scholarly journals Olive paste oil content on a dry weight basis (OPDW): an indicator for optimal harvesting time in modern olive orchards

2016 ◽  
Vol 67 (2) ◽  
pp. e137 ◽  
Author(s):  
A. Dag ◽  
I. Zipori ◽  
A. Bustan ◽  
Z. Kerem
Keyword(s):  
Oil Content ◽  
Dry Weight ◽  
Weight Basis ◽  
Optimal Harvesting ◽  
Harvesting Time

scholarly journals Investigation of the Optimal Harvesting Time in Some Iranian and Mediterranean Olive Cultivars Based on Their Oil Content and Fatty Acid Compositions

2016 ◽  
Vol 6 (19) ◽  
pp. 85-96
Author(s):  
F. Razeghi Jahroomi ◽  
S. M. Hosseini Mazinani ◽  
SH. Mohammadi ◽  
KH. Razavi ◽  
B. Shiran ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Oil Content ◽  
Optimal Harvesting ◽  
Harvesting Time ◽  
Olive Cultivars ◽  
Fatty Acid Compositions

ERRORS ASSOCIATED WITH HERBAGE DISSECTION ANALYSES 2. Problems of species identification

1976 ◽  
pp. 213-225
Author(s):  
I.M. Ritchie ◽  
C.C. Boswell ◽  
A.M. Badland
Keyword(s):  
New Zealand ◽  
Dry Weight ◽  
Analytical Tool ◽  
Species Level ◽  
Weight Basis ◽  
Plant Identification ◽  
Leaf Fragment ◽  
Research Division ◽  
Or Groups ◽  
Botanical Analysis

HERBACE DISSECTION is the process in which samples of herbage cut from trials are separated by hand into component species. Heavy reliance is placed on herbage dissection as an analytical tool ,in New Zealand, and in the four botanical analysis laboratories in the Research Division of the Ministry of Agriculture and Fisheries about 20 000 samples are analysed each year. In the laboratory a representative subsample is taken by a rigorous quartering procedure until approximately 400 pieces of herbage remain. Each leaf fragment is then identified to species level or groups of these as appropriate. The fractions are then dried and the composition calculated on a percentage dry weight basis. The accuracy of the analyses of these laboratories has been monitored by a system of interchanging herbage dissection samples between them. From this, the need to separate subsampling errors from problems of plant identification was, appreciated and some of this work is described here.

Polycyclic Aromatic Hydrocarbons (PAHs) in Sediments of the Brisbane River (Australia) – Preliminary Results

1989 ◽  
Vol 21 (2) ◽  
pp. 161-165 ◽  
Author(s):  
S. I. Kayal ◽  
D. W. Connell
Keyword(s):  
Polycyclic Aromatic Hydrocarbons ◽  
Aromatic Hydrocarbons ◽  
River Estuary ◽  
Dry Weight ◽  
Weight Basis ◽  
Sediment Samples ◽  
Preliminary Results ◽  
Treated Sewage ◽  
Polycyclic Aromatic ◽  
Petroleum Refineries

Results of the analysis of twenty-three composite sediment samples revealed that PAHs are widely distributed in the Brisbane River estuary. Mean concentrations for individual compounds, on a dry weight basis, ranged from 0.03 µg/g for dibenz [ah] anthracene to 2.34 µg/g for fluoranthene. Observed PAH assemblages were rich in compounds having pyrolytic origins. However, the presence of petroleum derived compounds was indicative of the importance of petroleum as a PAH source in the estuary. Petroleum refineries, a coal loading terminal and a major treated sewage outfall located at the mouth were not indicated as major contributing sources of PAH pollution in the estuary.

