Review: Impact of Starch Nanoparticles on Native Starch Properties

This report provides a comprehensive review of the impact of starch nanoparticles on the properties of native starch. It begins with an introduction to starch, its composition (amylose and amylopectin), and its various sources, highlighting the importance of starch in food and industrial applications. The report then delves into the concept of starch modification, explaining the difference between native and modified starch and the various methods used for modification, including physical, chemical, and enzymatic treatments. The core of the report focuses on how the synthesis of starch nanoparticles affects properties such as amylose content, pasting, rheological behavior, morphology, and particle size distribution. It also examines the effects of different synthesis methods, such as acid hydrolysis, on these properties. The report emphasizes that the synthesis of starch nanoparticles can alter the structure of starch, influencing its functional properties and making it suitable for various applications in food and non-food industries. The study also mentions the use of starch nanoparticles in nano-emulsions, nano starch-based composite movies, and drug transport systems, providing a detailed overview of the current research and potential future directions for utilizing starch nanoparticles.

Impact on various properties of native starch after synthesis of starch nanoparticles: A
review
Abstract
In recent years, interdisciplinary research is more focused on particle size, which helps in
exploring the relation between micro and macroscopic properties of various materials.
Researchers are showing interest in the starch nanoparticles synthesis to increase its
applications. Starch nanoparticles are generally synthesized by using acid/enzymatic
hydrolysis, gamma irradiation, simple nanoprecipitation, ultra-sonication, and
homogenization treatments. The properties like amylose content, pasting, rheological,
morphological, size distribution, etc. are affected after the formation starch nanoparticles
development form native starch. In this review impact on various starch properties after the
preparation of starch nanoparticles are described. This study emphasizes how various
properties (i.e physicochemical, functional, morphological, etc.) are affected after the starch
nanoparticles production so that they can be utilized in appropriate food as well as non-food
applications. Traditionally, studies have focused on the synthesis and of starch nanoparticles
description. Starch nanoparticles are used within the system of nano-emulsion, nano starch-
based composite movies, and in drug transport. The effect on diverse native starch properties
after practise of starch nanoparticles are much less said. So, all the elements related to
numerous starch homes and its nanoparticles are appreciably reviewed on this look at in order
that the listed findings can be utilized in destiny tactics to increase the various meals and
different utilization of starch nanoparticles.
Keywords: Starch Nanoparticle, amylose content, rheological properties, particles size,
morphology, biocompatibility.
Introduction
Starch can be referred to as the polymer that is manufactured in plants from the excess
glucose that is produced during the process of photosynthesis. It is a major part of the
human diet and is found in various foods such as pasta, bread, potato, rice, etc. It is non-toxic,
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non- allergenic, abundant, cheap, and generally recognized as safe (Zhao et al., 2018). It can
be considered as a source of energy and used in food as well as in different industrial
applications. Starch is made up of two components, namely amylopectin and amylose
(Hanani, 2018). The ratio of amylose/amylopectin is responsible for various functional
properties such as solubility, viscosity, gel stability, shear resistance, gelatinization, and
retrogradation, etc (Klaochanpong, Puttanlek, Rungsardthong, Puncha-arnon, & Uttapap,
2015). Starch from different botanical sources shows the variation in their properties such as
physicochemical, functional, morphological, thermal, rheological, etc. (Thory & Sandhu,
2017; Dularia, Sinhmar, Thory, Pathera, & Nain, 2019; Roy, Thory, Sinhmar, Pathera, &
Nain, 2020). Starch is generally divided into four major categories: cereal, tuber, legume,
and other starches. Now the day, starches extracted from different genotypes/botanical
sources are receiving more attention, moreover sometimes physical and chemical
modification of starches makes them suitable for specific applications (Man, Cai, Cai,
Huai, & Wei, 2012). In foodstuffs, starch can influence different characteristics like
moisture, aesthetic, consistency as well as shelf stability. (Kamenan, Rolland-Sabate, &
Colonna, 2005). Commonly, starches are used in soup, gravy, stew, filling of a pie, in making
custard and sauces. It helps in improving the texture of the food and act as a thickener or bulking agent.
