rate in leaves and cytokinin concentration and ascorbate peroxidase activity in spikes. Our study showed that IRL expression is associated with wheat yield performance under heat stress at anthesis, mediated by diverse physiological mechanisms. Hence, based on our results, the IRL gene is a promising candidate for developing genetic markers for breeding heat-tolerant wheat.

Determination of Mineral Composition and Phenolic Content and Investigation of Antioxidant, Antidiabetic, and Antibacterial Activities of Crocus sativus L. Aqueous Stigmas Extracts

The aim of this study is to investigate the in vitro antioxidant, antidiabetic, and antibacterial activities of Moroccan and Italian Crocus sativus (L.) stigmas extracts. The antioxidant activity was evaluated by DPPH radical scavenging assay, and the results showed that the Moroccan extract has a powerful antioxidant activity with an IC₅₀ of 0.32 ± 0.059 μg/mL compared to the Italian extract (IC₅₀ of 3.14 ± 0.021 μg/mL). Additionally, the antidiabetic activity was evaluated by using alpha-amylase and alpha-glucosidase inhibition assay, and both extracts showed significant antidiabetic activity. However, the antibacterial activity was evaluated by the disc diffusion method to determine the inhibitory diameters and microplate dilutions method to determine the minimum inhibitory concentration. Our findings revealed that both Moroccan and Italian extracts were more effective against Gram-positive than Gram-negative bacteria. From this study, we can conclude that the studied extracts of C. sativus are rich in natural compounds and could have a broad application in the pharmaceutical, food, and medical fields.

Phytochemical Profile, Antioxidant Capacity, α-Amylase and α-Glucosidase Inhibitory Potential of Wild Moroccan Inula viscosa (L.) Aiton Leaves

Medicinal plants offer imperative sources of innovative chemical substances with important potential therapeutic effects. Among them, the members of the genus Inula have been widely used in traditional medicine for the treatment of several diseases. The present study investigated the antioxidant (DPPH, ABTS and FRAP assays) and the in vitro anti-hyperglycemic potential of aerial parts of Inula viscosa (L.) Aiton (I. viscosa) extracts through the inhibition of digestive enzymes (α-amylase and α-glucosidase), responsible of the digestion of poly and oligosaccharides. The polyphenolic profile of the Inula viscosa (L.) Aiton EtOAc extract was also investigated using HPLC-DAD/ESI-MS analysis, whereas the volatile composition was elucidated by GC-MS. The chemical analysis resulted in the detection of twenty-one polyphenolic compounds, whereas the volatile profile highlighted the occurrence of forty-eight different compounds. Inula viscosa (L.) Aiton presented values as high as 87.2 ± 0.50 mg GAE/g and 78.6 ± 0.55mg CE/g, for gallic acid and catechin, respectively. The EtOAc extract exhibited the higher antioxidant activity compared to methanol and chloroform extracts in different tests with (IC50 = 0.6 ± 0.03 µg/mL; IC50 = 8.6 ± 0.08 µg/mL; 634.8 mg ± 1.45 AAE/g extract) in DPPH, ABTS and FRAP tests. Moreover, Inula viscosa (L.) Aiton leaves did show an important inhibitory effect against α-amylase and α-glucosidase. On the basis of the results achieved, such a species represents a promising traditional medicine, thanks to its remarkable content of functional bioactive compounds, thus opening new prospects for research and innovative phytopharmaceuticals developments.

In vitroanti-oxidant and cytotoxic activities of gold nanoparticles synthesized from an aqueous extract of theXylopia aethiopicafruit

The development of gold nanoparticles (AuNPs) using a green approach has drawn considerable interest in the field of nanomedicine. Its wide application in clinical diagnosis, imaging and therapeutics portrays its importance for human existence. In this study, we reported on the biogenic synthesis of AuNPs using the aqueous extract of theXylopia aethiopicafruit (AEXAf), which acts as both a reducing and stabilizing agent. The characterization of AEXAf-AuNPs was performed using ultraviolet-visible spectroscopy, dynamic light scattering and zeta potential measurements, high-resolution transmission electron microscopy and Fourier transform-infrared spectroscopy. Thein vitroanti-oxidant activities of the AEXAf-AuNPs and AEXAf were evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing anti-oxidant power. Thein vitrocytotoxic activities of the AEXAf-AuNPs and AEXAf against breast and colorectal cancer cells were evaluated using 3,-(4,5 dimethylthiazol)-2,5 diphenyl tetrazolium bromide (MTT) viability and annexin V/PI assays. The AEXAf-AuNPs exhibited surface plasmon absorption maximum at 522 nm and were stable for 4 weeks. The average size of the AEXAf-AuNPs was 10.61 ± 3.33 nm on the high-resolution transmission electron microscopy images. Thein vitroanti-oxidant activities of the AEXAf-AuNPs and AEXAf were concentration dependent. The AEXAf-AuNPs were cytotoxic to the cancer cells and non-toxic to the non-cancerous human fibroblast cells (KMST-6) (up to 200μg ml^-1). From these results, the AEXAf-AuNPs showed good anti-oxidant and anti-cancer activities, and can be suggested as a possible therapeutic agent for breast and colorectal cancer.

