Effects of oxygen tension in the gas atmosphere during in vitro maturation, in vitro fertilization and in vitro culture on the efficiency of in vitro production of mouse embryos

Effects of oxygen (O2) tension in the gas atmosphere during in vitro maturation (IVM), in vitro fertilization (IVF) and in vitro culture (IVC) on the efficiency of in vitro production of mouse embryos were examined. Mouse oocytes recovered from large antral follicles were subjected to IVM in Waymouth medium for 15, 16 and 17 hr under 5 or 20% O2 and then subjected to IVF and IVC under 5 or 20% O2 tension. Lowering the O2 tension in the gas atmosphere for IVM from 20 to 5% improved the cleavage rate after IVF when the oocytes were subjected to IVM for 15 hr; however, no improvement in the cleavage rate was observed when the culture period for IVM was extended to 16 and 17 hr. Lowering the O2 tension to 5% for IVM and IVC improved the development of the cleaved oocytes to the blastocyst stage, regardless of the culture period for IVM. However, the O2 tension for IVF had no remarkable effect on the subsequent embryonic development. These results demonstrate that 5% O2 is superior to 20% O2 for IVM and IVC, and suggest that 20% O2 for IVM may delay oocyte maturation and/or the acquisition of fertilizability and impair the developmental competence of oocytes.     

The Applicability of the Local and International Water Quality Guidelines to Al-Gassim Region of Central Saudi Arabia

The quality of 109 water samples, comprised of 70 drinking waterand 39 irrigation water samples, in Al-Gassim Region of SaudiArabia was investigated with respect to total dissolved salts(TDS), electric conductivity (EC), pH, total hardness and themajor cations (Ca²⁺, Mg²⁺, Na⁺ and K⁺) andanions (Cl^-, SO₄ ^2-, NO₃ ^-,F^- andHCO₃ ^-) beside coliform bacteria as an indicator offaecal contamination.The concentrations of TDS varied widely, from 109 to 6995 mgL^-1, with a mean of 1427 mg L^-1. Of the 109 watersamples examined, 81 (74.3%) comply with the maximumpermissible drinking water limits set by the local and international standards and guidelines and 28 (25.7%) were abovethe limits of these standards. The concentrations of the cationsand anions (with the exception of NO₃ ^- and F^-)follow, more or less, a trend similar to TDS. NO₃ ^- concentrations (range 0–30 mg L^-1) comply with the limitof 50 mg L^-1 NO₃ ^- as the highest tolerableNO₃ ^- content. The concentrations of F^- indrinking water (range 0.2–1.5 mg L^-1) are alarming since88% of samples were below the lower permissible limit of 0.6 mgL^-1 set by SASO (1984), the guideline of the WHO is 1.5 mgL^-1 while the EEC maximum concentration lies within the range 0.7–1.5 mg L^-1. Microbiological analyses showednegative coliform tests, which confirms that they are devoid ofany faecal contamination.     

Effect of biuret on the transformation of urea in two egyptian soils

In model experiments (60 % water holding capacity and 30°C) with a loamy clay (pH 8.3) and a calcareous sand (pH 7.9) the effect of biuret upon the breakdown of urea was studied. Ammonification and nitrification occured very quickly, in case of the calcareous sand at the beginning more NH₄ was evolved. Biuret in concentration from 0.4 to 8 % maximum did not influence urea hydrolysis, however it resulted in higher NO₂-figures at the beginning of the experiments demonstrating an initial marked inhibition of the process NO₂ → NO₃ especially in the calcareous sand. The total nitrification seemed to be a little retarded but did not differ very much finally.     

Physicochemical and Structural Characteristics of Flours and Starches from Waxy and Nonwaxy Wheats

A waxy spring wheat (Triticum aestivum L.) genotype was fractionated into flour and starch by roller and wet‐milling, respectively. The resultant flour and starch were evaluated for end‐use properties and compared with their counterparts from hard and soft wheats and with commercial waxy and nonwaxy corn (Zea mays L.) starches. The waxy wheat flour had exceptionally high levels of water absorption and peak viscosity compared with hard or soft wheat flour. The flour formed an intermediate‐strength dough that developed rapidly and was relatively susceptible to mixing. Analysis by differential scanning calorimetry and X‐ray diffractometry showed waxy wheat starch had higher gelatinization temperatures, a greater degree of crystallization, and an absence of an amylose‐lipid complex compared with nonwaxy wheat. Waxy wheat and corn starches showed greater refrigeration and freeze‐thaw stabilities than did nonwaxy starches as demonstrated by syneresis tests. They were also similar in pasting properties, but waxy wheat starch required lower temperature and enthalpy to gelatinize. The results show analogies between waxy wheat and waxy corn starches, but waxy wheat flour was distinct from hard or soft wheat flour in pasting and mixing properties.     

