Total flavonoids content and biochemical screening of the leaves of tropical endemic medicinal plant Merremia borneensis

Investigation of Chemical Constituents and Antioxidant Activity of Biologically Active Plant-Derived Natural Products

The aim of this publication is to present rapid screening methods (visual/colorimetric) that will enable quick identification of the presence of biologically active compounds in aqueous solutions. For this reason, 26 plant extracts obtained by ultrasound-assisted extraction were analysed for the content of these compounds. Higher plants, used as a raw material for extraction, are common in Europe and are easily available. The article proposes a comparison of various protocols for the identification of various compounds, e.g., phenolic compounds (phenols, tannins, anthocyanins, coumarins, flavones, flavonoids), vitamin C, quinones, quinines, resins, glycosides, sugars. Initial characterisation of the composition of plant extracts using fast and inexpensive methods allows you to avoid the use of time-consuming analyses with the use of advanced research equipment. In addition, the antioxidant activity of plant extracts using spectrophotometric methods (DPPH, ABTS, FRAP assay) and quantitative analysis of plant hormones such as abscisic acid, benzoic acid, gibberellic acid, indole acetic acid, jasmonic acid, salicylic acid, zeatin, zeatin riboside, and isipentenyl adenine was performed. The obtained results prove that the applied visual methods show different sensitivity in detecting the sought chemical compounds. Therefore, it is necessary to confirm the presence or absence of bioactive substances and their concentration using modern analytical methods.

Nutraceutical Prospects and Antioxidant Activity of White and Red Water Lily Stem Available in Bangladesh

Generally, the white and red water lily cultivars' stems are consumed as vegetables in Bangladesh. However, data on the nutritional benefits and antioxidant properties of these aquatic plant’s stem are scant. Considering the aforementioned possibilities, the goal of this study was to evaluate the nutritional value, anti-nutritional factors, and antioxidant activity of two common Nymphaea species such as Nymphaea nouchali (white variety), and Nymphaea rubra (red variety) grown in Bangladesh. The proximate analysis and mineral content were determined by following AOAC methods. Crude fiber content was significantly higher in the white lily (19.56±0.68%) compared to the red cultivar (16.24±1.05%). Conversely, the red lily showed a higher value (18.52±1.01%) for ash content than the white species (15.44±0.79%). However, the varieties had no significant differences in moisture, protein, fat, and carbohydrate content. Both stems were rich in essential minerals, whereas Na and Cu were significantly higher in white water lily (WWL); however, the red water lily (RWL) stem possessed significantly copious amounts of K and P. On the other hand, there was no significant difference between two species in the case of Ca, Mg, Fe, and Zn content. The assay showed that the total phenolic contents (mg GAE/g) and total flavonoid contents (mg QE/g) were 16.51±0.05 and 15.48±02, 476±0.1 and 7.846±0.1 in white and red water lily stems respectively. In addition, the anti-nutrient screening revealed that both species were positive for saponin and tannin. Furthermore, the extract of RWL stem showed more antioxidant activity (IC50 value 28.48±0.12µg/ml) against DPPH than WWL (IC50 value 36.67±0.09 µg/ml). Thus, water lily stems can be incorporated into our diet as a potential natural source of antioxidants and vital elements.

Antioxidant and Anti-Inflammatory Activities of Endemic Plants of the Australian Wet Tropics

