@article{cervantes-flores_sosinski_pecota_mwanga_catignani_truong_watkins_ulmer_yencho_2011, title={Identification of quantitative trait loci for dry-matter, starch, and beta-carotene content in sweetpotato}, volume={28}, ISSN={["1380-3743"]}, DOI={10.1007/s11032-010-9474-5}, number={2}, journal={MOLECULAR BREEDING}, publisher={Springer Nature}, author={Cervantes-Flores, J. C. and Sosinski, B. and Pecota, K. V. and Mwanga, R. O. M. and Catignani, G. L. and Truong, V. D. and Watkins, R. H. and Ulmer, M. R. and Yencho, G. C.}, year={2011}, month={Aug}, pages={201–216} }
 @article{clare_zheng_hassan_swaisgood_catignani_2008, title={Antimicrobial properties of milkfat globule membrane fractions}, volume={71}, ISSN={["1944-9097"]}, DOI={10.4315/0362-028X-71.1.126}, abstractNote={Milkfat globule membranes (MFGMs) were prepared from bovine cream according to standard procedures. These membranes and peptide hydrolysates, which were generated by proteolysis with immobilized digestive enzymes, were screened for antibacterial activity against Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica Typhimurium, Pseudomonas fluorescens, Bacillus cereus, Lactobacillus acidophilus, and Lactobacillus gasseri. Assays were first performed on beef heart infusion (BHI) plates spotted with test protein-peptide fractions and then seeded with lawns of indicator cells to monitor the zone of growth inhibition. Under these experimental conditions, MFGMs were most active against Salmonella Typhimurium and P. fluorescens. However, antibacterial activity was not seen after plating on Luria-Bertani (LB) medium. We determined that the antimicrobial effects observed on BHI plates were due to the generation of H2O2 by xanthine oxidase, a major protein constituent of the MFGMs, as a result of purine catalysis. This substrate is present in BHI but lacking in LB medium. Evaluation of purified xanthine oxidase alone resulted in analogous data trends. The growth of probiotic Lactobacillus strains were affected only marginally when grown on lactobacilli deMan Rogosa Sharpe plates, suggesting the decreased sensitivity of these bacteria to H2O2. In this study, several MFGM hydrolysates exhibited variable antibacterial activity against test food pathogens on agar plates prepared with M9 minimal media, and this variation was not attributable to xanthine oxidase enzymatic activity. The probiotic microorganisms were mostly resilient to these antibacterial fractions. Bovine MFGM fractions may represent an excellent resource material from which to generate native, naturally occurring biodefensive proteins and/or peptides.}, number={1}, journal={JOURNAL OF FOOD PROTECTION}, author={Clare, Debra A. and Zheng, Zuoxing and Hassan, Hosni M. and Swaisgood, Harold E. and Catignani, George L.}, year={2008}, month={Jan}, pages={126–133} }
 @article{willcox_ash_catignani_2004, title={Antioxidants and prevention of chronic disease}, volume={44}, DOI={10.1080/10408690490468489}, abstractNote={The generation of reactive oxygen species (ROS) and other free radicals (R•) during metabolism is a necessary and normal process that ideally is compensated for by an elaborate endogenous antioxidant system. However, due to many environmental, lifestyle, and pathological situations, excess radicals can accumulate, resulting in oxidative stress. Oxidative stress has been related to cardiovascular disease, cancer, and other chronic diseases that account for a major portion of deaths today. Antioxidants are compounds that hinder the oxidative processes and thereby delay or prevent oxidative stress. This article examines the process of oxidative stress and the pathways by which it relates to many chronic diseases. We also discuss the role that endogenous and exogenous antioxidants may play in controlling oxidation and review the evidence of their roles in preventing disease.}, number={4}, journal={CRC Critical Reviews in Food Science and Nutrition}, author={Willcox, J. K. and Ash, S. L. and Catignani, G. L.}, year={2004}, pages={275–295} }
