Linoleic acid‐rich guava seed oil: Safety and bioactivity

Guava (Psidium guajava) is a widely consumed fruit and has been commercialized in markets. The seeds are by‐products of the processing procedures performed by the commercial guava juice industry. They are considered a nutritional resource that has been poorly utilized as they contain essential fatty acids such as linoleic acid (LA) and phenolics in abundance. In the study, guava seed oil (GSO) was used, which was obtained by hexane extraction of guava seeds to determine composition and test toxicity, cell migration, cancer cell viability, and plasmodium growth. GSO was found to be relatively nontoxic to normal hepatocytes and peripheral blood mononuclear cells, with mice for 14 days showing median lethal dose (LD₅₀) > 10 mg/kg and rats for up to 90 days. Surprisingly, the oil inhibited the proliferation of the human erythroleukemic cells in a dose‐dependent manner with the half maximal inhibitory concentration values of 155 and 137 μg/ml at 24 and 48 hr, respectively. Importantly, GSO at 500 μg/ml was found to increase the degree of migration of keratinocytes (HaCaT). These observations suggest that edible P. guajava seed oil, which is abundant with linoleic acid and antioxidants, can promote skin wound healing and inhibit the proliferation of leukemic cells.     

In vivo assessment of oral administration of probucol nanoparticles in rats

Pharmacokinetic profiles of probucol were evaluated after oral administration of the various nanosuspensions in rats. Probucol nanoparticles were prepared by co-grinding with various molecular weights of polyvinylpyrrolidone (PVP K12, PVP K17 and PVP K30) and sodium dodecyl sulfate (SDS). The average particle sizes of probucol after dispersing the ternary ground mixtures (GMs), probucol/PVP K12/SDS, probucol/PVP K17/SDS and probucol/PVP K30/SDS into water were 28, 75 and 89 nm respectively. The ternary GM suspensions with PVP K17/SDS and PVP K30/SDS were stable at 25 degrees C. However the particle size of probucol from the ternary GM with PVP K12/SDS gradually increased. Pharmacokinetic profiles of probucol indicated that variation in particle surface condition covered with PVP and SDS in addition to the particle size affected the improvement of in vivo absorption of probucol. The ternary GM with PVP K12/SDS exhibited a superior improvement of probucol absorption compared to the GMs with PVP K17/SDS and PVP K30/SDS. The binary GM with PVP or SDS and physical mixtures with PVP and/or SDS did not show significant differences in the area under the plasma concentration-time curve compared to the unprocessed probucol. In conclusion, preparation of probucol nanoparticles by co-grinding with PVP K12 and SDS could be a promising method for bioavailability enhancement.     

Comparison of chemical profiles,antioxidation, inhibition of skin extracellular matrix degradation,and anti-tyrosinase activity between mycelium and fruiting body of Cordyceps militaris and Isaria tenuipes

ContextCordyceps militaris and Isaria tenuipes (Cordycipitaceae) are high-value fungi that are used for health-promoting food supplements. Since laboratory cultivation has begun for these fungi, increased output has been achieved.ObjectiveThis study compared the chemical profiles, antioxidant, anti-tyrosinase, and skin extracellular matrix degradation inhibition between mycelium and fruiting body of C. militaris and I. tenuipes.Materials and methodsThe antioxidative potential of 10% v/v aqueous infused extract from each fungus was separately investigated using 2,2-azinobis(3-ethylbenzo-thiazoline-6-sulphonic acid) (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric reducing antioxidant ability, and ferric thiocyanate methods. The inhibition against MMP-1, elastase, and hyaluronidase were determined to reveal their anti-wrinkle potential. Anti-tyrosinase activities were determined.ResultsC. militaris and I. tenuipes extracts were found to contain a wide range of bioactive compounds, including phenolics, flavonoids, and adenosine. A correlation was discovered between the chemical compositions and their biological activities. The extract from I. tenuipes fruiting body (IF) was highlighted as an extraordinary elastase inhibitor (IC₅₀ = 0.006 ± 0.004 mg/mL), hyaluronidase inhibitor (IC₅₀: 30.3 ± 3.2 mg/mL), and antioxidant via radical scavenging (ABTS IC₅₀: 0.22 ± 0.02 mg/mL; DPPH IC₅₀: 0.05 ± 0.02 mg/mL), thereby reducing ability (EC₁: 95.3 ± 4.8 mM FeSO₄/g extract) and lipid peroxidation prevention (IC₅₀: 0.40 ± 0.11 mg/mL). IF had a three-times higher EC₁ value than ascorbic acid and significantly higher elastase inhibition than epigallocatechin gallate.Discussion and conclusionsIF is proposed as a powerful natural extract with antioxidant and anti-wrinkle properties; therefore, it is suggested for further use in pharmaceutical, cosmeceutical, and nutraceutical industries.     

