Abstract: Whey is an excellent food ingredient owing to its high nutritive value and its functional properties. However, composition of whey varies depending on composition of milk, processing conditions, processing method, and its whey protein content. The aim of this study was to prepare a whey powder from raw whey and to determine the influence of different processing temperatures (160 and 180 °C) on the physicochemical, functional properties during storage of 180 days and on whey protein denaturation. Results have shown that temperature significantly (P < 0.05) affects the pH, acidity, non-protein nitrogen (NPN), protein total soluble solids, fat and lactose contents. Significantly (p < 0.05) higher foaming capacity (FC), foam stability (FS), whey protein nitrogen index (WPNI), and a lower turbidity and solubility index (SI) were observed in whey powder processed at 160 °C compared to whey powder processed at 180 °C. During storage of 180 days, slow but progressive changes were noticed on the physicochemical and functional properties of whey powder. Reverse phase-HPLC analysis revealed a significant (P < 0.05) effect of temperature on whey protein contents. Denaturation of β-Lactoglobulin is followed by α-lacalbumin, casein glycomacropeptide (CMP/GMP), and bovine serum albumin (BSA).
Abstract: κ-casein is one of milk proteins which are very important for milk processing. Genotypes of κ-casein affect milk yield, fat, and protein content. The main factors which affect local Latvian dairy breed milk yield and composition are analyzed in research. Data were collected from 88 Latvian brown and 82 Latvian blue cows in 2015. AA genotype was 0.557 in Latvian brown and 0.232 in Latvian blue breed. BB genotype was 0.034 in Latvian brown and 0.207 in Latvian blue breed. Highest milk yield was observed in Latvian brown (5131.2 ± 172.01 kg), significantly high fat content and fat yield also was in Latvian brown (p < 0.05). Significant differences between κ-casein genotypes were not found in Latvian brown, but highest milk yield (5057 ± 130.23 kg), protein content (3.42 ± 0.03%), and protein yield (171.9 ± 4.34 kg) were with AB genotype. Significantly high fat content was observed in Latvian blue breed with BB genotype (4.29 ± 0.17%) compared with AA genotypes (3.42 ± 0.19). Similar tendency was found in protein content – 3.27 ± 0.16% with BB genotype and 2.59 ± 0.16% with AA genotype (p < 0.05). Milk yield increases by increasing parity. We did not obtain major tendency of changes of milk fat and protein content according parity.
Abstract: Rice bran is normally used as a raw material for rice
bran oil production or sold as feed with a low price. Conventionally,
the protein in defatted rice bran was extracted using alkaline
extraction and acid precipitation, which involves in chemical usage
and lowering some nutritious component. This study was conducted
in order to extract of rice bran protein concentrate (RBPC) from
defatted rice bran using enzymes and employing polysaccharides in a
precipitating step. The properties of RBPC obtained will be compared
to those of a control sample extracted using a conventional method.
The results showed that extraction of protein from rice bran using
enzymes exhibited the higher protein recovery compared to that
extraction with alkaline. The extraction conditions using alcalase 2%
(v/w) at 50 C, pH 9.5 gave the highest protein (2.44%) and yield
(32.09%) in extracted solution compared to other enzymes. Rice bran
protein concentrate powder prepared by a precipitation step using
alginate (protein in solution: alginate 1:0.016) exhibited the highest
protein (27.55%) and yield (6.84%). Precipitation using alginate was
better than that of acid. RBPC extracted with alkaline (ALK) or
enzyme alcalase (ALC), then precipitated with alginate (AL)
(samples RBP-ALK-AL and RBP-ALC-AL) yielded the precipitation
rate of 75% and 91.30%, respectively. Therefore, protein
precipitation using alginate was then selected. Amino acid profile of
control sample, and sample precipitated with alginate, as compared to
casein and soy protein isolated, showed that control sample showed
the highest content among all sample. Functional property study of
RBP showed that the highest nitrogen solubility occurred in pH 8-10.
There was no statically significant between emulsion capacity and
emulsion stability of control and sample precipitated by alginate.
