Physico-Chemical Properties of Linseed Oil as Affected by Various Seed-Borne Fungi

The effect of six seed-borne fungi on linseed oil was studied. Alternaria alternate, Aspergillus flavus, Aspergillus repens, Fusarium culmorum and Torula allii reduced oil content while Cladosporum herbarum slightly increased it. All fungi increased the free fatty acid content and saponification number linseed oil. Iodine number was decreased except in Cladosporium herbarum and Fusarium culmorum. Aspergillus flavus was the most destructive parasite in altering quantity and quality of linseed oil.     

Effect of Seed-Borne Fusarium Species on the Physico-Chemical Properties of Rapeseed Oil

Fusarium oxysporum, F. moniliforme and F. semitectum isolated from Brassica campestris var. dichotoma seeds were grown on autoclaved seeds and after several weeks of incubation the oil was analysed. All the three Fusarium species reduced oil content and altered its colour. The infested oil emitted mouldy odour and the refractive index increased. The free fatty acid content increased progressively. The saponification value increased but the iodine value decreased.     

喜热噬油芽胞杆菌代谢产生表面活性剂的研究

采用丙酮抽提、高压液相分离纯化等技术从嗜热菌Geobacillus therm oleovorans以正十六烷为碳源培养的发酵液中分离获得性能突出的表面活性物质。利用甲脂化、乙酰化衍生技术结合GC-MS,MS(ESI)等鉴定该表面活性剂为单脂肪酸甘油脂。实验条件下,该表面活性剂使水的表面张力降低到32.7 mN/m,测定其临界胶束浓度为41 mg/L。     

Effect of Oil on the Population,Biomass, and Viability of Fungi in Highmoor Peats

Some microbiological parameters, such as the fungal mycelium length, the number of fungal spores, the distribution profiles of micromycetes, the viability of fungal propagules, the length distribution of micromycete hyphae, and the ratio between fungal spores and yeastlike cells, can be used to determine the degree of soil contamination with oil and the concentration that is inhibitory to micromycete complexes of highmoor peats.     

The Effect of Oil Contamination on the Geotechnical Properties of Fine-Grained Soils

Every day, petrochemical activities, oil spills, and pipeline or reservoir leakage contaminate the ground. In addition to environmental concerns, such as groundwater pollution, the alteration of geotechnical properties of the contaminated soil is also cause for worry. Contamination has been proven to alter the geotechnical properties of soil, and researchers have extensively studied the properties of contaminated granular soils. However, the effect of oil contamination on the geotechnical properties of fine-grained soils has not yet been well evaluated. Therefore, a comprehensive set of laboratory tests has been conducted on both uncontaminated and contaminated fine-grained soils containing different amounts of crude oil. The soil samples were taken from the lands in the vicinity of the Tehran oil refinery site where there is a vast area subjected to this problem.

The results of this study indicated that an increase in the angle of internal friction, maximum dry density, compression index, and Atterberg limits as well as a decrease in optimum water content and cohesion occur as the oil content increases. Moreover, aging caused a further decrease in cohesion but had no specific effect on the internal friction angle. These effects should be taken into consideration in the oil refinery site development programs. In addition, because treatment technologies for site clean-up are expensive, by investigating the geotechnical properties of contaminated soil, we are planning to develop methods of utilizing the soil as construction material.     

The Effect of VA Mycorrhizal Infection and Phosphorus Status on Sunflower Hydraulic and Stomatal Properties

