This work is a continuation of our earlier studies on the effects of commercial processing methods, as used in Britain, upon the nutritive value of milk(i-i3). It had two main objectives: one was to add to the existing knowledge by including measurements of factors which were either unknown at the time of the earlier investigations or for which satisfactory methods of measurement other than biological have only recently been evolved; the other was to study the effects of new methods and recent modifications of existing ones.Of late the general trend in milk processing has been towards the application of increasingly higher temperatures for short periods of time in various pre-treatments and also towards the use of high temperature in the main treatments themselves. In view of the heat lability of many nutritionally important constituents of milk, the nutritive effects of these new methods obviously demanded study.The paper deals with, seven vitamins of the B complex in seven heat-treated milk products made from one bulk of raw milk. METHODS Bulk milk.A bulk of 170 gal. of whole milk predominantly from Shorthorn and Friesian cows was obtained from a commercial dairy within 20 miles of the Dairy Department of Reading University. There it was emptied into an insulated stainless steel tank fitted with a mechanical agitator, and stored overnight at about 5° C. After thorough mixing, samples were withdrawn for processing when the milk was between 24 and 36 hr. old. With the exception of the ultra-high temperature (U.H.T.) sterilization, which was done at the National Institute for Research in Dairying, all treatments were done at the Dairy Department of Reading University on a commercial or pilot-plant scale.Pasteurized milk (H.T.S.T. process). Eighty gallons of milk were pasteurized at 72° C. (holding for 15 sec.) in a commercial A.P.V. plate-type heat exchanger and the milk was sampled after having been cooled to about 5° C.Sterilized milk (in-bottle process). Four gallons of milk were brought within 10 min. to 71-1° C. and then homogenized at a pressure of 2500 lb./in-2 and dispensed into pint bottles which were sealed immediately with ' Crown' corks of the type normally used. The bottles were heated in a steam autoclave for 30 min., some at 107-2° C. and others at 111° C. 192 Milk processing and some vitamins of the B complexSterilized milk (U.H.T. process). Fifty gallons of milk were brought within 18 sec. to 85° C, homogenized in a two-stage homogenizer at 500 and 2000 lb./in. 2 within about 23 sec. and sterilized by the ultra-high temperature process in an A.P.V. 200 gal./hr. HX plate-type stainless steel commercial plant. The milk was heated in it within 18-5 sec. to 135° C. and held at this temperature for about 2 sec. before cooling to 20° C. One gallon of this processed milk was dispensed into pint bottles, which were then sealed with ' Crown' corks and heated to 107-2° C. for 20 min. The second sterilization was necessary to simulate commercial conditions in which there is still no satisfactory method for a...
The spinosyns are a novel family of fermentation-derived natural products that exhibit potent insecticidal activities. Spinosad, a naturally-occurring mixture of spinosyn A and spinosyn D, has successfully established its utility for crop protective applications in the agrochemical field. Potential applications of this unique chemical family of macrolides also have been investigated in the field of animal health. Applications for the control of blowfly strike and lice on sheep have now been commercially developed and registered in Australia and potential applications for the control of ectoparasites on cattle are being studied.
Dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 produced by UC 1 1065 were evaluated as anthelmintics. Assays used to examine these compounds included effects on the free-living nematode Caenorhabditis elegans, ability to clear target nematodes {Haemonchus contortus and Trichostrongylus colubriformis) from jirds, and clearance of Haemonchus contortus from lambs. A crude extract of UC 11065 containing dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 was active against C. elegans and against H. contortus in the jird. Purified and/or synthetic samples of dioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2 were tested in the jird model; only dioxapyrrolomycin exhibited appreciable activity against H. contortus (^90.9% clearance at 0.33mg/jird), while none of the compounds showed appreciable activity against T. colubriformis. Dioxapyrrolomycin cleared 99.9% of H. contortus from lambs at 12.5 mg/kg. An in vitro migration study using susceptible and closantel-resistant H. contortus showed there is cross-resistance between dioxapyrrolomycin and closantel. Dioxapyrrolomycin appears to be a narrow-spectrum anthelmintic which works through a closantel-like mode-of-action. 977 In the course of screening for novel metabolites active against brine shrimp, Anemiasalina, a soil actinomycete (#9041 3, subsequently UC 1 1065) was found which produces a mixture ofdioxapyrrolomycin, pyrrolomycin C, pyrrolomycin D, and piericidin C2. The principal components produced during fermentation were evaluated in a battery of anthelmintic assays, and one of these components, dioxapyrrolomycin, was found to have appreciable anthelmintic activity. Results of those studies are reported herein. Materials and Methods Producing OrganismThe dioxapyrrolomycin-producing, actinomycete culture was isolated from soil obtained in Michigan, U.S.A. It was given accession number UC11065 in The Upjohn Culture Collection. The culture was stored as 4 mmdiameter agar plugs of vegetative growth (medium ISP-2, Difco) in a liquid nitrogen vapor phase freezer. Fermentation ConditionsAll fermentations were carried out in 500-ml wide-mouth Erlenmeyer flasks containing 100 ml media on a rotary shaker (250rpm, 3.8cm throw) at 28°C. The source of inoculum consisted of four 4mm diameter agar plugs (medium ISP-2, Difco) containing well-sporulated mycelial growth. This was placed in a seed medium (25 g/liter Cerelose, 25 g/liter Pharmamedia, pH 7.2 using ammoniumhydroxide), and the seed culture was incubated for 72 hours. The seed culture served as inoculum (5% v/.v rate) for shake 978 THE JOURNAL OF ANTIBIOTICS JUNE 1992 flasks containing a production medium (20 g/liter D-galactose, 20 g/liter dextrin, lO g/liter Soytone (Difco), 2.5 g/liter Solulys (Roquette), 2 g/liter (NH4)2SO4, 2 g/liter CaCO3, pH 7.2 using potassium hydroxide). Tap water was used in preparation of seed and production media. Production cultures were incubated for 96 hours prior to harvesting.Isolation and Purification (Scheme 1) Silica Co...
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