Antidiabetic, Antimicrobial, and Molecular Profiling of Selected Medicinal Plants

Natural products have been the center of attraction ever since they were discovered. Among them, plant-based natural products were popular as analgesics, anti-inflammatory, antidiabetic, and cosmetics and possess widespread biotechnological applications. The use of plant products as cosmetics and therapeutics is deep-rooted in Nepalese society. Although there are few ethnobotanical studies conducted, extensive research of these valuable medicinal plants has not been a priority due to the limitation of technology and infrastructure. Here, we selected 4 traditionally used medicinal plants to examine their bioactive properties and their enzyme inhibition potential. α-Glucosidase and α-amylase inhibitory activities were investigated using an in vitro model followed up by antioxidant and antimicrobial activities. The present study shows that ethyl acetate fraction of Melastoma melabathrium (IC₅₀ 9.1 ± 0.3 µg/mL) and water fraction Acacia catechu (IC₅₀ 9.0 ± 0.6 µg/mL) exhibit strong α-glucosidase inhibition. Likewise, the highest α-amylase inhibition was shown by crude extracts of Ficus religiosa (IC₅₀ 29.2 ± 1.2 µg/mL) and ethyl acetate fractions of Shorea robusta (IC₅₀ 69.3 ± 1.1 µg/mL), and the highest radical scavenging activity was shown by F. religiosa with an IC₅₀ 67.4 ± 0.6 µg/mL. Furthermore, to identify the metabolites within the fractions, we employed high-resolution mass spectrometry (LC-HRMS) and annotated 17 known metabolites which justify our assumption on activity. Of 4 medicinal plants examined, ethyl acetate fraction of S. robusta, ethyl acetate fraction of M. melabathrium, and water or ethyl acetate fraction of A. catechu extracts illustrated the best activities. With our study, we set up a foundation that provides authentic evidence to the community for use of these traditional plants. The annotated metabolites in this study support earlier experimental evidence towards the inhibition of enzymes. Further study is necessary to explore the clinical efficacy of these secondary molecules, which might be alternatives for the treatment of diabetes and pathogens.

Antioxidant and Anticancer Efficacies of Anethum graveolens against Human Breast Carcinoma Cells through Oxidative Stress and Caspase Dependency

Anethum graveolens, belonging to the family Apiaceae, has been extensively used for medicinal and therapeutic purposes since long. Plants encompass rich number of effective constituents with less toxicity. Thus, nowadays, the attempts are being made to search plant constituents that can prevent and reverse the chronic diseases, such as cancer. In this study, an in vitro antioxidant and anticancer efficacies of Anethum graveolens (AG-ME) were studied on human breast (MCF-7), lung (A-549), and cervical (HeLa) carcinoma cell lines. The antioxidant efficacies of AG-ME were evaluated by total antioxidant, DPPH radical scavenging, H2O2 scavenging, and ferrous reducing antioxidant assays. Further, the anticancer potential of AG-ME was also determined against different cancer cell lines. The AG-ME exhibited strong antioxidant activities as observed by antioxidant assays. AG-ME also showed a dose-dependent anticancer/cytotoxic potential against MCF-7, A-549, and HeLa cell lines. The AG-ME-induced reduction in GSH and increase in SOD activities indicates the role of oxidative stress in AG-ME-induced MCF-7 cell death. The results also exhibited that AG-ME triggered ROS production and significantly reduced MMP level. Moreover, a dose-dependent increase in caspase-3 and caspase-9 activities suggests that the AG-ME-induced MCF-7 cell death is caspase-dependent. Together, the present study provides reasoning and reassurance for the uses of A. graveleons for medical purposes as an antioxidant and anticancer agent. Additional investigations are required to examine biological and anticancer activities under an in vivo system to discover a possible beneficial use of AG-ME against diseases.

New phenolic glycosides from Anemone chinensis Bunge and their antioxidant activity

ABATRACTNine compounds, five phenolic glycosides (1, 2, 4-6), three phenylpropanoids (7-9), and a furanone glycoside (3), were isolated from aqueous soluble extract of the dried roots of Anemone chinensis Bunge. The structures of new compounds (1-4) were elucidated by comprehensive spectroscopic data analysis as well as chemical evidence. Pulsatillanin A (1) demonstrated significant antioxidant effects through scavenging free radical in DPPH assay, and relieved the oxidative stress in LPS-induced RAW 264.7 cells by reducing ROS production, enhancing antioxidant enzyme SOD activity, replenishing depleted GSH in a dose-dependent manner. Western blot analysis revealed that 1 showed antioxidant activity via activating Nrf2 signaling pathway.

