Ethyl Formate Fumigation for Control of the Scale Insect Asiacornococcus kaki, a Quarantine Pest on Sweet Persimmon, Diospyros kaki: Efficacy, Phytotoxicity and Safety.

Sweet persimmons are a valuable export commodity. However, the presence of live insects such as Asiacornococcus kaki limits their access to many export markets. Methyl bromide, traditionally used for pest control, is damaging to human health and the environment. Ethyl formate (EF) is a viable alternative; however, its effectiveness against A. kaki on sweet persimmon fruit is unknown. We evaluated the effectiveness of EF fumigation in controlling A. kaki present under the calyx of persimmon fruit. The hatching rate of eggs and the survival rates of nymphs and adults of A. kaki at low temperatures, its LCt50 and LCt99 after EF exposure, and phytotoxic damage caused by EF were evaluated in laboratory-scale and commercial-scale tests. The dose-response tests showed that the EF LCt99 at 5 °C was 9.69, 42.13, and 126.13 g h m-3 for adults, nymphs, and eggs, respectively. Commercial-scale tests demonstrated EF efficacy against all A. kaki stages without causing phytotoxic effects on persimmons, though the eggs of A. kaki were not completely controlled in linear low-density polyethylene (LLDPE)-packaged fruit. This study demonstrated that EF is a potential fumigant for quarantine pretreatment, especially before persimmon fruit is packed with LLDPE film, to control A. kaki infesting sweet persimmon fruit.

Evaluation of Enzymatically Modified Soy Protein Isolate Film Forming Solution and Film at Different Manufacturing Conditions.

The effects of transglutaminase on soy protein isolate (SPI) film forming solution and films were investigated by rheological behavior and physicochemical properties based on different manufacturing conditions (enzyme treatments, enzyme incubation times, and protein denaturation temperatures). Enzymatic crosslinking reaction and changes in molecular weight distribution were confirmed by viscosity measurement and SDS-PAGE, respectively, compared to 2 controls: the nonenzyme treated and the deactivated enzyme treated. Films treated with both the enzyme and the deactivated enzyme showed significant increase in tensile strength (TS), percent elongation (%E), and initial contact angle of films compared to the nonenzyme control film due to the bulk stabilizers in the commercial enzyme. Water absorption property, protein solubility, Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectroscopy revealed that enzyme treated SPI film matrix in the molecular structure level, resulted in the changes in physicochemical properties. Based on our observation, the enzymatic treatment at appropriate conditions is a practical and feasible way to control the physical properties of protein based biopolymeric film for many different scientific and industrial areas. PRACTICAL APPLICATION: Enzymes can make bridges selectively among different amino acids in the structure of protein matrix. Therefore, protein network is changed after enzyme treatment. The behavior of biopolymeric materials is dependent on the network structure to be suitable in different applications such as bioplastics applied in food and pharmaceutical products. In the current research, transglutaminase, as an enzyme, applied in soy protein matrix in different types of forms, activated and deactivated, and different preparation conditions to investigate its effects on different properties of the new bioplastic film.

Stability of ß-Lapachone upon Exposure to Various Stress Conditions: Resultant Efficacy and Cytotoxicity.

Even though ß-lapachone is a promising compound with antitumor, antiinflammatory, antineoplastic, and wound-healing effects, there are still issues concerning its chemical stability and degradation mechanisms. The objective of this study was to obtain degradation profiles of ß-lapachone and evaluate its chemical stability under various stress conditions. Moreover, the correlation between stability and efficacy was evaluated. The degradation study of ß-lapachone was performed using heat, acid, base, oxidation, and light conditions. Kinetics and degradation profiles were investigated with HPLC and LC-MS. The stability indicated in the LC method was validated according to the International Conference on Harmonization guidelines. Human dermal fibroblast (HDF) cells were cultured with the standard and its degraded samples in the cellular activity and cytotoxicity test. ß-Lapachone was relatively unstable upon exposure to light, and its photodegradation was accelerated with high relative humidity. Three degradants were identified, and their degradation followed zero-order kinetics. It was shown to degrade to phthalic acid under oxidative conditions, and the degradation kinetics were dependent on the concentration of hydrogen peroxide. Two degradation products were identified upon exposure to basic conditions, which followed first-order kinetics. ß-Lapachone was relatively stable under acidic and thermal conditions. It increased the synthesis of collagen compared with the control. However, as the contents decreased, the synthesis of collagen also decreased in the photodegraded samples. ß-Lapachone did not exert cytotoxic effects at the effective concentration in the cytotoxicity test. Therefore, in order to ensure efficacy and safety, the chemical stability of ß-lapachone needs to be controlled carefully while considering instability mechanisms.

