Guava Leaf Essential Oil as a Potent Antioxidant and Anticancer Agent: Validated through Experimental and Computational Study.

Several drugs now employed in cancer therapy were discovered as a result of anticancer drug research based on natural products. Here, we reported the in vitro antioxidant and anticancer activity followed by in silico anticancer and estrogen-like activity of Psidium guajava L. essential oil against ER-α receptors which lead to potential inhibitory action against breast cancer pathways. METHODS: The bioactive compounds in guava essential oil were screened using gas chromatography-mass spectrometry (GC-MS). Similarly, the antioxidant properties of the extracted oil were evaluated using 2,2-Diphenyl-1-picrylhydrazyl scavenging assay. Furthermore, the in vitro anticancer activity of guava oil was observed through the MTT assay and an in silico molecular docking experiment was also carried out to ensure that they fit into the estrogen receptors (ERs) and possess anticancer potential. RESULTS: The GC-MS profile of the essential oil revealed the presence of 17 chemicals, with limonene (51.3%), eucalyptol (21.3%), caryophyllene oxide (6.2%), caryophyllene (5.6%), and nerolidol (4.5%) occupying more than one-third of the chromatographic spectrum zone. Guava leaves' essential oil (EO) inhibited DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and exhibited concentration dependent free radical scavenging activity, acting as a potent antioxidant with an IC50 value of 29.3 ± 0.67 µg/mL. The outcome of the MTT assay showed that the extracted guava oil had nearly the same efficacy against breast and liver cancer cells at a low concentration (1 µg/mL), giving 98.3 ± 0.3% and 98.5 ± 0.4% cell viability against HepG2 at 1 µg/mL, respectively. When the concentration of essential oil was increased, it showed a small reduction in the percentage of viable cells. While conducting an in silico study of all the screened compounds, the potential for hydroxycaryophyllene, caryophyllene, caryophyllene oxide, humulene, terpineol, and calamenene to inhibit tumor growth was bolstered due to a resemblance to 4-hydroxytamoxifen, thereby implying that these compounds may act as selective estrogen receptor modulators (SERMs). The ADME analysis of the compounds indicated above revealed that they exhibit excellent drug likeness properties and follow the Lipinski rule of five. CONCLUSIONS: Consequently, they have a substantial anticancer therapeutic potential and can be used for novel drug discovery in the effort to minimize the global burden of breast cancer.

In Vitro Antioxidant and Antimicrobial Potency of Mimosa pudica of Nepalese Terai Region: Insight into L-Mimosine as an Antibacterial Agent.

Aim: The study aimed to evaluate the in vitro antioxidant and antimicrobial potency of Mimosa pudica found wildly in the Terai region of Nepal and assess its physicochemical properties, such as total phenolic content (TPC) and total flavonoid content (TFC). Materials and Methods: The physicochemical properties of ethyl acetate extract of Mimosa pudica (EAMP), such as extractive value, total ash content, loss on drying, and phytochemical screening, were calculated using standard protocols. The TPC was determined by using the Folin-Ciocalteu method taking gallic acid as standard, and TFC was conducted by using the AlCl3 colorimetric method, using a 96-well plate reader. The in vitro antibacterial activity of different concentrations of the extract against four bacterial ATCC strains was determined by the agar well diffusion method in the Mueller Hinton agar (MHA) medium. The in silico molecular docking model was used to ascertain the antibacterial potency of L-mimosine against the selected strains of bacteria used for the in vitro study by calculating the binding affinity towards the protein of bacteria. Results: The preliminary screening of the extract showed the presence of several phytochemicals. The total ash content (7.67%), loss on drying (2.30%), and extractive value (8.966%) were determined by analyzing the crude sample. The total phenolic and flavonoid contents were 418.640 ± 0.018 mg GAE/g (dried extract) and 14.126 ± 0.021 mg QE/g (dried extract), respectively. The extract showed a potent free radical scavenging activity with an IC50 value of 158.95 ± 1.12 µg/mL. The plant extract also demonstrated the antibacterial activity against both Gram-positive bacteria Staphylococcus aureus (15 mm) and Bacillus cereus (22 mm) and Gram-negative bacteria Escherichia coli (17 mm) and Klebsiella pneumoniae (16 mm) at 200 mg/mL concentration of extract. There was a noteworthy binding affinity of antibiotics with almost all selected bacterial proteins with binding energy against Escherichia coli DNA gyrase subunit B (-5.7 kcal/mol), Staphylococcus aureus DNA gyrase subunit B (-6.1 kcal/mol), Bacillus cereus metallothiol transferase (-5.2 kcal/mol), and Klebsiella pneumoniaebeta-lactamase (-6.1 kcal/mole), respectively, with the L-mimosine. Conclusion: The findings of the current study suggest that Mimosa pudica from the Terai region of Nepal is rich in phenolic and flavonoid compounds, has a significant impact on bacterial growth inhibition, and has a notable potential to scavenge free radicals (DPPH). According to the in silico analysis, L-mimosine is a potent antibacterial compound that might be utilised to discover novel antibacterial drugs to combat antibiotic resistance.

