Phytochemicals, antioxidant activity, and cyto-toxicity of five Kalanchoe Species

The aim of this research was to assay the phenolic and flavonoid content of ethanolic, methanolic and water extracts of Azilia eryngioides and its related antimicrobial and antioxidant activity. Total phenolic, flavonoid content, DPPH radical scavenging activity and beta carotene linoleic acid of extracts were spectrophotometrically determined. The antimicrobial activity was determined by micro broth dilution assay. The total phenolic content was measured in highest amount in Azilia eryngioides ethanolic (79.32 mg GAC/g) and methanolic extracts (64.23 mg GAC/g), respectively. The antioxidant activity was higher in Azilia eryngioides ethanolic extract. The antimicrobial evaluation exhibited that the ethanolic extract had the best antimicrobial activity than that of two other extracts. This study has been demonstrated the positive correlation between the total phenolic content, antioxidant and antimicrobial activities in Azilia eryngioides ethanolic extract.

This study evaluated Moringa oleifera extracts from two locations in Niger Delta for in vitro anti-cholinesterase and antioxidant activities. Methanolic, aqueous and ethanolic extracts of Moringa oleifera were evaluated for inhibition of acetylcholinesterase (AChE) activity, antioxidant properties, and total phenolic and flavonoid contents using standard procedures. M. oleifera extracts possessed significant and concentration dependent AChE inhibitory activity for methanolic, aqueous, and ethanolic extracts. For the most potent extracts, the percentage AChE inhibition/IC50 (µg/mL) values were Moringa oleifera root methanolic extracts (MORME): ~80%/0.00845; Moringa oleifera root ethanolic extract 1 (MOREE1): ~90%/0.0563; Moringa oleifera root ethanolic extract 2 (MOREE2): ~70%/0.00175; and Moringa oleifera bark ethanolic extract (MOBEE): ~70%/0.0173. The descending order of AChE inhibitory potency of plant parts were: root > bark > leaf > flowers > seed. All M. oleifera methanolic extracts at a concentration of 1000 µg/mL displayed significant (p < 0.05–0.001) DPPH radical scavenging activity, with values of ~20–50% of that of ascorbic acid. The total phenolic content and total flavonoid content (TPC/TFC) of MORME, Moringa Oju bark methanolic extract (MOBME), MOREE1, MOREE2 and Moringa leaf ethanolic leaf extract (MLEE) were (287/254), (212/113), (223/185), (203/343) and (201/102) mg gallic acid equivalents/g and quercetin equivalents/g, respectively. There was an inverse correlation between plant extract AChE inhibition and total phenolic (p < 0.0001) and total flavonoid contents (p < 0.0012). In summary, this study revealed 5 of 19 extracts of M. oleifera that have potent in vitro anti-cholinesterase and antioxidant activities.

The hawthorn Crataegus mexicana is a traditional Mexican fruit with properties that make this fruit useful for the treatment of many ailments, including diseases of the respiratory and urinary tract. This paper reports the antioxidant capacity of the n-hexane, dichloromethane, ethyl acetate, acetone, ethanol and methanol extracts of C. mexicana. Samples were evaluated for total phenolic and carotenoid contents, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging, the inhibition of the formation of thiobarbituric acid reactive species (TBARS) and the neutralization of the cation-radical 2,2´-azino-bis(3ethyl benzothiazoline-6-sulfonic acid) diammonium salt (ABTS). The total phenolic content was 2.65 ± 0.23 mg of gallic acid equivalents per gram, and the carotenoid content was 26.4 ± 0.02 µg/g in dry hawthorn skin. The most active extract in scavenging DPPH radicals and inhibiting TBARS formation was the acetone extract, with activities of 21.9 ± 0.15 and 13.27 ± 0.70%, respectively, at 10 mg/L. The extracts were compared for activity against ascorbic acid, caffeic acid, α- tocopherol and quercetin. The acetone extract was the most active, with an IC50 value of 15.2 mg/L in DPPH and 17.7 mg/L in TBARS. A high correlation was observed between the results for TBARS and DPPH. These results demonstrate the potential nutritional and antioxidant value of this Mexican fruit.

