Synthesis and physical properties of petroselinic based estolide esters

A new series of petroselinic (Coriandrum sativum L.) based estolide 2-ethylhexyl (2-EH) esters were synthesized, as the capping material varied in length and in degrees of unsaturation, in a perchloric acid catalyzed one-pot process with the esterification process incorporated into an in situ second step to provide the coriander estolide 2-EH ester. The kinematic viscosities ranged from 53 to 75 cSt at 40 °C and 9.1 to 14.6 cSt at 100 °C with a viscosity index (VI) ranging from 151 to 165. The caprylic (C8) capped coriander estolide 2-EH ester had the lowest low-temperature properties (pour point = −33 °C and cloud point = −33 °C), while the coco-coriander estolide 2-EH ester produced an estolide with modest low-temperature properties (pour point = −24 °C and cloud point = −25 °C). The coco-coriander estolide 2-EH ester was explored for the ability to resist oxidative degradation with the use of an biodegradable additive package added in 1.5%, 3.5%, or 7.0% units based on weight. The oxidative stability increased as the amount of stability package increased (rotating pressurized vessel oxidation test (RPVOT) times 65-273 min). Along with expected good biodegradability, these coriander estolide 2-EH esters had acceptable properties that should provide a specialty niche in the U.S. as a biobased lubricant.     

Improvement of three popular Indian groundnut varieties for foliar disease resistance and high oleic acid using SSR markers and SNP array in marker-assisted backcrossing

Foliar fungal diseases(rust and late leaf spot)incur large yield losses,in addition to the deterioration of fodder quality in groundnut worldwide.High oleic acid has emerged as a key market trait in groundnut,as it increases the shelf life of the produce/products in addition to providing health benefits to consumers.Marker-assisted backcrossing(MABC)is the most successful approach to introgressing or pyramiding one or more traits using traitlinked markers.We used MABC to improve three popular Indian cultivars(GJG 9,GG 20,and GJGHPS 1)for foliar disease resistance(FDR)and high oleic acid content.A total of 22 BC3F4 and 30 BC2F4 introgression lines(ILs)for FDR and 46 BC3F4 and 41 BC2F4 ILs for high oleic acid were developed.Recurrent parent genome analysis using the 58 K Axiom_Arachis array identified several lines showing upto 94%of genome recovery among second and third backcross progenies.Phenotyping of these ILs revealed FDR scores comparable to the resistant parent,GPBD 4,and ILs with high(~80%)oleic acid in addition to high genome recovery.These ILs provide further opportunities for pyramiding FDR and high oleic acid in all three genetic backgrounds as well as for conducting multi-location yield trials for further evaluation and release for cultivation in target regions of India.     

美国大花生脂肪酸的遗传分析

Ｆ４３５作高油酸亲本与１２个美国大花生品种配制杂交组合,并以大花生为轮回亲本回交３次。结果表明,花生高油酸（８０％左右）性状由两对隐性基因控制。在在美国大花生种质资源中,两对显、隐性基因杂合的种质普遍存在,而隐性纯合形式的种质很少。Ｆ２和回交后自交ＢＣｎ＋１Ｓ１代群体出现３（正常油酸含量）：１（高油酸含量）的分离比例,两对隐性基因除控制高油酸性状外,对勘察农艺性状无影响。花生棕榈酸、油酸和亚油酸的     

Effects of microfluidization on microstructure and physicochemical properties of corn bran

Corn bran was treated by the microfluidization process and the resulting changes in its microstructure and physicochemical properties were examined. The results showed that the microfluidization process could effectively decrease particle size of corn bran and loosen microstructure of the bran matrix. This led to a significant decrease in bulk density and increases in specific surface area. The swelling capacity, water-holding capacity, oil-holding capacity, and cation-exchange capacity increased by 140%, 90%, 140%, and 90%, respectively, after a total of 8 passes through the IC₂₀₀ and IC₈₇ chambers. In addition, microscopic analysis revealed a gradual disintegration of original cell wall structure and the dissociation of different bran tissues as the extent of microfluidization treatment increased. Findings of this study highlighted the great potential of the microfluidization process in producing a high-quality fiber ingredient from corn bran.     