 @article{harris_willcox_catignani_2004, title={Application of the oxidative stability index for assessing the antioxidant properties of flavonoids}, volume={28}, ISSN={["1745-4514"]}, DOI={10.1111/j.1745-4514.2004.tb00076.x}, abstractNote={The antioxidant activities of representative flavonoid classes (flavonols, flavones, flavanones, isoflavones and flavanols) relative to dl-α-tocopherol were evaluated using the Oxidative Stability Index (OSI) value. At 5 mM concentrations in tocopherol stripped corn oil (TSCO), antioxidant activity was determined as follows: (+) catechin > quercetin > (+,−) taxifolin > dl-α-tocopherol > THI (3′, 4′, 7-trihydroxyisoflavone) > luteolin. Intra-assay and inter-assay coefficients of variation were 1.43% and 2.73%. Peroxide Induction (PI) values were utilized as a comparison method using compounds and conditions identical to those in OSI experiments. Relative values for OSI and PI of the flavonoids tested showed a 0.98 correlation. This method also revealed differences in antioxidant activity of catechins due to stereochemistry. The OSI offers a simple, reproducible method for the evaluation of flavonoid antioxidant activities in a lipid environment.}, number={4}, journal={JOURNAL OF FOOD BIOCHEMISTRY}, author={Harris, GK and Willcox, JK and Catignani, GL}, year={2004}, month={Oct}, pages={337–349} }
 @article{truong_clare_catignani_swaisgood_2004, title={Cross-linking and rheological changes of whey proteins treated with microbial transglutaminase}, volume={52}, ISSN={["1520-5118"]}, DOI={10.1021/jf034397c}, abstractNote={Modification of the functionality of whey proteins using microbial transglutaminase (TGase) has been the subject of recent studies. However, changes in rheological properties of whey proteins as affected by extensive cross-linking with TGase are not well studied. The factors affecting cross-linking of whey protein isolate (WPI) using both soluble and immobilized TGase were examined, and the rheological properties of the modified proteins were characterized. The enzyme was immobilized on aminopropyl glass beads (CPG-3000) by selective adsorption of the biotinylated enzyme on avidin that had been previously immobilized. WPI (4 and 8% w/w) in deionized water, pH 7.5, containing 10 mM dithiothreitol was cross-linked using enzyme/substrate ratios of 0.12-10 units of activity/g WPI. The reaction was carried out in a jacketed bioreactor for 8 h at 40 degrees C with continuous circulation. The gel point temperature of WPI solutions treated with 0.12 unit of immobilized TGase/g was slightly decreased, but the gel strength was unaffected. However, increasing the enzyme/substrate ratio resulted in extensive cross-linking of WPI that was manifested by increases in apparent viscosity and changes in the gelation properties. For example, using 10 units of soluble TGase/g resulted in extensive cross-linking of alpha-lactalbumin and beta-lactoglobulin in WPI, as evidenced by SDS-PAGE and Western blotting results. Interestingly, the gelling point of WPI solutions increased from 68 to 94 degrees C after a 4-h reaction, and the gel strength was drastically decreased (lower storage modulus, G'). Thus, extensive intra- and interchain cross-linking probably caused formation of polymers that were too large for effective network development. These results suggest that a process could be developed to produce heat-stable whey proteins for various food applications.}, number={5}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Truong, VD and Clare, DA and Catignani, GL and Swaisgood, HE}, year={2004}, month={Mar}, pages={1170–1176} }
 @article{peet_rippy_nelson_catignani_2004, title={Organic production of greenhouse tomatoes utilizing the bag system and soluble organic fertilizers}, volume={659}, ISBN={["90-6605-259-7"]}, ISSN={["0567-7572"]}, DOI={10.17660/actahortic.2004.659.92}, abstractNote={ISHS VII International Symposium on Protected Cultivation in Mild Winter Climates: Production, Pest Management and Global Competition ORGANIC PRODUCTION OF GREENHOUSE TOMATOES UTILIZING THE BAG SYSTEM AND SOLUBLE ORGANIC FERTILIZERS}, number={659}, journal={PROCEEDINGS OF THE VIITH INTERNATIONAL SYMPOSIUM ON PROTECTED CULTIVATION IN MILD WINTER CLIMATES: PRODUCTION, PEST MANAGEMENT AND GLOBAL COMPETITION, VOLS 1 AND 2}, author={Peet, MM and Rippy, JM and Nelson, PV and Catignani, GL}, year={2004}, pages={707–719} }