Alzheimer’s disease (AD) is a neurodegenerative disorder, which is the most common cause of dementia. This disease commonly occurs in elderly people. The increase in life expectancy means that that the number of people suffering from AD is expected to rise each year if there is no effective treatment found. The relation of cholinesterase and oxidative stress to Alzheimer’s disease has been reported. In our previous study, we have investigated the potency of the ethanolic extract of Cassia moschata leaves as an anticholinesterase. The current study aimed to investigate the antioxidant and anticholinesterase properties of the ethanolic and aqueous extracts of C. moschata as well as to determine the total phenolic content (TPC). Two different methods were used to evaluate the antioxidant activity by 2,2-diphenyl-1-picryl hydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. The anticholinesterase assay was carried out against acetylcholinesterase (AChE) according to the modified Ellman’s method. The TPC was determined by a colorimetric method using Folin-Ciocalteu’s phenol reagent, and employing gallic acid as a reference. The ethanolic and aqueous extracts of C. moschata demonstrated antioxidant activity in both DPPH and ABTS assays. There were statistically significant differences in the IC50 values of the ethanolic and aqueous extracts in both DPPH and ABTS assays. The aqueous extract exhibited a lower IC50 value compared to the ethanolic extract. The IC50 value for the aqueous extract was 36.46 µg/mL in the DPPH assay, and 10.61 µg/mL in the ABTS method compared to IC50 38.74 µg/mL and 17.17 µg/mL for the ethanolic extract, respectively. Meanwhile, the ethanolic extract showed higher potency as anticholinesterase with the IC50 value of 44.43 µg/mL compared to the aqueous extract with an IC50 value of 114.60 µg/mL. The TPC measurement revealed that the aqueous extract has a higher amount of phenolic than the ethanolic extract. These data suggest that the aqueous extract from the leaves of C. moschata has a higher ability to scavenge free radicals compared to the ethanolic extract, which also contains a higher amount of phenolic compounds. However, the high content of phenolic compounds in the aqueous extract did not correspond to the anticholinesterase activity. The presence of non-phenolic compounds may also contribute to the anticholinesterase activity in the ethanolic extract.

Investigation of antioxidant and antibacterial effects of citrus fruits peels extracts using different extracting agents: Phytochemical analysis with in silico studies

Characterization, antioxidant, and antimicrobial activity of two sage species' organic and aqueous extracts from Morocco's Middle Atlas

Phytochemical analysis of C. alatavicus revealed the presence of phenols, flavonoids, anthocyanins, carotenoids, amino acids and carbohydrates. The flavonoid, amino acids and carotenoid contents were higher in aerial part (1.50%, 7.49% and 9.78mg%, respectively) than in bulb (0.43%, 3.88% and 0.91 mg%, respectively). Total phenolic content (TPC), total antioxidant (TAA), 2.2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and antibacterial activities of water, methanol, ethanol and dichloromethane extracts from aerial part and bulb were tested. TPC ranged from 13.63 to 72.29 mg gallic acid equivalents (GAE)/g extract. The maximum TAA were observed in ethanol (61.34%) and methanol extracts (46.13%) from aerial part with a high TPC (72.29 and 62.37 mgGAE/g extract, respectively). Ethanol extracts from aerial part and bulb had good scavenger of DPPH radicals (65.5% and 54.08%, respectively) with an IC50 387 and 447 µg/ml. Ethanol extract from aerial part was most effective against gram-positive bacterial strains S. aureus, B. subtilis and B. cereus. Biological activities of the extracts were correlated with the TPC. It can be deduced that ethanol and methnol extracts of C. alatavicus contains useful potent bioactive compounds with antioxidant and antimicrobial activities.

