Abstract: Oxidative stress and overwhelming free radicals
associated with diabetes mellitus are likely to be linked with
development of certain complication such as retinopathy,
nephropathy and neuropathy. Treatment of diabetic subjects with
antioxidant may be of advantage in attenuating these complications.
Olive leaf (Oleaeuropaea), has been endowed with many beneficial
and health promoting properties mostly linked to its antioxidant
activity. This study aimed to evaluate the significance of
supplementation of Olive leaves extract (OLE) in reducing oxidative
stress, hyperglycemia and hyperlipidemia in Sterptozotocin (STZ)-
induced diabetic rats. After induction of diabetes, a significant rise in
plasma glucose, lipid profiles except High density lipoproteincholestrol
(HDLc), malondialdehyde (MDA) and significant decrease
of plasma insulin, HDLc and Plasma reduced glutathione GSH as
well as alteration in enzymatic antioxidants was observed in all
diabetic animals. During treatment of diabetic rats with 0.5g/kg body
weight of Olive leaves extract (OLE) the levels of plasma (MDA)
,(GSH), insulin, lipid profiles along with blood glucose and
erythrocyte enzymatic antioxidant enzymes were significantly
restored to establish values that were not different from normal
control rats. Untreated diabetic rats on the other hand demonstrated
persistent alterations in the oxidative stress marker (MDA), blood
glucose, insulin, lipid profiles and the antioxidant parameters. These
results demonstrate that OLE may be of advantage in inhibiting
hyperglycemia, hyperlipidemia and oxidative stress induced by
diabetes and suggest that administration of OLE may be helpful in
the prevention or at least reduced of diabetic complications
associated with oxidative stress.
Abstract: The studying of enzymatic esterification of carboxylic
acids and higher alcohols was performed by esterase Saccharomyces
cerevisiae in water-organic medium. Investigation of the enzyme
specificity to acetic substrates showed the best result with acetic acid
in esterification reactions with ethanol whereas within other
carboxylic acids the esterification decreased with acids: hexanoic >
pentanoic > butyric > decanoic. In relation to higher alcohols C3-C5,
esterification increased with alcohols propanol < butanol < amylol.
Also it was determined that esterase was more specific to alcohols
with branched chain such as isobutyl alcohol and isoamyl alcohol.
Data obtained may have important practical implications, for
example, for application of yeast esterase in producing various
volatile esters as well as in enzymatic transformation of volatile acids
and toxic fusel alcohols into volatile esters by providing the
production of the high quality alcoholic beverages with redused
content of higher alcohols as well as with improved degustational and
hygienic properties.
Abstract: Nowadays there is a growing interest in biofuel production in most countries because of the increasing concerns about hydrocarbon fuel shortage and global climate changes, also for enhancing agricultural economy and producing local needs for transportation fuel. Ethanol can be produced from biomass by the hydrolysis and sugar fermentation processes. In this study ethanol was produced without using expensive commercial enzymes from sugarcane bagasse. Alkali pretreatment was used to prepare biomass before enzymatic hydrolysis. The comparison between NaOH, KOH and Ca(OH)2 shows NaOH is more effective on bagasse. The required enzymes for biomass hydrolysis were produced from sugarcane solid state fermentation via two fungi: Trichoderma longibrachiatum and Aspergillus niger. The results show that the produced enzyme solution via A. niger has functioned better than T. longibrachiatum. Ethanol was produced by simultaneous saccharification and fermentation (SSF) with crude enzyme solution from T. longibrachiatum and Saccharomyces cerevisiae yeast. To evaluate this procedure, SSF of pretreated bagasse was also done using Celluclast 1.5L by Novozymes. The yield of ethanol production by commercial enzyme and produced enzyme solution via T. longibrachiatum was 81% and 50% respectively.