 @misc{clare_catignani_swaisgood_2003, title={Biodefense properties of milk: The role of antimicrobial proteins and peptides}, volume={9}, ISSN={["1873-4286"]}, DOI={10.2174/1381612033454874}, abstractNote={Mammary fluids, colostrum and milk, deliver nature's first host defense systems upon birth, and these essential liquids are critical for survival of the neonate. The identification and characterization of anti-infectious proteins were among the early scientific discoveries and this group of proteins has long been recognized for promoting health benefits in both newborns and adults. Among the more widely studied are the immunoglobulins, lactoperoxidase, lysozyme, and lactoferrin. Recently, it was shown that alpha--lactalbumin may also function in a protective capacity dependent upon its folding state. Some of these, especially lactoferrin, also display an immunomodulatory role in which case a totally separate cascade of host defense responses is initiated. It was noted that the mechanism of action for this cluster of sentry proteins does vary; thus, this protective strategy provides for a broad range of responsive reactions to infection. Presently, there is a major focus on the discovery of novel peptides that can be generated from existing milk proteins via proteolytic reactions. To date, this substrate list includes alpha--lactalbumin, beta-lactoglobulin, all casein fractions, and lactoferrin. Again, the immunoregulatory effects prompted as a result of the appearance of these peptides are currently being defined. Herein, we review the principal biological properties associated with each of these contributing milk components with a special emphasis on the role of biodefensive milk peptides. We envision future contributions emerging from this research field as an opportunity to develop effective new therapies to be used in treating infectious diseases and promoting health benefits in vivo.}, number={16}, journal={CURRENT PHARMACEUTICAL DESIGN}, author={Clare, DA and Catignani, GL and Swaisgood, HE}, year={2003}, pages={1239–1255} }
 @article{willcox_catignani_roberts_2003, title={Dietary flavonoids fail to suppress F-2-isoprostane formation in vivo}, volume={34}, ISSN={["1873-4596"]}, DOI={10.1016/S0891-5849(02)01425-9}, abstractNote={Dietary antioxidants, including α-tocopherol (α-TOH) and polyphenolic flavonoid compounds, have been the subject of much research interest, but few studies have investigated interactions between these two antioxidants in vivo. We have conducted a feeding study to determine if supplementation with dietary flavonoids or polyphenol-containing compounds will provide antioxidant protection in tocopherol-deficient animals or exceed the antioxidant protection provided by α-TOH alone, using the sensitive and specific measure of lipid peroxidation, F2-isoprostanes. Seventy-two male Sprague Dawley rats were divided into 12 treatment groups to receive either α-TOH-sufficient or -deficient AIN93-G diet supplemented with one of five compounds: 0.5% quercetin, catechin, or epicatechin; or 1% cocoa powder or lignin. The fat source was polyunsaturated oil, increased from 7 to 11.05% (w/w with diet) to maximize lipid peroxidation while staying within a physiological range. After 7 weeks of treatment, animals were sacrificed with plasma and hearts analyzed to determine differences in F2-isoprostane levels. None of the treatment compounds significantly decreased plasma or heart F2-isoprostanes compared to the control beyond the significant protection displayed by α-tocopherol. We conclude that under these experimental conditions, quercetin, catechin, and epicatechin do not suppress lipid peroxidation in vivo.}, number={7}, journal={FREE RADICAL BIOLOGY AND MEDICINE}, author={Willcox, JK and Catignani, GL and Roberts, LJ}, year={2003}, month={Apr}, pages={795–799} }
