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1.
Lipase catalyzed formation of fatty amides 总被引:2,自引:0,他引:2
Raymond G. Bistline Alexander Bilyk Stephen H. Feairheller 《Journal of the American Oil Chemists' Society》1991,68(2):95-98
Certain lipase preparations were found to facilitate the preparation of fatty amides at 20°C in hexane. Lipase preparations
investigated were from the fungiCandida rugosa, Rhizomucor miehei and porcine pancreas. Reactants were various primary alkylamines and fatty acid methyl esters or triglycerides. Moderate
yields of fatty amides were obtained using aR. miehei lipase preparation which is immobilized on a solid support as catalyst, although all three lipase preparations showed some
catalytic activity under these conditions and, in addition, showed different kinds of selectivity for fatty acid and alkylamine
chain lengths. No reaction was observed in similar experiments using one fatty acid as the substrate or one secondary amine. 相似文献
2.
Lipase-catalyzed modification of borage oil: Incorporation of capric and eicosapentaenoic acids to form structured lipids 总被引:2,自引:0,他引:2
Casimir C. Akoh Charment O. Moussata 《Journal of the American Oil Chemists' Society》1998,75(6):697-701
Two immobilized lipases, nonspecific SP435 from Candida antarctica and sn-1,3 specific IM60 from Rhizomucor miehei, were used as biocatalysts for the restructuring of borage oil (Borago officinalis L.) to incorporate capric acid (10:0, medium-chain fatty acid) and eicosapentaenoic acid (20:5n-3) with the free fatty acids
as acyl donors. Transesterification (acidolysis) reactions were carried out in hexane, and the products were analyzed by gas-liquid
chromatography. The fatty acid profiles of the modified borage oil were different from that of unmodified borage oil. Higher
incorporation of 20:5n-3 (10.2%) and 10:0 (26.3%) was obtained with IM60 lipase, compared to 8.8 and 15.5%, respectively,
with SP435 lipase. However, SP435 lipase was able to incorporate both 10:0 and 20:5n-3 fatty acids at the sn-2 position, but the IM60 lipase did not. Solvents with log P values between 3.5 and 4.5 supported the acidolysis reaction better than those with log P values between −0.33 and 3.0. 相似文献
3.
The objective of this study was to find the optimal parameters for lipase-catalyzed methanolysis of triricinolein to produce
1,2(2,3)-diricinolein. Four different immobilized lipases were tested, Candida antarctica type B (CALB), Rhizomucor miehei (RML), Pseudomonas cepacia (PCL), and Penicillium roquefortii (PRL). n-Hexane and diisopropyl ether (DIPE) were examined as reaction media at three different water activities (a
w), 0.11, 0.53, and 0.97. The consumption of triricinolein and the formation of 1,2(2,3)-diricinolein, methyl ricinoleate,
and ricinoleic acid were followed for up to 48 h. PRL gave the highest yield of 1,2(2,3)-diricinolein. Moreover, this lipase
showed the highest specificity for the studied reaction, i.e., high selectivity for the reaction with triricinolein but low
for 1,2(2,3)-diricinolein. Recoveries of 93 and 88% DAG were obtained using PRL in DIPE at a
w of 0.11 and 0.53, respectively. Further, NMR studies showed that a higher purity of the 1,2(2,3)-isomer vs. the 1,3-isomer
was achieved at higher a
w (88% at a
w=0.53), compared to lower a
w (71% at a
w=0.11). The DAG obtained was acylated by the DAG acyltransferase from Arabidopsis thaliana. Therefore, this enzymatic product is a useful enzyme substrate for lipid biosynthesis. Accordingly, the use of PRL in DIPE
at a
w 0.53 is considered optimal for the synthesis of 1,2(2,3)-diricinolein from triricinolein. 相似文献
4.