Abstract: Recent research has shown that milk proteins can
yield bioactive peptides with opioid, mineral binding,
cytomodulatory, antihypertensive, immunostimulating, antimicrobial
and antioxidative activity in the human body. Bioactive peptides are
encrypted in milk proteins and are only released by enzymatic
hydrolysis in vivo during gastrointestinal digestion, food processing
or by microbial enzymes in fermented products. At present
significant research is being undertaken on the health effects of
bioactive peptides. A variety of naturally formed bioactive peptides
have been found in fermented dairy products, such as yoghurt, sour
milk and cheese. In particular, antihypertensive peptides have been
identified in fermented milks, whey and ripened cheese. Some of
these peptides have been commercialized in the form of fermented
milks. Bioactive peptides have the potential to be used in the
formulation of health-enhancing nutraceuticals, and as potent drugs
with well defined pharmacological effects.
Abstract: Pretreatment is an essential step in the conversion of
lignocellulosic biomass to fermentable sugar that used for biobutanol
production. Among pretreatment processes, microwave is considered
to improve pretreatment efficiency due to its high heating efficiency,
easy operation, and easily to combine with chemical reaction. The
main objectives of this work are to investigate the feasibility of
microwave pretreatment to enhance enzymatic hydrolysis of
corncobs and to determine the optimal conditions using response
surface methodology. Corncobs were pretreated via two-stage
pretreatment in dilute sodium hydroxide (2 %) followed by dilute
sulfuric acid 1 %. Pretreated corncobs were subjected to enzymatic
hydrolysis to produce reducing sugar. Statistical experimental design
was used to optimize pretreatment parameters including temperature,
residence time and solid-to-liquid ratio to achieve the highest amount
of glucose. The results revealed that solid-to-liquid ratio and
temperature had a significant effect on the amount of glucose.
Abstract: The present study was conducted to observe the effect
of Plantago psyllium on blood glucose and cholesterol levels in
normal and alloxan induced diabetic rats. To investigate the effect of
Plantago psyllium 40 rats were included in this study divided into
four groups of ten rats in each group. One group A was normal,
second group B was diabetic, third group C was non diabetic and
hypercholesterolemic and fourth group D was diabetic and
hypercholesterolemic. Two groups B and D were made diabetic by
intraperitonial injection of alloxan dissolved in 1mL distilled water at
a dose of 125mg/Kg of body weight. Two groups C and D were
made hypercholesterolemic by oral administration of powder
cholesterol (1g/Kg of body weight). The blood samples from all the
rats were collected from coccygial vein on 1st day, then on 21st and
42nd day respectively. All the samples were analyzed for blood
glucose and cholesterol level by using enzymatic kits. The blood
glucose and cholesterol levels of treated groups of rats showed
significant reduction after 7 weeks of treatment with Plantago
psyllium. By statistical analysis of results it was found that Plantago
psyllium has anti-diabetic and hypocholesterolemic activity in
diabetic and hypercholesterolemic albino rats.
Abstract: The worldwide prevalence of H3N2 influenza virus
and its increasing resistance to the existing drugs necessitates for the
development of an improved/better targeting anti-influenza drug.
H3N2 influenza neuraminidase is one of the two membrane-bound
proteins belonging to group-2 neuraminidases. It acts as key player
involved in viral pathogenicity and hence, is an important target of
anti-influenza drugs. Oseltamivir is one of the potent drugs targeting
this neuraminidase. In the present work, we have taken subtype N2
neuraminidase as the receptor and probable analogs of oseltamivir as
drug molecules to study the protein-drug interaction in anticipation of
finding efficient modified candidate compound. Oseltamivir analogs
were made by modifying the functional groups using Marvin Sketch
software and were docked using Schrodinger-s Glide. Oseltamivir
analog 10 was detected to have significant energy value (16% less
compared to Oseltamivir) and could be the probable lead molecule. It
infers that some of the modified compounds can interact in a novel
manner with increased hydrogen bonding at the active site of
neuraminidase and it might be better than the original drug. Further
work can be carried out such as enzymatic inhibition studies;
synthesis and crystallizing the drug-target complex to analyze the
interactions biologically.