 @misc{willcox_catignani_lazarus_2003, title={Tomatoes and cardiovascular health}, volume={43}, ISSN={["1549-7852"]}, DOI={10.1080/10408690390826437}, abstractNote={Diet is believed to play a complex role in the development of cardiovascular disease, the leading cause of death in the Western world. Tomatoes, the second most produced and consumed vegetable nationwide, are a rich source of lycopene, beta-carotene, folate, potassium, vitamin C, flavonoids, and vitamin E. The processing of tomatoes may significantly affect the bioavailability of these nutrients. Homogenization, heat treatment, and the incorporation of oil in processed tomato products leads to increased lycopene bioavailability, while some of the same processes cause significant loss of other nutrients. Nutrient content is also affected by variety and maturity. Many of these nutrients may function individually, or in concert, to protect lipoproteins and vascular cells from oxidation, the most widely accepted theory for the genesis of atherosclerosis. This hypothesis has been supported by in vitro, limited in vivo, and many epidemiological studies that associate reduced cardiovascular risk with consumption of antioxidant-rich foods. Other cardioprotective functions provided by the nutrients in tomatoes may include the reduction of low-density lipoprotein (LDL) cholesterol, homocysteine, platelet aggregation, and blood pressure. Because tomatoes include several nutrients associated with theoretical or proven effects and are widely consumed year round, they may be considered a valuable component of a cardioprotective diet. Referee: Dr. John Erdman, Director, Division of Nutrition and Food Science, University of Illinois, 455 Bevier Hall, 905 South Goodwin, Urbana, IL 61801}, number={1}, journal={CRITICAL REVIEWS IN FOOD SCIENCE AND NUTRITION}, author={Willcox, JK and Catignani, GL and Lazarus, S}, year={2003}, pages={1–18} }
 @article{zhao_clare_catignani_swaisgood_2002, title={Purification and characterization of the fusion protein trypsin-streptavidin expressed in Escherichia coli}, volume={21}, ISSN={["0277-8033"]}, DOI={10.1023/A:1021134617137}, number={6}, journal={JOURNAL OF PROTEIN CHEMISTRY}, author={Zhao, F and Clare, DA and Catignani, GL and Swaisgood, HE}, year={2002}, month={Aug}, pages={413–418} }
 @article{clare_valentine_catignani_swaisgood_2001, title={Molecular design, expression, and affinity immobilization of a trypsin-streptavidin fusion protein}, volume={28}, ISSN={["1879-0909"]}, DOI={10.1016/S0141-0229(00)00361-6}, abstractNote={A trypsin-streptavidin (TRYPSA) fusion protein was designed and its expression in Escherichia coli was evaluated. The streptavidin gene was PCR modified and cloned into the pET expression vector. The trypsin gene was subsequently inserted into this plasmid, thus generating a colinear fusion of trypsin and streptavidin genes (pTRYPSA). This engineering strategy was verified, and TRYPSA was expressed after IPTG induction using the E. coli strains, BL21(DE3) and BL21(DE3)pLysS. Standard protein fractions of the cell lysate were prepared and trypsin activity was primarily detected in the periplasmic and inclusion body fractions. Immunoblotting showed a single Western-positive band exhibiting a molecular weight of 39,000 Da. A biotinylated porous glass affinity matrix was prepared and selective adsorption resulted in a one-step purification and immobilization of TRYPSA from crude cell lysate. Trypsin activity was verified using a synthetic substrate. This enzyme bioreactor should serve as an excellent prototype for future studies that will examine the effect of limited proteolysis on functional characteristics of milk proteins, including gelling, emulsifying and foaming properties.}, number={6}, journal={ENZYME AND MICROBIAL TECHNOLOGY}, author={Clare, DA and Valentine, VW and Catignani, GL and Swaisgood, HE}, year={2001}, month={Apr}, pages={483–491} }