Plants have been a vital source of natural antioxidants since ancient times. Plants growing under various abiotic stress conditions often produce more defensive secondary metabolites such as phenolics, flavonoids, and terpenoids during adaptation to the environment. Many of these secondary metabolites are known to possess antioxidant and anti-inflammatory properties. This study tested seven plants sourced from the mountaintop areas (above 1000 m elevation) of Mount Lewis National Park (falls under the Wet Tropics of Queensland), Australia, for their antioxidant and anti-inflammatory activities. Of the seven studied plants, hydroethanolic extracts of six plants (Leptospermum wooroonooran, Ceratopetalum hylandii, Linospadix apetiolatus, Garcinia brassii, Litsea granitica, and Polyscias willmottii) showed high 2,2-diphenyl-1-picrylhydrazyl (DPPH)-free radical scavenging activity in a dose-dependent (25–1000 μg/mL) manner. At the highest concentration of 1 mg/mL, the DPPH free radical scavenged percentage varied between 75.4% and 92.3%. Only the species Alyxia orophila was inactive in the DPPH free radical scavenging assay. Pseudo-IC₅₀ values of the extracts’ ferric reducing antioxidant power (FRAP) based on dose-response curves showed a significant positive correlation with total phenolic content. Five out of the seven plants, namely G. brassii, C. hylandii, L. apetiolatus, L. wooroonooran, and A. orophila, showed inhibitory effects on the secretion of proinflammatory cytokines, tumour necrosis factor (TNF), and interleukins (IL)-23 in a lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cells (PBMCs) assay. The results of this study demonstrate the value of tropical mountaintop plants in the biodiscovery of antioxidant and anti-inflammatory lead compounds.

Identification and Characterization of Regulatory Pathways Controlling Dormancy Under Lower Temperature in Alfalfa (Medicago sativa L.)

Alfalfa (Medicago sativa L.), a kind of high-quality perennial legume forage, is widely distributed in the northern regions of China. In recent years, low temperatures have frequently occurred and limited alfalfa productivity and survival in early spring and late fall. However, the underlying molecular mechanisms of alfalfa response to cold tolerance are not well-documented. In this study, dormancy and non-dormancy alfalfa standard varieties were characterized under low-temperature stress. Our analysis revealed that plant height of the dormancy genotype was strongly inhibited by low temperature; flavonoids content, and higher expression of flavonoids biosynthesis genes (chalcone synthase, leucoanthocyanidin dioxygenase, and flavonoid 3'-monooxygenase) may play essential roles in response to low-temperature stress in dormancy genotype alfalfa. Further analyses revealed that receptor-like kinase family genes (such as cysteine-rich RLK10, lectin protein kinase, and S-locus glycoprotein like kinase), RNA and protein synthesis genes (RNA polymerases, ribosomal protein, and protein phosphatase 2C family protein), and proteasome degradation pathway genes (such as F-box family protein, RING/U-box superfamily protein, and zinc finger family protein) also highly upregulated and contributed to cold tolerance phenotype in dormancy genotype alfalfa. This will provide new insights into future studies for cold tolerance in alfalfa and offer new target genes for further functional characterization and genetic improvement of alfalfa.

The insecticidal capacity of ethanol extract from Cascabela peruviana (L.) Lippold against fruit fly

Cascabela peruviana (L.) Lippold (C. peruviana) has been extensively used for its antifungal and antibacterial properties. However, its role in anti-insect is still under investigation. To investigate the ability of the ethanol extract of C. peruviana against insects, we used the fruit fly (Drosophila melanogaster) as a model to gain more insight into the toxic effects of this extract. We found that the ethanol extract from the stem and leaves of C. peruviana was effective against insects and contained polyphenol and flavonoid compounds. C. peruviana could induce mortality of 2^nd-instar larvae and reduce growth and reproduction of fruit flies. Interestingly, the toxicity of C. peruviana extract has been remained to affect the development of the next generation of fruit flies. The locomotor activity and feeding ability of the F1 generation of this insect were significantly reduced by C. peruviana. In addition, flavonoids and polyphenols, as well as saponins and tannins were detected in the ethanol extract of C. peruviana. We assume that the ability of the extract of C. peruviana to control insects may be related to the presence of high levels of these compounds. The findings highlighted that the extract from the leaves of Cascabela peruviana has the potential to be used as an insecticide.

