Methyl jasmonate elicitation improves antioxidant and antibacterial activities in Portulaca oleracea

The therapeutic potential of bamboos has acquired global attention. Nonetheless, the biological activities of the plants are rarely considered due to limited available references in Sabah, Malaysia. Furthermore, the drying technique could significantly affect the retention and degradation of nutrients in bamboos. Consequently, the current study investigated five drying methods, namely, sun, shade, microwave, oven, and freeze-drying, of the leaves of six bamboo species, Bambusa multiplex, Bambusa tuldoides, Bambusa vulgaris, Dinochloa sublaevigata, Gigantochloa levis, and Schizostachyum brachycladum. The infused bamboo leaves extracts were analysed for their total phenolic content (TPC) and total flavonoid content (TFC). The antioxidant activities of the samples were determined via the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric reducing antioxidant power (FRAP) assays, whereas their toxicities were evaluated through the brine shrimp lethality assay (BSLA). The chemical constituents of the samples were determined using liquid chromatography–tandem mass spectrometry (LC-MS/MS). The freeze-drying method exhibited the highest phytochemical contents and antioxidant activity yield, excluding the B. vulgaris sample, in which the microwave-dried sample recorded the most antioxidant and phytochemical levels. The TPC and TFC results were within the 2.69 ± 0.01–12.59 ± 0.09 mg gallic acid equivalent (GAE)/g and 0.77 ± 0.01–2.12 ± 0.01 mg quercetin equivalent (QE)/g ranges, respectively. The DPPH and ABTS IC50 (half-maximal inhibitory concentration) were 2.92 ± 0.01–4.73 ± 0.02 and 1.89–0.01 to 3.47 ± 0.00 µg/mL, respectively, indicating high radical scavenging activities. The FRAP values differed significantly between the drying methods, within the 6.40 ± 0.12–36.65 ± 0.09 mg Trolox equivalent (TE)/g range. The phytochemical contents and antioxidant capacities exhibited a moderate correlation, revealing that the TPC and TFC were slightly responsible for the antioxidant activities. The toxicity assessment of the bamboo extracts in the current study demonstrated no toxicity against the BSLA based on the LC50 (lethal concentration 50) analysis at >1000 µg/mL. LC-MS analysis showed that alkaloid and pharmaceutical compounds influence antioxidant activities, as found in previous studies. The acquired information might aid in the development of bamboo leaves as functional food items, such as bamboo tea. They could also be investigated for their medicinal ingredients that can be used in the discovery of potential drugs.

BackgroundGuava (Psidium guajava Linn.) has been traditionally used in the treatment of a wide range of diseases due to its rich content of secondary metabolites.AimThis study was aimed to evaluate the effect of altitude and solvent systems on guava leaves crude extract’s phenolics and flavonoid content, antioxidant, antimicrobial, and toxicity nature.MethodsGuava leaves were collected from three different geographical locations in Nepal while solvents with an increasing polarity index were used for extraction. The yield percentage of extracts was calculated. Total Phenolic Content, Total Flavonoid Content, and antioxidant activity were determined by the Folin-Ciocalteu method, Aluminium chloride colorimetric method, and DPPH (2,2′-Diphenyl-1-picrylhydrazyl) assay respectively. The quantification of fisetin and quercetin was performed using the HPLC with method validation. The antimicrobial activity of the extracts was tested against bacteria and fungus isolated from spoiled fruits and vegetables and identified through 16s and 18s rRNA sequencing. Finally, Brine Shrimp Lethality Assay (BSLA) was used for testing the toxicity of the extracts.ResultsThe phenolic and total flavonoid content was found to be higher in ethanol extract (331.84 mg GAE/g dry extract) and methanol extract (95.53 mg QE/g dry extract) from Kuleshwor respectively. Water extract of guava leaves from Kuleshwor (WGK) did not show significantly different antioxidant activity when compared to methanol and ethanol extracts. Fisetin and quercetin were higher in WGK (1.176 mg/100 g) and (10.967 mg/100 g) dry extract weight respectively. Antibacterial activity against food spoilage bacteria was dose-dependent and found to be highest for all the extracts from different solvents and altitudes at higher concentrations (80 mg/ml). Similarly, methanol and ethanol guava extracts from all locations showed antifungal activity against Geotrichum candidum RIBB-SCM43 and Geotrichum candidum RIBB-SCM44. WGK was found to be non-toxic.ConclusionOur study concludes that the antioxidant and antimicrobial activity of WGK was found to be similar statistically to that of methanol and ethanol extracts of Bishnupur Katti and Mahajidiya. These results suggest the possibility of using water as a sustainable solvent to extract natural antioxidant and antimicrobial compounds which can further be used as natural preservatives to extend the shelf life of fruits and vegetables.

