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Breynia cernua has been used as an alternative medicine for wounds, smallpox, cervical cancer, and breast cancer. This plant is a potential source of new plant-derived drugs to cure numerous diseases for its multiple therapeutic functions. An in vitro study revealed that the methanol extract of B. cernua (stem) exhibits antioxidant activity according to DPPH and SOD methods, with IC50 values of 33 and 8.13 ppm, respectively. The extract also exerts antibacterial activity against Staphylococcus aureus with minimum bactericidal concentration of 1875 ppm. Further analysis revealed that the extract with a concentration of 1–2 ppm protects erythrocytes from the ring formation stage of Plasmodium falciparum, while the extract with a concentration of 1600 ppm induced apoptosis in the MCF-7 breast cancer cell line. GC–MS analysis showed 45 bioactive compounds consisting of cyclic, alkyl halide, organosulfur, and organoarsenic compounds. Virtual screening via a blind docking approach was conducted to analyze the binding affinity of each metabolite against various target proteins. The results unveiled that two compounds, namely, N-[β-hydroxy-β-[4-[1-adamantyl-6,8-dichloro]quinolyl]ethyl]piperidine and 1,3-phenylene, bis(3-phenylpropenoate), demonstrated the best binding score toward four tested proteins with a binding affinity varying from −8.3 to −10.8 kcal/mol. Site-specific docking analysis showed that the two compounds showed similar binding energy with native ligands. This finding indicated that the two phenolic compounds could be novel antioxidant, antibacterial, antiplasmodial, and anticancer drugs. A thorough analysis by monitoring drug likeness and pharmacokinetics revealed that almost all the identified compounds can be considered as drugs, and they have good solubility, oral bioavailability, and synthetic accessibility. Altogether, the in vitro and in silico analysis suggested that the extract of B. cernua (stem) contains various compounds that might be correlated with its bioactivities.

Plasmodium falciparum is the most common species of Plasmodium that causes malaria in Southeast Asia. Artemisinin, a drug with the mechanism of action by inducing oxidative stress in infected red blood cells (RBC) is currently used as the main therapy for malaria, after resistance to chloroquine has been found. However, evidence of artemisinin resistance was discovered in several regions in Southeast Asia. Therefore, a research is required to prove the existence of other drugs that have anti-malaria effects. A drug candidate, doxorubicin also can induce the formation of oxidative stress inside the cells. This study aims to determine the activity of doxorubicin to inhibit the development of P. falciparum in vitro. Red blood cell (RBC) infected with P. falciparum were treated with various concentrations of doxorubicin. Giemsa technique was applied to detect P. falciparum inside RBC. After 48 hours of incubation, the culture was observed to measure the number and the confluence of RBC and P. falciparum in the medium. This study revealed that doxorubicin reduced the number of RBC infected with P. falciparum lysis. The effective dose of doxorubicin-inhibit RBC cell lysis is 0.4 μM, which only reduces 81% RBC cell lysis compared to the control group that reduces 95% RBC cell lysis. At this concentration also found a decrease in the number of P. falciparum cells in the medium. The results proved that doxorubicin has an inhibitory effect on the development of P. falciparum and can decrease the lysis of RBC due to P. falciparum infection. This findings provide an insight that doxorubicin is a potential candidate for antimalarial drugs.

Abstractβ-hydroxy amino acids, such as serine, threonine, and phenylserine, are important compounds for medical purposes. To date, there has been only limited exploration of thermostable serine hydroxylmethyltransferase (SHMT) for the synthesis of these amino acids, despite the great potential that thermostable enzymes may offer for commercial use due to their high stability and catalytic efficiencies. ITBSHMT_1 (ITB serine hydroxylmethyltransferase clone number 1) from thermophilic and methanol-tolerant bacteria Pseudoxanthomonas taiwanensis AL17 was successfully cloned. Biocomputational analysis revealed that ITBSHMT_1 contains Pyridoxal-3′-phosphate and tetrahydrofolatebinding residues. Structural comparisons show that ITBSHMT_1 has 5 additional residues VSRQG on loop near PLP-binding site as novel structural feature which distinguish this enzyme with other characterized SHMTs. In silico mutation revealed that the fragment might have very essential role in maintaining of PLP binding on structure of ITBSHMT_1. Recombinant protein was produced in Escherichia coli Rosetta 2(DE3) in soluble form and purified using NiNTA affinity chromatography. The purified protein demonstrated the best activity at 80 °C and pH 7.5 based on the retro aldol cleavage of phenylserine. Activity decreased significantly in the presence of 3 mM transition metal ions but increased in the presence of 30 mM β-mercaptoethanol. ITBSHMT_1 demonstrated Vmax, Km, Kcat, and Kcat/Km at 242 U/mg, 23.26 mM, 186/s, and 8/(mM.s), respectively. The aldol condensation reaction showed the enzyme’s best activity at 80 °C for serine, threonine, or phenylserine, with serine synthesis showing the highest specific activity. Biocomputational analysis revealed that high intramolecular interaction within the 3D structure of ITBSHMT_1 might be correlated with the enzyme’s high thermal stability. The above data suggest that ITBSHMT_1 is a potential and novel enzyme for the production of various β-hydroxy amino acids.

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Sanchez et al. (2005) have shown the structure of vector space genetic code over the Galois field which relate to the physicochemical properties of the genetic code on proteins. From this vector space, an automorphism can be constructed to reflect the mutation process in the genetic code. This study investigates a type of transformation in the LK_ITB5a lipase gene mutation. The result of the study shows that there is a transformation matrix from the wild type gene lipase LK_ITB5a to mutant gene lipase LK_ITB5a H110F which is a diagonal matrix with non-zero determinant. This means that the transformation is an automorphism.