However, control sample showed a higher of foaming capacity and
foaming stability compared to those of sample precipitated with
alginate. The finding was successful in terms of minimizing
chemicals used in extraction and precipitation steps in preparation of
rice bran protein concentrate. This research involves in a production
of value-added product in which the double amount of protein (28%)
compared to original amount (14%) contained in rice bran could be
beneficial in terms of adding to food products e.g. healthy drink with
high protein and fiber. In addition, the basic knowledge of functional
property of rice bran protein concentrate was obtained, which can be
used to appropriately select the application of this value-added
product from rice bran.
Abstract: Since the marine environmental conditions are
extremely different from the other ones, marine actinomycetes might
produce novel bioactive compounds. Therefore, actinomycete strains
were screened from marine water and sediment samples collected
from the coastal areas of Northern Vietnam. Ninety-nine
actinomycete strains were obtained on starch-casein agar media by
dilution technique, only seven strains, named HP112, HP12, HP411,
HPN11, HP 11, HPT13 and HPX12, showed significant antibacterial
activity against both gram-positive and gram-negative bacteria
(Bacillus subtilis ATCC 6633, Staphylococcus epidemidis ATCC
12228, Escherichia coli ATCC 11105). Further studies were carried
out with the most active HP411 strain against Candida albicans
ATCC 10231. This strain could grow rapidly on starch casein agar
and other media with high salt containing 7-10% NaCl at 28-30oC.
Spore-chain of HP411 showed an elongated and circular shape with
10 to 30 spores/chain. Identification of the strain was carried out by
employing the taxonomical studies including the 16S rRNA
sequence. Based on phylogenetic and phenotypic evidence it is
proposed that HP411 to be belongs to species Streptomyces
variabilis. The potent of the crude extract of fermentation broth of
HP411 that are effective against wide range of pathogens: both grampositive,
gram-negative and fungi. Further studies revealed that the
crude extract HP411 could obtain the anticancer activity for cancer
cell lines: Hep-G2 (liver cancer cell line); RD (cardiac and skeletal
muscle letters cell line); FL (membrane of the uterus cancer cell line).
However, the actinomycetes from marine ecosystem will be useful
for the discovery of new drugs in the future.
Abstract: Mycophenolic acid (MPA) is a secondary metabolite
produced by Penicillium brevicompactum, which has antibiotic and
immunosuppressive properties. In this study, the first, mycophenolic
acid was produced in a fermentation process by Penicillium
brevicompactum MUCL 19011 in shake flask using a base medium.
The maximum MPA production, product yield and productivity of
process were 1.379 g/L, 18.6 mg/g glucose and 4.9 mg/L. h,
respectively. Also the glucose consumption, biomass and MPA
production profiles were investigated during batch cultivation.
Obtained results showed that MPA production starts approximately
after 180 hours and reaches to a maximum at 280 h. In the next step,
the effects of some various concentrations of enzymatically
hydrolyzed casein on MPA production were evaluated. Maximum
MPA production, product yield and productivity as 3.63 g/L, 49
mg/g glucose and 12.96 mg/L.h, respectively were obtained with
using 30 g/L enzymatically hydrolyzed casein in culture medium.
These values show an enhanced MPA production, product yield and
process productivity pr as 116.8%, 132.8% and 163.2%, respectively.
Abstract: Adsorption of proteins onto a solid surface is believed to be the initial and controlling step in biofouling. A better knowledge of the fouling process can be obtained by controlling the formation of the first protein layer at a solid surface. A number of methods have been investigated to inhibit adsorption of proteins. In this study, the adsorption kinetics of
Abstract: Nonspecific protein adsorption generally occurs on
any solid surfaces and usually has adverse consequences. Adsorption
of proteins onto a solid surface is believed to be the initial and
controlling step in biofouling. Surfaces modified with end-tethered
poly(ethylene glycol) (PEG) have been shown to be protein-resistant
to some degree. In this study, the adsorption of β-casein and
lysozyme was performed on 6 different types of surfaces where PEG
was tethered onto stainless steel by polyethylene imine (PEI) through
either OH or NHS end groups. Protein adsorption was also performed
on the bare stainless steel surface as a control. The adsorption was
conducted at 23 °C and pH 7.2. In situ QCM-D was used to
determine PEG adsorption kinetics, plateau PEG chain densities,
protein adsorption kinetics and plateau protein adsorbed quantities.