This study sought to assess the leaf extracts of matoa (Pometia pinnata) and pulasan (Nephelium ramboutan-ake) for antimicrobial, antifungal, antioxidant, and cytotoxic activities, besides phytochemical content. Four extracts (hexane, ethyl acetate, ethanol, and water) were obtained from each plant via sequential extraction. The antimicrobial activities were evaluated using colorimetric broth microdilution methods. The antioxidant activities were studied using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric-reducing antioxidant power (FRAP) assays. The cytotoxicity was examined using mouse fibroblasts NIH/3T3 while the phytochemical content was detected using various chemical tests. Among the extracts, only the water extract of matoa and ethyl acetate extract of pulasan exerted bactericidal effects on Bacillus cereus (minimum bactericidal concentration (MBC): 0.63 mg/mL) and Staphylococcus aureus (MBC: 1.25 mg/mL), respectively. In contrast, all extracts, except hexane extract, of both plants exhibited fungicidal effects with minimum fungicidal concentrations of 0.31-1.25 mg/mL. All extracts of matoa leaves displayed higher DPPH radical scavenging activity and FRAP than the extracts of pulasan leaves. Notably, the water extract of matoa showed the lowest half-maximal inhibitory concentration (IC50) value of 9.88 ± 1.70 µg/mL and the highest FRAP value of 6.11 ± 0.51 mmol Fe2+ equivalent/g extract (n=3). These antioxidant activities were significantly correlated (p<0.01) with the amounts of phenolic compounds in the extracts. All extracts of both plants, except water extracts, showed significant toxicities (p<0.05) towards NIH/3T3 cells. Alkaloids, terpenoids, saponins, and glycosides were detected in the leaves of both plants. The matoa and pulasan leaves contained bioactive compounds with antibacterial, antifungal, and antioxidant activities.

Mangifera pajang Kosterm. fruits, commonly known as 'Bambangan,' are rich in natural antioxidants due to their phytochemical constituents and are categorised as an underutilised fruit. This study focused on investigating the effects of different solvents on the extraction yield (EY), mangiferin content (MC), total flavonoids (TF), total phenolics (TP), antioxidant activity, and toxicity of M. pajang fruit extracts (MPFE). The selected solvents included natural deep eutectic solvents (NADES), water, methanol, and ethanol. The extraction of MPFE was performed using ultrasound-assisted extraction with an ultrasonic probe. Antioxidant activities were evaluated using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays. Toxicological assessment was conducted using the brine shrimp lethality assay (BSLA) to determine LC50 values. Overall, NADES proved to be the most efficient solvent for extraction, yielding the highest EY (37.09 ± 2.34%), MC (0.032 ± 0.000 mg/g), TF (0.80 ± 0.01 mg RE/g dry extract), TP (14.94 ± 1.74 mg GAE/g dry extract), and exhibits potent antioxidant activity as measured by DPPH (82.38 ± 0.24%), ABTS (86.37 ± 0.03%), and FRAP (304.57 ± 5.24 mg TE/g dry extract). Moreover, NADES demonstrated non-toxicity in the BSLA (LC50 = 1988.37 µg/mL) of MPFE. These findings suggest that NADES is a suitable solvent for exploring the medicinal potential of M. pajang fruits and their application in therapeutic development.

