Kinetics of the continuous hydrolysis of olive oil by Candida cylindracea lipase in a microporous hydrophobic membrane bioreactor (flat membrane or hollow fiber module) was studied. A general equation for outlet conversion was derived on the assumption that flow of oil is of plug-flow type when the reversible Michaelis-Menten equation was applied in “surface phase”. The cases of first-and zero-order kinetics and the diffusion-controlled case through micropores were also analyzed as limiting cases. The theoretical considerations indicate that the flow rate of oil divided by the total membrane area, F/A, is an important operating parameter which governs the performance of the microporous hydrophobic membrane bioreactor. Analyses of batch lipolysis data reported by three research groups showed that the hydrolysis reaction of oil obeyed the first-orded reversible kinetics. Experimental data for the flat membrane bioreactor (countercurrent operation) obtained by the authors agreed with the reversible first-order kinetics in a wide range of F/A, while the data for the hollow fiber module (countercurrent operation) agreed with the reversible first-order kinetics only at higher F/A. Lower rates of hydrolysis at lower F/A seemed to be due to non-uniform flow of oil through the hollow fibers. The new concept of “equivalent droplet size” is proposed to compare the performance of the membrane bioreactor system with that of the emulsion system.

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DL-threo- and DL-erythro-C_n-dihydrosphingosines (n=12, 14, and 16) were separated from the corresponding 2-amino-1, 3-alkanediols by repeated recrystallization of the N, O, O-triacetyl and N-acetyl derivatives. Ceramides having DL-threo- and DL-erythro-C_n-dihydrosphingosines were prepared by reactions of the bases with N-acyloxysuccinimides in tetrahydrofuran. GLC-MS analysis of O, O-di-TMS derivatives of the ceramides was carried out to find differences between threo and erythro isomers in mass spectra. One characteristic difference was observed in the relative intensity (RI) at m/e=M-103; i.e., the relative intensities of threo compounds (RI 4080%) were stronger than those of erythro isomers (RI 614%). The ratios, RI(M-103)/RI(M-15), were 3.76.8 and 0.81.3 for threo and erythro compounds, respectively. These observations demonstrate the possibility of determining erythro and threo isomers by mass spectrometry.

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The adsorption of PVAc-Allyl sulfonated copolymers (S-PVA) onto an α-Fe₂O₃ surface in an aqueous solution was investigated in regard to its capacity to prevent the deposition of α-Fe₂O₃ particles of fabrics. The coloration of PVA-I₂ complex was of use for determining S-PVA with satisfactory reproducible results. From the isotherms of adsorption of S-PVA I (not saponified) and S-PVA II (98mol% saponified) onto α-Fe₂O₃, the following results were obtained.
1) The amounts of S-PVA I and S-PVA II adsorbed onto α-Fe₂O₃ were about 60mg/α-Fe₂O₃ (g) and 20mg/α-Fe₂O₃ (g) respectively.
2) In dilute solutions, the isotherms for the adsorption of both S-PVA I and S-PVA II onto α-Fe₂O₃ should be similar to those for the Langmuir type adsorption.

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The ferrous salt FeSO₄ (NH₄) ₂SO₄·6H₂O (Mohr's salt) or calcium salt CaCl₂·2H₂O was added at various concentrations to an aqueous keratin hydrolysed solution and its fractions fractionated by membrane ultrafiltration.
The effects of added iron (II) or calcium on foam heights, foam stabilities, amounts of sediment before washing, and amount of water-insoluble precipitates were investigated. Calcium content in the water-insoluble precipitate and maximum concentration of added iron (II) which could not form a precipitate were also measured.
The foam heights and stabilities of keratin hydrolysate and its fractions increased with the addition of iron (II) or calcium.
The keratin hydrolysate and its fractions except that in the fractionated molecular weight (F.M.W.) range from 5, 000 to 10, 000 formed precipitates by the addition of calcium.
The main cause of precipitation of the fraction in the F.M.W. range from 500 to 1, 000 with the addition of calcium was found to result from the formation of insoluble calcium connected hydrolysed proteins. The precipitation of fractions in the F.M.W. range from 1, 000 to 5, 000 and above 10, 000 was due to the salting out effect or formation of soluble precipitates of hydrolyzed proteins which adsorbed calcium ions.
From measurements of ultraviolet and visible absorption spectra and change in color of metal containing hydrolysed protein solutions, the keratin hydrolysate and its fractions were shown to be connected to added iron (II) in a water-soluble chelate configulation, but not to added calcium in a soluble state in a pH range from 7.0 to 7.5, 25°C.

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The influence of cultural conditions, particularly the C/N ratio of the medium, growth temperature and nitrogen source, on the amounts of sterol and squalene formed from decane in the mycelium of two strains of Mortierella isabellina (IFO 7884, 7824) was investigated. The sterol content in the mycelium of the strains varied from 0.50.9% of the dry cell weight under cultural conditions. The greatest amounts of sterols and squalene, 15.3mg and 20.5mg/400ml medium, were observed in the strain of IFO 7824 grown at 30°C and a C/N ratio of 24.1 using NH₄NO₃ as the nitrogen source during 13 days of incubation. The influence of the cultural conditions was investigated on the qualitative and quantitative compositions of the sterols and ergosterol, ergosta-5, 7-dienol and 24-methylenedihydrolanosterol were found to be major sterols in the strains.

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Total fatty acid compositions of wild and cultured yellowtails were examined.
1) The major fatty acids in several tissues of wild and cultured yellowtails were examined and found to be C_16:0, C_18:1 (n-9), C_20:5 (n-3), and C_22:6 (n-3). In the same fish, similar fatty acid profiles were found in the dorsum, abdomen, dark tissue, and skin. But the profile in liver differed from these due to the possibly higher level of C_18:1 (n-9) and lower level of C_22:6 (n-3).
2) In yellowtails caught in March and November, no differences were observed in the fatty acid profiles in hard and soft roes of muscle tissue. However, fish caught in May had lower levels of C_14:0, C_16:1 (n-7) and C_18:1 (n-9), and higher levels of C_16:0 and C_22:6 (n-3) in the soft roe, and lower levels of C_14:0 and C_16:0 and higher levels of C_18:1 (n-9) and C_22:6 (n-3) in the hard roe than those caught in March and November.
3) In wild yellowtails, hardly any difference could be found in the fatty acid profile in adult specimens (body length : about 67cm), but were remarkable differences in the levels of C_16:0 and C_{18 :1} (n-9) in young fish (body length : about 30cm). The fatty acid profile of an adult fish differed from that of a young fish.
4) The fatty acid profiles of cultured yellowtails could be classified in two groups on the basis of C_18:1 (n-9) and C_20:5 (n-3) levels. However, no causal relation appeared to exist for the differences between fish size and rearing form or the season in the fish were caught.

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