Effect of germination time on physicochemical properties of brown rice flour and starch from different rice cultivars

The present work was designed to obtain information on the effect of germination time on the selected physicochemical properties of brown rice flour and starch prepared from three different rice cultivars. Changes in total starch, amylose and amylopectin contents of flour, amylopectin/amylose ratio and molecular weight of starch, gelatinization, pasting, rheological, and morphological properties of flour and starch during 5 days of germination were investigated. Significant changes of pasting and rheological properties of brown rice flour were found during germination, but only small changes of these properties could be found in isolated starch. Scanning electron micrographs of flour showed that the continuous matrix structure of flour was highly destroyed after germination and scanning electron micrographs of isolated starch showed that after three days of germination, pits and holes were discovered on the surface of some starch granules. Germination had little effect on the average molecular weight of starch, but the polydispersity value in germinated brown rice (2–5 days germination) was higher than that in non-germinated brown rice. The changes observed in physicochemical properties of brown rice flour and starch after germination provided a crucial basis for understanding flour and starch modification mechanisms with potential applications for an industrial scale.     

Improving the barrier and mechanical properties of corn starch-based edible films: Effect of citric acid and carboxymethyl cellulose

The films produced from pure starch are brittle and difficult to handle. Chemical modifications (e.g. cross-linking) and using a second biopolymer in the starch based composite have been studied as strategies to produce low water sensitive and relatively high strength starch based materials. A series of corn starch films with varying concentrations (0-20%, W/W) of citric acid (CA) and carboxymethyl cellulose (CMC) were produced by casting method. The effects of CA and CMC on the water vapor permeability (WVP), moisture absorption, solubility and tensile properties were investigated. The water vapor barrier property and the ultimate tensile strength (UTS) were improved significantly (p < 0.05) as the CA percentage increased from 0 to 10% (W/W). At the level of 15% (W/W) CMC, the starch films showed the lowest WVP values (2.34 × 10⁻⁷ g Pa⁻¹ h⁻¹ m⁻¹) and UTS increased from 6.57 MPa for the film without CMC to 16.11 MPa for that containing 20% CMC.     

Analysis of linoleic acid hydroperoxides generated by biomimetic and enzymatic systems through an integrated methodology

An integrated methodology for the identification and quantification of linoleic acid hydroperoxides (HPODEs) mixtures, obtained by the Fenton's reaction and by enzymatic oxidation, is reported. Unambiguous identification of the HPODEs formed (13-hydroperoxy-(9Z,11E)-octadecadienoic acid, 13-hydroperoxy-(9E,11E)-octadecadienoic acid and 9-hydroperoxyoctadecadienoic acid) was performed by HPLC-MS/MS analysis, while quantification was carried out by HPLC-UV using an external calibration, based on the collection of chromatographic peaks, and measuring of total hydroperoxides by ferrous oxidation-xylenol orange (FOX) method.     

Moisture distribution of soaked rice grains observed by magnetic resonance imaging and physicochemical properties of cooked rice grains

Moisture distribution in individual polished rice grains was observed during soaking by magnetic resonance (MR) imaging, and a nuclear magnetic resonance (NMR) signal intensity profile (SI-profile) was generated from the MR image. The water penetration pattern during soaking roughly showed dissimilar trends between different varieties of japonica and japonica-indica hybrid rice. NMR signal intensity at the completion of water absorption varied within each grain; high at the periphery and the central region and low in the area between the periphery and the central region. High moisture content within the central region is due to loosely packed starch granules. The SI-profile was congruent for grains of the same variety harvested in different regions and years and characterized a grain moisture distribution for each variety. Moisture distribution was compared using SI-profiles for varieties with different amylose contents and new varieties bred for specific end-uses in Japan. The NMR signal intensity, which is related to the moisture content, at the surface of soaked grain was negatively correlated to the grain amylose content. The NMR signal intensities at the surface of soaked grain negatively correlated with the overall hardness of the cooked rice grain as measured by the single-grain low-high compression test.     