Enhancement of Curcumin Solubility by Phase Change from Crystalline to Amorphous in Cur-TPGS Nanosuspension.

Nanosuspensions (NSs) were fabricated to enhance water solubility, dissolution rate, and oral adsorption of water insoluble curcumin using sonoprecipitation method. As a good stabilizer, d-α-Tocopherol polyethylene glycol 1000 succinate (TPGS) was used to improve the stability of curcumin-TPGS NSs (Cur-TPGS NSs). Ultrasonic homogenization (UH) could effectively enhance the solubility of curcumin and to produce homogeneous NSs with small particle sizes. Water solubility of curcumin was significantly improved from 0.6 µg/mL in pure water to 260 µg/mL in the mixture of curcumin and TPGS (1:10) with UH treatment. The mean particle size of Cur-TPGS NSs was decreased significantly after UH and maintained between 208 and 246 nm. Lyophilized powder of Cur-TPGS NSs was dissolved about 91.08% whereas the pristine curcumin powder was dissolved only 6.5% at pH 7.4. This study showed a great potential of Cur-TPGS NSs as a good nano-formulation of curcumin with enhanced solubility and improved oral adsorption.

Chemical stability and in vitro and clinical efficacy of a novel hybrid retinoid derivative, bis-retinamido methylpentane.

The anti-aging agent, retinol, has fewer side effects and similar biological activity compared to retinoic acid. However, retinol becomes unstable when exposed to light and heat. A novel hybrid retinoid derivative, bis-retinamido methylpentane (RS-2A), was newly developed to overcome the limitations. This study evaluated the chemical stability of RS-2A under thermal and light conditions by examining degradation profiles, and assessed the in vitro biological activity, cytotoxicity, and clinical efficacy. Chemical stability and degradation profiles were investigated with HPLC and LC-MS. Especially, photo-stability of RS-2A was analyzed under various conditions, such as change of physical state and concentration, different solvents, and various excipients. For analyses of cellular activity and cytotoxicity, human dermal fibroblasts were cultured with RS-2A. To evaluate the safety and efficacy of the compound with the cellular results, RS-2A was applied to women who had moderate to severe wrinkles at the periorbital region. All of the experiments were conducted with retinol as a reference. RS-2A was more stable than retinol to thermal conditions, especially in solution. Both RS-2A and retinol were unstable to light, but RS-2A showed enhanced photo-stability with regard to concentration, more polar solvent, and addition of proper excipients. RS-2A exhibited decreased cytotoxicity and enhanced effects on collagen synthesis compared with retinol. In a clinical study, a 4-week treatment with RS-2A significantly improved the appearance of periorbital wrinkles without any side effects. The results indicate that RS-2A might have potential as an anti-aging agent for cosmeceutical preparations because of its enhanced chemical stability, biological activity, safety, and clinical efficacy.

Antioxidant activity of polysaccharide purified from Acanthopanax koreanum Nakai stems in vitro and in vivo zebrafish model.

In this study, the antioxidative effects of a purified polysaccharide isolated from the stems of Acanthopanax koreanum Nakai (ASP) on hydrogen peroxide-induced oxidative stress was investigated both in vitro and in vivo using a zebrafish model. A. koreanum Nakai stem was hydrolyzed using five carbohydrases and five proteases for the enzyme-assistant extraction. Of the enzyme-assistant extracts, the Protamex extract exhibited the highest yield and a potent scavenging activity against free radicals. Ethanol-added separation and anion exchange chromatography were conducted to identify the active polysaccharide. The purified polysaccharide significantly scavenged hydrogen peroxide and reduced hydrogen peroxide-induced cell death in Vero cells and in zebrafish. The results reveal that ASP is a useful antioxidant polysaccharide and might be available for relevant industrial applications.

Polymeric vehicles for topical delivery and related analytical methods.