Molecular Interaction among Probucol/PVP/SDS Multicomponent System Investigated by Solid-State NMR

Purpose Effects of polyvinylpyrrolidone (PVP) molecular weight on the solid-state intermolecular interactions among probucol/PVP/sodium dodecyl sulfate (SDS) ternary ground mixtures (GM) and the formation of nanoparticles were investigated by solid-state NMR spectroscopy.Materials and Methods Ternary GMs of probucol were prepared with PVP (K12, K17, K30 or K90) and SDS at a weight ratio of 1:3:1 and were ground for 15, 30 and 60 min. Solid-state interactions were evaluated using powder X-ray diffraction (PXRD) and solid-state cross polarization/magic angle spinning (CP/MAS) ¹³C NMR spectroscopy. A high resolution scanning electron microscopy (SEM) was employed to observe nanoparticles of probucol in the GM.Results The solid-state ¹³C CP/MAS NMR results indicate that the low molecular weight PVP interacts with probucol and SDS more strongly than the high molecular weight PVP in the ternary GM. This finding was consistent with the result that smaller drug nanoparticles were obtained using low molecular weight of PVP. SEM images of probucol/PVP K12/SDS confirmed the presence of nanoparticles (15–25 nm) in the GM.Conclusions Grinding-induced solid-state interactions among drug, PVP and SDS could be detected using solid state ¹³C NMR. The interactions in both probucol-PVP and PVP-SDS should occur simultaneously to generate nanometer-sized particles of probucol.     

Houttuynia cordata Thunb fraction induces human leukemic Molt-4 cell apoptosis through the endoplasmic reticulum stress pathway

Houttuynia cordata Thunb (HCT) is a native herb found in Southeast Asia which features various pharmacological activities against allergy, inflammation, viral and bacterial infection, and cancer. The aims of this study were to determine the cytotoxic effect of 6 fractions obtained from silica gel column chromatography of alcoholic HCT extract on human leukemic Molt-4 cells and demonstrate mechanisms of cell death. Six HCT fractions were cytotoxic to human lymphoblastic leukemic Molt-4 cells in a dose-dependent manner by MTT assay, fraction 4 exerting the greatest effects. Treatment with IC50 of HCT fraction 4 significantly induced Molt-4 apoptosis detected by annexinV-FITC/propidium iodide for externalization of phosphatidylserine to the outer layer of cell membrane. The mitochondrial transmembrane potential was reduced in HCT fraction 4-treated Molt-4 cells. Moreover, decreased expression of Bcl-xl and increased levels of Smac/Diablo, Bax and GRP78 proteins were noted on immunoblotting. In conclusion, HCT fraction 4 induces Molt-4 apoptosis cell through an endoplasmic reticulum stress pathway.     

Formation mechanism of colloidal nanoparticles obtained from probucol/PVP/SDS ternary ground mixture

The purpose of this study was to investigate the formation mechanism of colloidal nanoparticles after dispersion of probucol/polyvinylpyrrolidone (PVP)/sodium dodecyl sulphate (SDS) ternary ground mixture (GM) into water. Probucol, PVP and SDS were mixed at a weight ratio of 1:3:1 and ground for 30 min with a vibrational rod mill. The morphology and physicochemical properties were investigated through high resolution scanning electron microscopy (SEM), environmental SEM, dynamic light scattering, (13)C NMR and zeta potential measurements. SEM images confirmed the presence of 20 nm size primary particles in the GM powder of probucol/PVP K17/SDS. Spherical nanoparticles with a size of around 100 nm, formed after dispersion of the GM into water, suggested an agglomeration of the primary particles. A further agglomeration of around 160 nm was observed with the stability experiment. Zeta potential and particle size measurements using latex beads revealed that PVPK 17/SDS complex was adsorbed on the probucol particle surface forming a layered structure. A similar agglomeration behavior was observed using the GM of probucol/PVP K12/SDS, though the molecular state of the PVPK 12/SDS complex at the particle surface was different from that of the PVPK 17/SDS complex. (13)C NMR results suggested that intermolecular interactions between PVP K12 and SDS did not reach the same level as the interactions between PVP K17 and SDS. This study proposed a formation mechanism of colloidal nanoparticles.