Physical properties of zein films containing salicylic acid and acetyl salicylic acid

Zein films containing salicylic acid (SA) and acetyl salicylic acid (ASA) between 2 and 10% (initial zein weight basis) with or without glycerol were evaluated for structure, mechanical and dissolution properties. The random coils, α helices and β sheets mainly governed the secondary structure of zein, depending on glycerol and level of model molecules. Adding ASA resulted in an increase in α helices whereas β sheets increased at the expense of α helices when SA was used. Including SA or ASA decreased the tensile strength and the stiffness of films containing glycerol indicating the synergistic effect of SA and ASA. The strain at failure decreased with increasing content of SA but increased with increasing level of ASA. The dissolution properties were glycerol and drug dependent. ASA release in comparison to SA was quite low. The release was only observed above 10% ASA whereas it was detected in all films containing SA. The possible interactions between active components and proteins are discussed together with their implications on the physical properties of zein films.     

Synthesis and physical properties of pH-sensitive semi-IPN hydrogels based on poly(dimethylaminoethyl methacrylate-co-PEG dimethacrylate) and poly(acrylic acid)

Hydrogels of semi-interpenetrating polymer networks (semi-IPNs) were prepared by two step reactions. Dimethylaminoethyl methacrylate (DMAM) and poly(ethylene glycol)-dimethacrylate (PEGDM) were copolymerized to yield hydrogels, and then acrylic acid (AA) monomer were adsorbed in the hydrogels followed by polymerization of AA to produce semi-IPNs. The swelling behavior of semi-IPNs depends largely on pH of medium, showing that the degree of swelling of the semi-IPNs exhibits a minimum at pH 6.0. It is observed that the elastic modulus of semi-IPNs is closely related to its swelling behavior.     

Proximate composition and selected physicochemical properties of the seed,pulp and oil of sour sop (Annona muricata)

Proximate composition and physicochemical analyses were carried out onthe seed, pulp and extracted oil of sour sop (Annona muricata). Theresults showed that the seed contained 8.5% moisture, 2.4% crudeprotein, 13.6% ash, 8.0% crude fiber, 20.5% fat and 47.0%carbohydrate. The seed also contained 0.2% water soluble ash, 0.79%titratable acidity and 17.0 mg calcium/100 g. The pulp was found tocontain 81% moisture, 3.43% titratable acidity and 24.5%non-reducing sugar. Selected physicochemical characteristics includedrefractive indices of 1.335 for the seed and 1.356 for the pulp, specificgravities of 1.250 for the seed and 1.023 for the pulp, pH values of 8.34for the seed and 4.56 for the pulp, and soluble solids contents of1.5 ^°Brix for the seed and 15 ^°Brix for the pulp. Theextracted oil (20.5% yield) had a 60.43% unsaponifiable value,23.54 KOH/g acid value, 100.98 K0H/g saponification value, 1.1 K0H/gperoxide value, 1.464 refractive index, 5.77 pH, 69.5 ^°Brix soslublesolids and 0.2900 specific gravity.     

Dough rheological properties and texture of gluten-free pasta based on proso millet flour

Proso millet (PM) is a gluten-free cereal grain with potential to be used in gluten-free product development. However, research on improving the rheological properties of PM dough is limited. In the present study, rheological and color characteristics of PM dough (37% moisture) were compared with the behavior of wheat dough. Three hydrocolloids [guar gum (GG), xanthan gum (XG) and sodium alginate (SA)] at concentrations of 0%, 1% and 2% were added to improve the physical properties of PM dough. The textural properties of PM dough developed pasta with hydrocolloids were also studied. Wheat dough presented a much higher apparent viscosity and elastic modulus than PM dough. Both the apparent viscosity and elasticity were increased by all three hydrocolloids, with 2% XG presenting the most pronounced improvement in elasticity. Generally, the capacity of hydrocolloids to improve the PM dough follow the order XG > GG > SA. The addition of hydrocolloids showed no significant impact on the color of PM dough. GG and XG showed an improvement in the network strength of PM pasta, while SA did not contribute to textural enhancement.     