Koide, R. 1985. The effect of VA mycorrhizal infection and phosphorusstatus on sunflower hydraulic and stomatal properties.—J. exp. Bot. 36: 1087–1098. Mycorrhizal (M) and non-mycorrhizal (NM) sunflower plants weregrown in a soil of low phosphorus availability (with and withoutphosphorus amendment) and in a soil of moderate phosphorus availability(without phosphorus amendment). Using the Ohm's law analogyand measured leaf water potentials, stem water potentials, andtranspiration rates, hydraulic resistances were calculated forthe whole plant, leaf, and below leaf components. Mycorrhizalinfection (as high as 89%) was shown to have no effect on theintrinsic hydraulic properties of the soil/plant system overa wide range of transpiration rates in either soil when M andNM plants of equivalent root length were compared. When grownin the soil of moderate phosphorus availability, calculatedhydraulic resistances under given environmental conditions werethe same for M and NM plants, as were stomatal resistances andtranspiration rates. When grown in the soil of low phosphorusavailability, calculated values of hydraulic resistance werelower for M plants than for NM plants under given sets of environmentalconditions. These differences in calculated hydraulic resistancewere not due to a difference in the intrinsic hydraulic propertiesof M and NM plants. The differences were evident because stomatalresistances were lower and transpiration rates higher for Mplants and because hydraulic resistance varied inversely withtranspiration rate. When plants of significantly greater rootlength were compared to plants of lesser root length, the calculatedhydraulic resistances under given environmental conditions weremuch lower for the plants of greater root length. This differencewas largely due to a difference in the intrinsic hydraulic propertiesbetween large and small plants, and not because of differencesin transpiration rate. The elevated transpiration rates exhibitedby M plants were attributed to an enhanced phosphorus status.Short term phosphorus amendments made to phosphorus-deficientNM plants improved transpiration; transpiration rates were similarfor M and NM plants before NM plants became phosphorus-deficient,and phosphorus-amended M and NM plants had similar transpirationrates. The data are discussed in relation to other reports ofmycorrhizal influence on hydraulic and stomatal resistances.Possible mechanisms for the influence of infection on stomatalresistance are also briefly discussed. Key words: Hydraulic resistance, stomatal resistance, mycorrhizas     

Comparative Study on the Ability of Different Oleogelators to Structure Sunflower Oil

Food Biophysics - In this research, the capability of different oleogelators (beeswax, rice bran wax and sunflower wax, stearic acid, octadecanol, γ-oryzanol+β-sitosterol mixture and...     

The Effect of Salinity on the Membrane Potential of Sunflower Roots

The effect of NaCl and Na₂SO₄ on the electrical potential difference(PD) across the membrane in the outer cortical cells of theroot of sunflower (Helianthus annuus) has been investigated.The effect on the PD of a range of concentrations of these saltsgiven as a shock treatment was compared with the long-term effectwhere plants were grown in a range of salinities for 2 weeks. Considerable effects on the PD were observed. In low concentrationsof salt (approximately 1 mM) the PD was enhanced whilst in highconcentrations there was a progressive reduction in the PD.Na2SO4 had a relatively greater effect on the PD than NaCl. Using a transient recorder it was possible to measure the PDacross the plasmalemma and the tonoplast separately. The PDacross the plasmalemma was found to be markedly affected bysalinity. The tonoplast PD was relatively small compared tothat across the plasmalemma and appeared to be little affectedby the salts.     

药用菌防治老年痴呆研究进展

老年痴呆是现代老龄社会的常见病,对社会和病人的家庭都有重大的影响,因此老年痴呆有效成分已成为当今人们关注的研究热点之一,国内外抗痴呆化学药物的研究已取得了一定的进步,但由于此类药物具有较大的毒副作用,而药用菌则具有天然性和低毒副作用等特点,因而已成为科学家新的研究方向。药用菌抗肿瘤和提高免疫力等保健功效的研究已引起广泛的关注,而关于其抗痴呆的研究报道则较少见。本文就目前药用菌抗痴呆的研究进展作一阐述。     

The Isolation of Collagenase and Its Enzymological and Physico-chemical Properties

A collagenolytic enzyme specific for native collagen and gelatin was isolated from Pseudomonas marinoglutinosa by DEAE-cellulose column chromatography, Sephadex G–150 gel filtration and by disc electrophoresis on polyacrylamide gel.

The molecular weight of the enzyme was approximately 74,000 and its isoelectric point was found to be around 4.5. The optimum pH and temperature for Z–GPLGP hydrolysis were around 7.6 and 38°C, respectively. The enzyme was rather stable up to 50°C and in the range between pH 5.0 and 10.0, and was stabilized by Ca²⁺ to some extent. Some chelating agents and metal ions such as Hg²⁺, Pb²⁺, Zn²⁺, Ni²⁺ and Fe²⁺ inactivated the enzyme, but diisopropyl phosphofluoridate, sulfhydryl agents and some trypsin inhibitors did not affect the activity.