Mohamed M. Soumanou Uwe T. Bornscheuer 《European Journal of Lipid Science and Technology》2003,105(11):656-660
Fatty acid alkyl esters were produced from various vegetable oils by transesterification with different alcohols using immobilized lipases. Using n‐hexane as organic solvent, all immobilized lipases tested were found to be active during methanolysis. Highest conversion (97%) was observed with Thermomyces lanuginosa lipase after 24 h. In contrast, this lipase was almost inactive in a solvent‐free reaction medium using methanol or 2‐propanol as alcohol substrates. This could be overcome by a three‐step addition of methanol, which works efficiently for a range of vegetable oils (e.g. cottonseed, peanut, sunflower, palm olein, coconut and palm kernel) using immobilized lipases from Pseudomonas fluorescens (AK lipase) and Rhizomucor miehei (RM lipase). Repeated batch reactions showed that Rhizomucor miehei lipase was very stable over 120 h. AK and RM lipases also showed acceptable conversion levels for cottonseed oil with ethanol, 1‐propanol, 1‐butanol and isobutanol (50‐65% conversion after 24 h) in solvent‐free conditions. Methyl and isopropyl fatty acid esters obtained by enzymatic alcoholysis of natural vegetable oils can find application in biodiesel fuels and cosmetics industry, respectively. 相似文献
5.
P. Villeneuve M. Pina D. Montet J. Graille 《Journal of the American Oil Chemists' Society》1995,72(6):753-755
Short-chain fatty acids are usually located at positionsn-3 in natural triglycerides, particulary in dairy fats. As a result, it is extremely difficult to differentiate betweensn-3 stereospecificity and short-chain typoselectivity in many lipases and acyltransferases that perform in this way. This ambiguity
can be removed through successive use of a chiral triglyceride with a short fatty acid in positionsn-1 and of its racemic in controlled hydrolysis reactions. After checking that the proposed method effectively confirmed the
type of activity of control biocatalysts (Candida cylindracea nonspecific lipase andMucor miehei 1–3 regiospecific lipase), we confirmed thatCarica papaya latex has a strictsn-3 stereospecificity. 相似文献
6.
Ian C. Chandler Oliver W. Howarth David H. G. Crout 《Journal of the American Oil Chemists' Society》2001,78(9):953-958
Elucidating the stereoselectivity of lipases in synthetic reactions of triacylglycerols has hitherto been carried out using
traditional analytical techniques to determine the composition of the reaction products. These methods are laborious and are
not always appropriate for analysis of certain triacylglycerol types. A direct method, utilizing a stereospecific deuterium-labeled
triacylglycerol substrate, has been developed where the stereoisomeric composition of the reaction product is determined by
ultra-high resolution 13C nuclear magnetic resonance (NMR) spectroscopy. Through lipase-catalyzed transesterification of deuterium-labeled trilauroylglycerol
with oleic acid, chemical shifts were induced in the 13C NMR spectrum by the deuterium atom and olefinic double bonds, enabling unambiguous stereospecific assignment of triacylglycerol
species. By this method of analysis, we found an effect of the degree of reaction conversion on the extent of stereoisomerism
in the triacylglycerol product. Stereoselectivity was greatest (for sn-1) with lipase from Rhizomucor miehei. Lipases from Rhizopus niveus, Candida rugosa, Carica papaya, and the cutinase from Fusarium sp. were also found to exhibit stereoselectivity, with preference for either sn-1 or sn-3 acyl exchange. 相似文献
7.
Yoshitsugu Kosugi Qing-long Chang Kenji Kanazawa Hiroshi Nakanishi 《Journal of the American Oil Chemists' Society》1997,74(11):1395-1399
Hydrolysis specificities of lipase from Rhizomucor miehei were compared for various fatty acyl ethyl esters. Activity yields of immobilized lipases, measured with 1 mM substrate,
were more than 100%. Differences in hydrolysis rate and affinity for the substrates between lipase preparations were also
typically higher during hydrolysis of substrates at 100 mM than at 1 mM, indicating better mass transfer effects for 1-mM
substrates. The native lipase showed higher affinity for polyunsaturated fatty acid substrates at 1 mM than at 100 mM. Hydrolysis
rates for 1-mM substrates were observed with immobilized lipases, fixed on anion exchange resin with glutaraldehyde and on
cation exchange carrier with carbodiimide, and suggested some modification of the basic amino acid related to the lid of R. miehei lipase. Activation with these bifunctional reagents was not observed for 100-mM substrates, indicating that interfacial activation
always occurred because of aggregation of 100-mM substrates. These results show that lipase from R. miehei recognizes molecular aggregation of lipids, and that various changes occur in the hydrolysis specificities for fatty acids. 相似文献
8.