Inhibition of biofilm and quorum sensing-regulated virulence factors in Pseudomonas aeruginosa by Cuphea carthagenensis (Jacq.) J. F. Macbr. Leaf extract: An in vitro study

ETHNOPHARMCOLOGICAL RELEVANCE

Microbial biofilm formation, a quorum sensing (QS) regulated process, is one of the major causes of nosocomial and chronic infections, foodborne diseases, and associated deaths. Various approaches have been used to eradicate the menace of biofilm. Ethnomedicinal plants as potent antibiofilm agents are gaining a lot of interest in an era where the drug resistance is increasing and the availability of potent antibiotics is no longer promised. In this context, the methanol extract of Cuphea carthagenensis (CCMD), an ethno-medicinal and culinary herb, was evaluated as an antibiofilm and anti-QS agent against Pseudomonas aeruginosa.

AIM OF THE STUDY

The aim of the study is to evaluate the antibiofilm and anti-QS activity of an ethnomedicinal plant against a strong biofilm forming microorganism, P. aeruginosa.

METHODS

Antibiofilm activity of CCMD was demonstrated at different concentrations by Tissue Culture Plate, Test Tube method and other microscopic techniques. The effect of CCMD on QS and QS-related virulence factors viz. Pyocyanin, exopolymeric substance matrix (EPS), total protease, elastase, pyoverdin and swimming motility in P. aeruginosa were also evaluated. Antioxidant activity (DPPH & FRAP), total phenolic and flavonoid content were also checked. In order to determine the composition of the extract HPLC analysis was also performed.

RESULTS

In vitro study demonstrated a significant inhibition of biofilm formation (81.88 ± 2.57%) as well as production of QS-dependent virulence factors in P. aeruginosa. The extract also inhibited violacein production (83.31 ± 2.77%) in Chromobacterium violaceum which correlates with the reduction in QS-mediated virulence factors. The extract showed 64.79% ± 0.83% DPPH scavenging activity and reduction of ferricyanide complex (Fe³⁺) to the ferrous form (Fe²⁺) in DPPH and FRAP assay, respectively. Furthermore, the extract showed thermal stability and does not have any growth inhibitory effect on P. aeruginosa. The HPLC analysis demonstrated the presence of ellagic acid, ascorbic acid and hippuric acid in the extract.

CONCLUSION

This work is the first to demonstrate that C. carthagenensis can attenuate biofilm formation and QS-mediated virulence factors of P. aeruginosa. Further investigation is required to use this ethnomedicinal plant (CCMD) as an important source of antibiofilm agents.

Silicon Application Modulates Growth, Physio-Chemicals, and Antioxidants in Wheat (Triticum aestivum L.) Exposed to Different Cadmium Regimes

Silicon (Si) application enhanced the tolerance of plants against different environmental stresses. Therefore, objective of the study revealed that foliar applied Si alleviates the adverse effect of Cd by enhancing the growth, metabolite accumulation, strengthening the antioxidant defense system, reducing oxidative injury, improving plant nutrient status, and decreasing the Cd uptake in wheat. The surface sterilized seeds of Sahar-2006 (tolerant) and Inqalab-91 (sensitive) having the differential metal tolerance capacity were sown in plastic pots containing normal and Cd spiked sandy loamy soil. The design of experiments was completely randomized with 3 replicates per treatment. Two weeks after germination, plants were sprayed with different concentrations of Si (1.5 and 3 mM) with 0.1% surfactant in the form of Tween-20. The plants were harvested after 2 weeks of Si application to determine various attributes. High concentration of Cd (25 mg kg-1) decreased growth-related-attributes, essential nutrient uptake and increase the levels of oxidative stress indicators. The application of Si increased the growth-related attributes, photosynthetic pigments, essential nutrient uptake and also enhanced the activities of various antioxidant compounds (superoxide dismutase (SOD), peroxidase (POD, ascorbate peroxidase (APX) and catalase (CAT) by decreasing the contents of oxidative stress indicators and Cd uptake in root and shoot of both wheat cultivars. Sahar-2006 cultivar showed more tolerance to Cd regimes than that of Inqalab-91 as clear from greater plant dry masses. Thus, our results showed that the applied Si level (3 mM) is an efficient strategy for field use in the areas, where slightly Cd polluted soils limit the agriculture production.