The EDTA-inactivated enzyme was restored its activity by added Ca-salt to almost completely and very slightly by Co-, Mn- and Sr-salt.

Metal analysis showed the enzyme contained 1 g atom of zinc and 4 g atoms of calcium per mole.     

Effect of Oil Content and Composition on the Gelling Properties of Egg-SPI Proteins Stabilized Emulsion Gels

Effects of different oils on the rheological properties, textural profile, water loss (WL), oil loss (OL) and microstructure of egg-soybean protein isolate (SPI) stabilized emulsion gels were investigated at neutral pH, wherein soybean oil, olive oil and menhaden oil were used to form emulsions. The results showed that viscosity of emulsions progressively increased with the increase of oil content. Similarly, analysis of the rheological behavior of the formulated emulsion gels revealed an increase in the mechanical strength (G’) with the increase in oil concentration, indicating that oil droplets played a significant role in the formation of the gel structure. In addition, at high levels of oil, the hardness and chewiness of emulsion gels were also high, while a slight decrease in springiness and cohesiveness were observed. A linear relationship between hardness and water/oil loss was found, whereas the Pearson correlation suggested that less drainage of water may slow down the outflow of oil. The microstructural images showed a more compact network as a result of the increase of oil content in the formulation. Scarce significant differences were found among emulsion gels formulated with different oil type, suggesting oil composition played a dispensable role on the gelling properties of emulsion gels.

     

Modification of the Effect of Nitrosomethylurea on Sunflower Seedlings by Heat Shock

Separate and combined action of nitrosomethylurea (NMU) and heat shock (HS) on germination of seeds of the inbred line 3629 and derived nuclear and plastome mutant lines, n-chlorina-1 and en-chlorina-5, respectively, were studied. NMU at a concentration of 0.015%, as well as HS (40°C), had no effect on the spontaneous level of chromosome aberrations in root meristem of sunflower seedlings. However, at a concentration of 0.03%, the mutagen considerably increased the frequency of chromosome rearrangements. Pretreatment with heat for 30 min enhanced the cytogenetic effect of NMU (0.03%) on line 3629 seedlings. In the nuclear mutant, the reaction of root meristematic cells did not depend on the additional heat treatment. The combined action of HS and NMU at early germination stages had no effect on the survival of line 3629 plants and plastome mutant en-chlorina-5; the survival of n-chlorina-1 plants decreased. The highest frequency of M₁plants with chlorophyllic abnormalities (green revertants, lethals, and variegated forms) was observed in n-chlorina-1 line.     

The Effect of Seed-Borne Pathogens on Emergence of Globe Amaranth, Calendula and Tagetes and the Methods of Control

Nimbya gomphrenae , Stemphylium vesicarium and Alternaria tagetica were isolated for the first time from seeds of diseased globe amaranth ( Gomphrena globosa ), pot marigold ( Calendula officinalis ) and marigold ( Tagetes erecta ), respectively, in Taiwan. The amount of seed-borne N. gomphrenae or Colletotrichum dematium was positively correlated (P=0.05) with the amount of the abnormal seedling and unemergent seed of globe amaranth. Similarly, the amount of seed-borne Alternaria alternata or S. vesicarium was negatively correlated (P=0.05) with the emergent rate of pot marigold. Treating the fungi-contaminated globe amaranth seeds with Bacillus megaterium [1.3 × 10⁹colony-forming units (CFU)/ml] or 1% NaOCl significantly (P=0.05) increased seed emergence over control whereas 10 p.p.m. pyrifenox could control N. gomphrenae on globe amaranth. Stemphylium -contaminated pot marigold seeds responded to 200 p.p.m. iprodione treatment by increasing significantly (P=0.05) in seed emergence over untreated control. For seed-borne A. tagetica , treating marigold seeds with Bacillus azotoformanis (1 × 10⁹CFU/ml) was found effective and mancozeb highly effective.     