Mineral nutrition, dinitrogen fixation, and growth of Alnuscrispa and Alnusglutinosa

1985 ◽  
Vol 15 (5) ◽  
pp. 855-861 ◽  
Author(s):  
G. Prégent ◽  
C. Camiré
Keyword(s):  
Mineral Nutrition ◽  
Dry Weight ◽  
Optimal Growth ◽  
Maximum Growth ◽  
Dinitrogen Fixation ◽  
Weight Basis ◽  
Critical Levels ◽  
N Status

Invitro cultures of Alnuscrispa (Ait.) Pursh and Alnusglutinosa (L.) Gaertn. were used to estimate critical foliage levels of selected nutrients for optimal growth and dinitrogen (N2) fixation. For A. crispa to obtain 90% of maximum growth and N2 fixation, foliar levels of 0.12% P, 0.13% Mg, <0.31% K, and <0.04% Ca on a dry weight basis were needed. For A. glutinosa, the critical levels were 0.138% P, 0.10% Mg, 0.29% Ca, and ~0.20% K. From all the deficiencies observed, P had the more pronounced effects on N status of both species.

SOLUBLE SUGAR CHANGES OCCURRING DURING COLD HARDENING OF SPRING WHEAT, FALL RYE AND ALFALFA

1983 ◽  
Vol 63 (2) ◽  
pp. 415-420 ◽  
Author(s):  
D. G. GREEN
Keyword(s):  
Spring Wheat ◽  
Soluble Sugar ◽  
Soluble Sugars ◽  
Dry Weight ◽  
Weight Basis ◽  
Cold Hardening ◽  
Spring Type

Alfa, a relatively nonhardy alfalfa cultivar continued to accumulate, on a dry weight basis, fructose, α- and β-D-glucose, sucrose and maltose during the latter stages of cold hardening. Rambler, a hardier alfalfa cultivar conversely showed a decrease for these soluble sugars with hardening. Frontier rye, a very hardy winter habit cereal showed decreases in these soluble sugars plus melibiose during the same hardening period. These results support the hypothesis that hardy cereals and alfalfa undergo a decrease in soluble sugars with hardening, while less hardy cereals and alfalfa continue to increase in content of soluble sugars. Manitou wheat appeared not to fit this hypothesis and showed the decreased soluble sugars usually associated with hardy cultivars. Although Manitou is a spring type wheat, one of its parents, Thatcher, does contain gene(s) for the winter habit.Key words: Sugar, cold hardening, wheat, rye, alfalfa

scholarly journals THE MOLECULAR WEIGHT OF RHODOPSIN AND THE NATURE OF THE RHODOPSIN-DIGITONIN COMPLEX

1954 ◽  
Vol 37 (3) ◽  
pp. 381-399 ◽  
Author(s):  
Ruth Hubbard
Keyword(s):  
Molecular Weight ◽  
Single Molecule ◽  
Extinction Coefficient ◽  
Dry Weight ◽  
Weight Basis ◽  
Sedimentation Behavior ◽  
A Value ◽  
Wet Weight ◽  
Single Boundary ◽  
Stoichiometric Complex

The sedimentation behavior of aqueous solutions of digitonin and of cattle rhodopsin in digitonin has been examined in the ultracentrifuge. In confirmation of earlier work, digitonin was found to sediment as a micelle (D-1) with an s20 of about 6.35 Svedberg units, and containing at least 60 molecules. The rhodopsin solutions sediment as a stoichiometric complex of rhodopsin with digitonin (RD-1) with an s20 of about 9.77 Svedberg units. The s20 of the RD-1 micelle is constant between pH 6.3 and 9.6, and in the presence of excess digitonin. RD-1 travels as a single boundary also in the electrophoresis apparatus at pH 8.5, and on filter paper at pH 8.0. The molecular weight of the RD-1 micelle lies between 260,000 and 290,000. Of this, only about 40,000 gm. are due to rhodopsin; the rest is digitonin (180 to 200 moles). Comparison of the relative concentrations of RD-1 and retinene in solutions of rhodopsin-digitonin shows that RD-1 contains only one retinene equivalent. It can therefore contain only one molecule of rhodopsin with a molecular weight of about 40,000. Cattle rhodopsin therefore contains only one chromophore consisting of a single molecule of retinene. It is likely that frog rhodopsin has a similar molecular weight and also contains only one chromophore per molecule. The molar extinction coefficient of rhodopsin is therefore identical with the extinction coefficient per mole of retinene (40,600 cm.2 per mole) and the E(1 per cent, 1 cm., 500 mµ) has a value of about 10. Rhodopsin constitutes about 14 per cent of the dry weight, and 3.7 per cent of the wet weight of cattle outer limbs. This corresponds to about 4.2 x 106 molecules of rhodopsin per outer limb. The rhodopsin content of frog outer limbs is considerably higher: about 35 per cent of the dry weight, and 10 per cent of the wet weight, corresponding to about 2.1 x 109 molecules per outer limb. Thus the frog outer limb contains about five hundred times as much rhodopsin as the cattle outer limb. But the relative volumes of these structures are such that the ratio of concentrations is only about 2.5 to 1 on a weight basis. Rhodopsin accounts for at least one-fifth of the total protein of the cattle outer limb; for the frog, this value must be higher. The extinction (K500) along its axis is about 0.037 cm.2 for the cattle outer limb, and about 0.50 cm.2 for the frog outer limb.