Anti-plasmodial, Cytotoxic and Antioxidant Activities of Selected Ghanaian Medicinal Plants

Malaria affects about half of the world's population. The sub-Saharan African region is the most affected. Plant natural products have been a major source of antimalarial drugs; the first (quinine) and present (artemisinin) antimalarials are of natural product origin. Some secondary metabolites demonstrate adjuvant antioxidant effects and selective activity. The focus of this study was to investigate the anti-plasmodial activity, cytotoxicities and antioxidant properties of eight (8) Ghanaian medicinal plants. The anti-plasmodial activity was determined using the SYBR green assay and the tetrazolium-based colorimetric assay (MTT) was employed to assess cytotoxicity of extracts to human RBCs and HL-60 cells. Antioxidant potential of plant extracts was evaluated using Folin-Ciocalteu and superoxide dismutase assays. Phytochemical contstituents of the plant extracts were also assessed. All the extracts demonstrated anti-plasmodial activities at concentrations <50 μg/ml. Parkia clappertoniana and Terminalia ivorensis elicited the strongest anti-plasmodial activities with 50% inhibitory concentrations (IC₅₀) of 1.13 μg/ml and 0.95 μg/ml, respectively. This is the first report on anti-plasmodial activities of Baphia nitida, Tabernaemontana crassa and Treculia Africana. T. Africana showed moderate anti-plasmodial activity with IC₅₀ value of 6.62 µg/mL. Extracts of P. clappertoniana, T. Africana and T. ivorensis (0.4 mg/mL) showed >50% antioxidant effect (SOD). The extracts were not cytotoxicity towards RBCs at the concentration tested (200 μg/ml) but were weakly cytotoxic to HL-60 cell. Selectivity indices of most of the extracts were greater than 10. Our results suggest that most of the plant extracts have strong anti-plasmodial activity and antioxidant activity which warrants further investigations.

Phytochemical and proximate content of Carapa procera bark and its antimicrobial potential against selected pathogens

Medicinal plants represent a great source of antimicrobial and phytochemical constituents which are increasingly used to treat microbial infections and other ailments such as tuberculosis, anemia, and trachoma. Despite the use of antibiotics, antimicrobial resistance continues to be a world issue, in as much as nutrition. This study investigated the presence of phytochemicals, proximate compositions, and antimicrobial activity of methanolic extract of Carapa procera bark. The bark of Carapa procera was collected, cleaned and air dried for 72 h. The powder obtained was treated with diethyl ether and soaked in methanol (99%) for 72 h to obtain crude extract. The extract was used to test for the presence of phytochemicals and antimicrobial activities. The raw bark was used for proximate analysis. The result showed presence of steroids, tannins and saponins, but no alkaloids present. The 100 mg/mL extract had the highest inhibition zone on all tested organisms from 24.00 ± 0.94 to 26.67 ± 1.18, and 50 mg/mL showed the least (16.67 ± 1.24) on Candida albicans. Staphylococcus aureus showed the lowest minimum inhibition concentration (MIC) of 3.12 mg/mL, whereas the Gram-negative bacteria exhibited variations in their sensitivity with E. coli having the highest MIC of 25 mg/mL. The extract had high MIC (6.25 mg/mL) on Candida albicans than clotrimazole (50 mg/mL). The proximate compositions of Carapa procera were moisture (6.07 ± 0.07%), ash (12.46 ± 0.46%), crude protein (9.54 ± 0.12%), crude fat (1.42 ± 0.06%) and carbohydrate (70.50 ± 0.35%). The energy value was 1413.17 kj. Thus, Carapa procera possesses both antimicrobial and nutritional potentials worth exploring and domesticating for sustainable management and conservation.

Evaluation of Antimicrobial and Anticancer Activities of Selected Medicinal Plants of Himalayas, Pakistan