 @article{henry_puspitasari-nienaber_jaren-galan_breemen_catignani_schwartz_2000, title={Effects of ozone and oxygen on the degradation of carotenoids in an aqueous model system}, volume={48}, ISSN={["0021-8561"]}, DOI={10.1021/jf000503o}, abstractNote={The effects of ozone and oxygen on the degradation of carotenoids in an aqueous model system were studied. All-trans beta-carotene, 9-cis beta-carotene, beta-cryptoxanthin, and lycopene were adsorbed onto a C(18) solid phase and exposed to a continuous flow of water saturated with oxygen or ozone at 30 degrees C. Carotenoids were analyzed using HPLC with a C(30) column and a photodiode array detector. Approximately 90% of all-trans beta-carotene, 9-cis beta-carotene, and beta-cryptoxanthin were lost after exposure to ozone for 7 h. A similar loss of lycopene occurred in only 1 h. When exposed to oxygen, all carotenoids, except beta-cryptoxanthin, degraded at lower rates. The degradation of all the carotenoids followed zero-order reaction kinetics with the following relative rates: lycopene > beta-cryptoxanthin > all-trans beta-carotene > 9-cis beta-carotene. The major degradation products of beta-carotene were tentatively identified on the basis of their elution on the HPLC column, UV-Vis spectra, and electrospray LC-MS. Predominant isomers of beta-carotene were 13-cis, 9-cis, and a di-cis isomer. Products resulting from cleavage of the molecule were beta-apo-13-carotenone and beta-apo-14'-carotenal, whereas epoxidation yielded beta-carotene 5,8-epoxide and beta-carotene 5, 8-endoperoxide.}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Henry, LK and Puspitasari-Nienaber, NL and Jaren-Galan, M and Breemen, RB and Catignani, GL and Schwartz, SJ}, year={2000}, month={Oct}, pages={5008–5013} }
 @article{huang_catignani_swaisgood_1999, title={Modification of rheological properties of whey protein isolates by limited proteolysis}, volume={43}, ISSN={["0027-769X"]}, DOI={10.1002/(SICI)1521-3803(19990301)43:2<79::AID-FOOD79>3.0.CO;2-8}, abstractNote={Whey protein isolate (WPI) was subjected to limited tryptic hydrolysis and the effect of the limited hydrolysis on the rheological properties of WPI was examined and compared with those of untreated WPI. At 10% concentration (w/v in 50 mM TES buffer, pH 7.0, containing 50 mM NaCI), both WPI and the enzyme-treated WPI (EWPI) formed heat-induced viscoelastic gels. However, EWPI formed weaker gels (lower storage modulus) than WPI gels. Moreover, a lower gelation point (77 °C) was obtained for EWPI as compared with that of WPI which gelled at 80 °C only after holding 1.4 min. Thermal analysis and aggregation studies indicated that limited proteolysis resulted in changes in the denaturation and aggregation properties. As a consequenece, EWPI formed particulated gels, while WPI formed fine-stranded gels. In keeping with the formation ofa particulate gel, Texture Profile Analysis (TPA) ofthe heat-induced gels (at 80 °C for 30 min) revealed that EWPI gels possessed significantly higher (p < 0.05) cohesiveness, hardness, gumminess, and chewiness but did not fracture at 75% deformation. The results suggest that the domain peptides, especially β-lactoglobulin domains released by the limited proteolysis, were responsible for the altered gelation properties.}, number={2}, journal={NAHRUNG-FOOD}, author={Huang, XL and Catignani, GL and Swaisgood, HE}, year={1999}, month={Apr}, pages={79–85} }
 @article{henry_catignani_schwartz_1998, title={Oxidative degradation kinetics of lycopene, lutein, and 9-cis and all-trans beta-carotenee}, volume={75}, ISSN={["0003-021X"]}, DOI={10.1007/s11746-998-0232-3}, abstractNote={Abstract The thermal and oxidative degradation of carotenoids was studied in an oil model system to determine their relative stabilities and the major β‐carotene isomers formed during the reaction. All‐ trans β‐carotene, 9‐ cis β‐carotene, lycopene, and lutein were heated in safflower seed oil at 75, 85, and 95°C for 24, 12, and 5 h, respectively. The major isomers formed during heating of β‐carotene were 13‐ cis , 9‐ cis , and an unidentified cis isomer. The degradation kinetics for the carotenoids followed a first‐order kinetic model. The rates of degradation were as follows: lycopene>all‐ trans β‐carotene≈9‐ cis β‐carotene>lutein. The values for the thermodynamic parameters indicate that a kinetic compensation effect exists between all of the carotenoids. These data suggest that lycopene was most susceptible to degradation and lutein had the greatest stability in the model system of the carotenoids tested. Furthermore, there was no significant difference in the rates of degradation for 9‐ cis and all‐ trans β‐carotene under the experimental conditions.}, number={7}, journal={JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY}, author={Henry, LK and Catignani, G and Schwartz, S}, year={1998}, month={Jul}, pages={823–829} }