The effect of ultrasound upon the physicochemical and emulsifying properties of wheat and soy protein isolates

The effect of ultrasound upon the physicochemical and emulsifying performance of wheat protein isolate (WhPI) and soy protein isolate (SPI) was investigated. Protein solutions (0.1–3 wt. %) were sonicated with an acoustic intensity of ∼34 W cm⁻² for 2 min. The physicochemical properties were assessed in terms of changes in protein aggregate size, hydrodynamic volume and molecular structure. The emulsifying performance of ultrasound treated WhPI and SPI was compared to their untreated counterparts, and a low molecular weight surfactant, Tween 80, for comparative purposes. Ultrasonic processing significantly reduced the aggregate size of both proteins, whilst no reduction in the primary structure molecular weight profile was observed in both instances, ascribed to insufficient energy to hydrolyse the peptide bond. Emulsions prepared with both untreated proteins yielded submicron emulsion droplets (∼150 nm) at concentrations ≥ 0.75 wt. %. Emulsions fabricated with both sonicated proteins at concentrations <0.75 wt. % demonstrated significantly (P < 0.05) smaller emulsion droplets and long term emulsion stability in comparison to their untreated counterparts. This effect is consistent with the observed reduction in the equilibrium value of interfacial tension between untreated and ultrasound treated proteins.     

The nutritional properties of extruded and non-extruded corn fiber isolate

The feed efficiency and selected organ weights of rats fed diets containing 3 or 7% corn fiber, extruded corn fiber or silica were compared to rats fed a fiber-free diet. No significant differences were found in feed efficiency, spleen, lung or liver weights for any of the treatments relative to the fiber-free control diet.     

Improving effect of lyophilization on functional properties of resistant starch preparations formed by acid hydrolysis and heat treatment

In this study, effects of lyophilization on the functional properties of acid modified and autoclaved corn starch preparations were investigated. RS contents and pasting properties of these starch preparations were also determined. Significant increases in solubility were observed as the hydrolysis level of the lyophilized samples increased. All of the acid-modified gelatinized–autoclaved–lyophilized samples had higher water binding values than those of native starch and heat treated oven-dried native starch. Acid-modified gelatinized–autoclaved–lyophilized samples (with storage at 95°C: GASL or without storage: GAL, before lyophilization) improved emulsion properties of soy protein solution significantly. Acid modification seems to be a prerequisite to achieve improving effect of lyophilization. While native starch did not contain any RS, the level increased to 8.1% due to gelatinization, autoclaving and oven-drying (Control 2). The RS content of Control 2 was higher than that of gelatinized–autoclaved–lyophilized native starch (N-GAL, 2.9%). The samples stored prior to lyophilization had higher RS contents as compared to the corresponding unstored samples. The highest RS content (12.4%) was observed in 2h-GASL sample. Cold viscosity was observed in the RVA curves of N-GASL, 2h-GASL, N-GAL and 2h-GAL samples. A possible mechanism/model is suggested to explain the lack or existence of a cold viscosity.     

The effects of puroindoline b on the ultrastructure of endosperm cells and physicochemical properties of transgenic rice plant

Endosperm texture is an important factor governing the end-product quality of cereals. The texture of wheat (Triticum aestivum L.) endosperm is controlled by puroindoline a and b genes which are both absent in rice (Oryza sativa L.). It has been reported that the endosperm texture of rice can be modified by puroindoline genes. The mechanism, however, by which puroindolines affect the ultrastructure of rice endosperm cells remains to be investigated. In this study, we observed the ultrastructure of endosperm cells and the morphology of isolated starch granules of the transgenic rice expressing the puroindoline b gene. SEM and TEM observations indicated that compound starch granules were embedded within the matrix material in non-transgenic rice, Nipponbare, whereas they were surrounded by spaces in the transgenic rice. The morphology and size of each starch granule were not different between non-transgenic and the transgenic rice. However, the transgenic rice flour showed smaller particle size, higher starch damage, and lower viscosity during gelatinization than that of non-transgenic rice. These results confirm that puroindoline b reduces the grain hardness in rice. Moreover, the results also suggest that puroindoline b functions at the surface of compound starch granules, and not on polygonal starch granules in rice endosperm.     

