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Dry edible beans (Phaseolis vulgaris) represent an inexpensive way to incorporate protein into the diet as a food ingredient, but beans contain unpleasant flavors and several anti-nutritional factors that limit their use without first processing with long heat treatments. `Great Northern' bean flour was processed using either static or specially designed dynamic (continuous) processing methods. The dynamic process treated flour slurries at temperatures up to 124°for 20 sec. The slurries were quick-frozen and freeze-dried after frozen storage periods of 0, 8, 24, 120, or 504 hr. The flours were analyzed for sensory properties, emulsifying activity, foaming properties, and trypsin inhibition. The heat treatments improved sensory attributes of the flour. The foam capacity and foam stability decreased in heat-treated flours. Trypsin inhibitor activity was at a minimum level immediately following thermal processing, but increased with time in frozen storage prior to drying. Minimal thermal processes cannot be relied upon to inactivate trypsin inhibitors.
Many plants can produce bioactive chemicals with medicinal or health benefits, which has stimulated a whole new research effort aimed at extracting & improving natural phytochemicals. Begonia is a rich source of biologically-active phytochemicals and an excellent donor for natural anthocyanin pigments. High levels of triterpene compounds and a host of potentially-useful flavonoids have been isolated from Begonia sp., which may account for its frequent use as a medicinal plant remedy in a diverse array of cultures worldwide. Deliberate shifting of the physical and chemical microenvironments can have a significant effect on anthocyanins and precursors produced in vitro. This realization offers the potential to thoroughly screen and study valuable phytochemicals from Begonia. Begonia genotypes from 3 species were screened to identify callus induction techniques. Contamination inherent in the vascular system of one genotype, along with spontaneous organogenesis, were found to be recurrent problems. These were partially alleviated by light and growth regulator treatments. Studies comparing callus and in vitro vegetative tissues as resources for phytochemical extraction are scheduled.
Interactions between irradiance levels (5–40 μmol·m-2·s-1) and iron chelate sources (FeEDTA and FeEDDHA) were observed for Carica papaya shoot tip cultures during both the establishment and proliferation stages of microculture. Reduced levels of irradiance (5 μmol·m-2·s-1) favored shoot tip establishment regardless of the source or level of iron. However, the highest percentage of successful explant establishment (100%), and significantly greater leaf length (1.16 cm; over double the size attained in any other treatment), resulted when a low concentration of FeEDTA alone was used at low irradiance. During the subsequent shoot proliferation stage, however, higher irradiance levels (30 and 40 μmol·m-2·s-1) were required, and FeEDTA failed to support culture growth when used as the sole iron source. The highest multiplication rates (3.6 shoots per explant) and leaf chlorophyll concentrations (0.22 mg/g fresh mass), and significantly improved shoot quality were achieved at 30 μmol·m-2·s-1 irradiance when both iron chelate formulations were combined (each at a 100 μM concentration) in the proliferation medium. Chemical names used: benzylamino purine (BA); ferric disodium ethylenediamine tetraacetate or FeNa2EDTA (FeEDTA); ferric monosodium ethylenediamine di(o-hydroxyphenylacetate), (FeNaEDDHA) or Sequestrene 138Fe (FeEDDHA); indoleacetic acid (IAA); 1-naphthaleneacetic acid (NAA).
Polyphenolic compounds (particularly anthocyanins, proanthocyanidins, and other flavonoids) from some fruits and vegetables have significant and diverse impacts on human health preservation. While it's well recognized that some of the polyphenolics in foods we consume have a protective and proactive role against disease, very little has been known about how they accomplish this feat. A range of bioassays (in vitro and in laboratory animals) were adapted to examine compounds extracted from berry fruits, and separated into distinct fractions by vacuum chromatography. The proanthocyanidin class of compounds, as well as mixtures of proanthocyanidins and other flavonoids, were significantly bioactive against both the promotion and initiation stages of chemically-induced carcinogenesis. Potent antioxidant activity was not confined to particular fractions, but was present in several classes of compounds. Identification and characterization of the bioflavonoids is complicated both by apparent interactions between related compounds that occur together within horticultural fruits, and interferences from some substances (pectins and complex sugars) that depress observed response in bioactivity assays.
Abstract
Roots of sweet potato [Ipomoea batatas (L.) Lam.] and beet (Beta vulgaris L.) peeled with superheated steam, had higher peel and trim yields than did those peeled with saturated steam at the same pressure. Product recovery was greater with all steam-peeling methods than with caustic peeling. Direct injection of cold water into the partially pressurized steam atmosphere of the peeler also increased product recovery. Better color retention in processed beets was obtained from steam-peeled roots than from caustic-peeled roots.
Abstract
Nitrogen and K were applied to 26-year-old ‘Western’ pecan [Carya illinoensis (Wangenh.) C. Koch] trees at 0, 56, 112, or 224 kg ha−1, and 0, 93, or 186 kg ha−1, respectively, for 6 consecutive years (1978–1983). There was a positive relationship between N rate and leaf N concentration and shoot growth. The number of new shoots per 1-year-old shoot was increased by N application. Yield was greater using 56, 112, or 224 kg N ha−1 than no N. Nitrogen rate was negatively related to leaf K concentration and curvilinearly related to leaf Mn concentration, but did not affect leaf Ca or Mg. Leaf P and Zn concentrations were reduced during some years by N application. Potassium application increased leaf K concentration in 1980, 1982, and 1983, but did not affect leaf K concentration in other years. Surface applied K moved to the 30–45 cm depth by 1980 and to the 45–60 cm depth by 1982. Potassium rate was positively related to leaf Mn concentration, but not leaf N, P, Ca, Mg, or Fe concentration. Annual yield was increased by K rate only in 1979, but cumulative yield was positively related to K rate.