 @article{henry_catignani_schwartz_1998, title={The influence of carotenoids and tocopherols on the stability of safflower seed oil during heat-catalyzed oxidation}, volume={75}, ISSN={["0003-021X"]}, DOI={10.1007/s11746-998-0189-2}, abstractNote={Abstract The stability and antioxidant effects of carotenoids and tocopherols in safflower seed oil were evaluated under thermal (75°C) and oxidative conditions and the oxidative stability index (OSI) determined. The antioxidant capability of butylated hydroxytoluene (BHT) was also compared with that of β‐carotene in a model system. Lycopene and β‐carotene (1 to 2000 ppm) were heated (75°C) and exposed to air (2.5 psi) in an oxidative stability instrument. β‐Carotene had no antioxidant effect at concentrations below 500 ppm, because it did not alter the induction time. Lycopene increased the induction time only slightly at low concentrations. However, at concentrations greater than 500 ppm, both β‐carotene and lycopene acted as prooxidants, significantly decreasing the induction period. At the highest concentration, 2000 ppm, lycopene was more prooxidative than β‐carotene. α‐ and γ‐Tocopherol (concentration, 1000 ppm) delayed the induction time by 16 and 26 h, respectively. There was no cooperative interaction between α‐tocopherol and β‐carotene in delaying the onset of oxidation. Furthermore, BHT was significantly more antioxidative than β‐carotene. Thus, under thermal and oxidative conditions, β‐carotene could not delay the onset of oxidation. The tocopherols and BHT were effective in suppressing the onset of oxidation, as determined by the oxidative stability measurement.}, number={10}, journal={JOURNAL OF THE AMERICAN OIL CHEMISTS SOCIETY}, author={Henry, LK and Catignani, GL and Schwartz, SJ}, year={1998}, month={Oct}, pages={1399–1402} }
 @article{huang_catignani_swaisgood_1997, title={Comparison of the properties of trypsin immobilized on 2 Celite(TM) derivatives}, volume={53}, ISSN={["0168-1656"]}, DOI={10.1016/S0168-1656(96)01656-2}, abstractNote={Trypsin was immobilized on 2 Celite derivatives and the kinetic properties of trypsin immobilized on these derivatives were determined and compared. Celite was derivatized with organosilane to give aminopropyl-Celite (APC) and a portion of this derivative was then succinylated to give succinamidopropyl-Celite (SAPC). Trypsin was covalently immobilized on APC using glutaraldehyde to activate amino groups and on SAPC using water-soluble carbodiimide to activate surface carboxyl groups. Enzyme loadings were 13.9 and 17.8 mg ml-1 of beads on APC and SAPC, respectively. Using p-tosyl-L-arginine methyl ester as substrate, the catalyst specific activity, KMapp and kcat/KMapp were 17.8 U ml-1 of beads, 3.60 and 21.0 mM-1 min-1, respectively, for trypsin-APC as compared with 24.5 U ml-1 of beads, 3.77 and 20.3 mM-1 min-1, respectively, for trypsin-SAPC. With beta-lactoglobulin as substrate, KMapp and kcat/KMapp were 0.36 and 1.62 mM-1 min-1 for trypsin-APC and 0.54 and 1.39 mM-1 min-1 for trypsin-SAPC, respectively. The pH range for optimal activity was much larger for both immobilized forms as compared with the soluble enzyme. The optimal temperature ranges were 40-50 degrees C for trypsin-APC and 50-60 degrees C for trypsin-SAPC. The two methods of immobilization on Celite gave biocataysts with similar kinetic properties but immobilization on SAPC yielded slightly higher loadings and higher specific activities.}, number={1}, journal={JOURNAL OF BIOTECHNOLOGY}, author={Huang, XL and Catignani, GL and Swaisgood, HE}, year={1997}, month={Feb}, pages={21–27} }