Recently a variety of polymeric vehicles, such as micelles, nanoparticles, and polymersomes, have been explored and some of them are clinically used to deliver therapeutic drugs through skin. In topical delivery, the polymeric vehicles as drug carrier should guarantee non-toxicity, long-term stability, and permeation efficacy for drugs, etc. For the development of the successful topical delivery system, it is of importance to develop the polymeric vehicles of well-defined intrinsic properties, such as molecular weights, HLB, chemical composition, topology, specific ligand conjugation and to investigate the effects of the properties on drug permeation behavior. In addition, the role of polymeric vehicles must be elucidated in in vitro and in vivo analyses. This article describes some important features of polymeric vehicles and corresponding analytical methods in topical delivery even though the application span of polymers has been truly broad in the pharmaceutical fields.

Preparation of a capsaicin-loaded nanoemulsion for improving skin penetration.

Capsaicin o/w nanoemulsions with enhanced skin permeation were successfully prepared by controlling the ratios of the surfactant mixtures, oleoresin capsicum as the oil phase, and aqueous phase. Oleoresin capsicum contains 22.67 mg/g of capsaicin, which is an active and oil-soluble ingredient. Nonionic surfactants, Tween 80 and Span 80, were used to optimize the weight ratio of surfactant mixtures (85.98:14.02) by calculating the hydrophile-lipophile balance (HLB) value. The optimal processing conditions for stable nanoemulsions were investigated by using a ternary phase diagram. The mean droplet size of nanoemulsions ranged from 20 to 62 nm. Skin permeation studies were performed using a Franz diffusion cell. The permeation profiles and confocal laser scanning microscopy (CLSM) images supported that capsaicin nanoemulsion could well permeate all skin layers from the stratum corneum to the dermis. The selected nanoemulsions showed great potential as transdermal delivery carriers for enhancing the permeation of core materials.

In vitro and in vivo antioxidant activities of polysaccharide purified from aloe vera (Aloe barbadensis) gel.

The in vitro and in vivo antioxidant potentials of a polysaccharide isolated from aloe vera gel were investigated. Enzymatic extracts were prepared from aloe vera gel by using ten digestive enzymes including five carbohydrases and five proteases. Among them, the highest yield was obtained with the Viscozyme extract and the same extract showed the best radical scavenging activity. An active polysaccharide was purified from the Viscozyme extract using ethanol-added separation and anion exchange chromatography. Purified aloe vera polysaccharide (APS) strongly scavenged radicals including DPPH, hydroxyl and alkyl radicals. In addition, APS showed a protective effect against AAPH-induced oxidative stress and cell death in Vero cells as well as in the in vivo zebrafish model. In this study, it is proved that both the in vitro and in vivo antioxidant potentials of APS could be further utilized in relevant industrial applications.

Cyclohexanediol bis-ethylhexanoate inhibits melanogenesis of murine B16 melanoma and UV-induced pigmentation in human skin.

The role of cyclohexane diester analogues in the formation of melanin has been recently reported. In the present study, we investigated the inhibitory effect of cyclohexanediol bis-ethylhexanoate (CHEH) on melanogenesis in B16 melanoma cells and on UV-B-induced pigmentation in human skin. CHEH significantly reduced the melanin content in a dose-dependent manner, without cytotoxic effects at the effective concentrations. Moreover, CHEH dose-dependently inhibited tyrosinase activity in B16 melanoma cells, as confirmed by Western blot analysis of the tyrosinase protein levels. However, tyrosinase transcript levels remained unchanged under the same experimental conditions. These results indicate that CHEH inhibited melanogenesis in B16 melanoma cells by regulating tyrosinase activity at the post-transcriptional level. On the other hand, in a cell-free system, CHEH did not inhibit tyrosinase activity. This indicated that CHEH suppressed the pigmentation of melanocytes by indirectly regulating tyrosinase activity. Finally, in a clinical trial, a cream containing 1.0% CHEH showed good whitening effect on UV-induced pigmented human skin without adverse effects. In conclusion, we suggest that CHEH may be an effective inhibitor of melanogenesis and useful effects in the treatment of hyperpigmented disorders.

Topical delivery of retinol emulsions co-stabilised by PEO-PCL-PEO triblock copolymers: effect of PCL block length.