Study on furundu, a traditional Sudanese fermented roselle (Hibiscus sabdariffa L.) seed: effect on in vitro protein digestibility, chemical composition, and functional properties of the total proteins

Furundu, a meat substitute, is traditionally prepared by cooking the karkade (Hibiscus sabdariffa L.) seed and then fermenting it for 9 days. Physicochemical and functional properties of raw and cooked seed and of furundu ferments were analyzed. Furundu preparation resulted in significant changes in karkade seed major nutrients. Total polyphenols and phytic acid were also reduced. The increase in total acidity and fat acidity coupled with a decrease in pH indicates microbial hydrolysis of the major nutrients; proteins, carbohydrates, and fats. In vitro digestibility of the seed proteins reached the maximum value (82.7%) at the sixth day of fermentation, but thereafter it significantly decreased. The effect of furundu preparation on N solubility profiles and functional properties, such as emulsification and foaming properties and other related parameters, is investigated in water and in 1 M NaCl extracts from defatted flour samples. The results show that cooking followed by fermentation affects proteins solubility in water and 1 M NaCl. The foaming capacity (FC) from the flour of raw seed decreased as a result of cooking. Fermentation for 9 days significantly increased the FC of the cooked seed, restoring the inherent value. Foam from fermented samples collapsed more rapidly during a period of 120 min as compared to the foam from raw and cooked karkade seeds; stability in 1 M NaCl was lower as compared to those in water. In water, the emulsion stability (ES) from the fermented samples was significantly higher than that of the raw seed flour. Addition of 1 M NaCl significantly decreased the ES of the fermented samples.     

Effect of gamma-irradiated entomopathogenic nematodeSteinernema carpocapsae (Fil.) on the larvae of the potato tuber moth,Phthorimaea operculella (Zell.)

The effect of gamma irradiation on the pathogenicity of the entomopathogenic nematodeSteinernema carposapsae was studied by infecting the larvae of the potato tuber moth,Phthorimaea operculella. Full grown larvae of the host were gamma-irradiated with different doses ranged from 2.5 to 160 Gray (Gy) and subsequently infected with either unirradiated or irradiated infective juveniles (IJs) ofS. carpocapsae using the same doses. For comparison, two groups of unirradiated and irradiated host larvae were left without nematode infection. Another group of larval host was also infected with nematodes either unexposed or exposed to the previous doses.The results revealed that there was a rapid mortality in the irradiated host infected with either unexposed nematodes or nematodes irradiated with different doses similar to the mortality in the nematode treatment alone. On the other hand, the pathogenicity of the nematodes was affected as a result of gamma irradiation with high doses, i. e. irradiation of nematodes delayed their efficiencyvis à vis the unirradiated host. However, lower doses of gamma irradiation exhibited worthily stimulating effect on the pathogenic nematodes, one week post irradiation, as it reduced by half the period of time required for killing all irradiated host larvae with regard to nematode treatment alone. Furthermore, nematode treatment whether applied alone or combined with gamma irradiation appears very promising as compared with single irradiation treatment of the host.With 3 tables     

Effects of Cumin and Ginger as Antioxidants on Dough Mixing Properties and Cookie Quality

The effects of cumin and ginger as antioxidants on dough mixing properties and cookie quality were evaluated. Antioxidant activities in cookies were estimated by total phenolic compounds (TPC) contents and free radical scavenging activities. The cookie dough development was evaluated using Mixolab equipment which showed that addition of cumin did not change dough stability and C2, but decreased C3 and C4. While the addition of 5% ginger decreased dough stability (from 8.4 in the control sample to 6.7 min with 5% ginger addition), C2 (from 0.49 in the control sample to 0.31 N·m with 5% ginger addition), C3, and C4. Cookies formulated with addition of cumin and ginger had increased spread ratios, were softer, and had lower L* and b* values (were darker) than the control. Sensory analysis showed that cookies with cumin and ginger additions had overall acceptability similar to that of the the control with a slightly darker appearance, as confirmed by color determination. Using cumin and ginger significantly increased TPC contents from 78.5 in the control to 93.0 and 109.8 mg of gallic acid equivalent/100 g, respectively. Similar results were observed in the antioxidant activity measured by 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH), which increased from 41.0% in the control to 51.5% and 64.6%, respectively, for cookies with 5% addition of cumin and ginger.     

Response of nitrogen fixation,nodule activities,and growth to potassium supply in water‐stressed broad bean

Three‐week‐old nodulated faba bean plants were subjected to two levels of water stress (0.5 and 0.25 field capacity; soil water content of 20 and 10%) for five weeks. Half of the stressed plants was treated with potassium chloride (KC1) at 10 (K₁) and 150 mg (K₂)/kg soil at the beginning of water deficit. Nodulation was examined and some nodule activities were assayed. Nodulation, nitrogenase activity, total nitrogen (N), and dry matter yield were significantly decreased by increasing stress but were significantly higher with the two levels of potassium (K) supply. Leghaemoglobin and protein contents of cytosol as well as nodule protease and invertase were severely depressed by drought stress. Soluble carbohydrate contents of nodules, however, was significantly increased. Protein and leghaemoglobin contents and enzyme activities were greater with K fertilization but less soluble carbohydrate was accumulated. The results indicate that K supply, particularly at the 150 mg/kg soil level, increased faba bean resistance to water stress.