الفهرس 
Material and methodsOnly 14 pages are availabe for public view
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Abstract
This investigation included a study on the utilization
of some vegetable crops wastes,. The raw materials used
were: watermelon, carrot haulm, cauliflower leaves and
artichoke bracts.
The objectives of these studies included the following
items:-
A) The chemical composition of raw materials.
B) Preparing leaf protein concentrate (LPC).
C) Production of single cell protein (SCP) by fungal growth
(Aspergillus niger) and yeasta! growth (Saccharomyces
cerevisiae) from different substrates.
D) Production of pectin.
The obtained results could be summarized as follows:-
A) The che.tcal co.positioD of rav .at.rials iDdicatedthat:
1- Watermelon juice contained higher percentage of total
sugars (76.18%, on dry weight basis).
2- Carrot haulm and cauliflower leaves contained higher
percentage of crude protein (21.28 and 19.36%; on dry
weight basis, respectively).
3- Watermelon peels and artichoke bracts contained a
good percentage of pectin (10.13 and 6.54%, respectively,
on dry weight basis).
4- The protein content was 24.13 and 26.67%, on dry
weight basis in juices of carrot haulm and of cauliflower
leaves, respec tivel y. I t was higher in the
juices than in their cakes.
5- Albumins were the first maj or protein for juice and
dehydrated carrot haulm and cauliflower leaves [(47.82
& 47.04) and (49.69 & 41.96) for protein content,
respectively], while the globulins were the second
major protein [(19 .•06 & 18.90%) and (17.98 & 13.87%)
for protein, respectively].
According to the chemical composition of tested
vegetable wastes, carrot halum and .’ cauliflower leaves were
chosen for preparing leaf protein concentrates (LPC), while
watermelon peels and artichoke bracts were used for pectin
extraction. The watermelon juice, supernatant carrot haulm,
supernatant cauliflower leaves, hydrolyzed cake of both
carrot haulm and cauliflower to produce single cell protein
(SCP).
B) Production of leaf protein CODceatrates (LPC):
1- Different methods based on precipitation or extraction
of existent proteins of carrot haulm and cauliflower
leaves ·were eva·luated from.- th.e· point· of their
efficiency and the characteristics of the resultant
LPC. Methods based on precipitating protein from
the eIpressed juices of carrot haulm and cauliflower
leaves included various techniques such as different-
1al heat (53° & BDOC) (RP- & UNF-), polyanion1c
flocculants (FP-) and acid precipitation (AP-).
Methods based on extraction of protein from the
chopped materials of carrot haulm and cauliflower
leaves included extraction with NaOH (EM-NaOH) and
NaCI (EM-NaCI) solutions.
2- Both precipitation and extraction methods resulted
in comparable protein recovery data and differences
among each method under these two general methods
were observed. For example, in case of carrot haulm
LPC, maximum total yield (CRL-CYT) was attained using
alkali (EM-NaOH) method (81.20% for EM-NaOH vs. 73.50
and 70.091 for ml’F- and HP- methods, repectively).
In case of cauliflower leaves LPC maximum total yield
was attained also using alkali method (84.09% for
EM-NaOH vs. 78.98 and 69.89 for UNF- and HP- methods
respectively.
3- Che.ieal eo.position of LPC
The chemical composition, of all LPC, prepared by
different methods from carrot haulm and cauliflower
leaves, was respectively, as follows:
Moisture content ranged from 6.63 to 12.0%. The
highest moisture content was for CHL-LPC-FP of carrot
haulm, while the lowest moisture eontent was for
CYT-LPC-FP cauliflower leaves.
Protein content ranged from 36.15 to 53.65% and from
34.53 to 67.28%, on dry basis.
Ether ex tract content ranged from 3.85 to 8.12 and
from 1.62 to 8.93X, on dry basis.
Ash c6ntent ranged from 7.66 to 22.05% and from 6.37
to 21.18%, on dry basis.
Crude fiber content for ranged from 2.08 to 8.28%
and from 1.56 to 7.62%, on dry basis.
Total sugars content ranged from 1.01 to 9.10% and
from 3.16 to 15.98%, on dry basis.
4- Characteristicsof~:
- CHL-LPC characterized by lower total protein content
and total sugar, and higher ash, ether ex trac t and
crude fiber contents than the corresponding CYT-LPG.