DETERMINATION OF TOTAL PHENOLIC CONTENT FROM PLANT EXTRACTS USED IN COSMETIC PURPOSE

Spectrometric analysis belongs to a group of measurement methods used for their simplicity and large selectivity to solve various problems of analytes. The total phenolic content of different plant extracts used for cosmetic purpose was determined by a slightly modified version of traditionally Folin-Ciocalteau method. The objective of this work was the validation of UV-Vis spectrometric method, investigation of uncertainty sources when measuring gallic acid concentration and evaluation of the calibration equation effect on measurement uncertainty of UV– Vis spectrophotometer. Validation was performed by studying analytical curve linearity (R2=0.9995) and range (37.5 – 225 mg L-1), estimated limit of detection (LOD, 0.11mg L-1) and limit of quantification (LOQ, 0.37 mg L-1), precision (%RSD, 0.14 – 1.34), recoveries (83-110%) and stability (%RSD, 0.8 – 2.83). To obtain more representative values for precision, recoveries and stability simultaneous replicates at different times, on different matrices including plant (marigold, chamomile and lavender) were performed during the study period. The validated method was successfully applied to determine TPC in marigold extracts. For chamomile and lavender extracts, the spectrometric method presented only acceptable precision, among all the performance parameters studied. The sources of the gallic acid concentration measurement uncertainty include purity, volume of flasks, mass and the calibration equation. The results indicated that the uncertainty components from purity were the smallest. An important source of the uncertainty was the mass.The volumes of the volumetric flasks had only modest effect on the uncertainty. The contribution of calibration equation is the greatest from all sources.

Chemical Composition and Pharmacological Evaluation and of Toddalia asiatica (Rutaceae) Extracts and Essential Oil by in Vitro and in Silico Approaches

Toddalia asiatica (L.) Lam. is extensively used in traditional medicinal systems by various cultures. Despite its frequent use in traditional medicine, there is still a paucity of scientific information on T. asiatica growing on the tropical island of Mauritius. Therefore, the present study was designed to appraise the pharmacological and phytochemical profile of extracts (methanol, ethyl acetate and water) and essential oil obtained from aerial parts of T. asiatica. Biological investigation involved the evaluation of in vitro antioxidant and enzyme inhibitory potentials. The chemical profile of the EO was determined using gas chromatography coupled to mass spectrometry (GC/MS) analysis, while for the extracts, the total phenolic (TPC) and flavonoid content were quantified as well as their individual phenolic compounds by LC/MS/MS. Quinic acid, fumaric acid, chlorogenic acid, quercitrin and isoquercitrin were the main compounds in the extracts. Highest total phenolic (82.5±0.94 mg gallic acid equivalent (GAE/g)) and flavonoid (43.8±0.31 mg rutin equivalent (RE/g)) content were observed for the methanol extract. The GC/MS analysis has shown the presence of 26 compounds with linalool (30.9 %), linalyl acetate (20.9 %) and β-phellandrene (7.9 %) being most abundant components in the EO. The extracts and EO showed notable antioxidant properties, with the methanol extract proved to be superior source of antioxidant compounds. Noteworthy anti-acetylcholinesterase (AChE) and anti-butyrylcholinesterase (BChE) effects were recorded for the tested samples, while only the methanol and ethyl acetate extracts were active against tyrosinase. With respect to antidiabetic effects, the extracts and EO were potent inhibitors of α-glucosidase, while modest activity was recorded against α-amylase. Docking results showed that linalyl acetate has the highest affinity to interact with the active site of BChE with docking score of -6.25 kcal/mol. The findings amassed herein act as a stimulus for further investigations of this plant as a potential source of bioactive compounds which can be exploited as phyto-therapeutics.

Pharmacological Potential and Chemical Characterization of Bridelia ferruginea Benth.-A Native Tropical African Medicinal Plant

To avail the possible pharmacological actions of Brideliaferruginea Benth., the present investigation was designed to quantitatively analyze the total flavonoid and phenolic contents and assess the various antioxidant and enzyme inhibition properties of leaf and stem bark extracts (ethyl acetate, water and methanolic) of B. ferruginea. Anti-proliferative effect was also investigated against human colon cancer cells (HCT116) as well as the antimicrobial potential against multiple bacterial and fungal (yeasts and dermatophytes) strains. The methanolic and water extracts of the stem bark demonstrated the highest phenolic content (193.58 ± 0.98 and 187.84 ± 1.88 mg/g, respectively), while the leaf extracts showed comparatively higher flavonoid contents (24.37-42.31 mg/g). Overall, the methanolic extracts were found to possess the most significant antioxidant potency. Compared to the other extracts, methanolic extracts of the B. ferruginea were revealed to be most potent inhibitors of acetyl- and butyryl-cholinesterases, tyrosinase α-amylase, except α-glucosidase. Only the ethyl acetate extracts were found to inhibit glucosidase. Additionally, the stem bark methanolic extract also showed potent inhibitory activity against E. coli and gram-positive bacteria (MIC (minimum inhibitory concentration): 2.48-62.99 µg/mL), as well as all the tested fungi (MIC: 4.96-62.99 µg/mL). In conclusion, B. ferruginea can be regarded as a promising source of bioactive compounds displaying multifunctional pharmacological activities and thus is a potential candidate for further investigations in the endeavor to develop botanical formulations for pharmaceutical and cosmeceutical industries.