Effect of Formaldehyde on Fungi from Broiler Houses

S ummary . A comparison was made of the relative sensitivity to formaldehyde of the predominant fungi isolated from broiler house litter by treating conidia with aqueous solutions of formaldehyde for 45 min at 20–22°. Aspergillus sydowi and A. versicolor were most tolerant of formaldehyde, followed by A. repens, A. flavus , and A. candidus . Least tolerant were Scopulariopsis brevicaulis, A. ruber, A. chevalieri , and Penicillium crustosum . The viability of conidia of selected strains differing in tolerance to formaldehyde and the viability of fungi and bacteria in dust samples collected from commercial broiler houses were tested after exposure to gaseous formaldehyde at 2 p/m (approximate theoretical concentration attained in broiler houses) and 10 p/m (theoretical) (estimated concentration 5 p/m) for 24 h at 20–22° and 65% relative humidity. The viability of the asexual conidia was always < 0.01% whereas with the dust samples only 10 p/m of formaldehyde markedly reduced the viability of all of the microorganisms.     

Effect of Gibberellic Acid on the Distribution of Products of Photosynthesis in Sunflower

Single leaves on growing sunflower plants were allowed to assimilate¹⁴CO₂. Gibberellic acid was applied to the same leaf or to theterminal bud or the roots, and the distribution of assimilated¹⁴C was determined at intervals of 1–96 h. Gibberellicacid had no significant effect on initial distribution of ¹⁴Cduring the period of rapid export from the leaf, but enhancedre-export from the roots after translocation from the leaf hadvirtually ceased. Most of the ¹⁴C exported from the roots accumulatedin the shoot tip. The site of application of the hormone wasof relatively minor importance. Wherever it was applied themajor effect was enhancement of movement from the roots to theshoot tip. Application to the terminal bud was most effectivein this respect. There was no evidence that gibberellic aciddirectly affected the transport system, but the data supportthe hypothesis that it increases the strength of the sink inthe shoot tip. Helianthus annuus L., sunflower, assimilate transport, gibberellic acid, phloem transport     

Screening Diverse Fungi for Laccases of Varying Properties

Qualitative screening of 295 fungi for laccases yielded 125 laccase positive ones, mostly basidiomycetes. Fifty of these were tested for laccase activity at pH 3.0, 4.5 and 6.0. Most showed maximum activity at pH 4.5, a few showed a broad activity range, two were optimal at pH 3.0 and only the mitosporic fungus Beltraniella sp. was best at pH 6. Most of the 25 fungi assayed at three different temperatures had an optimum at 45°C. The basidiomycete Auricularia sp. acted best at 30°C, while three others showed best activity at 60°C. This study shows the potential of screening diverse fungi for laccase with varying pH and temperature preferences for different applications.     

Effect of the Shoot on the Transmembrane Potentials of Root Cortical Cells of Sunflower

Transmembrane potentials (PD) of root cortical cells were measuredbetween the vacuole and the external solution while the rootsremained attached to the plants. External solution concentrationwas varied by using a range of dilutions of a balanced nutrientsolution. In all cases the PD was more negative than that dueto diffusion alone indicating the presence of an electrogenicor metabolically derived component. This component contributedan additional –80 mV to the PD and was relatively independentof the external solution concentration. The metabolic componentwas eliminated by metabolic inhibitors, placing the shoot indarkness, ringing the phloem, or severing the rootlet from theshoot; it was restored again by removing the inhibitor, by light,or, in the case of severance, by adding 25 mM sucrose to themedium. The magnitude of the electrogenic component of the PDwas dependent on the antecedent light intensity in a way reminiscentof translocation itself.     

海水处理对向日葵幼苗生长及叶片一些生理特性的影响

采用海水水培的方法,比较了淡水、20%和40%海水处理对向日葵(Helianthus annuus L.)幼苗生长速率、根冠比、脯氨酸、丙二醛(MDA)含量和保护性酶超氧歧化酶(SOD)及过氧化物酶(POD)活性的影响.结果表明:20%海水处理显著地促进根系生长和根冠比的增加,大大地缓解了叶片的膜脂过氧化作用(使之降至与对照相当的水平),而40%海水明显抑制向日葵生长;脯氨酸在处理4 d后显著积累,40%海水处理后脯氨酸与MDA变化曲线相关性较强,表明脯氨酸的积累在本实验中表现为活性氧伤害的结果;40%海水处理对食葵叶片造成的过氧化伤害比油葵大,但食葵比油葵的自身修复受伤害膜系统的能力强.