Passiflora suberosa L. belonging to the family Passifloraceae is an important medicinal plant used in traditional medicinal system in Sri Lanka to treat diabetes, hypertension and skin diseases. We extracted P. suberosa leaves under reflux conditions using different solvents (hexane, chloroform, methanol and water), then subjected to phytochemical screening. Alkaloids, flavonoids and saponins and saponins and anthraquinones were present in hexane and chloroform extracts. Alkaloids, unsaturated sterols, triterpenes, saponins, flavonoids and tannins were observed in both methanol and aqueous extracts. Proanthocyanidins were observed only in the aqueous extract. Hence, aqueous and methanol extracts with most classes of phytochemicals present were subjected to antimicrobial, antioxidant, antihaemolytic activities and Brine shrimp lethality studies. Antibacterial activity and minimum inhibition concentrations were evaluated using three Gram-positive (Bacillus subtilis, Staphylococcus aureus and Enterococcus faecium) and three Gram-negative bacteria (Pseudumonas aeruginosa, Salmonella typhimuriam and Escherichia coli). The results indicated that only the methanol extract of P. suberosa exhibited antibacterial activities against all the strains of Gram-negative and Gram-positive bacterial with stronger activity against Gram-negative bacteria. DPHH (2,2-diphenyl-1-picrylhydrazy) scavenging assay was adopted to evaluate antioxidant properties while antihaemolytic and toxic activities were studied respectively using cow blood and Brine shrimp lethality assay. The IC50 values of the aqueous extract in both antioxidant and antihaemolytic assays were significantly lower than the standard ascorbic acid. Similar results were observed in the Brine shrimp lethality assay. In conclusion both aqueous and methanol extracts of P. suberosa leaves showed the presence of majority of phytochemicals including proanthocyanidins. Antibacterial activity was obtained only for methanol extract with better activity against Gram-negative bacteria. The aqueous extract showed better antioxidant, antihaemolytic and toxic activities than the methanol extract and their respective standards. Further investigations on the chemical composition and possible isolation of active ingredients is warranted.

This study investigated the phytochemical constituents and antioxidant properties of crude extracts of C. argentea at different maturity stages and seasons. Total phenols, flavonoids, and proanthocyanidin content from water, acetone and methanol extracts were evaluated spectrophotometrically. The antioxidant activities were measured using 2,2- diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), Ferric reducing antioxidant power (FRAP) and Total antioxidant capacity (TAC) models. Results showed that the flowering stages in all the solvent extracts gave the highest polyphenolic content with the acetone extract significantly higher than the methanol and aqueous extracts (P < 0.05). The highest value for total polyhenolic content 80.75 ± 4.21 for the first trial and 89.69 ± 2.13 μg/mL in the second trial; while the flavonoids was 874.76 ± 7.87 and 946.19 ± 7.87 μg/mL in the first and second trials respectively; and proanthocyanidin content was 170.00 ± 0 and 100.90 ± 1.29 μg/mL. Overall, the aqueous extracts had the lowest content of all the phytochemicals. The antioxidant activities ranged from low to high at different growth stages of the plant. While low to no activity was observed in the aqueous extracts in all the assays, the methanol extracts of the flowering stages showeds the best activity in the first and second trials with IC50 values of 104.10 ± 8.59 and 120.02 ± 13.37 μg/mL respectively in ABTS. Similar trend was obtained in the DPPH assay with the highest activity in the methanol flowering extract with IC50 of 52.36 ± 0.76 μg/mL (first trial) and 49.36 ± 0.29 μg/mL (second trial). The FRAP and TAC also had the highest activity in the flowering stages in all solvents, but with the acetone extracts having the overall inhibition on both radicals. This study revealed that Celosia argentea phytoconsituents and antioxidant potential can be influenced by physiological and developmental stages of the plant.