Apart from this, it also acts as an adhesive and gelling agent etc. (Hadimani, Muralikrishna,
Tharanathan, & Malleshi, 2001). When the starch is extracted directly from the plant, it is
known as “native starch” and when it goes through physical, chemical, and enzymatic
treatment, native starch results in enhancement of various properties and generally known as
“modified starch”. Domestically produced starch has certain limitations when it comes to its
application at an industrial level. This is because the granules of the starch easily hydrate,
swells and ruptures quickly as well as loses its viscosity. It also produces paste that is
cohesive (Kamenan et. al., 2005). To overcome these limitations modification of starches
is required. T h e m o d i f i c a t i o n o f s t a r c h a l t e r s i t s s t r u c t u r e b y i m p a c t i n g
t h e h y d r o g e n b o n d i n a c o n t r o l l e d m a n n e r (Yiu, Loh, Rajan, Wong, & Bong,
2008). If the alteration is done physically, it involves modifying the properties of starch in a
controlled way through heat and moisture. This results in the modification of the properties of
starch granules. This includes the granules with a high amylose content, surfaces that were
less smooth as well as less swelling and surfaces. Apart from this, it also includes less
solubility index and an increased level of water absorption capacity (Goel, Semwal, Khan,
Kumar, & Sharma, 2020).
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On the other hand, modification can also be carried out chemically by introducing a
functional group in the molecule of starch in its original form. This helps in bringing out
changes in the properties of the starch molecule. Chemical modification produces reflective
modification in the composition of the molecule as well as pasting characteristics along with
retrogradation of domestically produced granules of starch. In chemical modifications, such
as in acid modification of starch, the granular modification of the native starch takes place
by treating starch below its gel point in aqueous acid suspension, hydrolysis reduces the size
of the granule as well as paste viscosity. Also, the amylopectin depolymerisation is increased
along with the quantity of linear chains that are similar to amylose as they favour the
formation and strength of the gel (Wang & Wang, 2001; Ulbrich, Natan, & Floter, 2014).
Modifications within the enzymes involve exposing the starch to various enzymes including
hydrolysing enzymes that mainly tend to produce derivatives that are highly functional. This
includes different enzymes that occur in plants like iso-amylase and pullulanase groups.
Pullulanase can said to be a glucosidase having 6-α molecules. This impacts the linear alpha-
glucan statistically and releases maltotriose oligomers. Not only this, it also hydrolyses α 1,
6-glycoside bond in amylopectin and dextrines whereas their side-chains include at least two
α-1, 4-glycoside bonds. Isoamylase is another enzyme that completely hydrolyses α-1, 6-
glycoside bonds in amylopectin, glycogen, and some branched maltodextrins and
oligosaccharides, but is characterized by low activity in relation to pullulan (Norman,1981).
Now the day, interdisciplinary research is more focused on particle size, which helps in
understanding the relation between micro as well as macroscopic properties of the different materials. The
word “nano” means a size of 10-9m while, nanotechnology refers to fabrication and
manipulation of specific material having a size less than 100 nm. The size as well as
shape of the granules can affect its various properties such as texture, taste, appearance as
well as functionality (Dera & Teseme, 2020). On the basis of their nature, nanoparticles are
grouped into different categories such as inorganic (silver, gold, zinc oxide, a carbon-based
material, etc.), organic (polysaccharides, lipids, proteins, etc.) and combined
organic/inorganic or surface-modified nanoparticles (Bouwmeester, Brandhoff, Marvin,
Weigel, & Peters, 2014). The attention of nanoparticles extensively impacts the
physicochemical residences (density, rheology, polarity, refractive index), particle
houses (charge, size), shielding properties (antioxidant homes), encapsulation
(loading capability, encapsulation conduct, and retention efficiencies) and launch
houses (cause fee and quantity). Nano starch basically has some uncommon
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chemical properties and is taken into consideration as a singular cloth. (Wilson,
Stanley, Eyles, & Ross, 2019). They generally have a small size and a large surface area
(Mujtaba et al., 2019). S t a r c h n a n o p a r t i c l e s a r e t y p i c a l l y e v o l v e d
t h r o u g h a c i d h y d r o l y s i s p r o c e d u r e , t h r u t h e u t i l i z a t i o n o f
a m y l o p e c t i n f r o m s t a r c h ( G r a n d e - T o v a r e t a l . , 2 0 1 8 ) . T h e a c i d
h y d r o l y s i s m e t h o d a l t e r s t h e s t r u c t u r e o f s t a r c h f r o m p o l y m e r t o
m o n o m e r a n d f u r t h e r y i e l d s t a r c h n a n o c r y s t a l (Patel & Panigrahi, 2019).