BackgroundRosemary (Rosmarinus officinalis) is a commonly used culinary herb with great potential applications in the pharmaceutical, food, and cosmetics industries because of its reported bioactive phytochemicals and antioxidant properties. The purpose of the study was to investigate the effect of seasonal variations in different agro-ecological zones (AEZs) on the phytochemical content and corresponding antioxidant activities of R. officinalis, to ascertain the best growth period at which the plant possesses the highest phytochemical components and most potent antioxidant property. The study also aimed at comparing different extraction solvents to establish the best extraction system for the bioactive compounds.MethodsThe leaves of R. officinalis were harvested from six purposively selected sites in four agro-ecological zones of Kiambu County, Kenya both in the wet and the dry seasons. Phytochemicals were extracted in 80% methanol, 80% ethanol, and distilled water. Total phenolic content (TPC), total flavonoids content (TFC), and total tannins content (TTC) were measured spectrophotometrically as gallic acid equivalent (GAE), rutin equivalent (RUTE) and tannic acid equivalent (TAE), respectively. The antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP). The 80% ethanolic solvent was used to compare the phytochemical content and corresponding antioxidant activities of R. officinalis leaf samples collected from two consecutive seasons in different agro-ecological zones.ResultsThe solvents showed no significant difference (P > 0.05) in TPC with ethanol repotting the highest followed by methanol and water ranging from 39.71 ± 6.77, 24.91 ± 5.15 and 24.91 ± 7.30 (mg/g GAE), respectively. The aqueous TFC (117.22 ± 3.64 mg/g RUTE) was the highest followed by ethanolic and methanolic with 34.72 ± 2.13 and 16.86 ± 2.80 mg/g RUTE, respectively. The TTC of water, methanol, and ethanol extracts were; 19.88 ± 4.59, 15.02 ± 1.25, and 4.27 ± 1.48 mg/g TAE, respectively. The DPPH activity between methanol and ethanol extracts showed no significant difference. The FRAP activity also showed no significant difference (P > 0.05) among the three solvents. There were significant differences between the wet and dry seasons in the phytochemical content. There was no recorded significant difference in the DPPH activity between the dry and wet season in all AEZs. FRAP was significantly higher in the dry season than the wet season for R. officinalis leaves harvested in all agro-agroecological zones except Thika. There were significant differences in phytochemical content and antioxidant activity between the agro-ecologicalzones (p < 0.05) except for the TFC.ConclusionsThe data obtained from this study demonstrated that hydro-alcoholic /methanolic and aqueous maceration systems extracted bioactive compounds from R. officinalis with high potential for applications in industries. The R. officinalis from different agro-ecological zones contained variable phytochemical composition, suggesting that geographical location and climatic conditions influence the biosynthesis and accumulation of secondary metabolites and other bioactive compounds. The data provided in this study will be crucial for processors to select the optimal harvesting season for the extraction of desired bioactive compounds from Rosmarinus officinalis.

Introduction and Aim: Citrus fruits are rich in polyphenolic compounds. The conventional medical system has utilized the fruit’s entire composition including the peel for its diverse biological functions. With this, the study aimed to assess and compare the phytochemical, in-vitro antioxidant analysis as well as polyphenol and flavonoid content of Citrus maxima juice, aqueous and ethanolic extracts of its pulp and peel. Materials and Methods: Qualitative phytochemical screening, total phenolic content and total flavonoid content and different in-vitro antioxidant assays like total antioxidant capacity (TAC), Ferric reducing antioxidant power assay (FRAP), 2,2-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging assay were carried out to evaluate the in-vitro antioxidant potential in the juice, aqueous and ethanolic extract of pulp and peel of C. maxima. Gas chromatography–Mass spectrometry (GC–MS) analysis was performed in the peel ethanolic extract to identify the compounds present. Results: Preliminary phytochemical analysis revealed the presence of triterpenoids and steroids, glycosides, alkaloids, flavonoids, carbohydrates and vitamin C in all the C. maxima crude extracts. Tannins were present only in pulp of ethanol extract and in both aqueous and ethanol extracts of peel. Resins were present in the juice and ethanol extract of pulp and peel. The total phenol and total flavonoid content was comparatively higher in ethanolic extracts of peel. All the extracts showed dose-dependent free radical scavenging activity. The reducing potential of the C.maxima extractives increased with the increase in its concentration. GC-MS analysis of ethanolic peel extract identified key constituents with pharmacological effects. The ethanolic peel extract showed good antioxidant activity and free radical scavenging activity when compared to other extracts. Conclusion: The results indicated that ethanolic peel extract of Citrus maxima revealed the highest presence of polyphenolic compounds, which are secondary plant metabolites with potential antioxidant activity.