Industrial-scale cultivation of plant cells for valuable product recovery (e.g. natural pigments, pharmaceutical compounds) can only be considered commercially-feasible when a fully-automated, predictable bioprocess is achieved. Automation of cell selection, quantification, and sorting procedures, and pinpointing of optimal microenvironmental regimes can be approached via machine vision. Macroscopic staging of Ajuga reptans callus masses (ranging between 2-6 g FW) permitted simultaneous rapid capture of top and side views. Area data used in a linear regression model yielded a reliable, non-destructive estimate of fresh mass. Suspension culture images from the same cell line were microscopically imaged at 4x (with an inverted microscope). Using color machine vision, the HSI (hue-saturation-intensity) coordinates were used to successfully separate pigmented cells and aggregates from non-pigmented cells, aggregates, and background debris. Time-course sampling of a routine suspension culture consistently allowed pigmented cells to be detected, and intensity could be correlated with the degree of pigmentation as verified using spectrophotometer analysis of parallel samples.
A 12-week greenhouse experiment was undertaken to test the efficiency of inoculation of vesicular-arbuscular mycorrhizal fungi on four apple (Malus domestica Borkh) rootstock cultivars: M.26, Ottawa 3 (Ott.3), P.16, and P.22. The plants were grown in soil from an apple rootstock nursery, containing high levels of extractable P (644 kg Bray/1 ha-1). Inoculation treatments were Glomus aggregatum Shenck and Smith emend. Koske, G. intraradix Shenck and Smith, and two isolates of G. versiforme (Karsten) Berch, one originally from California (CAL) and the other one from Oregon (OR). Mycorrhizal plants were taller, produced more biomass, and had a higher leaf P concentration than the uninoculated control plants. Mycorrhizal inoculation also significantly increased the leaf surface area of `M.26' and `Ott.3' compared to the control. Glomus versiforme(CAL)-inoculated plants generally had the best nutrient balance, the greatest final height and shoot biomass, and produced an extensive hyphal network. All the mycorrhizal plants had similar percentages of root colonization, but the size of the external hyphal network varied with fungal species. Glomus versiforme(OR) had a larger extramatrical phase than G. aggregatum and G. intraradix. Mycorrhizal efficiency was associated with a larger external hyphal network, but showed no relation with internal colonization. Despite the high P fertility of the soil used, growth enhancement due to mycorrhizal inoculation was attributed to improved P nutrition.
Herbicides are increasingly used in orchards. Since apple trees strongly depend on mycorrhizae, the effects of three commonly used herbicides on the host plant and endophyte were examined. Symbiosis between tissue-cultured P16 apple rootstocks and Glomus versiforme (Karsten) Berch was established under greenhouse conditions. Simazine (1, 2, 10, and 20 μg a.i./g), dichlobenil (1, 5, 10, and 25 μg a.i./g), paraquat (0.5, 1, 10, and 100 μg a.i./g), or water was applied to mycorrhizal and nonmycorrhizal plants as a soil drench. The response of mycorrhizal plants to herbicide was greater, and the relative elongation rate was more sharply reduced in mycorrhizal (76%) than in nonmycorrhizal plants (33%). Six weeks after herbicide application, dry mass reduction due to herbicides was similar (39% and 36%) for mycorrhizal and nonmycorrhizal plant shoots, respectively, while root dry mass reduction was larger for mycorrhizal (63%) than nonmycorrhizal plants (46%). None of the herbicide treatments affected root colonization. However, an in vitro hyphal elongation test with G. intraradices Schenck & Smith and herbicide-amended (0, 1, 10, 100, and 1000 μg a.i./g) gellan gum solidified water showed that either dichlobenil or paraquat, even at the lowest concentrations, could significantly reduce hyphal elongation. Simazine did not affect hyphal elongation in vitro, a result suggesting that improved absorption capacity of mycorrhizae explains, at least in part, the increased phytotoxicity of some herbicides. It was found that plant mortality was higher among mycorrhizal than nonmycorrhizal apple trees for all herbicide treatments. The increased CO2 assimilation rates of dichlobenil-treated mycorrhizal plants contrasted with the decreased rates of control plants measured 1 week after dichlobenil treatment. This indicates a physiological interaction between mycorrhizal colonization and dichlobenil in the toxic response of apple plants. Chemical names used: 2-chloro-4,6-bis-ethylamino-s-triazine (simazine), 2,6-dichlorobenzonitrile (dichlobenil), 1,1'-dimethyl-4,4'bipyridinium (paraquat).
Carbonated water (CW) application has enhanced yields of tomato. However, little is known about the mechanism of this response. Our objectives were to determine if strawberry would respond to CW application and the effect of soil pH modification on the expression of a yield response. Two different soils were used; a calcareous soil (5% CaCO3, pH 7.9), with a Zn content 0.8 ppm and a non-calcareous soil (< 1% CaCO3, pH 6.5) with a Zn content 8.8 ppm. The carbonated water temporarily lowered the pH of the calcareous soil to 6.7 and the non-calcareous soil to 5.9, at both extremes of the optimal range (6.0-6.7) for strawberry. Application of carbonated water increased production of marketable fruit as compared to the tap water control on both soils, and the magnitude of the response to CW was similar for both soils. Soil and water treatment effects on leaf tissue Zn levels will also be discussed.