Effects of selected substrate forms on the synthesis of structured lipids by two immobilized lipases
Two immobilized lipases, IM 60 from Rhizomucor miehei and SP 435 from Candida antarctica, were used to synthesize structured lipids (SL). Tricaprin and trilinolein were interesterified to produce SL that contained
one linoleic acid per triacylglycerol molecule (SL1) and SL with two linoleic acids (SL2). SL1 and SL2 were separated by silver
nitrate thin-layer chromatography according to their unsaturation, and the fatty acid at the sn-2 position was determined after pancreatic lipasecatalyzed hydrolysis of SL1 and SL2. With IM 60, 57.7 mol% capric acid and
42.3 mol% linoleic acid were found at the sn-2 position of SL1, while 43.3 mol% capric acid and 56.7 mol% linoleic acid were at the sn-2 position of SL2. The fatty acid at the sn-2 position of SL1 with SP 435 as biocatalyst was 43.6 mol% capric acid and 56.4 mol% linoleic acid, while SL2 contained 56.6
mol% capric acid and 43.4 mol% linoleic acid. Different structural forms of the capric acid-containing substrate (triacylglycerol
vs. ethyl ester) and different chainlengths of triacylglycerol were selected to study the substrate selectivity of lipases.
Results indicated that SP 435 had some degree of preference for the triacylglycerol form (tricaprin), and IM 60 produced SL
more rapidly and reached steady state faster with tricaprin as substrate than with capric acid ethyl ester. For chainlength
selectivity, mol% of synthesized SL from tricaprin + trilinolein and tristearin + trilinolein were compared. SP 435 exhibited
no apparent preference for either tricaprin or tristearin. However, IM 60 showed a more rapid reaction with tricaprin than
with tristearin. 相似文献
9.
Hydroxy fatty acid (HFA) esters of long-chain alcohols, such as hydroxy stearates, have potential applications from lubricants
to cosmetics. These esters were synthesized enzymatically to overcome the problems associated with chemical processes. An
immobilized lipase, Rhizomucor miehei, was employed as catalyst in the esterification reaction between hydroxy-stearic acid as a source of HFA and monohydric fatty
alcohols (C8–C18). The yields of esters were in the range of 82–90% by conducting the reactions at 65±2°C, 2–5 mm Hg pressure, and 10% lipase
concentration. The products were analyzed by infrared spectroscopy, and some of their analytical characteristics were determined. 相似文献
10.
An immobilized sn-1,3-specific lipase from Rhizomucor miehei (IM 60) was used to catalyze the interesterification of tristearin (C18:0) and tricaprin (C10:0) to produce low-calorie structured lipids (SL). Acceptable product yields were obtained from a 1:1 mole ratio of both triacylglycerols
with 10% (w/w of reactants) of IM 60 in 3 mL hexane. The SL molecular species, based on total carbon number, were 44.2% C41 and 40.5% C49, with 3.8 and 11.5% unreacted tristearin C57 and tricaprin C27, respectively, remaining in the product mixture. The best yield of C41 species (44.3%) was obtained with zero added water. Tricaprylin (C8:0) was also successfully interesterified with tristearin in good yields at 1:1 mole ratio. Products were analyzed by reverse-phase
high-performance liquid chromatography with an evaporative light-scattering detector. Reaction parameters, such as substrate
mole ratio, enzyme load, time course, added water, reaction media, and enzyme reuse, were also investigated. Hydrolysis by
pancreatic lipase revealed the specific fatty acids present at the sn-1,3 positions of SL.
Biocatalysis Symposium Paper, presented at the AOCS Annual Meeting & Expo, Seattle, Washington. May 11–14, 1997. 相似文献
11.
Structured lipids: Lipase-catalyzed interesterification of tricaproin and trilinolein 总被引:2,自引:0,他引:2
Structured lipids were synthesized by interesterification of trilinolein and tricaproin with sn-1,3-specific (IM 60) and nonspecific (SP 435) lipases. The interesterification reaction was performed by incubating a 1:2
mole ratio of trilinolein and tricaproin in 3 mL hexane at 45°C for the IM 60 lipase from Rhizomucor miehei, and at 55°C for the SP 435 lipase from Candida antarctica. Reaction products were analyzed by reverse-phase high-performance liquid chromatography with an evaporative light-scattering
detector. The fatty acids at the sn-2 position were identified after pancreatic lipase hydrolysis and analysis with a gas chromatograph. IM 60 lipase produced
53,5 mol% dicaproyllinolein (total carbon number = C33) and 22.2% monocaproyldilinolein (C45). SP 435 lipase produced 41%
C33 and 18% C45. When caproic acid was used in place of tricaproin as the acyl donor, the IM 60 lipase produced 62.9% C33.