Influence of Temperature and Water Activity on Aflatoxin Production by Aspergillus flavus in Cowpea (Vigna unguiculata) Seeds and Meal

1985 ◽  
Vol 48 (12) ◽  
pp. 1040-1043 ◽  
Author(s):  
P. E. KOEHLER ◽  
L. R. BEUCHAT ◽  
M. S. CHHINNAN
Keyword(s):  
Heat Treatment ◽  
Water Activity ◽  
Aspergillus Flavus ◽  
Vigna Unguiculata ◽  
Dry Weight ◽  
Aflatoxin Production ◽  
Weight Basis ◽  
Influence Of Temperature

Experiments were done to determine the influence of temperature (21, 30 and 37°C) and aw (0.76 to 0.98) on aflatoxin production by Aspergillus flavus on cowpea (Vigna unguiculata) seeds, meal and meal supplemented with onion. Larger quantities of aflatoxin were produced at 21 and 30°C than at 37°C. The highest amount of aflatoxin (2777 μg/20 g, dry weight basis) was observed in meal containing onion at aw 0.98 after 20 d of incubation at 21°C. A level of 870 |μg/20 g was detected in seeds at aw 0.95 after 14 d of incubation at 30°C. Meal at aw 0.96 supported production of 551 μg of aflatoxin per 20 g after 20 d at 30° C. Temperature had little influence on the optimal aw for aflatoxin production in cowpea meal. However, an increase in temperature resulted in a decreased optimal aw for aflatoxin production on whole cowpeas. When known quantities of aflatoxin were added to cowpea meal which was subsequently steamed for 5 min, only 29% was extractable using a variety of procedures, indicating that the toxin may be bound in some manner to cowpea constituents as a result of heat treatment.

Low K+ in Paphiopedilum leeanum leaf epidermis: implications for stomatal functioning

1977 ◽  
Vol 55 (4) ◽  
pp. 489-495 ◽  
Author(s):  
Sherman D. Nelson ◽  
James M. Mayo
Keyword(s):  
Dry Weight ◽  
Atomic Absorption Spectrophotometry ◽  
Weight Basis ◽  
Leaf Epidermis ◽  
Photometric Analysis ◽  
Abaxial Epidermis ◽  
Absorption Spectrophotometry ◽  
Stomatal Functioning ◽  
Low K ◽  
Stomatal Mechanism

Abaxial epidermal strips from leaves of Paphiopedilum leeanum were analyzed via sodium cobaltinitrite staining and atomic absorption spectrophotometry for the presence and location of potassium. On a dry weight basis K content of the abaxial epidermis was found to be 103 times less than has been reported in other species, and unlike other species no localization of K+ in guard cells of open stomata could be detected via the sodium cobaltinitrite stain for potassium.Flame photometric analysis of the mesophyll indicated that it contained normal amounts of K+ (about 1.87% on a dry weight basis). Analysis showed that the K+ content of the abaxial epidermis (0.032%) was considerably less than that of the mesophyll, a situation unlike previous reports for other species in which the epidermal concentration was found to be greater than the mesophyll. A process for exclusion of K+ from the abaxial epidermis is suggested, as is the lack of involvement of K+ as the major osmoticum in the stomatal mechanism of this species.