Objective: The work is aimed to evaluate the health beneficial properties of (Beta vulgaris) Beetroot. Beetroot ranks among the 10 most powerful vegetable as a natural antioxidant and has a potential source of natural food colourant. The present work is therefore organized to evaluate the Total Phenolic Content (TPC), Antioxidant activity and Antibacterial activity of the Ethanolic and Methanolic extracts of Beetroot.Methods: In the present work the Total Phenolic Content was determined by using Folin-Ciocalteu reagent method of the Ethanolic and Methanolic extracts of Beetroot (Beta vulgaris). The antioxidant scavenging activity of these extracts was determined by applying three different assay methods: (1) (1, 1-diphenyl-2-picryl hydrazyl) DPPH method, (2) Ferric thiocyanate (FTC) method and (3) Thiobarbituric acid (TBA). The antibacterial test was examined against gram positive (B. subtilis, S. aureus) and gram negative (E. coli, S. dysenteriae) bacterial strains.Results: In the present work the Methanolic extract showed greater TPC value 394.8 mg/g GAE than the Ethanolic extract 316.8 mg/g GAE. A correlation between antiradical capacities of the extracts with TPC value was clearly observed. The Methanolic extract was found to be most effective in all the methods. 50% scavenging power of the Methanolic and Ethanolic extracts were (0.129 mg/ml and 0.254 mg/ml) in DPPH method respectively. Moreover, in TBA and FTC method, both the extracts of Beetroot exhibited strong percentage inhibition ranging from 49%-62%. The results of the antibacterial test indicated that the Ethanolic and Methanolic extracts of Beetroot are significantly effective, both in Gram-negative (E. coli, S. dysenteriae) and in Gram-positive (B. subtilis, S. aureus) bacterium.Conclusion: Thus, from the above experimental observations, it can be clearly stated that the Beetroot is a promising source of natural antioxidant and antibacterial agent and definitely provides an alternative towards synthetic antioxidant because of its beneficial properties.

Medicinal plants have been used for therapeutic purposes and have shown important biological properties. This study aimed to evaluate for the first time the antioxidant activities, total flavonoid, and total phenolic contents of Lavandula mairei Humbert. The ethanol, methanol, ethyl-acetate, and water extracts were used for this purpose. The antioxidant activities were assessed in vitro by free radical scavenging activity against 2,2-diphenyl-1-picrylhydrzyl (DPPH), ferric reducing antioxidant power (FRAP), and total antioxidant capacity (TAC). The total flavonoid and phenolic contents were determined spectrophotometrically with gallic acid and Quercetin as standards. In either Soxhlet or maceration methods, the flavonoids and the total phenolic contents were significantly higher in the methanolic extract (P<0.05) compared to other extracts. The total flavonoid content of L. mairei ranged between 119 and 224.6 mg QE/g DW for Soxhlet extracts and from 111.8 to 148.51 mg QE/g DW for maceration extracts. While the total phenolic content was between 35.12 and 99.37 mg GAE/g DW for Soxhlet extracts and 27.63 to 58.99 mg GAE/g DW for maceration extracts. In either the Soxhlet or maceration method, the highest total antioxidant capacity (TAC) was obtained using the ethanolic extract, while the aqueous extract had the highest antioxidant activity for DPPH and FRAP assays. These results showed that Lavandula mairei Humbert has great potential to be a promising candidate for natural plant sources of antioxidants.

Sea buckthorn pomace (SBP) is a by-product of sea buckthorn processing that is rich in bioactive compounds. In this study, different active ingredients were extracted by using different solvents (water, methanol, ethanol, glycerol, ethyl acetate, and petroleum ether) combined with an ultrasonic assisted method. The correlation between the active ingredients and antioxidant properties of the extract was studied, which provided a research basis for the comprehensive utilization of SBP. This study revealed that the 75% ethanol extract had the highest total phenolic content (TPC) of 42.86 ± 0.73 mg GAE/g, while the 75% glycerol extract had the highest total flavonoid content (TFC) of 25.52 ± 1.35 mg RTE/g. The ethanol extract exhibited the strongest antioxidant activity at the same concentration compared with other solvents. The antioxidant activity of the ethanol, methanol, and glycerol extracts increased in a concentration-dependent manner. Thirteen phenolic compounds were detected in the SBP extracts using UPLC-MS/MS analysis. Notably, the 75% glycerol extract contained the highest concentration of all identified phenolic compounds, with rutin (192.21 ± 8.19 μg/g), epigallocatechin (105.49 ± 0.69 μg/g), and protocatechuic acid (27.9 ± 2.38 μg/g) being the most abundant. Flavonols were found to be the main phenolic substances in SBP. A strong correlation was observed between TPC and the antioxidant activities of SBP extracts. In conclusion, the choice of solvent significantly influences the active compounds and antioxidant activities of SBP extracts. SBP extracts are a valuable source of natural phenolics and antioxidants.