The effects of variation in mole ratio, temperature, added water, solvent polarity, and time course on the interesterification
reaction were also investigated. In the absence of organic solvent, IM 60 lipase produced 52.3% C33. 相似文献
12.
Weera Piyatheerawong Tsuneo Yamane Hideo Nakano Yugo Iwasaki 《Journal of the American Oil Chemists' Society》2006,83(7):603-607
Stereoselective ethanolysis of monoacid TAG by immobilized Rhizomucor miehei lipase (RML) was studied for preparation of optically pure sn-2,3-DAG. Trioctanoylglycerol (TO) was used as a model substrate. The enantiomeric purity of the product, sn-2,3-dioctanoylglycerol (sn-2,3-DO), was very high (percent enantiomeric excess >99%) when an excess of ethanol was used. The result indicated that RML
was highly stereoselective toward the sn-1 position of TO under conditions of excess ethanol. The stereoselectivity of RML depended on the amount of ethanol. The
larger the amount of ethanol was, the higher the stereoselectivity became. After optimizing the parameters such as reactant
molar ratio, water content, and temperature, (ethanol/TO molar ratio =31∶1 and water content =7.5 wt% of the reactants at
25°C), optically pure sn-2,3-DO was obtained at 61.1 mol% in the glyceride fraction in 20 min. The above conditions were further applied for ethanolysis
of monoacid TAG with different acyl groups such as tridecanoylglycerol (C10∶0), tridodecanoylglycerol (C12∶0), tritetradecanoylglycerol
(C14∶0) and trioctadecenoylglycerol [triolein, (C18∶1)]. The yields and enantiomeric purities of 1,2(2,3)-DAG were dramatically
reduced when TAG with FA longer than decanoic acid were used. 相似文献
13.
Preparation of phospholipids highly enriched with n-3 polyunsaturated fatty acids by lipase 总被引:3,自引:0,他引:3
Gudmundur G. Haraldsson Atli Thorarensen 《Journal of the American Oil Chemists' Society》1999,76(10):1143-1149
The immobilized 1,3-regiospecific Rhizomucor miehei lipase (Lipozyme™) was employed to catalyze the transesterification reaction (acidolysis) of 1,2-diacyl-sn-glycero-3-phosphatidylcholine with n-3 polyunsaturated fatty acids under nonaqueous solvent-free conditions. With a concentrate
of 55% eicosapentaenoic acid (EPA) and 30% docosahexaenoic acid (DHA) and pure phosphatidylcholine from egg yolk, phospholipids
of 32% EPA and 16% DHA content were obtained, presumably as a mixture of phosphatidylcholine and lysophosphatidylcholine.
31P nuclear magnetic resonance (NMR) analysis turned out to be a valuable technique to study the details of the reactions involved.
It revealed that when 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine was transesterified with 98% pure EPA, a substantial amount of hydrolysis side reaction took
place (39%), leading to a product mixture of 39% phosphatidylcholine, 44% lysophosphatidylcholine, and 17% sn-glycerol-3-phosphatidylcholine. The lysophosphatidylcholine constituent comprised 70% EPA, whereas the phosphatidylcholine
component contained 58% EPA. The 31P NMR technique provided valid information about the mechanism of the reaction. It became evident that a high dosage of lipase
containing 5% water afforded optimal conditions for the optimal extent of EPA incorporation into the phospholipids, under
which the extent of hydrolysis side reaction remained relatively high. 相似文献
14.
Lipase-catalyzed acidolysis of menhaden oil with a pinolenic acid (PLA) concentrate, prepared from pine nut oil, was studied
in a solvent-free system. The PLA concentrate was prepared by urea complexation of the FA obtained by saponification of pine
nut oil. Eight commercial lipases from different sources were screened for their ability to catalyze the acidolysis reaction.