During the acid hydrolysis process, the amorphous area of the starch is eliminated and
destroyed (Lambert & Wagner, 2017). The dimensions, morphology as well as the matrix
of the starch are altered with the treatment process which eventually results in the
formation of good quality nanocrystals (Khan, Saeed, & Khan, 2019). Through the treatment
of mild acid, the crystalline part of the starch can be isolated, as they attack the amorphous
granules making it more crystalline (Pelissari et al., 2019). Some starches usually consist of a
two-phase pattern of hydrolysis. The process of hydrolysis is done with the help a low
concentration of strong acid, which is 2.2N Hcl. Angellier, Molina-Boisseau, & Dufresne,
(2005) distinguish stages of acid hydrolysis. It is believed that the initial stage of acid
hydrolysis hydrolyses the amorphous parts in starch granules whereas the second stage is
usually associated with the erosion of crystalline region. The result of the process is
crystalline starch or lintnerization of the starch (Wang, Blazek, Gilbert, & Copeland, 2012;
Kasim (2019).
2. Impact on various properties of native starch after synthesis of starch nanoparticles
2.1 Amylose content
Starch is considered as a major component of starchy foods and cereal grains (Mishra,
Dubey, Kumar, & Singh, 2018). Amylose content altogether impacts the utilitarian as well as
the physiochemical properties of starch. This can include gelling, pasting, retrogradation as
well as hardness of the cooked starch (Blazek & Copeland, 2008). The amylose content is
generally affected by their botanical source i.e. cereals, legumes, tubers, etc. (Akturk, Guler,
Erol, Goller, & Kucukbayrak, 2020). Amylose content in starches is generally estimated by
using the iodine binding method (Williams, Kuzina, & Hlynka, 1970). It makes use of the
ability of the iodine to stain the amylose as well as amylopectin. This is done by
forming a complex of iodine as well as amylose and which results in the development
of blue colour, whereas the amylopectin produces a red-purple colour. The colour is
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not very intense. Development of starch nanoparticles (SNP’s) and starch nanocrystals
(SNC’s) results in a reduction in amylose content because hydrolysis of starch by acid or
enzymes results in a decrease in chain length in a random fashion so, amylose loses the
capacity to stain with iodine (Bailey & Whelan, 1961). Thus, during the preparation of nano
starch, some changes have been occurring in its biochemical and biophysical properties
(Thandapani, Radha, Jayashri, Florence, & Sudha, 2018) (Table 1).
Jayakody & Hoover (2002) reported that the decrease in amylose content is associated with
the fact that the reaction of hydrolysis is initiated in the amorphous region of the starch
granules. LeCorre & Angellier-Coussy (2014) reported that after synthesis of nano starch
the amylose content of potato and waxy and normal maize starch is reduced to 0, 0 and 1%
from 21, 1, 27%, respectively. They also reported that SNC’s generally consist of a low
degree of polymerization (DP) amylopectin and the amylose gets depolymerized at a faster
rate during the hydrolysis process which can explain the reason behind why no lasting
coloration is observed for the SNC samples. This consideration rules out all techniques
consisting of complex amylose with another reagent for determining its content in SNC. The
amylose content of starches also influences the yield of nanocrystals as well as the size of
starch granules (Jayakody & Hoover, 2002; LeCorre, Bras, & Dufresne, 2011). The yield,
functionality, structural traits of starch nanocrystals are stimulated via numerous factors
together with botanical beginning, crystalline pattern, and amylose content material. Starch
having low amylose content material is normally preferred for the production of nanocrystals.
Waxy starch is extra prone to acid hydrolysis than normal starches because amylose jams the
hydrolysis pathways, which reduces the convenience of hydrolysis (Jayakody & Hoover,
2002).
