An antioxidant protein in Curcuma comosa Roxb. Rhizomes

Curcuma comosa Roxb. is an indigenous Thai herb which is usually used as a food ingredient but it is also used in traditional folk medicine for the treatment of uterine inflammation. The crude protein extract from the rhizomes of this plant was found to possess free radical scavenging capacity, as detected by the DPPH assay. This antioxidant activity was purified by DEAE anion exchange chromatography to a fraction (called IE-1) that was comprised of a single main protein band of ∼18 kDa (UB-DEAE), as determined by SDS–PAGE resolution with Coomassie blue staining, and had a specific activity of 193.8 U/mg. In-gel trypsin digestion of the SDS–PAGE resolved UB-DEAE band followed by liquid chromatography–tandem mass spectrometry produced three reliably sequenced peptides, which all were found to very likely be fragments of a superoxide dismutase homologue (SOD, EC 1.15.1.1), an antioxidant enzyme that has been found in several plants. In support of this notion, the IE-1 fraction was found to yield positive results with the riboflavin–nitroblue tetrazolium (NBT) assay, a standard test for SOD-like activity. Together, these data then support the existence of an SOD homologue antioxidant protein in the rhizomes of C. comosa as a contributing agent to the total observed antioxidant activity.     

Removal of heavy metals from aqueous systems with thiol functionalized superparamagnetic nanoparticles

We have shown that superparamagnetic iron oxide (Fe3O4) nanoparticles with a surface functionalization of dimercaptosuccinic acid (DMSA) are an effective sorbent material for toxic soft metals such as Hg, Ag, Pb, Cd, and Tl, which effectively bind to the DMSA ligands and for As, which binds to the iron oxide lattices. The nanoparticles are highly dispersible and stable in solutions, have a large surface area (114 m2/g), and have a high functional group content (1.8 mmol thiols/g). They are attracted to a magnetic field and can be separated from solution within a minute with a 1.2 T magnet. The chemical affinity, capacity, kinetics, and stability of the magnetic nanoparticles were compared to those of conventional resin based sorbents (GT-73), activated carbon, and nanoporous silica (SAMMS) of similar surface chemistries in river water, groundwater, seawater, and human blood and plasma. DMSA-Fe3O4 had a capacity of 227 mg of Hg/g, a 30-fold larger value than GT-73. The nanoparticles removed 99 wt% of 1 mg/L Pb within a minute, while it took over 10 and 120 min for Chelex-100 and GT-73 to remove 96% of Pb.     

Sodium Cardanol Sulfonate Surfactant from Cashew Nut Shell Liquid

Sodium cardanol sulfonate surfactant was synthesized from cardanol from cashew nut shell liquid. Surfactant properties of cardanol sulfonate were determined and compared with dodecylbenzene sulfonate. Surface tension values were determined to be 32.25 mN/m for cardanol sulfonate at 20% w/v and 28.00 mN/m for dodecylbenzene sulfonate at 15% w/v. Critical micelle concentrations of dodecylbenzene sulfonate and cardanol sulfonate were found to be 0.435 and 0.372 mol/L, respectively. In comparison with dodecylbenzene sulfonate, the relative detergency of cardanol sulfonate was calculated to be 93.7% compared to dodecylbenzene sulfonate. Results suggest that cardanol sulfonate can be used as alternative anionic surfactant.

Anti-osteoclastogenic,estrogenic, and antioxidant activities of cell suspension cultures and tuber root extracts from Pueraria mirifica

The flavonoid contents of intact tubers and cell culture media were determined and physiological activities of Pueraria mirifica extracts were investigated. The total flavonoid contents from cell culture media (PMC) were higher than from tubers (PMT). Results from in vivo estrogenic activity assays indicated that PMT had a strong estrogenic activity in ovariectomized rats. The same amount of PMC exhibited a weak activity. In vitro osteoclast suppression investigations indicated that both PMT and PMC extracts exhibited anti-osteoclastogenic activities with low toxicities in a standard test cell line. Determination of the antioxidant potential using the DPPH assay revealed that the IC₅₀ value for PMT was lower than for PMC. P. mirifica cell cultures produce more flavonoids and exhibit a mild estrogenic and more antioxidant activities than tubers.     

Cationic Polymer Modified Mesoporous Silica Nanoparticles for Targeted siRNA Delivery to HER2+ Breast Cancer

In vivo delivery of siRNAs designed to inhibit genes important in cancer and other diseases continues to be an important biomedical goal. A new nanoparticle construct that is engineered for efficient delivery of siRNA to tumors is now described. The construct comprises a 47‐nm mesoporous silica nanoparticle core coated with a crosslinked polyethyleneimine–polyethyleneglycol copolymer, carrying siRNA against the human epidermal growth factor receptor type 2 (HER2) oncogene, and coupled to the anti‐HER2 monoclonal antibody (trastuzumab). The construct is engineered to increase siRNA blood half‐life, enhance tumor‐specific cellular uptake, and maximize siRNA knockdown efficacy. The optimized anti‐HER2 nanoparticles produce apoptotic death in HER2 positive (HER2⁺) breast cancer cells grown in vitro, but not in HER2 negative (HER2^?) cells. One dose of the siHER2–nanoparticles reduces HER2 protein levels by 60% in trastuzumab‐resistant HCC1954 xenografts. Administration of multiple intravenous doses over 3 weeks significantly inhibits tumor growth (p < 0.004). The siHER2‐nanoparticles have an excellent safety profile in terms of blood compatibility and low cytokine induction, when exposed to human peripheral blood mononuclear cells. The construct can be produced with high batch‐to‐batch reproducibility and the production methods are suitable for large‐scale production. These results suggest that this siHER2‐nanoparticle is ready for clinical evaluation.     