Two different types of structured lipids (SL) were synthesized. The first type, which has PLA residues as a primary FA residue
at the sn-1,3 positions of the TAG, was synthesized using a 1,3-regiospecific lipase, namely, Lipozyme RM IM from Rhizomucor miehei. The second type of SL, which has PLA residues as a primary FA residue at both the sn-1,3 and sn-2 positions of the TAG, was synthesized using a nonspecific lipase, namely, Novozym 435 from Candida antarctica. The effects of variations in enzyme loading, temperature, and reaction time on PLA incorporation into the oil were monitored
by GC analyses. The optimal temperature and enzyme loading for synthesis of the two types of SL were 50°C and 10% of the total
weight of substrates for both enzymes. The optimal reaction time for the synthesis with Lipozyme RM IM was 16h, whereas the
optimal reaction time for the synthesis mediated by Novozym 435 was 36 h. Pancreatic lipase-catalyzed sn-2 positional analyses were also carried out on the TAG samples. 相似文献
15.
In-Hwan Kim Chil-Surk Yoon Soo-Hee Cho Kwang-Won Lee Soo-Hyun Chung Beom-Seok Tae 《Journal of the American Oil Chemists' Society》2001,78(5):547-551
Three commercially available immobilized lipases, Novozym 435 from Candida antarctica, Lipozyme IM from Rhizomucor miehei, and Lipase PS-C from Pseudomonas cepacia, were used as biocatalysts for the interesterification of conjugated linoleic acid (CLA) ethyl ester and tricaprylin. The
reactions were carried out in hexane, and the products were analyzed by gas-liquid chromatography. The effects of molar ratio,
enzyme load, incubation time, and temperature on CLA incorporation were investigated. Novozym 435, as compared to Lipozyme
IM and Lipase PC-C, showed the highest degree of CLA incorporation into tricaprylin. By hydrolysis with pancreatic lipase,
it was found that Lipozyme IM and Lipase PS-C exhibited high selectivity for the sn-1,3 position of the triacylglycerol early in the interesterification, with small extents of incorporation of CLA into the
sn-2 position, probably due to acyl migration, at later reaction times. A small extent of sn-1,3 selectivity during interesterification by Novozym 435 was observed. 相似文献
16.
Athina Kontogianni Vasso Skouridou Vasiliki Sereti Haralambos Stamatis Fragiskos N. Kolisis 《European Journal of Lipid Science and Technology》2001,103(10):655-660
Flavonoid fatty esters were prepared by acylation of flavonoids (rutin and naringin) by fatty acids (C8, C10, C12), catalyzed by immobilized lipase from Candida antarctica in various solvent systems. The reaction parameters affecting the conversion of the enzymatic process, such as the nature of the organic solvent and acyl donor used, the water activity (aw) of the system, as well as the acyl donor concentration have been investigated. At optimum reaction conditions, the conversion of flavonoids was 50—60% in tert‐butanol at aw less than 0.11. In all cases studied, only flavonoid monoester was identified, which indicates that this lipase‐catalyzed esterification is regioselective. 相似文献
17.
Silvia Maurelli Francesca Blasi Lina Cossignani Ancilla Bosi Maria Stella Simonetti Pietro Damiani 《Journal of the American Oil Chemists' Society》2009,86(2):127-133
The synthesis of structured triacylglycerols (TAG) by the enzymatic reaction between sn-1,3-diacylglycerols (sn-1,3-DAG) and conjugated linoleic acid (CLA) isomers was studied. Both the substrates of the reaction were produced from vegetable
oils, the sn-1,3-DAG from extra virgin olive oil and the CLA isomers from sunflower oil. The enzymatic reactions between these substrates
were catalyzed for 96 h by an immobilized lipase from Rhizomucor miehei (Lipozyme IM) and the reactions carried out in solvent were monitored every 24 h by using high-performance liquid chromatography-evaporative
light scattering detector (HPLC-ELSD). The enzymatic reactions were carried out in different reaction media (hexane, isooctane
and solvent free) and with different CLA/sn-1,3-DAG ratios. Total % acidic composition and structural analysis data were evaluated to verify the presence of CLA isomers
in sn-2- position of synthesized TAG. The results showed good levels of CLA incorporation in sn-1,3-DAG, from 19.2% of TAG synthesized in solvent free conditions with a 0.5:1 substrate ratio, to 47.5% of TAG synthesized
in isooctane with a 2:1 substrate ratio. It was observed that for all the reaction media, the best sn-2- acylic specificity was obtained with a 0.5:1 substrate ratio. 相似文献
18.