Deeper Insights on Alchornea cordifolia (Schumach. & Thonn.) Müll.Arg Extracts: Chemical Profiles, Biological Abilities, Network Analysis and Molecular Docking

Alchornea cordifolia (Schumach. & Thonn.) Müll. Arg. is a well-known African medicinal plant traditionally used for various healing purposes. In the present study, methanolic, ethyl acetate and infusion extracts of A. cordifolia leaves were studied for their total phenolic and flavonoid contents and screened for their chemical composition. Moreover, the enzyme (acetyl- and butyryl-cholinesterases, α-amylase, α-glucosidase, and tyrosinase) inhibitory and cytotoxicity activities on HepG2: human hepatocellular carcinoma cells, B16 4A5: murine melanoma cells, and S17: murine bone marrow (normal) cells of extracts were evaluated. Finally, components-targets and docking analyzes were conducted with the aim to unravel the putative mechanisms underlying the observed bio-pharmacological effects. Interestingly, the infusion and methanolic extracts showed significantly higher total phenolic and flavonoid contents compared with the ethyl acetate extract (TPC: 120.38–213.12 mg GAE/g and TFC: 9.66–57.18 mg RE/g). Besides, the methanolic extracts followed by the infusion extracts were revealed to contain a higher number of compounds (84 and 74 compounds, respectively), while only 64 compounds were observed for the ethyl acetate extract. Gallic acid, ellagic acid, shikimic acid, rutin, quercetin, myricetin, vitexin, quercitrin, kaempferol, and naringenin were among the compounds that were commonly identified in all the studied extracts. Additionally, the methanolic and infusion extracts displayed higher antioxidant capacity than ethyl acetate extract in all assays performed. In ABTS and DPPH radical scavenging assays, the methanol extract (500.38 mg TE/g for DPPH and 900.64 mg TE/g for ABTS) exhibited the best ability, followed by the water and ethyl acetate extracts. Furthermore, the extracts exhibited differential enzyme inhibitory profiles. In particular, the methanolic and infusion extracts showed better cytotoxic selectivity activity against human hepatocellular carcinoma cells. Overall, this study demonstrated A cordifolia to be a species worthy of further investigations, given its richness in bioactive phytochemicals and wide potentialities for antioxidants and pharmacological agents.

Antioxidant-Rich Woodfordia fruticosa Leaf Extract Alleviates Depressive-Like Behaviors and Impede Hyperglycemia

Dhaiphul (Woodfordia fruticosa) is a frequently demanded plant in South-East Asian regions for its diverse medicinal values. This study was proposed to examine antioxidant, antidiabetic, and antidepressant potentials of methanol extract of W. fruticosa leaves (MEWF) and its derived n-hexane (NHFMEWF) and ethyl acetate (EAFMEWF) fractions through in vitro, in vivo, and computational models. Among test samples, MEWF and EAFMEWF contained the highest phenolic content and showed maximal antioxidant activity in DPPH radical scavenging and ferric reducing power assays. In comparison, NHFMEWF possessed maximum flavonoid content and a significantly potent α-amylase inhibitory profile comparable with positive control acarbose. In animal models of depression (forced swimming and tail suspension test), EAFMEWF and NHFMEWF demonstrated a dose-dependent antidepressant-like effect; explicitly, the depressive-like behaviors significantly declined in EAFMEWF-treated dosing groups in contrast to the control group. In the computational analysis, previously isolated flavonoid compounds from Dhaiphul leaves manifested potent binding affinity against several key therapeutic target proteins of diabetes and depressive disorders including α-amylase, serotonin transporter, dopamine transporter, and neuronal nitric oxide synthase with varying pharmacokinetics and toxicity profiles. This research's outcomes may provide potential dietary supplements for mitigating hyperglycemia, cellular toxicity, and depressive disorder.

Polyphenolics and triterpenes presence in chloroform extract of Dicranopteris linearis leaves attenuated paracetamol-induced liver intoxication in rat

Introduction

Water-soluble, but not lipid-soluble, extract of Dicranopteris linearis leaves has been proven to possess hepatoprotective activity. The present study aimed to validate the hepatoprotective and antioxidant activities, and phytoconstituents of lipid-soluble (chloroform) extract of D. linearis leaves.

