The effect of pretreatments on surfactin production from potato process effluent by Bacillus subtilis.

Pretreatments of low-solids potato process effluent were tested for their potential to increase surfactin yield. Pretreatments included heat, removal of starch particulates, and acid hydrolysis. Elimination of contaminating vegetative cells was necessary for surfactin production. After autoclaving, 0.40 g/L of surfactin was produced from the effluent in 72 h, vs 0.24 g/L in the purified potato starch control. However, surfactin yields per carbon consumed were 76% lower from process effluent. Removal of starch particulates had little effect on the culture. Acid hydrolysis decreased growth and surfactant production, except 0.5 wt% acid, which increased the yield by 25% over untreated effluent.

Biosurfactants from potato process effluents.

High-solids (HS) and low-solids (LS) potato process effluents were tested as substrates for surfactin production. Tests used effluents diluted 1:10, unamended and amended with trace minerals or corn steep liquor. Heat pretreatment was necessary for surfactin production from effluents due to indigenous bacteria, whose spores remained after autoclaving. Surfactin production from LS surpassed HS in all cases. Surfactin yields from LS were 66% lower than from a pure culture in an optimized potato starch medium. LS could potentially be used without sterilization for surfactin production for low-value applications such as environmental remediation or oil recovery.

Aneuploid marker assignment in hexaploid oat with the C genome as a reference for determining remnant homoeology.

Nullisomic lines of hexaploid oat Avena sativa L. (2n = 6x - 2 = 40, AACCDD) cultivar Sun II were used to assign 134 DNA sequences to 10 chromosome-associated syntenic groups. A limited set of ditelosomic lines allowed localization of subsets of these sequences to six chromosome arms. Advantages of using such aneuploids in mapping are in the assignment of gene families, monomorphic RFLP sequences, and oat linkage groups to chromosomes. The published hexaploid oat RFLP linkage map has 38 linkage groups, 17 more than expected on the basis of the haploid chromosome number. Using nullisomics, eight linkage groups were assigned to five physical chromosomes; using ditelosomics, three of these linkage groups were assigned to their respective chromosome arms. The A- and D-genome chromosome sets of oat are indistinguishable from each other based on different staining and genomic in situ hybridization techniques, while C-genome chromosomes are distinct. Because chromosomal rearrangements such as translocations and inversions have played an important role in the evolution of hexaploid oat, the distinction of C-genome chromosomes can be used to determine remnant homoeologous segments that exist in the other two genomes. Among the 10 syntenic groups identified, six chromosomes showed sequence homoeology believed to represent segmental homoeologous regions. Owing to various evolutionary forces, segmental homoeology instead of whole chromosome homoeology appears to best describe the genome organization in hexaploid oat.

Luteal morphology, atresia, and plasma progesterone concentrations during the reproductive cycle of two oviparous lizards, Crotaphytus collaris and Eumeces obsoletus.

From ovulation to oviposition, the corpora lutea of the oviparous lizards Crotaphytus collaris and Eumeces obsoletus exhibit three stages of luteal development: 1) luteogenesis, 2) luteal maturity, and 3) luteal regression. Each stage exhibits distinct characteristics, involving changes in: 1) luteal volume, 2) nuclear diameter of cells within the luteal cell mass, and 3) thecal development. Plasma progesterone concentration is greatest during luteogenesis and is positively correlated with ovarian atresia, although atresia occurred throughout the period of gravidity. These data suggest that in these two species, the corpora lutea secrete high amounts of progesterone immediately following ovulation and exhibit morphologically distinct stages of growth and regression.

Effect of deluteinization on plasma progesterone concentration and gestation in the lizard, Anolis carolinensis.

Plasma progesterone concentration in deluteinized female lizards, as determined by radioimmunoassay, did not decrease significantly, as compared to non-surgical controls until 48 hr after surgery. Sham surgery induced a significant increase in plasma progesterone concentration 24 hr after surgery. Progesterone concentration then declined to an intermediate level not significantly different from non-surgical control or deluteinized females. Plasma progesterone concentration in non-surgical control specimens exhibited no significant changes during the 96 hr in which animals were examined. Oviposition did not occur in the control or sham groups whereas three of eight of the deluteinized females did oviposit by 48 hr.

Oxymetazoline in the treatment of allergic and non-infectious conjunctivitis.

In a double-blind study of 141 patients, 0.025% oxymetazoline ophthalmic solution was compared with its vehicle in the treatment of allergic and non-infectious conjunctivitis. There was a marked difference in response at the first evaluation. By the tenth day (second evaluation) the total improvement in hyperaemia was 95% for oxymetazoline compared to 54% for the placebo. Oxymetazoline's decongestant effect in the eye matches its effect as a nasal vasoconstrictor.