Abstract: Dehydration process was carried out for tomato slices of var. Avinash after giving different pre-treatments such as calcium chloride (CaCl2), potassium metabisulphite (KMS), calcium chloride and potassium metabisulphite (CaCl2 +KMS), and sodium chloride (NaCl). Untreated samples served as control. Solar drier and continuous conveyor (tunnel) drier were used for dehydration. Quality characteristics of tomato slices viz. moisture content, sugar, titratable acidity, lycopene content, dehydration ratio, rehydration ratio and non-enzymatic browning as affected by dehydration process were studied. Storage study was also carried out for a period of six months for tomato powder packed into different types of packaging materials viz. metalized polyester (MP) film and low density poly ethylene (LDPE). Changes in lycopene content and non-enzymatic browning (NEB) were estimated during storage at room temperature. Pretreatment of 5 mm thickness of tomato slices with calcium chloride in combination with potassium metabisulphite and drying using a tunnel drier with subsequent storage of product in metalized polyester bags was selected as the best process.
Abstract: Enzymatic hydrolysis of starch from natural sources
finds potential application in commercial production of alcoholic
beverage and bioethanol. In this study the effect of starch
concentration, temperature, time and enzyme concentration were
studied and optimized for hydrolysis of Potato starch powder (of
mesh 80/120) into glucose syrup by immobilized (using Sodium
arginate) α-amylase using central composite design. The
experimental result on enzymatic hydrolysis of Potato starch was
subjected to multiple linear regression analysis using MINITAB 14
software. Positive linear effect of starch concentration, enzyme
concentration and time was observed on hydrolysis of Potato starch
by α-amylase. The statistical significance of the model was validated
by F-test for analysis of variance (p ≤ 0.01). The optimum value of
starch concentration, enzyme concentration, temperature, time and
were found to be 6% (w/v), 2% (w/v), 40°C and 80min respectively.
The maximum glucose yield at optimum condition was 2.34 mg/mL.
Abstract: Phytases are enzymes used as an important component
in monogastric animals feeds in order to improve phosphorous
availability, since it is not readily assimilated by these animals in the
form of the phytate presented in plants and grains. As these enzymes
are used in industrial activities, they must retain its catalytic activities
during a certain storage period. This study presents information about
the stability of 4 different phytases, produced by four macromycetes
fungi through solid-state fermentation (SSF). There is a lack of data
in literature concerning phytase from macromycetes shelf-life in
storage conditions at room, cooling and freezing temperatures. The 4
phytases from macromycetes still had enzymatic activities around
100 days of storage at room temperature. At cooling temperature in
146 days of studies, the phytase from G. stipitatum was the most
stable with 44% of the initial activity, in U.gds (units per gram of
dried fermented substrate). The freezing temperature was the best
condition storage for phytases from G. stipitatum and T. versicolor.
Each condition provided a study for each mushroom phytase,
totalizing 12 studies. The phytases showed to be stable for a long
period without the addition of additives.
Abstract: Wheat has a bimodal starch granule population and the dependency of the rate of enzymatic hydrolysis on particle size has been investigated. Ungelatinised wheaten starch granules were separated into two populations by sedimentation and decantation. Particle size was analysed by laser diffraction and morphological characteristics were viewed using SEM. The sedimentation technique though lengthy, gave satisfactory separation of the granules. Samples (10μm and original) were digested with a-amylase using a dialysis model. Granules of 10μm (p10μm. Moreover, the digestion rate was dependent on particle size whereby smaller granules produced higher rate of release. The methodology and results reported here can be used as a basis for further evaluations designed to delay the release of glucose during the digestion of native starches.
Abstract: Sol-gel immobilization of enzymes, which can improve considerably their properties, is now one of the most used techniques. By deposition of the entrapped lipase on a solid support, a new and improved biocatalyst was obtained, which can be used with excellent results in acylation reactions. In this paper, lipase B from Candida antarctica was double immobilized on different adsorbents. These biocatalysts were employed in the kinetic resolution of several aliphatic secondary alcohols in organic medium. High total recovery yields of enzymatic activity, up to 560%, were obtained. For all the studied alcohols the enantiomeric ratios E were over 200. The influence of the reaction medium was studied for the kinetic resolution of 2-pentanol.