The effect of infrared stabilized rice bran substitution on physicochemical and sensory properties of pan breads: Part I

Infrared stabilized rice bran (SRB) substitution to white wheat, wheat bran and whole grain wheat breads at the levels of 2.5, 5.0 and 10.0% was evaluated in terms of proximate composition, crumb color, dietary fiber, texture and sensory attributes. An increasing tendency was observed in crude fat and ash content of the breads. Redness (+a*), yellowness (+b*) chroma and redness (a*/b*) values were increased gradually with the addition of SRB. Crumb color was found to be darker when 10% of SRB was added to the breads. SRB inclusion did not affect the content of soluble dietary fiber while it significantly increased the insoluble and total dietary fiber contents of the breads (p < 0.05). In general, whole grain wheat bread differed from the other bread types in terms of textural behavior. Based on the overall acceptability scores, white wheat and wheat bran breads were sensory accepted up to 10% of flour replacement with rice bran, while substitution levels higher than 2.5% negatively affected the sensory scores of whole grain wheat bread.     

Improvement of mechanical and electrical properties of poly(ethylene glycol) and cyanoresin based polymer electrolytes

Ionic conductivity and mechanical properties of a mixed polymer matrix consisting of poly(ethylene glycol) (PEG) and cyanoresin type M (CRM) with various lithium salts and plasticizer were examined. The CRM used was a copolymer of cyanoethyl pullulan and cyanoethyl poly(vinyl alcohol) with a molar ratio of 1:1, mixed plasticizer was ethylene carbonate (EC) and propylene carbonate (PC) at a volume ratio of 1:1. The conductive behavior of polymer electrolytes in the temperature range of 298∼338 K was investigated. The PEG/LiClO₄ complexes exhibited the highest ionic conductivity of ∼10⁻⁵ S/cm at 25°C with the salt concentration of 1.5 M. In addition, the plasticized PEG/LiClO₄ complexes exhibited improvement of ionic conductivity. However, their complexes showed decreased mechanical properties. The improvement of ionic conductivity and mechanical properties could be obtained from the polymer electrolytes by using CRM. The highest ionic conductivity of PEG/CRM/LiClO₄/(EC-PC) was 5.33×10⁻⁴ S/cm at 25°C.     

甘草酸及甘草苷的提取纯化方法和药理作用研究进展

通过查阅国内外文献资料,总结了甘草酸与甘草苷的提取纯化方法,以及二者的药理作用。可为以后更深入系统研究甘草酸与甘草苷的药理活性提供理论依据,为二者的新药开发提供参考。     

Mechanical properties of semi-interpenetrating polymer network hydrogels based on poly(2-hydroxyethyl methacrylate) copolymer and chitosan

Semi-interpenetrating polymeric network (semi-IPN) hydrogels based on poly(2-hydroxyethyl methacrylate) (PHEMA) and poly(2-hydroxyethyl methacrylate-co-sodium methacrylate) [P(HEMA-co-SMA)], and chitosan with different molecular weights were prepared by crosslinking with ethylene glycol dimethacrylate (EGDMA) and poly(ethylene glycol) diacrylate (PEGDA) and their gelation time, water content, mechanical properties, and morphology were investigated. In consideration of the influence of the molecular weight of chitosan, there is no big difference in the water content, while tensile properties and compressive modulus increased as the molecular weight of chitosan increased. The water content increased and tensile properties and compressive modulus decreased with increasing SMA concentration. Considering the effect of the crosslinking agent, PEGDA had higher water content and lower tensile and compressive moduli than EGDMA. It is suggested that PHEMA/chitosan and P(HEMA-co-SMA)/chitosan semi-IPN hydrogels with different structures and physical properties can be prepared depending on the molecular weight of chitosan, the copolymerization with SMA, and the crosslinking agent type.