Medicinal plants are known for their diverse use in the traditional medicine of the Himalayan region of Pakistan. The present study is designed to investigate the anticancer and antimicrobial activities of Prunus cornuta and Quercus&nbsp;semicarpifolia. The anticancer activity was performed using cancerous human cell lines (HepG2, Caco-2, A549, MDA-MB-231, and NCI-H1437 carcinoma cells), while the antimicrobial activity was conducted with the agar-well diffusion method. Furthermore, toxicity studies were performed on alveolar and renal primary epithelial cells. Initially, different extracts were prepared by maceration techniques using n-hexane, chloroform, ethyl acetate, butanol, and methanol. The preliminary phytochemical screening showed the presence of secondary metabolites such as alkaloids, tannins, saponins, flavonoids, glycosides, and quinones. The chloroform extract of P. cornuta (PCC) exhibited significant inhibitory activity against Acinetobacter baumannii (16 mm) and Salmonella enterica (14.5 mm). The A. baumannii and S. enterica strains appeared highly susceptible to n-hexane extract of P. cornuta (PCN) with an antibacterial effect of 15 mm and 15.5 mm, respectively. The results also showed that the methanolic extracts of Quercus semecarpifolia (QSM) exhibited considerable antibacterial inhibitory activity in A. baumannii (18 mm), Escherichia coli (15 mm). The QSN and QSE extracts also showed good inhibition in A. baumannii with a 16 mm zone of inhibition. The Rhizopus oryzae strain has shown remarkable mycelial inhibition by PCM and QSN with 16 mm and 21 mm inhibition, respectively. Furthermore, the extracts of P. cornuta and Q. semicarpifolia exhibited prominent growth inhibition of breast (MDA-MB-231) and lung (A549) carcinoma cells with 19-30% and 22-39% cell viabilities, respectively. The gut cell line survival was also significantly inhibited by Q. semicarpifolia (24-34%). The findings of this study provide valuable information for the future development of new antibacterial and anticancer medicinal agents from P. cornuta and Q. semicarpifolia extracts.

Evaluation of in vitro antioxidant activity of okra mucilage and its antidiabetic and antihyperlipidemic effect in alloxan-induced diabetic mice

Okra (Abelmoschus esculentus) is a traditionally important vegetable herb used to treat numerous illnesses, including diabetes mellitus, in many rural parts of Bangladesh and the South Asian subcontinent. However, the scientific evidence for the aforementioned properties has not been adequately validated. Hence, the aim of this study was to explore the antidiabetic, antilipidemic activity of okra mucilage powder, and to compare its effectiveness with the isolated peel-seed of okra after mucilage extraction in Swiss albino mice. After extraction, both mucilage and peel-seed were made into powder. In addition, crude protein, mineral contents, and in vitro antioxidant activity of mucilage and peel-seed powder were assessed. After acute toxicity test, methanolic extracts of both powders were administered to alloxan-induced diabetic mice for 3 weeks. Blood glucose levels were assessed weekly. Finally, blood samples were collected on day 21 to estimate blood glucose level, total protein (TP), and lipid profile levels. Okra mucilage powder showed less amount of protein, calcium, magnesium, phosphorus, potassium, sodium, and iron compared with peel-seed powder. In terms of antioxidant activity, the IC50 value and total phenolic content were found higher in okra mucilage powder in contrast to peel-seed powder. However, total flavonoid content was higher in peel-seed powder than mucilage powder. Three-week administration of mucilage and peel-seed suspensions at a dose of 150 mg/kg and 200 mg/kg significantly (p < .05) reversed the abnormal changes of bodyweights, water consumption, feed consumption, and fasting blood glucose levels of diabetic subjects. Cholesterol, triglycerides, low-density lipoproteins, high-density lipoproteins, and total protein were found to be significantly (p < .05) improved after mucilage and peel-seed treatment. Thus, Okra can be recommended as a potential source of antidiabetic drug candidate for the effective management of diabetes mellitus and its complications.