Abstract: Tomato powder has good potential as substitute of tomato paste and other tomato products. In order to protect physicochemical properties and nutritional quality of tomato during dehydration process, investigation was carried out using different drying methods and pretreatments. Solar drier and continuous conveyor (tunnel) drier were used for dehydration where as calcium chloride (CaCl2), potassium metabisulphite (KMS), calcium chloride and potassium metabisulphite (CaCl2 +KMS), and sodium chloride (NaCl) selected for treatment.. lycopene content, dehydration ratio, rehydration ratio and non-enzymatic browning in addition to moisture, sugar and titrable acidity were studied. Results show that pre-treatment with CaCl2 and NaCl increased water removal and moisture mobility in tomato slices during drying of tomatoes. Where CaCl2 used along with KMS the NEB was recorded the least compared to other treatments and the best results were obtained while using the two chemicals in combination form. Storage studies in LDPE polymeric and metalized polyesters films showed less changes in the products packed in metallized polyester pouches and even after 6 months lycopene content did not decrease more than 20% as compared to the control sample and provide extension of shelf life in acceptable condition for 6 months. In most of the quality characteristics tunnel drier samples presented better values in comparison to solar drier.
Abstract: Mushrooms are a group of fleshy macroscopic fungi.
They have been valued throughout the world as both edible and
medicine. They are highly nutritious with good amount of quality
proteins, vitamins and minerals. An edible mushroom, Calocybe
indica was selected to validate its nutritional and medicinal
properties. Since tissue damage in hyperglycemia has been related to
oxidative stress, we evaluated the enzymatic and non-enzymatic
antioxidant status in the serum, liver and kidney since they are the
target organs in diabetic complications. From the results, increased
oxidative stress and decreased antioxidants might be related to the
causation of diabetes mellitus. The treatment in the diabetic rats with
the Calocybe indica showed an increase in the antioxidant system
and decrease in the production of free radicals. The mushrooms
which contain antioxidant phytochemicals has potential free radical
scavenging capacity and hence can induce the antioxidant system in
the body significantly reduces the generated free radicals thereby
maintaining the normal levels of the antioxidants
Abstract: Anchovy (Engraulis Encrasicholus) and sardine
(Sardina Pilchardus) are blue fishes linked to our alimentary tradition
of Mediterranean. In our work, particularly, we tested for the first
time physical and enzymatic methods to verify the freshness of
species of blue fish, anchovy and sardine of Mediterranean. In
connection with to the lowering of the pH after post-mortem stage we
assisted to a increase in proteolytic activity of calpaine and catpsine.
Already after 2 h in post-mortem there was a significant increase.
Abstract: Sugarcane Shoots is an abundantly available
residual resources consisting of lignocelluloses which take it into
the benefit. The present study was focused on utilizing of
sugarcane shoot for reducing sugar production as a substrate in
ethanol production. Physical and chemical pretreatments of
sugarcane shoot were investigated. Results showed that the size of
sugarcane shoot influenced the cellulose content. The maximum
cellulose yield (60 %) can be obtained from alkaline pretreated
sugarcane shoot with 1.0 M NaOH at 30 oC for 90 min. The
cellulose yield reached up to 93.9% (w/w). Enzymatically
hydrolyzed of cellulosic residual in 0.04 citrate buffer (pH 5) with
celluclast 1.5L (0.7 FPU/ml) resulted in the highest amount of
reducing sugar at a rate of 32.1 g/l after 4 h incubation at 50°C,
and 100 oC for 5 min . Cellulose conversion was 55.5%.
