Briarenols W–Z: Chlorine-Containing Polyoxygenated Briaranes from Octocoral Briareum stechei (Kükenthal, 1908)

Briareum stechei is proven to be a rich source of 3,8-cyclized cembranoids (briarane) with a bicyclo[8.4.0] carbon core. In the present study, four previously unreported briaranes, briarenols W–Z (1–4), along with solenolide A (5), briarenolide M (6), briaexcavatolide F (7), and brianolide (8), were isolated and characterized through spectroscopic analysis, and the absolute configuration of 8 was corroborated by a single-crystal x-ray diffraction analysis. Briaranes 2 and 5 were found to induce significant inflammatory activity in lipopolysaccharide (LPS)-induced RAW 264.7 mouse macrophage cells by enhancing the expression of the inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins.     

New Diterpenoids from Soft Coral Sarcophyton ehrenbergi

Continuing chemical investigation on the acetone extracts of the soft coral Sarcophyton ehrenbergi collected off the coast of San-hsian-tai, Taitong County, Taiwan led to the isolation of two new diterpenoids, ehrenbergol C and acetyl ehrenberoxide B (1 and 2). The structures of these isolated metabolites were elucidated through extensive spectroscopic analyses. Moreover, in vitro tests show that compounds 1 and 2 displayed antiviral activity towards human cytomegalovirus, with EC₅₀ of 20 and 8.0 µg/mL, respectively.     

Properties of wood plasticization with octanoyl chloride in a solvent-free system

Diffuse reflectance Fourier transform infrared spectroscopy (DRIFT), solid state cross-polarization/magic-angle-spinning ¹³C-nuclei magnetic resonance spectroscopy (CP/MAS ¹³C-NMR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and thermomechanical analysis (TMA) were used in this study to elucidate the characteristics of wood sawdust after esterification. Results revealed that thermoplastic wood was produced by solvent-free esterification using octanoyl chloride. Increasing the duration of treatment enhanced the extent of esterification. After octanoylation, the crystallinity of wood sawdust was decreased, whereas thermoplasticity, hydrophobicity, and thermal stability were enhanced. The complete flow of the octanoylated wood meal was achieved at around 300°C under a force of 0.01 N, indicating that octanoylated wood sawdust is a good thermoplastic material.     

Applying DNA techniques to the identification of the species of dressed toasted eel products

To differentiate the species of processed eel products, the gene identification of four fresh eel species was first established and the species of eel products collected from markets were investigated. Polymerase Chain Reaction (PCR) and sequence analysis were used to determine the genetic variation in a 362-nucleotide region of the mitochondrial cytochrome b gene in four fresh eels including Anguilla japonica, Anguilla anguilla, Anguilla rostrata, and Muraenesox cinereus. It was found that each eel species had a unique genotype, which was no different among fresh, frozen, and sterilized meats. The restriction enzyme HinfI could differentiate the species of A. japonica and A. rostrata but could not differentiate A. anguilla and M. cinereus. Another restriction enzyme, Sau96 I, was valuable in the differentiation of M. cinereus from the other three species of Anguilla. By applying PCR and restriction enzymes, the species of 12 commercial eel products were identified as A. japonica (9 samples), A. anguilla (2), and A. rostrata (1). This indicated that the sequence and restriction enzyme cutting site analyses were very usable to authenticate species of different processed eel products.     

Different central manifestations in response to electroacupuncture at analgesic and nonanalgesic acupoints in rats: a manganese-enhanced functional magnetic resonance imaging study

Acupuncture analgesia is an important issue in veterinary medicine. This study was designed to elucidate central modulation effects in response to electroacupuncture (EA) at different acupoints. Manganese-enhanced functional magnetic resonance imaging was performed in Sprague-Dawley rats after sham acupuncture, sham EA, or true EA at somatic acupoints. The acupoints were divided into 3 groups: group 1, analgesic acupoints commonly used for pain relief, such as Hegu (LI 4); group 2, nonanalgesic acupoints rarely used for analgesic effect, such as Neiguan (PC 6); and group 3, acupoints occasionally used for analgesia, such as Zusanli (ST 36). Image acquisition was performed on a 1.5-T superconductive clinical scanner with a circular polarized extremity coil. The results showed that there was no neural activation caused by EA at a true acupoint with shallow needling and no electric current (sham acupuncture). When EA at a true acupoint was applied with true needling but no electric current (sham EA), there was only a slight increase in brain activity at the hypothalamus; when EA was applied at a true acupoint with true needling and an electric current (true EA), the primary response at the hypothalamus was enhanced. Also, there was a tendency for the early activation of pain-modulation areas to be prominent after EA at analgesic acupoints as compared with nonanalgesic acupoints. In conclusion, understanding the linkage between peripheral acupoint stimulation and central neural pathways provides not only an evidence-based approach for veterinary acupuncture but also a useful guide for clinical applications of acupuncture.     