2.2 Pasting properties
A paste can be referred to as a mass which comprises of a steady phase of amylose or
amylopectin which is soluble. Also, there is a steady phase of granular fragments as well as
traces. Pasting is a complex phenomenon that refers to the change of starch after subsequent
gelatinization by heating. This usually includes the swelling as well as leaching of
polysaccharides from starch granules that increase viscosity due to shear strength (Tester &
Morrison, 1990). (Hoover, Hughes, Chung, & Liu, 2010). Peak viscosity is obtained during
or directly after cooking, which is evidence of paste strength generated through
gelatinization in processing (Adebowale, Sanni, Owo, & Karim, 2011). Breakdown viscosity
has been acting to show the power of maximum viscosity through processing (Moorthy,
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1985). When the granulated pea starch starts to gelatinize in water, the viscosity gets
expanded, and the starch slurry converted into a paste. The nano-ZnO (nano zinc oxide)
particles are covered by way of soluble starch, the distribution of nano-ZnO is extra stable in
plasticized-starch answers than within the water. The interaction of nano-ZnO and the starch
solution improve the pasting viscosity while the nano-ZnO content enhanced by 1 wt% (Ma,
Jian, Chang, & Yu, 2008). Paste parameters, i.E. The maximum viscosity, breakdown,
setback, very last viscosity, pasting temperature, and time taken to reach the most viscosity of
native and changed starch samples. Changes in pasting residences as a situation of warmth
moisture treatment can be attributed to reduced granular swelling, amylose leaching,
multiplied interactivity amongst starch chains, and granularity.
Paste temperature is a sign of the lowest temperature used for the starch to gelatinize.
Synthesis temperature is the first noticeable increase in viscosity and is an indicator of initial
modification as a result of starch swelling (Emiola & Delarosa, 1981). The process of acid
hydrolysis affects the pasting profile of the granules of starch greatly and this results in a reduced peak, final
viscosity, rupture as well as setback (Amaya-Llano, Martínez-Bustos, Alegria, & de Jesus
Zazueta-Morales, 2011; Sandhu, Singh, & Lim, 2007; Singh, Sodhi, & Singh 2009; Wang &
Copeland, 2012). The synthesis temperature of acid-hydrolyzed starch has been shown to
increase for corn starch (Sandhu et al., 2007;), sorghum starch (Singh, Chang, Lin, Singh, &
Singh, 2011), maize and jicama starch (Amaya-Llano et. al., 2011). H y d r o l y s i s o f
a m o r p h o u s r e g i o n s a n d c o f f e e m o l e c u l a r w e i g h t d e x t r i n p r o d u c t i o n
m a y b e a t t r i b u t e d t o t h e l o w e r i n h e i g h t v i s c o s i t y . L o w e r m o l e c u l a r
w e i g h t d e x t r i n s d i s s o l v e w h e n h e a t e d i n w a t e r . This results in a decline in the
overall viscosity of the acid which is hydrolysed by the starch. resulting in a decrease in the
viscosity of acid-hydrolyzed starch (Wang & Copeland, 2012). The reduced shock of the
acid-hydrolyzed starch may be due to the Newtonian behavior of the corresponding gel and
the lack of adequate time for the molecules so that they can align themselves
with the flow of direction during the process of measurement. (Table 1).
2.3 Rheological properties
The various properties of the SNC suspension, configuration can prove out to be useful and
valuable in evaluating the suitability of SNCs forming of the elastic packaging materials as
well as components such as filter matrix. Factors include continuous observation of shear and
storage/loss modulus, which relay on temperature, shear rate, time, and frequency (Shi, Li,
Wang, & Adhikari, 2012). The size of nanoparticles, their concentration, and the
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distribution of suspensions are known to affect the rheological properties of starch
nanosuspensions. A c i d h y d r o l y s i s o f s t a r c h e f f e c t s i n d e c r e a s e d
d e t e c t i o n o f S N P ' s a t t a c h m e n t s . T h e r e f o r e , b e t t e r S N P ' s
a c c u m u l a t i o n t u r n e d i n t o h a d t o a c q u i r e p a s t i n g r e c o g n i t i o n . T h e
r h e o l o g i c a l h o m e s o f s t a r c h n a n o c r y s t a l s a q u e o u s s u s p e n s i o n a r e
c r i t i c a l f o r p r o c e s s i n g . R h e o l o g i c a l m e a s u r e m e n t s s h o w t h e r e a l
s i g n o f t h e i n t e r p l a y u n i t i n g p o l y m e r c h a i n s . T h e e x c e s s i v e c o n t e n t