Methods

The extract of D. linearis leaves (CEDL; 50, 250 and 500 mg/kg) was orally administered to rats for 7 consecutive days followed by the oral administration of 3 g/kg PCM to induce liver injury. Blood was collected for liver function analysis while the liver was obtained for histopathological examination and endogenous antioxidant activity determination. The extract was also subjected to antioxidant evaluation and phytochemicals determination via phytochemical screening, HPLC and UPLC-HRMS analyses.

Results

CEDL exerted significant (p < 0.05) hepatoprotective activity at 250 and 500 mg/kg and significantly (p < 0.05) reversed the PCM-induced decrease in rat’s liver endogenous antioxidant (catalase and superoxide dismutase) level. CEDL possessed a high antioxidant capacity when measured using the ORAC assay, but a low total phenolic content value and radical scavenging activity as confirmed via several radical scavenging assays, which might be attributed particularly to the presence of triterpenes. Phytochemicals screening demonstrated the presence of triterpenes and flavonoids, while UPLC-HRMS analysis showed the presence of polyphenols belonging to the hydroxybenzoic acids, hydroxycinammates and flavonoid groups.

Discussion and conclusion

Lipid-soluble bioactive compounds of CEDL demonstrated hepatoprotective effect against PCM intoxication partly via the modulation of the endogenous antioxidant defense system, and exerted high antioxidant capacity. Further investigation is warranted to identify the potential hepatoprotective leads from CEDL for future drug development.

Antimicrobial activity of polyphenolic compounds from Spirulina against food-borne bacterial pathogens

Food-borne drug-resistant bacteria have adverse impacts on both food manufacturers and consumers. Disillusionment with the efficacy of current preservatives and antibiotics for controlling food-borne pathogens, especially drug-resistant bacteria, has led to a search for safer alternatives from natural sources. Spirulina have been recognized as a food supplement, natural colorant, and enriched source of bioactive secondary metabolites. The main objectives of this study were to isolate polyphenolic compounds from Spirulina and analyze their antibacterial potential against drug-resistant food-borne bacterial pathogens. We found that fraction B of methanol extract contained a high quantity of polyphenols exhibiting broad spectrum antimicrobial effects against drug-resistant food-borne bacterial pathogens. Potential secondary metabolites, such as benzophenone, dihydro-methyl-phenylacridine, carbanilic acid, dinitrobenzoate, propanediamine, isoquinoline, piperidin, oxazolidin, and pyrrolidine, were identified by gas chromatography and mass spectrophotometry (GCMS). These metabolites are active against both gram-positive and gram-negative pathogens. Our work suggests that phenolic compounds from Spirulina provide a natural and sustainable source of food preservatives for future use.

In vivo Antibacterial Activity of Star Anise (Illicium verum Hook.) Extract Using Murine MRSA Skin Infection Model in Relation to Its Metabolite Profile

Introduction

Star anise fruits (Illicium verum Hook.) have been used as an important treatment in traditional Chinese medicine. The previous studies reported the activity of the non-polar fractions as potential sources of antibacterial metabolites, and little was done concerning the polar fractions of star anise.

Methods

The antibacterial activity of the star anise aqueous methanolic (50%) extract against multidrug-resistant Acinetobacter baumannii AB5057 and methicillin-resistant Staphylococcus aureus (MRSA USA300) was investigated in vitro (disc diffusion assay, minimum bactericidal concentration determination, anti-biofilm activity and biofilm detachment activity). The antibacterial activity was further tested in vivo using a murine model of MRSA skin infection. Ultra-performance liquid chromatography coupled to high-resolution mass spectrometry (UPLC/HRMS) approach was applied for the identification of the metabolites responsible for the antibacterial activity. The antioxidant potential was evaluated using five in vitro assays: TAC (total antioxidant capacity), DPPH, ABTS, FRAP (ferric reducing antioxidant power) and iron-reducing power.

Results

In vitro, star anise aqueous methanolic extract showed significant inhibition and detachment activity against biofilm formation by the multidrug-resistant and highly virulent Acinetobacter baumannii AB5057 and MRSA USA300. The topical application of the extract in vivo significantly reduced the bacterial load in MRSA-infected skin lesions. The extract showed strong antioxidant activity using five different complementary methods. More than seventy metabolites from different classes were identified: phenolic acids, phenylpropanoids, sesquiterpenes, tannins, lignans and flavonoids.

Conclusion

This study proposes the potential use of star anise polar fraction in anti-virulence strategies against persistent infections and for the treatment of staphylococcal skin infections as a topical antimicrobial agent. To our knowledge, our research is the first to provide the complete polar metabolome list of star anise in an approach to understand the relationship between the chemistry of these metabolites and the proposed antibacterial activity.