- Proteins of all CHL- and CYT-LPC of. the. two sources
differed with respect to their solubilities at differen
t pH values. However, CYT-LPC seemed to be more
soluble than the CHL-LPC regardless of the source
of LPC.
- UNF-, CHL-LPC-HP and CYT-LPC-HP exhibited the lowest
solubilities at pH values 2-10 especially at pH 2
and above 7, where all other LPC showed superior
solubilities (of above 50%). However, LPC-HP had
solubilities of not less than 19.71% at pH 10 redgardless
of LPC source.
- Protein classes of LPC, in general, (regardless of
the source), UNF- and CRL-LPC proteins were character-
ized by having albumins as the first maj or protein
and having higher portion of insoluble fraction to
the corresponding CYT-LPC. On the other hand, CYTLPC
proteins were characterized by having, glutei ins
as the first major protein, and albumins as the second
and also by having low portion of insoluble protein
fraction.
- The ion-exchange chromatographic analysis revealed
the presence of 16 proteineous amino acid in LPC
of both carrot ha~lm and cauliflower leaves.
- Acidic amino acids constituted high portion of protein
in all the tested LPC t where they ranged from 26.13
to 29.21 and from 17.85 to 23.08 g/16 g N in LPC
of carrot haulm and cauliflower leaves, respectively.
The neutral amino acids comprised the second maj or
part of the total amino acids.
- CYT-LPC had the hi.ghest content in methionine than
CHL-LPC (2.32 and 1.34 g/16 g N) in CYT-LPC of carrot
haulm and cauliflower leaves, respectiYely~
The amino acid pat.tern of many of the tested LPC
was competetive with many good quality animal proteins
such as meat protein having a good level -of the
essential amino acids compared with the FAO reference
pattern.
- The obtained LPC varied greatl,. from the point of
mineral availability. Mineral elements varied in
LPC according to the source and method of extraction.
- It seems that consumption as small as about less
than 100 g of each carrot haulm and cauliflower leaves
LPC preparations would satisfy the daily recommended
allowance and in turn, req ui rements of Mg. Ca. Cu ,
Zn and” Fe.
C) SiD81e cell proteiD (SCP) productioD:
Production of SCP 1:lyusing fungal growth (Aspergillus
niger) and yeastal growth (Saccharomyces cerevisiae) on:
watermelon juice. supernatant carrot baulm. supernatant
cauliflower leaves, hydrolyzed cake of carrot haulm and
of cauliflower leaves.
1- Increasing the incubation period intreased the consumed
sugar and total yield for different substrates by using
fungi and yeast.
2- The protein content and
case of using waterDlelon
other substrates, wh4:!ther
protein yield were higher in
juice as a medium. than the
by the use of fungi or by
yeast.
3- Yield coefficient percentage was higher in case of using
fungi than using yeast for all substrates. while protein
yield was hi~her in case of using yeast than using fungi.
4- Moisture, crude protein and ash contents were lower
while ether extract lIrashigher in SCP yielded by fUDgi
than that yielded by Jeast.
5- Amino acids content was higher in SCP produced by fungi
(88.74 g/16 g N) than in that produced by yeast (72.51
g/16 g~N).
6- The first limiting amtno acid for SCP yielded by using
both fungi and yeast was methionine. The second limiting
for SCP produced by f ung d was threonine I
valine in SCP produced by yeast.
7- Nucleic acid content was higher in SCP yielded by yeast
while it was
(16.28-18.05 8/100 g protein) than in that yielded by
fungi (1.98-2.28 g/100 g protein).
8- Mineral content of Scp yielded by fungi was higher in
Mg, P, [ and Zn, whi Le the SCP yielded by yeast was
higher in Ca, Na, Fe, Mn and Cu. ”
D) Pectin production:
1- Total pectin content in watermelon peels was higher
than in the artichoke brac ts (11.47 and 7.83%, on
dry basis, respectively).
2- Pectin soluble in ammonium oxalate was the major
part of pectin in both artichoke bracts and watermelon
peels (51.85 and 55.01%, respectively).
3- The yield of pectin increased with increasing ammonium
oxalate concentrati.on and also, with inc,reasing
te.perature for both artichoke bracts and watermelon
peels.
4- The pectin extracted from watermelon peels was higher
in ash, acetyl, reducing power and AGA (anhydrous
galactourinic acid) contents, while was lower in
the methoxyl as compared with commercial pectin.
S- Physical propertielil of pectin extracted from watermelon
was nearly similar to properties of commercial
pectin.