LIPID AND MORPHOLOGICAL CHANGES IN DEVELOPING RAPESEED, BRASSICA NAPUS

1970 ◽  
Vol 50 (3) ◽  
pp. 233-247 ◽  
Author(s):  
D. B. FOWLER ◽  
R. K. DOWNEY
Keyword(s):  
Fatty Acid Composition ◽  
Fatty Acid ◽  
Brassica Napus ◽  
Erucic Acid ◽  
Seed Development ◽  
Acid Composition ◽  
Oil Content ◽  
Morphological Changes ◽  
Dry Weight ◽  
Dry Matter Accumulation

Self-pollinated seed from normal and erucic acid free plants of summer rapeseed (Brassica napus L.) was harvested at weekly intervals from pollination to maturity. Oven-dried whole seeds and their component parts were weighed and analyzed for oil content and fatty acid composition. Oil and dry matter accumulation followed sigmoidal patterns, most of the deposition occurring between 14 and 35 days after pollination (DAP). The relative contribution of the testa, endosperm and embryo to dry weight and oil content of whole seeds changed significantly during seed development. Oil content of the developing embryo varied from 22 to 44%, and the testa from 1.6 to 13%, although at maturity only 6 to 8% oil was found in the testa and adhering aleurone. The nucleate endosperm oil content was estimated to be low and in the order of 2 to 2.5%. In 7- to 14-day-old seeds the dry weight, oil content and fatty acid composition were largely determined by the testa and endosperm. From 14 to 21 DAP the testa and embryo were dominant and after 21 DAP the embryo was the controlling influence on the seed characteristics studied.Oils of the testa, nucleate endosperm and embryo differed in fatty acid composition. In seeds free of erucic acid, the ratios of the 18 carbon fatty acids of the embryo and testa remained nearly constant from 21 DAP to maturity. This suggested that the variation in fatty acid composition as well as oil content during seed development in this material was due to disproportionate changes in the contribution of the testa, nucleate endosperm and embryo. However, in developing seeds capable of producing erucic acid a change in the ratio of fatty acid synthesis occurred in both the testa and embryo.

scholarly journals Comparison of the Sub-Critical Fluid Extraction of the Essential Oil of Turmeric (Curcuma longa L.) with That of Hydrodistillation

Eng ◽  
2021 ◽  
Vol 2 (4) ◽  
pp. 608-619
Author(s):  
David Mc Gaw ◽  
Rosemarie Skeene
Keyword(s):  
Essential Oil ◽  
Curcuma Longa ◽  
Dry Weight ◽  
Weight Basis ◽  
Operating Conditions ◽  
Raw Material ◽  
Fluid Extraction ◽  
Total Extract ◽  
Pharmaceutical Properties ◽  
The Tropics

Turmeric (Curcuma longa L.) is a spice plant grown in the tropics that contains both an essential oil and an oleoresin. The essential oil is important as a flavouring and has pharmaceutical properties, while the oleoresin is bright yellow in colour and has medicinal properties. The essential oil has traditionally been extracted by hydrodistillation/steam distillation with the total extract being extracted by solvent extraction and more recently by supercritical fluid extraction (SFE). The objective of the work described in this paper was to investigate the possibility of extracting the essential oil using sub-critical fluid extraction and to compare it with hydrodistillation. The experiments using hydrodistillation showed that unpeeled fresh turmeric was the preferred raw material, giving an oil yield of ≈6% dry weight basis, which is similar to that reported in the literature. The experimental programme on the extraction of the oil from dried unpeeled turmeric was carried out over a temperature range from 25 to 30 °C and pressures from 65 to 71 bar. Yields were generally higher than hydrodistillation (up to ≈9% dry weight basis) as were the compositions of the extracted oils. The preferred operating conditions were determined to be 25 °C temperature and 65 bar pressure. Curcumin, the major component of the oleoresin, was not found in the oil, thereby demonstrating that the sub-critical extract is a pure essential oil. It is suggested that consideration be given to evaluating an SFE process whereby the essential oil is initially fully extracted under sub-critical fluid extraction conditions, after which the oleoresin is extracted separately by raising the pressure to ≈250 bar.

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