m a t e r i a l o f s t a r c h i n c r e a s e d t h e v i s c o s i t y o f t h e c o m b i n a t i o n . T h e s e
i n t e r a c t i o n s e n d e d i n a s i m p l e e l e c t r o s p i n n i n g m a n n e r . T h e p s e u d o -
p l a s t i c c o n d u c t i s n i c e l y h i g h l i g h t e d i n f a s h i o n s w i t h b e t t e r s t a r c h
c o n t e n t b e c a u s e t h e p h y s i c a l s h e a r i n m o s t u n e v e n m o l e c u l a r c h a i n s
i s i n a d d i t i o n h i g h l i g h t e d b e n e a t h e x c e s s i v e s h e a r q u o t e s . Low
viscosity values can be obtained under such conditions (Amini, Haddadi, Ghaderi, &
Ansarizadeh, 2018) (Table 1). The viscosity of SNC and SNP suspensions is not appreciably
increased and is independent of the shear rate of up to 5% solid content. Increasing solids by
2 to 5% resulted in an increase of 8 to 28 mPa for SNC and 3 to 15 mPa for SNP (Haaj,
Thielemans, Magnin, & Boufi, 2016). T h e s e v i s c o s i t i e s a r e v e r y l o w ,
i n d i c a t i n g t h a t t h e S N C a n d S N P s u s p e n s i o n s w a f t e a s i l y a n d
b e h a v e l i k e N e w t o n i a n b e v e r a g e s . H e b e i s h , E l - R a f i e , E l - S h e i k h , &
E l - N a g g a r ( 2 0 1 4 ) s t a t e d t h a t n a n o p a r t i c l e s c a n a c c u m u l a t e i n
a q u e o u s m e d i a a t s o m e s t a g e i n l e n g t h s i z e . T h e r e f o r e , t h e
m e a s u r e d l e n g t h r e p r e s e n t s t h e a g g r e g a t e d p a r t i c l e a s o p p o s e d t o
m a n o r w o m a n d e b r i s . However, the mean diameter of the SNPs obtained 146 ± 51
nm. Lower viscosity lets in the film floor uniformity, which impacts the protective homes of
the arrival and performance (Peressini, Bravin, Lapasin, Rizzotti, & Sensidoni, 2003). High
viscosity is undesirable because the dispersion of materials and visible air bubbles is more
difficult to remove, and they can cause breakage. A smooth surface effect may be
necessary to achieve uniform thickness (Peressini et al., 2003).
2.4 Particle size distribution
The distribution of the particle size is important to understand the structural and functional
relationship. The change in size of particle in terms of % intensity and % volume was
generally identified through dynamic light scattering (Shariatinia, 2019). The particle size of
starch nanostructures depends on the botanical origin and granule size and method used for
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the synthesis of starch nanoparticles (LeCorre, Bras, & Dufresne, 2010). The size of starch
nanoparticles ranged between 10-300nm and generally have spherical, lamellar, rod-like,
and irregular in shape (Sun, 2018) (Table 2).
The nanoparticle length distribution is stricken by the aggregation phenomenon, the primary
motive of nanoparticle aggregation is the have an effect on of floor fee and particle size of
nanoparticle. Which takes place due to the presence of a better attention of starch solutions.
It can be because of the cluster formation; extra starch molecules were compromised in
micrometric fraction, reducing the share of 2 hundred- 335 nm debris and increasing the 26-
36 nm percentage (Alzate, Gerschenson, & Flores, 2019).
Chakraborty, Sahoo, Teraoka, Miller, & Gross (2005) found out that the aggregation of
nanoparticles become more great because the concentration of biopolymer expanded (>2%
w/w) reporting diameters around 1 μm corresponding to massive aggregates from smaller
debris (three hundred nm) which had been found each in focused and dilute answers. The
method used for the development of starch nanoparticles also impacts the dimensions of
starch nanoparticles. The range of days for hydrolysis also increases, the sample of particle
length distribution will start shifted in the direction of smaller sizes (Zhang, He, Kang, & Li,
2018). The decrease in particle size may be due to the starch chain cracking during
hydrolysis (Shujun, Jinglin, Jiugao, Jiping, & Hongyan, 2008). Ultrasound-handled starch
led to a median diameter of 454.3 nm with a polydispersity of 0.380 at the same time as acid-
modified starch had a median diameter of 21.8 nm with an average polydispersity of 0.202
(Goncalves, Norena, da Silveira, & Brandelli, 2014). These values of polydispersity indicate
a narrow size distribution and homogeneity of the nanoparticles. The acid hydrolysis method
results in particles with a more homogeneous size. When compared with native starch, acid
hydrolysis and ultrasound represent a size reduction of about 700 and 35-fold, respectively.