FA selectivity of lipases in acyl-transfer reactions with acetate esters of polyols in organic media
FA reaction selectivity of Burkholderia cepacia, Rhizomucor miehei, and Candida antarctica fraction B lipases was compared between acyl-transfer and esterification reactions. Multicompetitive reaction mixtures containing
a series of n-chain FA (a C4–C18 series; and a C18∶x series, where X=0-3 double bonds) and a single acetate ester co-substrate [triacetin, 1,2-propanediol (1,2-PD)diacetate,
and 1,3-PD diacetate] were studied in tert-butyl methyl ether at an a
w
of 0.69. For B. cepacia lipase, FA optima for C8, C16, and C18∶2 were observed in all reactions with 1.0- to 5.9-fold differences in FA selectivity. For R. miehei lipase, an optimum for C8 FA was observed in all reactions with 1.2- to 6.7-fold differences in FA selectivity. For C. antarctica lipase, FA optima for C8/C10 were observed in all reactions with 1.0- to 2.8-fold differences in FA selectivity. FA selectivities were broadly modulated
upon changing from free polyol to acetate ester co-substrates for B. cepacia and R miehei lipases, whereas FA selectivity modulations were more specific upon this change in reaction configuration for C. antarctica B lipase. For all lipases, reactivity toward unsaturated C18∶x FA was enhanced in acyl-transfer relative to esterification reactions with these polyol co-substrates. 相似文献
19.
Studies on the enzymatic synthesis of lipophilic derivatives of natural antioxidants 总被引:7,自引:0,他引:7
H. Stamatis V. Sereti F. N. Kolisis 《Journal of the American Oil Chemists' Society》1999,76(12):1505-1510
The esterification of some natural antioxidants such as cinnamic acid derivatives and ascorbic acid in non-aqueous media,
catalyzed by immobilized lipases from Candida antarctica and Rhizomucor miehei, was investigated. The alcohol chain length affected the rate of esterification of cinnamic acids by both lipases. Higher
reaction rates were observed when the esterification was carried out with medium- or long-chain alcohols. The rate also depended
on aromatic acid structure. The reactivity of the carboxylic function of the cinnamic acids was affected by electron-donating
substituents in the aromatic ring. Higher yields were observed for the esterification of p-hydroxyphenylacetic acid (97%) catalyzed by C. antarctica lipase and for the esterification of cinnamic acid (59%) catalyzed by R. miehei lipase. Candida antarctica lipase was more suitable for producing ascorbic acid fatty esters, catalyzing with a relatively high yield (up to 65% within
24 h) the regioselective esterification of ascorbic acid with various fatty acids in 2-methyl-2-propanol. The reaction rate
and yield depended on the fatty acid chain length and on the molar ratio of reactants. All ascorbic acid fatty esters produced
by this procedure exhibited a significant antioxidant activity in a micellar substrate composed of linoleic acid. 相似文献
20.
Esterification of polyunsaturated fatty acids by various forms of immobilized lipase from Rhizomucor miehei 总被引:1,自引:0,他引:1
Ethyl esterification specificity of a lipase from Rhizomucor miehei for polyunsaturated fatty acids (PUFA) was compared at 1 and 100 mM to study molecular recognition of PUFA. The chemical
shift of methylene adjacent to carboxyl groups in the nuclear magnetic resonance spectrum of docosahexaenoic acid (DHA) in
ethanol moved to a lower magnetic field as the concentration of DHA increased, suggesting that the degree of dissociation
of DHA decreased. Specificity constants or apparent second-order rate constants (V
max/K
m or catalytic power) for 1 mM esterification by immobilized lipases were higher than the native lipase. Immobilized hydrophobic
carrier of low mass transfer resistance for the esterification substrate may improve maximal velocity and affinity for the
substrate. Higher specificity constants for 1 mM substrates were observed using immobilized lipases fixed on an anion exchange
resin with glutaraldehyde and on a cation exchange carrier with carbodiimide. Activity yields measured with 1 mM PUFA substrate
were high. For the substrates at a concentration of 100 mM, higher specific constants with these bifunctional reagents were
not observed but higher activity yields were found. 相似文献