 @article{huang_catignani_swaisgood_1997, title={Micro-scale method for determining foaming properties of protein}, volume={62}, ISSN={["0022-1147"]}, DOI={10.1111/j.1365-2621.1997.tb15030.x}, abstractNote={A 5% protein suspension (4 mL) was whipped in a modified 50-mL centrifuge tube using a tissumizer equipped with a flat-bottom generator. Drainage time at 50% liquid weight and the weight of the foam formed/ unit volume were used for calculating foam stability and foam overrun, respectively. The foaming properties of a variety of milk proteins were determined using this method. This method distinguished differences in foaming properties among the proteins. Values for overrun confirmed published results. Compared with standard methods, this method required much less sample (about 1/20) and less measuring time (about 1/5 to 1/10).}, number={5}, journal={JOURNAL OF FOOD SCIENCE}, author={Huang, XL and Catignani, GL and Swaisgood, HE}, year={1997}, pages={1028-&} }
 @article{lessin_catigani_schwartz_1997, title={Quantification of cis-trans isomers of provitamin A carotenoids in fresh and processed fruits and vegetables}, volume={45}, ISSN={["0021-8561"]}, DOI={10.1021/jf960803z}, abstractNote={A polymeric 5 μm C30 stationary phase for reversed phase HPLC was used to separate and quantitate geometric isomers of provitamin A carotenoids in fresh and processed fruits and vegetables. β-Carotene isomers (all-trans, 9-cis, 13-cis, and 15-cis), α-carotene isomers (all-trans, 9-cis, 13-cis, and 13‘-cis), and β-cryptoxanthin isomers (all-trans, 13 and 13‘-cis, and 15-cis) were resolved isocratically using the C30 stationary phase with 89:11 methanol/methyl tert-butyl ether as mobile phase. The percent of cis isomers increased 10−39% with canning. The total provitamin A carotenoid content (in micrograms per gram of dry weight of tissue) ranged from 3.5 to 907 in fresh samples and from 1.8 to 1055 in canned samples. In several fruits and vegetables, processing produced an increase of 16−50% of total measured provitamin A carotenoids relative to the fresh samples. These increases were most likely a result of increased extraction efficiency, inactivation of enzymes capable of degrading carotenoids, and/or l...}, number={10}, journal={JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY}, author={Lessin, WJ and Catigani, GL and Schwartz, SJ}, year={1997}, month={Oct}, pages={3728–3732} }
 @article{church_swaisgood_porter_catignani_1983, title={SPECTROPHOTOMETRIC ASSAY USING ORTHO-PHTHALDIALDEHYDE FOR DETERMINATION OF PROTEOLYSIS IN MILK AND ISOLATED MILK-PROTEINS}, volume={66}, ISSN={["0022-0302"]}, DOI={10.3168/jds.S0022-0302(83)81926-2}, abstractNote={Abstract A rapid, sensitive, and convenient Spectrophotometric assay was developed and characterized for measurement of proteolysis of milk proteins in buffered solutions or in milk. α -Amino groups released by hydrolysis react with ο -phthaldialdehyde and ( β -mercaptoethanol to form an adduct that absorbs strongly at 340nm. The absorptivity ( ɛ = 6000M −1 cm −1 ) is similar for all α -amino groups. Moreover, the absorptivity of the adduct with both α - and ɛ -amino groups of proteins is also similar and unaffected by local environment when proteins are denatured in sodium dodecyl sulfate. Thus, background is constant for a particular sample, and α -amino groups released by proteolysis can be quantitated accurately. Inclusion of sodium dodecyl sulfate in the assay provides a convenient way to terminate proteolysis and to insure full exposure and complete reaction of amino groups. Because all hydrolytic products are assayed, the method is more accurate than procedures that depend upon properties of aromatic residues (Hull and Lowry methods). Furthermore, the o-phthaldialdehyde Spectrophotometric assay is more rapid and convenient than methods using ninhydrin, 2,4,6-trinitrobenzenesulfonic acid, or fluorescamine. The assay proved to be especially useful for measuring proteolysis in milk from microbial culture organisms such as Streptococcus lactis C2. Because trichloroacetic acid filtrates are used, the method should be adaptable to other dairy products.}, number={6}, journal={JOURNAL OF DAIRY SCIENCE}, author={CHURCH, FC and SWAISGOOD, HE and PORTER, DH and CATIGNANI, GL}, year={1983}, pages={1219–1227} }
 @article{catignani_bieri_1983, title={Simultaneous determination of retinol and alpha-tocopherol in serum or plasma by liquid-chromatography}, volume={29}, number={4}, journal={Clinical Chemistry}, author={Catignani, G. L. and Bieri, J. G.}, year={1983}, pages={708–712} }