Chemical Composition, Antioxidant and Anticancer Activities of Leptocarpha rivularis DC Flower Extracts

An evaluation of antioxidant and anticancer activity was screened in Leptocarpha rivularis DC flower extracts using four solvents (n-hexane (Hex), dichloromethane (DCM), ethyl acetate (AcOEt), and ethanol (EtOH)). Extracts were compared for total extract flavonoids and phenol contents, antioxidant activity (2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH), ferric reducing antioxidant potential (FRAP), total reactive antioxidant properties (TRAP) and oxygen radical absorbance capacity (ORAC)) across a determined value of reduced/oxidized glutathione (GSH/GSSG), and cell viability (the sulforhodamine B (SRB) assay). The most active extracts were analyzed by chromatographic analysis (GC/MS) and tested for apoptotic pathways. Extracts from Hex, DCM and AcOEt reduced cell viability, caused changes in cell morphology, affected mitochondrial membrane permeability, and induced caspase activation in tumor cell lines HT-29, PC-3, and MCF-7. These effects were generally less pronounced in the HEK-293 cell line (nontumor cells), indicating clear selectivity towards tumor cell lines. We attribute likely extract activity to the presence of sesquiterpene lactones, in combination with other components like steroids and flavonoids.

Collagen biosynthesis stimulation and anti-melanogenesis of bambara groundnut (Vigna subterranea) extracts

CONTEXT

Bambara groundnut (BG), originally from Africa, is widely distributed in Asian countries, especially in southern Thailand, and is used for food and functional foods. There is no report on the use of BG for ethnomedicine or cosmetics.

OBJECTIVE

To investigate collagen biosynthesis stimulation and anti-melanogenesis of the BG extracts.

MATERIALS AND METHODS

The hulls (H) and seeds (S) of BG were collected from Trang province, Thailand and extracted by Soxhlet (S) and maceration (M) using ethanol, and boiled with distilled-water (B). Total phenolic (TPC) and total flavonoid (TFC) contents were quantified. The three antioxidant and tyrosinase inhibition activities were determined by DPPH, FIC and FTC; and the modified dopachrome methods, respectively. The collagen biosynthesis and the anti-melanogenesis activities were investigated by Sirius-Red and the melanin content assay.

RESULTS

The yields of BG extracts ranged from 1.72% to 9.06%. The BG-SS extract gave the highest TPC and TFC. The BG-HM extract showed the highest antioxidant activities (SC₅₀ of 0.87 ± 0.02 mg/mL, MC₅₀ of 1.83 ± 0.09 mg/mL and LC₅₀ of 0.70 ± 0.06 mg/mL), tyrosinase inhibition activity (IC₅₀ of 0.45 ± 0.23 mg/mL), and anti-melanogenesis activities (72.9 ± 0.08%), whereas the BG-SB extract exhibited the highest stimulation of collagen biosynthesis (18.04 ± 0.03%). All BG extracts at 0.1 mg/mL showed no cytotoxicity on human dermal fibroblasts.

DISCUSSION

The biological activities of BG extracts might be from their phytochemicals, especially phenolic and flavonoid contents.

CONCLUSION

The BG-HB and BG-HM extracts might be promising novel active sources for anti-aging and whitening cosmeceuticals.

Determination of Antiradical Activity, Total Phenolic, and Total Flavonoid Contents of Extracts and Fractions of Langsat (Lansium domesticum Coor.) Seeds

Lansium domesticum Coor. is a fruit species from the Meliaceae family, which is a tropical plant native to Southeast Asia. Local citizens call it langsat, longkong, or duku and have used it as traditional medicine. The seeds of L. domesticum are used as a fever medicine, its bark is used to treat scorpion sting, and its leaves are used to repel mosquitoes. Because of its various uses, it is necessary to explore the antiradical potential of L. domesticum seeds. This study aims to determine the antiradical potential of L. domesticum seeds extract and fractions by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method and to discover compounds that act as antiradical. Lansium domesticum seed powder was macerated with methanol, and then the extract was concentrated using a rotary evaporator and fractionated by n-hexane and ethyl acetate. The antiradical assay was conducted on extract and fractions by using DPPH radicals. Phenolic and flavonoid contents from extract and fractions were also tested. The ethyl acetate fraction obtained strong antiradical potential with an IC50 value of 8.938 � 0.031 �g/mL. Total phenolic and flavonoid contents of ethyl acetate fraction were higher with values ??of 58.25 � 0.501 mgGAE/g sample and 75.123 � 0.175 mgQE/g sample, respectively. Correlation of phenolic and flavonoid contents, which inhibited radicals had R2 values ??of 0.9182 and 0.7658. Ethyl acetate fraction of L. domesticum seeds had very strong antiradical activity. Further isolation is expected to be conducted to discover which compounds are the most responsible as antiradical.