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.

Natural antioxidants can be obtained from fruit, vegetables and plants, because they contain the largest compounds, namely phenolic compounds. Phenolic compounds are the largest group of compounds that function as natural antioxidants in plants. One plant that contains a lot of antioxidants is found in the cherry plant (Muntingia calabura L.). This study aims to determine the total phenolic content and antioxidant activity of the maceration and ultrasonic extraction methods of ethanol extract, ethyl acetate of cherry leaves (Muntingia calabura L.). Extraction of cherry leaves was carried out using maceration and ultrasonic methods using ethyl acetate solvent. The thick ethyl acetate and ethanol extracts of cherry leaves were measured for total phenolic content and antioxidant activity. The results of maceration extraction with ethanol solvent had a content of 58.498 mgGAE/g and ethyl acetate had a content of 58.820 mgGAE/g. The results of ultrasonic extraction with ethanol solvent had a content of 56.118 mgGAE/g and ethyl acetate had a content of 51.463 mgGAE/g. The total phenolic content of ethanol and ethyl acetate extracts of cherry leaves from the maceration and ultrasonic methods had significant differences. Ethanol and ethyl acetate extracts of cherry leaves using the maceration extraction method had antioxidant activity levels of 36,639 ppm and 39,361 ppm, while the ultrasonic method had antioxidant activity levels of 35,268 ppm and 39,179 ppm respectively. The antioxidant activity of ethanol and ethyl acetate extracts of cherry leaves from maceration and ultrasonic extraction methods has significant differences.

In the Philippines,Cycasspp. are found in Luzon Island particularly in Pampanga, Batangas, Bataan and Isabela provinces.. In this study, the bioactive potentials of the crude methanolic, ethanolic, ethyl acetate and chloroform leaf extracts ofCycas riuminianaPorte ex Regel were investigated. Based on the results of the four solvents used, the best extraction solvent for the phytochemicals is ethanol, followed by methanol, ethyl acetate and chloroform. The ethanolic and methanolic leaf extracts showed comparable antioxidant activity. The chloroform and ethyl acetate extracts also have comparable antioxidant activity but significantly lower than both methanolic and ethanolic extracts. However the greatest antimicrobial activity was exhibited by the ethyl acetate extract, followed by chloroform, methanolic and ethanolic extracts. The variation and similarity in the antioxidant and antimicrobial activities of the different extracts can be attributed to different mechanisms of interactions, namely, independent joint action, additive, synergistic, competitive or antagonistic interactions, among the bioactive compounds present in the crude extracts. Further studies are needed to elucidate the structure of the different phytochemicals present in the leaf extracts of Arayat Pitogo (C. riuminianaPorte ex Regel) and the specific mechanisms of interaction among these phytochemicals. SUMMARY The extracts were tested for the presence (trace, moderate or abundant amounts) of flavonoids, saponins, tannins, triterpenes, alkaloids, sterols and glycosides. The ethanolic extract was positive for all phytochemicals screened with sterols, flavonoids, glycosides and tannins being abundant, alkaloids being moderate and triterpenes and saponins in trace amounts. The methanolic extract was also positive for all constituents but in trace amounts, except for flavonoids which were abundant. The ethyl acetate extract contained abundant sterols, moderate alkaloids and trace amounts of saponins, glycosides and tannins. Finally, the chloroform extract contained abundant sterols, and trace amounts of alkaloids, saponins and glycosides. The radical scavenging assay revealed that the highest percent inhibition was obtained for the ethanolic leaf extract (60.53±0.7801%), followed by methanolic extract (59.92±3.160%), chloroform extract (50.17±4.779%) and ethyl acetate extract (47.25±3.759%). In terms of antibacterial activity, the ethyl acetate extract registered the highest inhibition against the three test organisms, namely,Staphylococcus aureus, Bacillus subtilisandEscherichia coli. The chloroform extract inhibitedS. aureusandB. subtilis. The methanol extract inhibitedS. aureusonly. Finally, the ethanolic extract failed to inhibit any of the test organisms despite its abundant phytochemicals and high antioxidant activity. In terms of antifungal activity, the different extracts inhibitedCandida albicanswith the ethyl acetate and chloroform extracts showing a high degree of inhibition followed by the methanolic and ethanolic extracts. However, none of the extracts showed any bioactivity againstAspergillus niger.