The extended remedy time for the duration of acid hydrolysis might be associated with the
higher length discount when you consider that starch fragments are successively launched
from the surface of the granule resulting in small particle size (LeCorre et. al., 2011; Kim,
Park, & Lim, 2015). The pH of the suspension had a great in-after being modified by
dialdehyde, the hydrophilicity of the SNP's influence on the size distribution of the SNCs
(Wei et al., 2014). Higher size reductions for acid hydrolysis may be associated with
prolonged treatment times, as the smaller particle size results in the easier release of starch
fragments from the granular surface. The particle size of the nanoparticles decreased after
oxidation, and the particle size changed into inversely proportional to the diploma of aldehyde
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substitution. The particle size of the SNPs became forty nm - a thousand nm, which was smaller
than the size of the SNC’s (Chen, Hao, Ting, Li and Gao, 2019).
The pH of the suspension significantly affected the size distribution of the SNC (Wei et al.,
2014). The increase in dispersive pH improves the amount of hydroxyl group attached to
the starch granules, which brings about small-sized nanoparticles. During SNC preparation,
carboxyl with sulfate esters was produced on the starch surface (Wei et al., 2014). Liu, Wu,
Chen, & Chang, (2009) determined the starch collision, starch particles acquire underneath
hydrogen bond with van der Waals dispersing forces. Wani et al. (2014) found A form of
starch within a horse chestnut. A k i n d o f s t a r c h i n c l u d e s u n b r a n c h e d
a m y l o p e c t i n c o l l e c t i o n w h i c h c a n w i t h o u t d i f f i c u l t y b r e a k d o w n a t s o m e
p o i n t o f n a n o p a r t i c l e i n s t r u c t i o n b e l o w t h e h a v e a n i m p a c t o n o f t h e
s o n i c a t i o n s y s t e m a n d f o r m s m a l l d e b r i s o f m o l e c u l e s . T h e o r d i n a r y
m o l e c u l e l e n g t h a n n o u n c e d i n s i d e t h e p r e v i o u s e x a m i n e b e c o m e 9 0 0 n m ,
w h i l e t h e s m a l l e s t i d e n t i f i e d p a r t i c l e w as 2 h u n d r e d n m . T h i s m a y b e
r e l a t e d t o t h e n u m e r o u s s u b s t a n c e c o n d i t i o n s o f t h e b e g i n n i n g m a t e r i a l :
o x y - s t a r c h a n d n o n - o x i d i z e d s t a r c h . T h e l o w g l u c o s e c h a i n s o f o x y - s t a r c h
p r o d u c e a b i t p a r t i c l e t h r o u g h o u t t h e p r e c i p i t a t i o n p r o c e d u r e . For SNPs
produced by ultrasound treatment, the average size of SNPs 38 nm with a PDI of 0.2 (Haaj et
al., 2016).
2.5 Morphology
The morphology of SNPs usually varies and is primarily based on unique botanical assets and
production techniques and, therefore, variations in the length and shape of nanoparticles originating
from one-of-a-kind starch sources have been pronounced (Torres, Arroyo, Tineo, & Troncso,
2019). Starch debris are mainly oval and circular. The surface seemed to be soft, indicating that the
extraction and drying approach did not purpose extraordinary damage to the starch. Starch has hole-
formed debris, which can be because of granular swelling after which fall apart at some point of practise.