Effects of protein hydrolysate from chicken feather meal on tyrosinase activity and melanin formation in B16F10 murine melanoma cells

Tyrosinase is a copper-containing enzyme that controls mammalian melanogenesis. Tyrosinase inhibitors are important for their potential application in cosmetic products. Chicken feather meal is a rich source of amino acids, which have been linked with tyrosinase inhibition activity. This study investigated the tyrosinase inhibitory properties of protein hydrolysates prepared from chicken feather meal. Protein hydrolysates prepared by pepsin-pancreatin with MW <3 kDa exhibited strong tyrosinase inhibition activity for both monophenolase (IC₅₀ 5.780 ± 0.188 µg/mL) and diphenolase activities (IC₅₀ 0.040 ± 0.024 µg/mL) in a cell-free mushroom tyrosinase system. These samples were uncompetitive inhibitors with Ki values of 18.149 and 27.189 µg/mL in monophenolase and diphenolase activities, respectively. A cell culture model showed that this hydrolysate had the strongest inhibition on the viability of B16F10 cells (IC₅₀ 1.124 ± 0.288 µg/mL) and 0.210 µg/mL of the sample exhibited inhibition of tyrosinase activity by 50.493% and melanin synthesis by 14.680% compared to the control.     

Hemagglutinating activity and corresponding putative sequence identity from Curcuma aromatica rhizome

BACKGROUND: Curcuma aromatica is a medicinal plant belonging to the Zingiberaceae family with an incomplete genome sequence. It has been reported that extract from the rhizome of this plant contains haemagglutinating activity. In this study the profile of fractions containing hemagglutinating activity is described. RESULTS: Following extraction with saline buffer, the protein solution was fractionated by ammonium sulfate precipitation. Ion‐exchange chromatography was completed on fast‐flow SP‐Sepharose, as well as gel filtration chromatography on Superdex 75. The active fractions were then separated by one‐dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis and labeled proteins were digested with trypsin. The digest bands were analyzed by reversed‐phase liquid chromatography—tandem mass spectrometry. Inferred peptide sequences were used in Mascot searching and mass spectrometry‐driven BLAST (MS‐BLAST) homology searches allowed the recognition of related proteins in other species of Viridiplantae. Six putative proteins from nine bands showed similarity with lectin sequences. CONCLUSION: This study reports the identification of six lectins from the Curcuma aromatica rhizome achieved by mass spectrometry using MS‐BLAST algorithms to search for homology between de novo determined peptide sequences and protein sequences available in sequence databases. Copyright © 2008 Society of Chemical Industry     

Antifungal and antibacterial activities of lectin from the seeds of Archidendron jiringa Nielsen

A Archidendron jiringa Nielsen lectin was purified by aqueous extraction, 90% ammonium sulphate precipitation and concanavalinA-Sepharose 4B affinity chromatography. Its specific activity was of 88.3 × 10² hemagglutination unit/mg protein for a yield of 51.6% total protein. The molecular weight is of 35.7 kDa. It has hemagglutinating activity against human blood group, rabbit, mouse, rat, guinea pig, geese and sheep erythrocytes. The hemagglutination activity of lectin was relatively insensitive to acidic pH above 2, had an optimal activity at pH 8, and stable below 45 °C for 30 min. The activity was stimulated by Ca²⁺, Mg²⁺ and Mn²⁺. The internal sequence indicated similarity with legume lectin family. Moreover, even at low concentrations antifungal activity was observed against Exserohilum turcicum, Fusarium oxysporum and Colletotrichum cassiicola. The minimal inhibitory concentrations were 0.227, 0.0567 and 0.0567 mg/ml for Bacillus subtilis, Staphylococcus aureus, and Candida albicans, respectively.     

Brominated phenol–formaldehyde resin as an adhesive for plywood

A brominated phenol–formaldehyde resin was investigated as a plywood adhesive to study the effect of bromine on the physical and flammability properties of this resin. The results of these studies showed that brominated phenol–formaldehyde resin of 10% bromine content by weight of the phenol–formaldehyde resin was suitable to be used as a plywood adhesive. The optimal compressing temperature and compressing time were 110°C and 30 min, respectively. The prepared plywood obtained from the optimal condition gave a high shear strength, good flame retardancy, and good resistance to both hot and cold water. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1918–1924, 2003