The main aim of this study was to determine Total Phenolic Content, Total Flavonoid Content, terpenoid content, steroid content and analyze the antioxidant activity of different leaf extracts of Entada rheedii. Correlation between antioxidant activities and total phenolic content, total flavonoids content, terpenoid content and steroid content were also analyzed. The total phenolic content in E. rheedii hexane, ethyl acetate, methanol, and aqueous leaf extracts were found to be 10.16 mg GAE/g, 24.73 mg GAE/g, 26.11 mg GAE/g, and 24.85 mg GAE/g sample dry weight respectively. The Total flavonoid content of E. rheedii hexane, ethyl acetate, methanol, and aqueous leaf extracts was found to be 8.433 mg QE/g, 8.730 mg QE/g, 8.607 mg QE/g, and 8.545 mg QE/g respectively. Hexane extract showed the highest steroid content at 32.75 g/mL, followed by ethyl acetate extract at 31.37 g/mL. The methanol extract and aqueous extract had the lowest steroid content at 22.2 g/mL and 21.21 g/mL, respectively. Terpenoid content was the highest in hexane extract with 62 mg/100 mg of dry extract, followed by the ethyl acetate extract with 45 mg/100 mg dry extract. The total content of terpenoids in the methanol extract was 25 mg/100 mg dry extract and the total content of terpenoids was lowest in the aqueous extract with 18 mg/100 mg dry extract. In 1-1-diphenyl- 2-picryl hydrazine Free Radical Scavenging (DPPH) Assay, the methanol extract displayed the highest antioxidant activity with an IC50 value of 173.581 μg/mL while the hexane extract showed the lowest activity; with IC50 value of 389.13 μg/mL. Reducing power assay was evaluated and aqueous extract was shown to possess the highest reducing power. Evaluation of total antioxidant capacity by phosphomolybdenum assay indicated that methanol extract had the highest antioxidant capacity. Significant correlations were also found between Total Phenol Content, Total flavonoid Content, and antioxidant activities of different leaf extracts of Entada rheedii.

Spiranthera odoratissima A. St.-Hil (Rutaceae), a shrub whose common name is manacá do Cerrado in Brazilian Portuguese, is about 1-m high and has been used by folk medicine to treat stomachache, kidney and liver infections, headache, rheumatism and as a blood purifier. This study aimed at preparing hexane, ethyl acetate, methanolic, hydroethanolic and aqueous extracts from S. odoratissima leaves, at carrying out preliminary phytochemical screening and at evaluating their in vitro antioxidant and anti-Listeria monocytogenes activities. Antioxidant activity was evaluated by the DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azinobis-3-ethybenzothiazoline-6-sulfonate) and FRAP (ferric reducing antioxidant power) methods. Antibacterial activity was investigated against L. monocytogenes and Minimum Inhibitory Concentration (MIC) values of plant extracts were calculated by the broth microdilution method with the use of 96-well plates. In aqueous, methanolic, hydroethanolic, ethyl acetate and hexane extracts from S. odoratissima leaves, the following classes of compounds were investigated: organic acids, reducing sugars, flavonoids, saponin compounds, coumarin compounds, phenolics, tannins, purine compounds, catechins, flavonol derivatives, sesquiterpene lactones and anthraquinones. All plant extracts, except the hexane one, exhibited high antioxidant activity. Regarding antibacterial activity, the most polar extracts showed high activity against L. monocytogenes; their MIC values ranged between 12.5 and 62.5 µg mL-1, while the hexane one exhibited low activity (MIC = 1000 µg mL-1). In short, extracts from S. odoratissima leaves may be considered promising sources of secondary metabolites with relevant antioxidant and antibacterial activities.

