Stenochlaena palustris (Burm.f.) Bedd. (Blechnaceae) or Kelakai is a traditional medicinal plant found in the Indonesian islands of Borneo and Sumatra. It has been used to treat wound healing, infection, and diabetes. This study looked into the free radical scavenging activity, antiplasmodial activity, toxicity, and antibacterial activity against pathogenic bacteria. The species aerial part was extracted with methanol, followed by a liquid-liquid extraction against (n-hexane, dichloromethane, and ethyl acetate). The extracts free radical scavenging activities were determined using DPPH and NO radicals. The antiplasmodial and toxicity assays were conducted using two Plasmodium falciparum strains (3D7 and W2) and the brine shrimp lethality test. In addition, antibacterial activity was determined using the well diffusion method. The results revealed that ethyl acetate depicted potential activities toward the assay. The ethyl acetate showed potential free radical scavenging activities with an IC₅₀ value of 51.63±0.46μg/mL (DPPH) and 60.03±0.65μg/mL (NO). The antiplasmodial activities showed that the ethyl acetate had potential activities among the extracts with an IC₅₀ value of 11.06±0.45μg/mL. However, all the extracts demonstrated nontoxic toward Artemia salina with LC₅₀>1000μg/mL. Furthermore, the ethyl acetate demonstrated intermediate susceptibility against B. cereus ATCC 10876, V. parahaemolyticus ATCC 17802, L. monocytogenes ATCC 7644, and S. Typhimurium ATCC 14028 at a concentration of 500μg/disc. According to these findings, the ethyl acetate extract of S. palustris (Burm.f.) Bedd is a promising source of natural antioxidants and antiplasmodial agents.

Considering the escalating resistance to conventional antifungal medications, it is critical to identify novel compounds that can efficiently counteract this challenge. The purpose of this research was to elucidate the fungicidal properties of secondary metabolites derived from Arcangelisia flava, with a specific focus on their efficacy against Candida species. This study utilized a combination approach comprising laboratory simulations and experiments to discern and evaluate the biologically active constituents present in the dichloromethane extract of A. flava. The in vitro experiments demonstrated that compounds 1 (palmatine) and 2 (fibraurin) exhibited antifungal properties. The compounds exhibited minimum inhibitory concentrations (MICs) ranging from 15.62 to 62.5 µg/mL against Candida sp. Moreover, compound 1 demonstrated a minimum fungicidal concentration (MFC) of 62.5 µg/mL against Candida glabrata and C. krusei. In contrast, compound 2 exhibited an MFC of 125 µg/mL against both Candida species. Based on a molecular docking study, it was shown that compounds 1 and 2 have a binding free energy of −6.6377 and −6.7075 kcal/mol, respectively, which indicates a strong affinity and specificity for fungal enzymatic targets. This study utilized pharmacophore modeling and Density Functional Theory (DFT) simulations to better understand the interaction dynamics and structural properties crucial for antifungal activity. The findings underscore the potential of secondary metabolites derived from A. flava to act as a foundation for creating novel and highly efficient antifungal treatments, specifically targeting fungal diseases resistant to existing treatment methods. Thus, the results regarding these compounds can provide references for the next stage in antifungal drug design. Further investigation is necessary to thoroughly evaluate these natural substances’ clinical feasibility and safety characteristics, which show great potential as antifungal agents.

Chalcone analogs have been reported to have a variety of exciting biological activities, such as anticancer, anti-inflammatory, antioxidant, photoprotective, antibacterial, and antidiabetic activities. Therefore, analogs of these compounds have been widely synthesized as intermediate compounds or target molecules in the discovery of bioactive compounds to be applied in the pharmaceutical field. The purpose of this study is to synthesize chalcone analog compounds (E)-1-(4-hydroxyphenyl)-3-(4-methoxyphenyl) prop-2-en-1-on with the microwave irradiation method and explore some of the biological activities of these compounds, including testing the antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) method, in vitro sunscreen activity by microplate method, and antibacterial activity by disk diffusion method. DPPH test results indicate that the compound has weak antioxidant activity, with an IC50 value of 300.43 µg/mL. However, the compound showed excellent potential as a UV B and UV A filter at a concentration of 150 µg/mL with a value of %Te of 0.73±0.10% (sunblock), %Tp of 0.07±0.00% (sunblock), SPF value of 21.10±1.46 (ultra-protection) and potentially better than benzophenone-3 as a standard sunscreen. Then, disk diffusion testing showed that the compound had weak antibacterial activity against Staphylococcus aureus and did not show antibacterial activity against Escherichia coli bacteria at test concentrations of 30, 60, and 120 µg/disk.

In recent years, liquid smoke rice husk (LSRH) has shown its therapeutic potency to diabetes, wound healing, stomatitis, and periodontitis. The phenol, 6-octadecenoic acid, oleic acid, and 9-octadecanoic acid were responsible for their therapeutic effect. The LSRH also demonstrated their potential for infectious diseases such as coronavirus disease (COVID-19). Therefore, the molecular dynamics (MDs) simulation and pharmacophore analysis was performed to analyse the binding stability of 6-octadecenoic and oleic acid. Based on MD simulation, 6-octadecenoic and oleic acids seemed to retain their interactions with Ser144 and Thr24, respectively, with hydrogen bond distance less than 2.9 Å. This interaction was stable during the simulation and has hydrophobic and hydrogen bonds/acceptors. The 6-octadecenoic acid and oleic acid were confirmed to have great potency as inhibitors for COVID-19. These compounds also showed that the existence of hydrophobic and hydrogen bonds/acceptors could increase biological activity.

This research has been successfully synthesized three compounds of 1,3,5-triaryl pyrazole derivatives by two steps reaction. Firstly, pyrazoline (4a-c) compound was obtained by one-pot reaction of aromatic ketones, aldehyde and hydrazine in basic condition. Then, pyrazole (5a-c) compound was obtained by oxidative aromatization of compound 4 in the presense of acetic acid. Chemical structure of predicted molecules was confirmed by FTIR, NMR and HRMS spectroscopy data analysis. Antiproliferative activity of compound 5a-c were evaluated by in vitro assay against MCF-7 cells line and molecular docking simulation against ERα (PDB ID: 3ERT) using MOE 2019. Biological evaluation result showed that pyrazole compounds had weak antiproliferative activity against MCF-7 cells with IC50 were > 1000 µM, whereas the docking studies agrees the result.