The protein from the seeds of melinjo ( Gnetum gnemon ) was purified using a precipitation method and ion exchange chromatographic techniques to identify the potent antioxidant and free radical scavenging activities. Two antioxidant protein fractions were isolated from G. gnemon seed with molecular weights of approximately 30 kDa (Gg-AOPI) and 12 kDa (Gg-AOPII) by SDS-PAGE. The N-terminal amino acid sequence of Gg-AOPII is Gly-Asn-Gly-Lys-Ala-Thr-Val-Ala-Ile-Leu-Val-Lys-Glu-Lys-Val-Glu-Tyr-Gly-Glu-Glu, and the result of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) analysis showed that they were distinct from each other; no protein in database matching was found to both Gg-AOPI and Gg-AOPII. The antioxidant or free radical scavenging activities of Gg-AOPs were investigated by employing in vitro assay systems including the inhibition of linoleic acid autoxidation, scavenging effect on α,α-diphenyl-β-picrylhydrazyl free radical (DPPH), 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), reducing power, chelating abilities of metal ions Cu(2+) and Fe(2+), and protections against hydroxyl radical-mediated DNA damages. The result showed that two protein fractions exhibited significant (p < 0.05) antioxidant activities against free radicals such as DPPH, ABTS, and superoxide anion and showed activities similar to those of glutathione (G-SH) and BHT in a linoleic acid emulsion assay system. Moreover, Gg-AOPI and Gg-AOPII also exhibited notable reducing power and strong chelating effect on Fe(2+) and protected hydroxyl radical induced oxidative DNA damage. The data obtained by the in vitro systems obviously established the antioxidant potency of Gg-AOPs.

In plants, transgenes with inverted repeats are used to induce efficient RNA silencing, which is also frequently induced by highly transcribed sense transgenes. RNA silencing induced by sense transgenes is dependent on RNA-dependent RNA polymerase 6 (RDR6), which converts single-stranded (ss) RNA into double-stranded (ds) RNA. By contrast, it has been proposed that RNA silencing induced by self-complementary hairpin RNA (hpRNA) does not require RDR6, because the hpRNA can directly fold back on itself to form dsRNA. However, it is unclear whether RDR6 plays a role in hpRNA-induced RNA silencing by amplifying dsRNA to spread RNA silencing within the plant. To address the efficiency of hpRNA-induced RNA silencing in the presence or absence of RDR6, Wild type (WT, Col-0) and rdr6-11 Arabidopsis thaliana lines expressing green fluorescent protein (GFP) were generated and transformed with a GFP-RNA interference (RNAi) construct. Whereas most GFP-RNAi-transformed WT lines exhibited almost complete silencing of GFP expression in the T1 generation, various levels of GFP expression remained among the GFP-RNAi-transformed rdr6-11 lines. Homozygous expression of GFP-RNAi in the T3 generation was not sufficient to induce complete GFP silencing in several rdr6-11 lines. Our results indicate that RDR6 is required for efficient hpRNA-induced RNA silencing in plants. INTRODUCTIONGene silencing is a mechanism that employs small RNAs and protein effectors to interfere with the expression of homologous genes at the transcriptional and post-transcriptional levels (Voinnet, 2008). Transcriptional gene silencing (TGS), which takes place through repression of transcription, is often associated with methylation of the corresponding homologous promoter (Neuhuber et al., 1994;Park et al., 1996). Post-transcriptional gene silencing (PTGS), occurring through sequencespecific degradation of target mRNAs, is characterized by accumulation of small interfering RNA (siRNA) and methylation of target gene sequences (Depicker and Montagu, 1997;Vaucheret et al., 2001). Gene silencing was first discovered in plants and is highly conserved among multicellular eukaryotes. It initiates with the formation of dsRNA, which is subsequently processed into siRNA. siRNAs are produced from dsRNAs by an RNase III-like enzyme called DICER, which has dsRNA-binding, RNA helicase and P-element-induced wimpy testes (PIWI)-Argonaute (AGO)-Zwille (PAZ) domains (Bernstein et al., 2001). Plants possess four DICER homologs: DCL1, DCL2, DCL3, and DCL4. DCL1 is responsible for producing various sizes of microRNAs (small RNAs encoded in the genome), whereas DCL2, DCL3, and DCL4 produce 22, 24, and 21 nucleotide (nt) siRNAs, respectively (Bartel, 2004;Dunoyer et al., 2005;Xie et al., 2004). The 24 nt siRNAs are reported to guide RNAdirected DNA methylation (RdDM) in plants (Wassenegger et al., 1994), whereas the 21 and 22 nt siRNAs are known to trigger cognate mRNA degradation and secondary siRNA biogenesis, respectively (Chen et al., 2010;Hamilton et al., 2002).The guide str...

Preparation and characterization of a novel cocrystal of atorvastatin calcium with succinic acid coformer were successfully performed. This research aims to modify the crystalline form of atorvastatin calcium through cocrystallization with succinic acid coformer. The cocrystal was prepared by a solvent evaporation method and characterized by Powder X-Ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM). The atorvastatin calcium-succinic acid cocrystal has new crystalline peaks at 2θ of 12.9, 18.2 and 26.7° indicating the formation of a new crystalline phase. The cocrystal showed the melting point at 205.7 °C with an enthalpy of fusion 30.2 J/g which is different from the initial components. The FTIR spectra of cocrystal showed the shifting of absorption peaks of groups of initial components indicating of formation of atorvastatin calcium-succinic acid cocrystal through acid–amide intermolecular hydrogen bond interactions. The solubility and dissolution test showed that the cocrystal has solubility and dissolution rate significantly higher than the solubility and dissolution rate of pure atorvastatin calcium.

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roteins hydrolyzed from melinjo seeds (Gnetum gnemon) at green (GM), yellow (YM) and red (RM) stages of maturity were studied for their effectiveness in antioxidant and antidiabetic activities. The seed protein extract was hydrolyzed using alcalase 2.4L, and the resulting hydrolysates with the highest degree of hydrolysis, protein profile, and the most potent contributors to antioxidant and invitro antidiabetic activities were identified. The degree of hydrolysis value of hydrolysates ranged from 52-84%, and the SDS-PAGE protein profile showed two distinct bands in which the band with molecular weight of 30 kDa degraded more intensively. Antioxidant capacity was measured using different standard methods, including radical cation 2,2-azinobis-(3-ethylbenzothizoline-6-sulphonate) (ABTS•+) assay, hydroxyl radical (OH•), and superoxide anion (O2•-) scavenging. The green hydrolysate (GMH) had significantly higher (p<0.05) free radical scavenging (ABTS•+, OH•, and O2•-) activities than that of the yellow hydrolysate (YMH) and red hydrolysate (RMH). However, invitro antidiabetic testing was performed based on the inhibitory activity of α-amylase and α-glucosidase. GMH was found to be more effective than YMH and RMH. These results showed that the antioxidant and antidiabetic activity in hydrolyzed GM protein has high potential to be utilized as natural nutraceuticals.