The purpose of this study was to investigate the phytochemical composition and antioxidant activity of 17 edible wild fruits that are widely distributed and consumed in Malawi for pharmacological value exploration. Qualitative phytochemical analysis, total phenolic content, total flavonoid content, ferric reducing antioxidant power (FRAP), total antioxidant activity (TAA), and 1,1‐diphenyl‐2‐picrylhydrazyl radical scavenging activity (DPPH) were performed in aqueous and methanolic fruit extracts. The results showed that the extracts contained alkaloids, saponins, terpenoids, glycosides, coumarins, phenolic compounds, tannins, flavonoids, steroids, and quinones. Piliostigma thonningii had the highest total phenolic content (1675.33 ± 12.34 mg GAEg-1 FW) in methanolic extracts, and Annona senegalensis gave the highest levels of total flavonoid content (649.67 ± 2.08 mg RE g-1 FW) in aqueous extracts. The results of antioxidant activities (FRAP, TAA, and DPPH) varied widely, and the variations were significant (P &lt; 0.05). Thespesia garckeana and Mangifera indica exhibited a high ability to chelate metal cations in methanolic extracts and in aqueous extracts, respectively. DPPH levels were higher in aqueous extracts and ranged from 11.07% to 99.61%. This study provides evidence that the studied edible fruits of Malawi have potential as value‐added products for various treatments of oxidative stress‐associated ailments as they contain more phytochemical constituents. We recommend further studies to determine if the presence of a particular class of phytochemicals would translate into the bioactivity capability of these edible fruits.

The Devil’s tree (Alstonia scholaris (L.) R.Br.), a member of the Apocynaceae family, is recognised in various traditional systems for its efficacy in treating several diseases. In the Mizo traditional medicines of India, the bark extract is utilised as a remedy for bacterial and parasitic infections, among other ailments. To validate the therapeutic claim of the Mizo people, a methanolic extract of the bark was prepared and its chemical composition was analysed. The extract was found to contain alkaloids, carbohydrates, flavonoids, glycosides, phytosterols, saponins, tannins, and reducing sugars. The antioxidant components of the extract were quantified, revealing a phenolic content of 13.563±0.09 mg/g quercetin equivalent, a flavonoid content of 31.64±2.50 mg/g gallic acid equivalent, and a total antioxidant of 10.48±0.84 mg/g ascorbic equivalent. These findings underscore the plant’s cellular protective capacity. Furthermore, the antioxidant activities were assessed using 2,2-diphenyl-1-1-picryldrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. The plant extract exhibited significant antioxidant properties, with a half-maximal inhibitory concentration (IC50) value of 11.01 against free radicals generated from the DPPH reaction. Notably, the extract demonstrated broad-spectrum antibacterial activity against Gram-negative bacteria, including Escherichia coli and Salmonella typhi, as well as Gram-positive species such as Bacillus cereus, Enterococcus faecalis and Staphylococcus aureus. This study establishes A. scholaris as a medicinal plant with promising antimicrobial and pharmacological properties, containing chemical components that can be harnessed for therapeutic purposes.

Polyphenolic profile and biological properties of Arbutus unedo root extracts

ABSTRACTFicus deltoidea Jack (Moraceae) is a well-known medicinal plant used in customary medication among the Malay people to reduce and mend sicknesses such as ulcers, psoriasis, cytotoxicity, cardioprotective, inflammation, jaundice, vitiligo, hemorrhage, diabetes, convulsion, hepatitis, dysentery injuries, wounds, and stiffness. Ficus deltoidea contains a wide variety of bioactive compounds from different phytochemical groups such as alkaloids, phenols, flavonoids, saponins, sterols, terpenes, carbohydrates, and proteins. The genus Ficus has several hundreds of species, which shows excellent therapeutic effects and a wide variety of helpful properties for human welfare. Searching information was collected by using electronic databases including Web of Science, Science Direct, Springer, SciFinder, PubMed, Scopus, Medline, Embase, and Google Scholar. This review is, therefore, an effort to give a detailed survey of the literature on its pharmacognosy, phytochemistry, phytochemical, and pharmacological properties of Ficus and its important species. This summary could be beneficial for future research aiming to exploit the therapeutic potential of Ficus and its useful medicinal species.