PEG grafting density was the highest for a NHS coupled chain,
around 0.5 chains / nm2. Interestingly, lysozyme which has smaller
size than β-casein, appeared to adsorb much less mass than that of β-
casein. Overall, the surface with high PEG grafting density exhibited
a good protein rejection.
Abstract: The aim of the present study was to investigate the
chemical and biological properties of local cowpea seed protein
cultivated in Gizan region. The results showed that the cowpea and
its products contain high level of protein (22.9-77.6%), high
carbohydrates (9.4-64.3%) and low fats (0.1-0.3%). The trypsin and
chymotrypsin activities were found to be 32.2 and 15.2 units,
respectively. These activities were not affected in both defatted and
protein concentrate whereas they were significantly reduced in
isolated protein and cooked samples. The phytate content of cooked
and concentrated cowpea samples varied from 0.25% -0.32%,
respectively. Tannin content was found to be 0.4% and 0.23% for
cooked and raw samples, respectively. The in vitro protein
digestibility was very high in cowpea seeds (75.04-78.76%). The
biological evaluation using rats showed that the group fed with
animal feed containing casein gain more weight than those fed with
that containing cowpea. However, the group fed with cooked cowpea
gain more weight than those fed with uncooked cowpea. On the
other hand, in vivo digestion showed high value (98.33%) among the
group consumed casein compared to other groups those consumed
cowpea contains feed. This could be attributed to low antinutritional
factors in casein contains feed compared to those of cowpea contains
feed because cooking significantly increased the digestion rate
(80.8% to 83.5%) of cowpea contains feed. Furthermore, the
biological evaluation was high (91.67%) of casein containing feed
compared to that of cowpea containing feed (80.83%-87.5%). The
net protein utilization (NPU) was higher (89.67%) in the group fed
with casein containing feed than that of cowpea containing feed
(56.33%-69.67%).
Abstract: In Indonesia, goat milk is often consumed and
believed as anti-allergy. The objective of this research was to study
the effect of goat milk and their fractions (casein and whey)
supplementation on total serum IgE concentrations and leukocytes
count in rat sensitized with contact allergen dinitrochlorobenzene
(DNCB). Female Wistar rats 6-8 weeks old were divided into four
groups: 1) whey, 2) casein, 3) whole milk supplementation and 4)
phosphate-buffered saline/PBS (control). The results showed that
supplementation of goat milk on rats did not affects on total serum
IgE concentrations and number of leukocytes. After sensitized with
DNCB, the monocyte percentage in rats was higher (P
Abstract: Dispersions of casein micelles (CM) were studied at a
constant protein concentration of 5 wt % in high NaCl environment
ranging from 0% to 12% by Dynamic light scattering (DLS) and
Fourier Transform Infrared (FTIR). The rehydration profiles obtained
were interpreted in term of wetting, swelling and dispersion stages by
using a turbidity method. Two behaviours were observed depending
on the salt concentration. The first behaviour (low salt concentration)
presents a typical rehydration profile with a significant change
between 3 and 6% NaCl indicating quick wetting, swelling and long
dispersion stage. On the opposite, the dispersion stage of the second
behaviour (high salt concentration) was significantly shortened
indicating a strong modification of the protein backbone. A salt
increase result to a destabilization of the micelle and the formation of
mini-micelles more or less aggregated indicating an average micelles
size ranging from 100 to 200 nm. For the first time, the estimations
of secondary structural elements (irregular, ß-sheet, α-helix and turn)
by the Amide III assignments were correlated with results from
Amide I.
Abstract: Microparticles carrier systems made from naturally occurring polymers based on chitosan/casein system appears to be a promising carrier for the sustained release of orally and parenteral administered drugs. In the current study we followed a microencapsulation technique based aqueous coacervation method to prepare chitosan/casein microparticles of compositions 1:1, 1:2 and 1:5 incorporated with chloramphenicol. Glutaraldehyde was used as a chemical cross-linking agent. The microparticles were prepared by aerosol method and studied by optical microscopy, infrared spectroscopy, thermo gravimetric analysis, swelling studies and drug release studies at various pH. The percentage swelling of the polymers are found to be in the order pH 4 > pH 10 > pH 7 and the increase in casein composition decrease the swelling percentage. The drug release studies also follow the above order.