Engineered Nanomaterials Suppress the Soft Rot Disease (Rhizopus stolonifer) and Slow Down the Loss of Nutrient in Sweet Potato

About 45% of the world’s fruit and vegetables are wasted, resulting in postharvest losses and contributing to economic losses ranging from $10 billion to $100 billion worldwide. Soft rot disease caused by Rhizopus stolonifer leads to postharvest storage losses of sweet potatoes. Nanoscience stands as a new tool in our arsenal against these mounting challenges that will restrict efforts to achieve and maintain global food security. In this study, three nanomaterials (NMs) namely C₆₀, CuO, and TiO₂ were evaluated for their potential application in the restriction of Rhizopus soft rot disease in two cultivars of sweet potato (Y25, J26). CuO NM exhibited a better antifungal effect than C₆₀ and TiO₂ NMs. The contents of three important hormones, indolepropionic acid (IPA), gibberellic acid 3 (GA-3), and indole-3-acetic acid (IAA) in the infected J26 sweet potato treated with 50 mg/L CuO NM were significantly higher than those of the control by 14.5%, 10.8%, and 24.1%. CuO and C₆₀ NMs promoted antioxidants in both cultivars of sweet potato. Overall, CuO NM at 50 mg/L exhibited the best antifungal properties, followed by TiO₂ NM and C₆₀ NM, and these results were further confirmed through scanning electron microscope (SEM) analysis. The use of CuO NMs as an antifungal agent in the prevention of Rhizopus stolonifer infections in sweet potatoes could greatly reduce postharvest storage and delivery losses.

Biochemical Profiling and Elucidation of Biological Activities of Beta vulgaris L. Leaves and Roots Extracts

RESEARCH BACKGROUND

Red beet (Beta vulgaris L.) is commercially grown in Punjab and Khyber Pakhtunkhwa (KPK) regions while cultivated as vegetable in Baluchistan and Sindh regions of Pakistan. It is well known for its health-promoting role in several clinical and pathologic outcome due to abundance of betalains and other bioactive compounds. The purpose of study was to interpret bioactivity of of B. vulgaris leaves (BvLM) and roots (BvRM) extracts for finding natural cure of neurodegenerative diseases (NDs).

EXPERIMENTAL APPROACH

BvLM and BvRM extracts were evaluated for phytochemical composition, antioxidant, anti-inflammatory and anticholinesterase potential using standard protocols with modifications.

RESULTS

Phytochemicals analysis of BvLM and BvRM extracts depicted the presence of flavonoids, phenols, alkaloids, saponins and glycosides. The IC50 values for free radical scavenging activity for BvRM and BvLM showed that BvLM (DPPH: 2.20 ± 0.72 μg/mL,H 2 O 2 : 0.0519 ± 1.02 μg/mL) is more significant as compared to BvRM (DPPH: 2.312 ± 0.72 μg/mL,H 2 O 2 : 2.668 ± 0.49 μg/mL). BvLM showed significant protection against heat induced hemolysis of HRBCs and protein denaturation (2.322 ± 0.1 > 2.324 ± 0.06 μg/mL) as compared to BvRM (8.572 ± 0.2 > 50.18 ± 1.0 μg/mL). Both extracts found to exhibit strong inhibitory potential against acetylcholinesterase enzyme.

DISCUSSION/CONCLUSION

Our study highlighted B. vulagris extracts as rich and nutritious source of antioxidants, anti-inflammatory and cholinesterase inhibitors that could be helpful in preventing and treating neurodegenerative disorders (NDs). In consideration of multifactorial and complex etiology of NDs, BvLM and BvRM extracts would be apt candidates for development of therapeutic strategy for management of multiple cognitive disorders.

Kinetic Behaviour of Pancreatic Lipase Inhibition by Ultrasonicated A. malaccensis and A. subintegra Leaves of Different Particle Sizes

Gallic acid and quercetin equivalent were determined in the crude extract of matured leaves Aquilaria malaccensis and Aquilaria subintegra. The leaves of both Aquilaria species were dried at 60 °C for 24 hours, ground and sieved into particle size of 250, 300, 400, 500, and 1000 µm. Then, each particle size of leaves was soaked in distilled water with a ratio of 1:100 (w/v) for 24 hours and undergoes the pre-treatment method by using ultrasonicator (37 kHz), at the temperature of 60 °C for 30 minutes. The crude extracts were obtained after about 4 hours of hydrodistillation process. The highest concentration of gallic acid and quercetin equivalent was determined in the crude extract from the particle size of 250 µm. The kinetics of pancreatic lipase inhibition was further studied based using the Lineweaver-Burk plot, wherein the concentration of p-NPP as the substrate and pancreatic lipase were varied. Based on the formation of the lines in the plot, the crude leaves extract of both Aquilaria species exhibit the mixed-inhibition on pancreatic lipase, which indicates that in the reaction, the inhibitors were not only attached to the free pancreatic lipase, but also to the pancreatic lipase-(p-NPP) complex. The reaction mechanism was similar to non-competitive inhibition; however the value of dissociation constant, Ki, for both inhibition pathways was different. The inhibition shows an increment in Michaelis-Menten constant (Km) and a reduction in the maximum pancreatic lipase activity (Vm) compared to the reaction without Aquilaria spp. crude extracts (control). This proved that the inhibition occurred in this reaction. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).  