This article describes enhanced skin permeation and UV/thermal stability of retinol emulsions by the co-stabilisation of Tween20 and biodegradable poly(ethylene oxide)-block-poly(ε-caprolactone)-block-poly(ethylene oxide) (PEO-PCL-PEO) triblock copolymers having different lengths of hydrophobic PCL block. A triblock copolymer with a longer PCL block has a lower hydrophile-lipophile balance (HLB) value. Commercial Retinol 50C® (BASF Co., Ludwigshafen, Germany) was used as the source of retinol. Ultrasonication of the Retinol 50C® emulsion with the triblock copolymers led to an increase in retinol solubilisation and a decrease in average particle size of the resulting retinol emulsion. These characteristics improved skin permeation of retinol through the stratum corneum of artificial skin and subsequent proliferation of viable epidermis cell. Employment of the triblock copolymer with a longer PCL block increased both UV and thermal stabilization of the retinol. These results suggest that HLB and PCL block length are important factors to enhance the topical delivery of retinol into the skin.

Synthesis and characterization of PEO-PCL-PEO triblock copolymers: effects of the PCL chain length on the physical property of W(1)/O/W(2) multiple emulsions.

A series of poly(ethylene glycol)-block-poly(epsilon-caprolactone)-block-poly(ethylene glycol) (PEO-PCL-PEO) triblock copolymers were prepared and then used for the investigation of the effects of the ratio of epsilon-caprolactone to poly(ethylene glycol) (i.e., [CL]/[EO]) on the physical properties of water-in-oil-in-water (W(1)/O/W(2)) multiple emulsions containing a model reagent, ascorbic acid-2-glucoside (AA2G). In the synthesis, the [CL]/[EO] was varied from 0.11 to 0.31. The molecular weights and compositions of PEO-PCL-PEO were determined by GPC and (1)H NMR analyses. Thermal behavior and crystal formation were studied by DSC, XRD, FT-IR, and polarized optical microscopy (POM). Aggregate behavior of PEO-PCL-PEO was confirmed by DLS, UV, and (1)H NMR. Morphology and relative stiffness of the W(1)/O/W(2) multiple emulsions in the presence of PEO-PCL-PEO were studied by confocal laser scanning microscopy (CLSM) and rheometer. Variation in the [CL]/[EO] significantly affects the crystalline temperature and spherulite morphology of PEO-PCL-PEO. As the [CL]/[EO] increases, the CMCs of PEO-PCL-PEO decreases and the slope of aggregate size reduction against the copolymer concentration becomes steeper except for the lowest [CL]/[EO] value of PEO-PCL-PEO (i.e., P-222). P-222 significantly increases the viscosity of continuous (W(2)) phase, which implies the copolymer would exist in the W(2) phase. On the other hand, the triblock copolymers with relatively high [CL]/[EO] ratios mainly contribute to the size reduction of multiple emulsions and the formation of a firm wall structure. The particle size of the multiple emulsion decreases and the elastic modulus increased as [CL]/[EO] increases, confirmed by microscopic and rheometric analyses.

CDNA array analysis of gene expression profiles in brain of mice exposed to manganese.

This study is performed to detect changes of gene expression in substantia nigra (SN) and striatum in manganese (Mn)-exposed mice brain. The cDNA array is a recently developed molecular biological method that can detect the differential expression of several hundreds of genes simultaneously and is therefore advantageous in the study of trace metal intoxication effect at the genetic level. Using this technology, we discovered 5 genes in the mouse striatum and 9 genes in SN changed by more than 50% following Mn exposure. Depression were observed in two genes (neural cell adhesion protein BIG2, heavy neurofilament subunit genes) in striatum and three genes (light neurofilament subunit, brain acyl-CoA synthetase II, heavy neurofilament subunit genes) in the SN. However three genes (N-acetylglucosaminyltransferase I, S100beta, and synaptonemal complex protein I genes) in striatum and six genes (noggin, striatin, Ost oncogene, S100beta, calcium/calmodulin-dependent protein kinase kinase beta, and N-acetylglucosaminyltransferase I genes) in SN were elevated following Mn exposure. Immunohistochemical study revealed that protein levels of S100beta also increased following Mn treatment. Activated astrocytes overexpressing S100beta are invariably and intimately associated with decreased expression of heavy and light neurofilament subunits which is a distinguishing feature of neurodegeneration by Mn exposure. All our findings suggested that neuronal degenerations occur in SN as well as striatum of mice exposed to Mn.