Abstract: Tomato powder has good potential as substitute of tomato paste and other tomato products. In order to protect physicochemical properties and nutritional quality of tomato during dehydration process, investigation was carried out using different drying methods and pretreatments. Solar drier and continuous conveyor (tunnel) drier were used for dehydration where as calcium chloride (CaCl2), potassium metabisulphite (KMS), calcium chloride and potassium metabisulphite (CaCl2 +KMS), and sodium chloride (NaCl) selected for treatment.. lycopene content, dehydration ratio, rehydration ratio and non-enzymatic browning in addition to moisture, sugar and titrable acidity were studied. Results show that pre-treatment with CaCl2 and NaCl increased water removal and moisture mobility in tomato slices during drying of tomatoes. Where CaCl2 used along with KMS the NEB was recorded the least compared to other treatments and the best results were obtained while using the two chemicals in combination form. Storage studies in LDPE polymeric and metalized polyesters films showed less changes in the products packed in metallized polyester pouches and even after 6 months lycopene content did not decrease more than 20% as compared to the control sample and provide extension of shelf life in acceptable condition for 6 months. In most of the quality characteristics tunnel drier samples presented better values in comparison to solar drier.
Abstract: The mathematical modeling of different biological
processes is usually used to predict or assess behavior of systems in
which these processes take place. This study deals with mathematical
and computer modeling of bi-substrate enzymatic reactions with
ping-pong mechanism, which play an important role in different
biochemical pathways. Besides that, three models of competitive
inhibition were designed using different software packages. The main
objective of this study is to represent the results from in silico
investigation of bi-substrate enzymatic reactions with ordered pingpong
mechanism in the presence of competitive inhibitors, as well as
to describe in details the inhibition effects. The simulation of the
models with certain kinetic parameters allowed investigating the
behavior of reactions as well as determined some interesting aspects
concerning influence of different cases of competitive inhibition.
Simultaneous presence of two inhibitors, competitive to the S1 and S2
substrates have been studied. Moreover, we have found the pattern of
simultaneous influence of both inhibitors.
Abstract: The present study addresses problems and solutions
related to new functional food production. Wheat (Triticum aestivum
L) bran obtained from industrial mill company “Dobeles
dzirnavieks”, was used to investigate them as raw material like
nutrients for Bifidobacterium lactis Bb-12. Enzymatic hydrolysis of
wheat bran starch was carried out by α-amylase from Bacillus
amyloliquefaciens (Sigma Aldrich). The Viscozyme L purchased
from (Sigma Aldrich) were used for reducing released sugar.
Bifidibacterium lactis Bb-12 purchased from (Probio-Tec® CHR
Hansen) was cultivated in enzymatically hydrolysed wheat bran
mash. All procedures ensured the number of active Bifidobacterium
lactis Bb-12 in the final product reached 105 CFUg-1. After enzymatic
and bacterial fermentations sample were freeze dried for analysis of
chemical compounds. All experiments were performed at Faculty of
Food Technology of Latvia University of Agriculture in January-
March 2013. The obtained results show that both types of wheat bran
(enzymatically treated and non-treated) influenced the fermentative
activity and number of Bifidibacterium lactis Bb-12 viable in wheat
bran mash. Amount of acidity strongly increase during the wheat
bran mash fermentation. The main objective of this work was to
create low-energy functional enzymatically and bacterially treated
food from wheat bran using enzymatic hydrolysis of carbohydrates
and following cultivation of Bifidobacterium lactis Bb-12.
Abstract: Agricultural residue such as oil palm fronds (OPF) is
cheap, widespread and available throughout the year. Hemicelluloses
extracted from OPF can be hydrolyzed to their monomers and used in
production of xylooligosaccharides (XOs). The objective of the
present study was to optimize the enzymatic hydrolysis process of
OPF hemicellulose by varying pH, temperature, enzyme and substrate
concentration for production of XOs. Hemicelluloses was extracted
from OPF by using 3 M potassium hydroxide (KOH) at temperature of
40°C for 4 hrs and stirred at 400 rpm. The hemicellulose was then
hydrolyzed using Trichoderma longibrachiatum xylanase at different
pH, temperature, enzyme and substrate concentration. XOs were
characterized based on reducing sugar determination. The optimum
conditions to produced XOs from OPF hemicellulose was obtained at
pH 4.6, temperature of 40°C , enzyme concentration of 2 U/mL and
2% substrate concentration. The results established the suitability of
oil palm fronds as raw material for production of XOs.