Production of Verbascoside, Isoverbascoside and Phenolic Acids in Callus, Suspension, and Bioreactor Cultures of Verbena officinalis and Biological Properties of Biomass Extracts

Callus, suspension and bioreactor cultures of Verbena officinalis were established, and optimized for biomass growth and production of phenylpropanoid glycosides, phenolic acids, flavonoids and iridoids. All types of cultures were maintained on/in the Murashige and Skoog (MS) media with 1 mg/L BAP and 1 mg/L NAA. The inoculum sizes were optimized in callus and suspension cultures. Moreover, the growth of the culture in two different types of bioreactors-a balloon bioreactor (BB) and a stirred-tank bioreactor (STB) was tested. In methanolic extracts from biomass of all types of in vitro cultures the presence of the same metabolites-verbascoside, isoverbascoside, and six phenolic acids: protocatechuic, chlorogenic, vanillic, caffeic, ferulic and rosmarinic acids was confirmed and quantified by the HPLC-DAD method. In the extracts from lyophilized culture media, no metabolites were found. The main metabolites in biomass extracts were verbascoside and isoverbascoside. Their maximum amounts in g/100 g DW (dry weight) in the tested types of cultures were as follow: 7.25 and 0.61 (callus), 7.06 and 0.48 (suspension), 7.69 and 0.31 (BB), 9.18 and 0.34 (STB). The amounts of phenolic acids were many times lower, max. total content reached of 26.90, 50.72, 19.88, and 36.78 mg/100 g DW, respectively. The highest content of verbascoside and also a high content of isoverbascoside obtained in STB (stirred-tank bioreactor) were 5.3 and 7.8 times higher than in extracts from overground parts of the parent plant. In the extracts from parent plant two iridoids-verbenalin and hastatoside, were also abundant. All investigated biomass extracts and the extracts from parent plant showed the antiproliferative, antioxidant and antibacterial activities. The strongest activities were documented for the cultures maintained in STB. We propose extracts from in vitro cultured biomass of vervain, especially from STB, as a rich source of bioactive metabolites with antiproliferative, antioxidant and antibacterial properties.

Insight into anti-oxidative carbohydrate polymers from medicinal plants: Structure-activity relationships, mechanism of actions and interactions with bovine serum albumin

Recently, research associated with natural anti-oxidants leads to the chemical characterization of many compounds possessing strong anti-oxidant activity. Among these anti-oxidants, naturally occurring carbohydrate polymers containing pectic arabinogalactans esterified with phenolic acids in monomeric and dimeric forms are noteworthy. The presence of highly branched arabinogalactan type II side chains and sugar linked phenolic acid residues have been resolved as important parameters. The anti-oxidant activity of these compounds depend on their ability to convert free radicals into stable by-products and themselves oxidized to more stable and less reactive resonance stabilized radicals. Moreover, these carbohydrate polymers form water soluble stable complexes with protein. Such findings support their applications in a diversity of fields including food industry and pharmacy. This review highlights experimental evidences supporting that the carbohydrate polymers containing phenolic polysaccharides may become promising drug candidate for the prevention of aging and age related diseases.

LC-MS Phytochemical Screening, In Vitro Antioxidant, Antimicrobial and Anticancer Activity of Microalgae Nannochloropsis oculata Extract

Nowadays, marine microalgae are recognized to be a considerably novel and rich origin of bioactive moieties utilized in the sectors of nutraceuticals and pharmaceuticals. In the present study, Nannochloropsis oculata extract (AME) was associated with a wide variety of pharmacological studies such as in vitro antioxidant, antibacterial, and antifungal and anticancer activity (MDA-MB-231) in cancer cells through in vitro models. In the study, the chemical composition and structure of the bioactive compounds found in the AME extract were studied using the LC-MS technique. The results of the anticancer activity showed a decrease in the percentage of cell viability of the MDA-MB-231 cells in a concentration- and time-dependent manner (400 μg/mL at 24 h, 300 μg/mL at 48 h, and 200 μg/mL at 72 h). We have also observed morphological changes in the cells that could be associated with treatment with AME extract. Our observation of the AME extract-treated MDA-MB231 cells under light microscopy showed that when the concentration increased, the number of cells began to decrease. As far as LC-MS analysis is concerned, it showed the presence of the bioactive molecules was terpenoids along with carotenoids, polyphenolic and fatty acids. The result revealed that the AME extract exhibited noteworthy in vitro free radical scavenging potential, with an IC50 value of 52.10 ± 0.85 µg/L in DPPH assay, 122.84 ± 2.32 µg/mL in H2O2 assay and, 96.95 ± 1.68 µg/mL in ABTS assay. The activity was found to be highly significant against bacteria (Gram-positive and negative) and moderately significant against fungal strain with minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC)/minimum fungicidal concentration (MFC) values between 15.63 and 500 µg/mL.