Abstract: The paper presents a part of the results obtained in a
complex research project on Romanian Grey Steppe breed, owner of
some remarkable qualities such as hardiness, longevity, adaptability,
special resistance to ban weather and diseases and included in the
genetic fund (G.D. no. 822/2008.) from Romania.
Following the researches effectuated, we identified alleles of six
loci, codifying the six types of major milk proteins: alpha-casein S1
(α S1-cz); beta-casein (β-cz); kappa-casein (K-cz); beta-lactoglobulin
(β-lg); alpha-lactalbumin (α-la) and alpha-casein S2 (α S2-cz). In
system αS1-cz allele αs1-Cn B has the highest frequency (0.700), in
system β-cz allele β-Cn A2 ( 0.550 ), in system K-cz allele k-CnA2 (
0.583 ) and heterozygote genotype AB ( 0.416 ) and BB (0.375), in
system β-lg allele β-lgA1 has the highest frequency (0.542 ) and
heterozygote genotype AB ( 0.500 ), in system α-la there is
monomorphism for allele α-la B and similarly in system αS2-cz for
allele αs2-Cn A.
The milk analysis by the isoelectric focalization technique (I.E.F.)
allowed the identification of a new allele for locus αS1-casein, for two
of the individuals under analysis, namely allele called αS1-casein
IRV. When experiments were repeated, we noticed that this is not a
proteolysis band and it really was a new allele that has not been
registered in the specialized literature so far. We identified two
heterozygote individuals, carriers of this allele, namely: BIRV and
CIRV. This discovery is extremely important if focus is laid on the
national genetic patrimony.
Abstract: The objective was to determine the single gene and
interaction effect of composite genotype of beta-kappa casein and
DGAT1 gene on milk yield (MY) and milk composition, content of
milk fat (%FAT), milk protein (%PRO), solid not fat (%SNF), and
total solid (%TS) in crossbred Holstein cows. Two hundred and
thirty- one cows were genotyped with PCR-RFLP for DGAT1 and
composite genotype data of beta-kappa casein from previous work
were used. Two model, (1), and (2), was used to estimate single gene
effect, and interaction effect on the traits, respectively. The
significance of interaction effects on all traits were detected. Most
traits have consistent pattern of significant when model (1), and (2)
were compared, except the effect of composite genotype of betakappa
casein on %FAT, and the effect of DGAT1 on MY, which the
significant difference was detected in only model (1).The results
suggested that when the optimum of all traits was necessary,
interaction effect should be concerned.
Abstract: The paper makes part from a complex research project
on Romanian Grey Steppe, a unique breed in terms of biological and
cultural-historical importance, on the verge of extinction and which
has been included in a preservation programme of genetic resources
from Romania. The study of genetic polymorphism of protean
fractions, especially kappa-casein, and the genotype relations of
these lactoproteins with some quantitative and qualitative features of
milk yield represents a current theme and a novelty for this breed. In
the estimation of the genetic parameters we used R.E.M.L.
(Restricted Maximum Likelihood) method.
The main lactoprotein from milk, kappa - casein (K-cz),
characterized in the specialized literature as a feature having a high
degree of hereditary transmission, behaves as such in the nucleus under
study, a value also confirmed by the heritability coefficient (h2 = 0.57
%). We must mention the medium values for milk and fat quantity
(h2=0.26, 0.29 %) and the fat and protein percentage from milk
having a high hereditary influence h2 = 0.71 - 0.63 %.
Correlations between kappa-casein and the milk quantity are
negative and strong. Between kappa-casein and other qualitative
features of milk (fat content 0.58-0.67 % and protein content 0.77-
0.87%), there are positive and very strong correlations. At the same
time, between kappa-casein and β casein (β-cz), β lactoglobulin (β-
lg) respectively, correlations are positive having high values (0.37 –
0.45 %), indicating the same causes and determining factors for the
two groups of features.