Antioxidant, Antibacterial, Antidiabetic Potential, and In silico Analysis of Rhus chinensis from Western Nepal.

BACKGROUND: Rhus chinensis Mill, indigenous wild fruit primarily found in the hilly region of Nepal. The ripe fruit is very sour and considered medicinal as a remedy for colic pain. In addition, their astringent and styptic qualities are used internally to treat illnesses such as diarrhea and hemorrhage. Also, they are used as a common component of polyherbal medications for diabetic mellitus. OBJECTIVES: This work aimed to determine the total phenolic and flavonoid content, antioxidant, antibacterial, α-glucosidase, and α-amylase inhibition activity of the crude extract and fractions of Rhus chinensis Mill. Additionally, molecular docking of compounds from Rhus chinensis was performed. METHODS: Folin Ciocalteu's (FC) reagent was used to estimate total phenolic content. Likewise, the aluminium trichloride method was applied to determine total flavonoid content. A 2,2-diphenyl-1- picrylhydrazyl (DPPH) free radical scavenging assay was performed for the antioxidant activity. Furthermore, the substrate-based enzyme inhibition assay was carried out for α-glucosidase and α- amylase inhibition activity of R. chinensis. P-nitrophenyl-α-D-glucopyranoside (PNPG) and 2- Chloro-4-Nitrophenyl-α-D-Maltotrioside (CNPG3) were used as substrates for α-glucosidase and α- amylase inhibition assay, respectively. Similarly, the well-diffusion method was used for the antibacterial activity. Autodock vina was used to perform molecular docking. RESULTS: The total phenolic and flavonoid content of R. chinensis fruit were 117.092±1.1 mg GAE/g and 62.41±1.23 mg QE/g, respectively. The IC50 value for antioxidant activity of the crude extract and its fractions ranged from 3.12±1.15µg/mL to 50.85±2.10µg/mL. Similarly, the IC50 for α- glucosidase inhibition ranged from2.33±1.01µg/mL to 28.34±2.79µg/mL. Likewise, The IC50 of R. chinensis crude methanolic extract against α-amylase was 120.3±1.382µg/mL. The antibacterial activity of R. chinensis was effective against gram-positive bacteria; Staphylococcus aureus (ZOI=11.0) and Bacillus subtilis (ZOI=9.0). Quercetin-3-O-rhamnoside and Myricetin-3-Orhamnoside showed excellent binding to the active site of protein with binding energy -9.4kcal/mol and -9.6kcal/mol, respectively. CONCLUSION: Rhus chinensis Mill is a potent antioxidant and inhibits enzymes; α-glucosidase and α- amylase. In addition, the methanolic extract of this plant shows antibacterial activity. However, further research is required to determine the inhibiting compounds.

Post-traumatic Pseudoaneurysm of the Internal Carotid Artery with Intractable Epistaxis: A Case Report.

Epistaxis is a common otorhinolaryngology emergency. There are several treatment modalities for epistaxis, but bleeding from the internal carotid artery necessitates a particular treatment technique. We report a case of a 22-years old man who presented to us recurrent episodes of epistaxis and blurry vision in the right eye for one month. The patient had undergone maxillo-facial surgery following a road traffic accident one year back. Bleeding episodes were occasionally severe with blood loss of up to 800 to 1000ml. These episodes were managed conservatively with posterior nasal packing and frequent blood transfusions. A computed tomography-angiography revealed a pseudoaneurysm arising from the cavernous segment of the right internal carotid artery which was managed successfully by embolization of the aneurysm sac with coils. Despite the rarity of internal carotid artery pseudoaneurysm in individuals with a history of trauma, doctors must be aware of the possibility. Timely identification and treatment of a pseudoaneurysm can save a person's life.