In silico and in vitro approaches to evaluate the bioactivity of Cassia auriculata L extracts

The present study is an attempt to evaluate the in vitro anti-inflammatory and in silico anticancer potentials of the plant Cassia auriculata (CA). The aerial parts of CA were subjected to solvent extraction, and the extracts were fractionised by gas chromatography and mass spectrometry analysis for its phytochemical content. The antiinflammatory activity of the extracts were confirmed by the IC50 value of 125.02 µg/ml for red blood cell membrane stabilisation and 195.7 µg/ml for inhibition of protein denaturation activity. The interaction of bioactive compounds of CA ethanol extract with target protein was predicted through molecular docking studies, serine/threonine-protein kinase B (AKT1), responsible for development and progression of lung cancer using AutoDock tools. Extensive studies have been carried out on a range of kinase inhibitors targeting Akt, but obtaining promising results is a challenge yet due to its toxicity and resistance issues. Yohimbine, undecanoic acid 10-methyl-ethyl ester and chrysin significantly bind to the target protein with least binding energy. Hence, the present paper establishes the anti-inflammatory and anticancer capacities of CA ethanol extract as an alternative to the existing therapeutic approach to inflammation and cancer through a systematic in vitro and in silico approaches supplementing the findings.

Optimization of the Ultrasonic-Assisted Extraction of Bioactive Flavonoids from Ampelopsis grossedentata and Subsequent Separation and Purification of Two Flavonoid Aglycones by High-Speed Counter-Current Chromatography

The fermented leaf of Ampelopsis grossedentata has been used as a beverage and folk medicine called "vine tea" in the southern region of China. In this paper, the optimum extraction conditions for the maximum recovery amounts of total flavonoids (TF), dihydromyricetin (DMY), myricitrin (MYG) and myricetin (MY) from natural Ampelopsis grossedentata leaves subjected to ultrasonic-assisted extraction (UAE) were determined and optimized by using response surface methodology. The method was employed by the Box-Behnken design (BBD) and Derringer's desirability function using methanol concentration, extraction time, liquid/solid ratio as factors and the contents of TF, DMY, MYG and MY as responses. The obtained optimum UAE conditions were as follows: a solvent of 80.87% methanol, an extraction time of 31.98 min and a liquid/solid ratio of 41.64:1 mL/g. Through analysis of the response surface, it implied that methanol concentration and the liquid/solid ratio had significant effects on TF, DMY, MYG and MY yields, whereas extraction time had relatively little effects. The established extraction and analytical methods were successfully applied to determine the contents of the total flavonoids and three individual flavonoids in 10 batches of the leaf samples of A. grossedentata from three counties in Fujian Province, China. The results suggested the variability in the quality of A. grossedentata leaves from different origins. In addition, high purities of dihydromyricetin and myricetin were simultaneously separated and purified from the extract subjected to optimized UAE, by high-speed counter-current chromatography using a solvent system of N-hexane-ethyl acetate-methanol-water (1:3:2:4; v/v/v/v). In a single operation, 200 mg of the extract were separated to yield 86.46 mg of dihydromyricetin and 3.61 mg of myricetin with the purity of 95.03% and 99.21%, respectively. The results would be beneficial for further exploiting the herbal products and controlling the quality of the herb and its derived products.