The debris generally variety from 10 μm to 30 μm (Agi et al., 2019). The shape of the native
starch is basically polygonal and approximately lies between 2.47 to 6.91 μm in length
(Arnon-Rips & Poverenov, 2016) (Table 2).Acid hydrolyzed waxy rice starch (AHW) is
round but irregular in shape (Ncama, Magwaza,Mditshwa, & Tesfay, 2018). However, their
shape changes after seven days of hydrolysis process and ranges from 20–420 nm (Montazer
& Harifi, 2017). After 10 days of hydrolysis method for the education of nano starch,
the shape modifications and it became 20–420 nm (Costa, Conte, Alessandro, &
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Nobile, 2016). Thus, it has been proved that the granular length of starch continues
on changes as the remedy of acid will increase daily (Cozzolino, Castelli,
Trabattoni, & Farris, 2016). LiFePO4 (Lithium iron phosphate) particles play an
important role as a starch solution in regulating the morphology and length
distribution of cells. LiFePO4 crystals are synthesized in low- density starch
solutions (0.0375 mol L-1 and 0.0562 mol L -1),which, as seen, show common platelet
morphology. Low starch concentrations don't have any effect on the platelet-shaped
morphology of LiFePO4 crystals because the surface energy of LiFePO4 crystals at low
starch concentrations is not stricken by those starch granule cells. The local cassava starch
grains have been rounded or ovoid alongside even surface and ranged in size from 2 to
twenty μm. The basic starch size is a polygon and the length is 2.47-6.91 μm. Acid
hydrolyzed waxy rice starch granules are rounded but not irregular in shape, 20-420 nm
after 7 days hydrolysis, and 30-300 nm after 10 days hydrolysis. A s t h e q u a n t i t y o f
d a y s o f a c i d t r e a t m e n t a c c e l e r a t e d , r a s h l e n g t h d e c r e a s e d . T h i s r e s u l t i s
m u c h l i k e p r e c e d i n g o u t c o m e s p u b l i s h e d b y u s i n g (LeCorre et. al., 2010). For
resistant starch (RS4) nanoparticles, three distinct drying modes, sonicated ethanol
dehydration (SE), freeze-drying (FD), and sonicated freeze-drying (SFD) were used by
Kim et. al., (2015). The morphology of FD cells was assessed, and it was found that the
samples contained smaller accumulated particles than acid hydrolyzed cells, and the particle
size was approximately distributed. SE particles additionally include some aggregates. In
contrast, SFD particles are smaller than others. The FD and SFD particles were small and
rounded, but the SE cells have been not abnormal in form and formed larger lumps than the
SFD cells. RS4 used with citric acid is just like native starch particles (Kim et. al., 2015).
Cross-linking within the starch unit did not affect the shape of the resulting particles.
Compared to the size of the AHW (Acid hydrolyzed waxy rice starch), cross-linked RS
cells exhibited smooth curves and were nearly rounded. The sonication of crosslinked RS
also did not affect its size, but rather differentiated individual particles. Native cassava starch
granules were rounded or ovoid with a smooth surface and had an ample size from 2 μm
to 20 μm (Lawal, Lechner, & Kulicke, 2008). C a r b o x y m e t h y l c a s s a v a s t a r c h
( C M C S ) g r a n u l e s a r e r o u n d e d t o e i g h t - 2 8 μ m i n l e n g t h . O n t h e
f l o o r o f C M C S g r a n u l e s , t h e r e a r e a f e w s m a l l d e b r i s t h a t l o o k
l i k e f l o o r d e g e n e r a t i o n . I t s e e m s t h a t t h e s u r f a c e o f C M C S
g r a n u l e s i s t o n s t h i c k e r t h a n l o c a l c a s s a v a s t a r c h . I t h a s b e e n
l o c a t e d t h a t a c i d s a n d a l k a l i s a t t a c k a m o r p h o u s a r e a s a n d l a t e r
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e s p e c i a l l y c r y s t a l l i n e r e g i o n s (Wang et al., 2010). This experiment resulted
within the speedy dispersion of hydroxyl ions (OH−) in amorphous regions due to the local
cassava starch being much less compact than amorphous regions on the floor of the particles.
This outcomes in floor carboxymethylation approximately starch debris and low DS values
(Wang et al., 2010). Liu et al., (2009) reported that waxy corn starch nanocrystals contain
platelet-like particles of 15- 500 nm width, which are obtained after prolonged
hydrolysis, and these nanocrystals are commonly observed as aggregates with an average
size of 4.4 μm.
2.6 X-ray diffraction
The main reason for using X-ray diffractometers is to evaluate the crystalline kind of
variety of starch-based on the peak intensity and diffraction angle of peak (Romani,
Hernandez, & Martins, 2018). There are basically three kinds of patterns for X-ray
diffraction depends on the organization of amylopectin crystalline lattice in starch granules
which divide starch into the category of A-, B-, and C- type (Falco, Randazzo, Sanchez,
Lopez-Rubio, & Fabra, 2019). Crystalline type of starch after hydrolysis and native starch
was similar. However, hydrolyzed starch tends to have some stronger peaks (Muxika,
Etxabide, Uranga, Guerrero, & De La Caba, 2017).