Sound absorbent,flame retardant warp knitting spacer fabrics: Manufacturing techniques and characterization evaluations

This study proposes a combination for reciprocal reinforcement between warp knitting spacer fabrics and PU foams. PET/Kevlar nonwoven fabrics are made with an 80:20 ratio and an incorporation of various needle-punching speed of 100, 150, 200, 250, and 300 needles/min. Ascribing to having an optimal bursting strength, sound absorption coefficient, and limited oxygen index (LOI), the PET/Kevlar nonwoven fabric that is made by 200 needles/min are selected to be combined with a glass-fiber fabric by applying needle punch in order to form a surface layer. Next, warp knitting spacer fabrics and the nonwoven fabrics are laminated, followed by being combined with polyurethane (PU) foam that are featured with different densities of 200, 210, 220, 230, and 240 kg/m³ in order to form spacer fabric/PU foam composites with multiple functions. The composites are then tested with a drop-weight test, a compression test, a bursting strength test, a sound absorption test, and a horizontal burning test. The test results indicate that all spacer fabric/PU foam composites reach a horizontal burning level of HF1, and their sound absorption coefficients at 2500-4000 Hz also suggest a satisfactory sound absorption. In particular, the optimal residual stress and compressive strength are present when the composites contain 210 kg/m³ PU foam. Similarly, the optimal bursting strength of the composites occurs when they are composed of 230 kg/m³ PU foam. The spacer fabric/PU foam composites are proven to have high strengths, sound absorption, and fire retardant, and thus have promising potentials for use as construction materials and light weight composite planks.     

Fabrication of poly(vinyl alcohol) nanofibers by wire electrode-incorporated electrospinning

Wire electrodes for needleless electrospinning consist of stainless steel wires in place of cylinder electrodes. The effects of different numbers of constituent stainless steel wires on the morphology and diameter of polyvinyl alcohol (PVA) fibers are examined. With 1, 2, 3, or 4 stainless steel wires being twisted as wire electrodes, an 8, 10, or 12 wt.% polyvinyl alcohol (PVA) solution is electrospun into PVA nanofibers by using a needleless electrospinning machine. The morphology and diameter of PVA nanofibers is observed by scanning electron microscopy. The combination of the number of stainless steel wires (two), PVA solution (10 wt.%), and the collecting distance (10 cm) results in the finest diameter and an evenly formed fiber morphology. In addition, the nanofibers exhibit a wide range of diameters when electrospun with an electrode consisting of more than two stainless steel wires. Compared with the cylinder electrode, the use of a wire electrode can form nanofibers, which results in a more even morphology.     

Isolation and characterization of collagens from the skin of giant grouper (Epinephelus lanceolatus)

ABSTRACT

Acid-solubilized collagen (ASC) and pepsin-solubilized collagen (PSC) were extracted from the skin of giant groupers (Epinephelus lanceolatus) with yields of 39.51 and 19.12%, respectively. ASC and PSC consisted of two different α chains (α1 and α2) and were characterized to be type I collagen with no disulfide bond. The imino acid contents of the ASC and PSC from giant grouper skin were 189 and 181 per 1,000 residues, respectively. The maximum endothermic temperatures (T_max) of ASC and PSC measured by differential scanning calorimetry (DSC) were 31.71 and 31.33°C, respectively. The denaturation temperatures of ASC and PSC measured by viscometry were 29.84 and 29.05°C, respectively. The maximum solubility in 0.5 M acetic acid was observed at pH 5 and pH 6 for ASC and PSC, respectively. A sharp decrease in solubility was observed for both ASC and PSC in the presence of NaCl above 3% (w/v).     

Parvalbumin characteristics in the sonic muscle of a freshwater ornamental grunting toadfish (Allenbatrachus grunniens)

The grunting toadfish, Allenbatrachus grunniens, is an ornamental fish in freshwater aquariums, and it has the ability to produce sounds. The sonic muscle of the toadfish is the fastest vertebrate muscle ever measured, and the rates of Ca²⁺ transport and cross-bridge dissociation are also the fastest. Parvalbumins (PAs) are Ca²⁺-binding proteins that help in muscle relaxation in vertebrates. Several PA isoforms have been identified in variable ratios in different muscle types. Both male and female grunting toadfish have intrinsic sonic muscles attached to their swim bladders, but no significant difference in morphology between male and female sonic muscles has been observed. In this study, we used SDS-PAGE and western blotting to characterize the total PA expression and to identify the PAs from the sonic muscle and the white body muscle of A. grunniens. Although the total PA concentrations were similar in sonic and white muscles, there were differences in the isoform percentages. Two and four PA isoforms were identified from sonic muscle and white muscle, respectively. The estimated sizes of PA1, PA2, and PA3 in the sonic muscle of the grunting toadfish were 10, 10.5, and 10.5 kDa, respectively, and the isoelectric points of PA1, PA2, and PA3 in the grunting toadfish were 4.77, 4.58, and 4.42, respectively. In the sonic muscle, the primary PA isoform was PA1, which comprised more than 94 % of total PA, whereas PA2 comprised only 5 % of the total PA content. In contrast, in white muscle, the primary isoform was PA2, which comprised 58 % of the total PA. Both PA1 (with PA1a) and PA3 represented approximately 20 % of the total PA in white muscle. These results indicate that there is no positive correlation between a high PA content and the speed of muscle relaxation; however, PA1 might have the greatest effect on the relaxation of the grunting toadfish’s sonic muscle.