Phenolic content, enzyme inhibitory and antioxidative activity potentials of Phlomis nissolii and P. pungens var. pungens

Malaria is the leading cause of morbidity and mortality in African countries. We aimed this study at evaluating the in vitro antiplasmodial, antioxidant, and cytotoxicity activity of Lophira lanceolata extracts. The aqueous and ethanol extracts were obtained by maceration. It tested in vitro the extracts against Plasmodium falciparum 3D7 and multiresistance Dd2. Macrophage cell lines (RAW 264.7 cells) and red blood cells were used for cytotoxicity tests. The antioxidant activity was assessed by 1,1-diphenyl-2-picrylhydrazine (DPPH), hydrogen peroxide (H2O2), nitric oxide (NO) reduction, and ferric reducing antioxidant power (FRAP) scavenging. The in vitro antiplasmodial results showed that the ethanol extract was the most active, with IC50 of 24.51 ± 4.77 µg/mL and 31.86 ± 3.10 µg/mL, respectively, on the resistant Dd2 and sensitive 3D7 strains unlike the aqueous which indicated moderate activity with an IC50 of 51.36 ± 4.86 μg/mL and 56.36 ± 4.27 μg/mL, respectively, on the resistant Dd2 and sensitive (3D7) strains. However, the ethanol extract had the highest activity, with an IC50 of 8.153 g/mL, 1915 g/mL, 30.81 g/mL, and 54.66 g/mL, respectively, for DPPH, H2O2, NO, and FRAP, while the aqueous extract had an IC50 of 6.724, 2387681, 185.7, and 152.0 g/mL, respectively, for DPPH, H2O2, NO, and FRAP. The cytotoxicity test reveals that both extracts do not promote red blood cell haemolysis. They presented weak activity against RAW 264.7 cells and red blood cells. According to these findings, the aqueous and ethanol extracts have antiplasmodial and antioxidant activity but with no cytotoxic effects on red blood cells or RAW cells. However, it will be important to investigate the in vivo antiplasmodial and antioxidant activity of these extracts.

BackgroundNortheast India has a rich resource of herbal plants, and it is essential to validate their therapeutic activity with proper scientific evidence. This study aims to identify active phytocompounds found in the extracts of Eranthemum indicum (E. indicum) and to determine its antioxidative activities and toxicity.ResultsIn vitro free radical scavenging activity of the aqueous extract (AE) and methanol extract (ME) of E. indicum (leaves) was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulfonic-acid (ABTS), ferric reducing antioxidant power (FRAP), and total antioxidant activity (TAC). ME depicted better inhibitory concentration when compared to AE. This indicates the effective extraction capacity of methanol, which is consistent with the fact that ME had a higher polyphenol and flavonoid, resulting in their antioxidative activity. HPTLC analysis using the solvent system of ethyl acetate/methanol/ammonia 28–30% (40:10:10) showed better fingerprinting separation, especially in the ME. Furthermore, DPPH radical solution, when used as a derivatizing agent in HPTLC analysis, confirmed that ME has better in vitro antioxidant activities than AE. GCMS analysis of AE identified 3-beta-hydroxy-5-cholen-24-oic-acid as active compound, while in ME Beta.-l-arabinopyranoside and 2-methyl-3-(3-methyl-but-2-enyl)-2-(4-methyl-pent-3-enyl)-oxetane were identified as the major bioactive compound. Acute toxicological investigations have shown that both E. indicum extracts have a high L.D. 50 value of 1533 mg/kg b.w for AE and 1567 mg/kg b.w for ME making them safe and non-toxic.ConclusionsExtraction and identification of these phytocompounds in the extracts of E. indicum can help us scientifically document its medicinal importance, and its benefit in pharmaceutical industries. Since it showed promising free radical scavenging activity, it can also be a potent antioxidant source.