The studies confirmed that unique adjustments carried out to extraordinary starches might
have an effect on within the wonderful alternate of starch crystallinity class. In trendy, acid
hydrolysis remedy become no longer initiated to cause a enormous trade in starch
crystallinity kind. An observation in potato starch verified that HMT provoked a alternate
from B to A type even though the crystalline sort of rice starch with A-kind diffraction layout
persist unaltered after HMT (Zeng et al., 2014). The common crystalline size is from 4 to
twenty nm. These nanoparticles are dispersed inside the amorphous nature of starch
nanoparticles. The comparative crystallization was evaluated according to the manner
mentioned by Lopez, Garcia, & Zaritzky (2008). The decrease in relative crystallization is the
destruction of the lengthy-variety order related to the arranged shape of the crystalline and
undefined areas in starch granules after ultrasonic treatment (Chung & Liu, 2010; Boufi et
al., 2018). The XRD model of crosslinked particles does not have sharp peaks and is alike a
smooth counter within a lump at curve 2Ɵ = 20◦, which indicates a mostly amorphous
structure with finite crystallinity. The crosslinking reaction causes differential molecular
forces and weak hydrogen bonding between the molecular chains of starch and thus
dissolves the regularity of the starch molecules and, furthermore, their crystallization ability
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is reduced (Li et al., 2009; Li et al., 2008). After the cluster amylopectin dissolved during
gelatinization, A-style crystal formation disappeared. The breakdown of starch granules is
also possibly to result in a lack of crystallinity. Because of the solvent content, alkaline starch
molecules with warmness treatment create chemical bond breakage, main to the breakdown
of starch debris (Sangseethonga, Ketsilp, & Sriroth, 2005) (Table 2). Starch gelatinization
has led to the degradation of CMS, which can prolong the low molecular weight starch
chain (Qi, Luo, & Lu, 2018). During cooling, the gel network is formed because amylose
molecules are trapped by hydrogen bonding. The importance of damage in crystallization
is important in applications such as making superabsorbent hydrogels since the formation
of amorphous granules contributes to water erosion (Nakason, Wohmang, Kaesaman, &
Kiatkamjornwong, 2010).
2.7 Fourier-transform infrared spectroscopy (FTIR)
FTIR spectra are reactive to the distinction within the starch structure on the fast-increase
molecular order, typically crystallinity, starch chain edition, helicity, water substance, and
retrogradation (Van Soest, Tournois, de Wit, & Vliegenthart, 1995). It has been used as a tool
for differentiating between different patterns of amylose appear in granules of starch.
According to the researchers, the IR spectrum of starch was determined by the peaks near
3500, 3000, 1600, 1400, 1000, 800, and 500 cm−1 (Zeng, Li, Gao, & Ru, 2011). The gelation
and retrogradation matters of amylose and amylopectin have been taken into consideration
via utilizing the FTIR system (Goodfellow & Wilson, 1990). FTIR spectra profiles showed
the multiplied amorphous location in corn starch deal with extrusion at particular moisture
content i.E. 50 and 30% (Htoon, Furis, Crooker, Jeong, & Klimov, 2008), although the
reduced amorphous region was seen in the same sample treated with debranching treatment
(Sun, Wang, Xiong, & Zhao, 2013). Structure of A- and B-type of starch has been identified
using polarized light microscopy, x-ray diffraction, and FTIR spectroscopy. Both the type of
starch granules is presented with degrees of crystalline of 31.95% and 29.38 % (Zhang, Li,
Liu, Xie, & Chen, 2013). Due to the chemical similarity between starch and SNCs, the film
containing SNCs as a reinforcing agent confirmed nearly the equal FTIR spectrum as the film
without SNCs (Cao, Chen, Chang, Muir, & Falk, 2008).
2.8 Biocompatibility and cytotoxicity
The biocompatibility of starch debris is encouraged by using physicochemical
properties. Surface alternate as well as particle size are the key factors which
have a major impact on biological interactions of nanoparticles and mobile
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