Kind: captions
Language: en
uh CP of uh Professor P so Professor
asop Pand is currently distinguished
scientist at the center for Innovation
and translation research and also in the
csrr Indian Institute of tech tech
toxicology research in LNO India and
also he is a executive director honorary
at the Center for Energy and
environmental sustainability India so he
has published a lot of publication and
said that now it's more more than uh 1,
400 it might be now more uh and also he
uh wrote
books uh book chapter and Edge index
currently 96 and with the station more
than 40,000 station I think so it could
be more because this is long so he is
also on the Stanford list a top 2% with
rank number eight in the batt field of
course number one uh in India I think
uh without further Ado I would like to
invite uh Professor Pand to uh give the
lecture I think gur uh Professor Pand is
already have a able to share
the
yes please for thank
you for
can you see my screen please uh yes C
very good thank you uh thank you for uh
uh invitation and I really feel sorry
that I could not join your uh uh last
meeting yes okay sorry thank because you
know that uh it becomes very important
and since it was annual review of The
Institute my presence was a kind of
mandatory yes so uh
my index just to let you know is now
104 oh yes yeah cations are a little
more than 48,000 yes yes and in on 18th
November probably you might have uh seen
or known uh every year this uh uh clate
analytics they bring out the top 1%
scientist in the world and that list is
out now on 18th of November just a week
ago and uh in that list uh uh obviously
my name is there and uh uh apparently I
am ranked number four in the world
although they do not give a ranking but
uh since uh they and they have taken my
interview in fact this interview is
there uh on the website of Cl I I I'll
send you a link and I would want if you
could uh share this interview with your
uh younger it can be of course listened
by anyone but could be interesting for
your younger younger colleagues and
students all right so uh I'm going to
talk to you now uh about uh this lecture
which is on solid state fermentation
opportunities and challenges there's a
title given to me by uh you uh
so uh to begin with just uh briefly I'll
introduce me my introduce all of you my
Institutes so this is what you call csir
map of India as you can see this map of
physical map of India csir has uh uh 38
uh Research Institute which are spread
in different part of the uh country and
each of the laboratory has a very
different mandate altoe 38
labor approxim
to
this
is on the the photograph you see on the
right side upper side uh Indian of
Toxicology research this is in the city
called city is called LNO which is the
capital city of utar Pradesh the biggest
uh state in India and in fact uh this is
very close lakau city is very close to
my hometown about 200 kilometers from
here so it's very different after
working 30 years coming back to North
but then I'm happy about it so uh this
is the uh uh few more detail about my
current Institute that is um Indian
insute of Toxicology research so this
institute was established 55 years ago
uh where the its main scope was uh uh uh
industrial toxicology and uh slowly over
the period of time
uh occupational toxicology also became
uh its activity and two decades we
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and then
uh
sorry
have more than 200 Industries we have
served in fact this is one of our
mandate so more than 200 Industries we
have served in the last uh three decades
or something like
that apart from that we participate in
all the important National Mission
program which have anything to do with
toxicology and uh uh we also are heavily
involved onto predictive risk assessment
as well as um other kind of uh risk
which are involved
uh uh into uh industrial uh
research so if you look at activities we
have primarily four verticals the first
one is
basic
plan this is one common in any
organization then we are second
vertical safety assessment and
led by the in regology and if anyone to
obtain it it is not only food material
for example if someone has to put uh go
for commercial ization of any uh
cosmetic products or uh any product
which is for human need or human use or
any product which is to be uh left in
environment then it is necessary to
obtain regulatory clearance and we do
the uh different levels of safety
evaluation uh uh for that product then
of course uh uh we are also as any
research organization human resource
development various kind
[Music]
this
per se uh so we take up collaboration
and partnership we have several uh it's
more it's now four years and little more
than three years I am uh taking care of
the center and we have large number of
starts up large number in the sense in
last two years nine starts up have
established have been established here
and uh several industrial consultancy
product including launching of two
Industrial Products one of them is very
uh useful that is oir it is a water
purification system which uh does not
require even uses of electricity and uh
it has different modules
IND collaboration with technological
solutions
so from our own Institute s or from
other
organization
collabora Partnership
of could be hiring of analytical
facilities or what so different kind of
options are there so this model is one
of the new ncsr system and we are
experimenting and it seems that it is
working quite
good so now I'll move on to the our
lecture topic today solidate
fermentation so essentially uh all of
you know it's a it's a very classical uh
kind of fermentation is a cultivation of
microorganism under controlled or
uncontrolled conditions in the absence
or near absence of free water so the
bottom line is that there should not be
any free water and depending upon the
kind of f stock if you f stock the water
content could be anything
betweener to 20 or even 30 so uh it's a
classical fermentation has been used
since have to D upon that
but the again products Etc which are
currently being produced commercially us
think
[Music]
fermentation steroid in factal
and
sign so uh we generally know that it is
ideal for growing filus fungi but then
in science there are no limitations and
we have proved that uh even uh different
kind of bacterial culture could be well
cultiv cated and uh exploited uh to get
uh quite competitive yield in fact
Superior than whatever has been reported
in U uh liquid
fermentation so traditionally it has
been used for food fermentation we all
know that uh the countries in uh not
only in Asia not only in Africa uh Latin
America but even Europe also have been
using it for traditional food
fermentation for example k fermentation
and for Europe when we talk of it is
essentially the cheese
fermentation
what the interest for solic
fermentation it has a much lower water
consumption water is one of the critical
element for the sustainability in the
world and we know that uh almost 60%
part of the world are water stess today
so if we could reduce the water
utilization uh effectively that will
also not only help in sustainable
development but also lead to less
production of industrial influent so
these are the very important U
consideration this is uh where the word
again and again keeps looking at
solidate
fermentation so some other information
that what are the specific applications
uh where there is a lot of focus and uh
interest for commercialization is in
specifically in food now functional
foods and food ingredients in
agriculture areas by fertilizers in
Pharmaceuticals so functional bioactive
ingredients secondary
metabolites and then specifically
enzymes which have been you know one of
the core uh
commercial strength of solate
fermentation so we are today looking at
cellus production Alpha proteas Etc and
on
livestock probiotics probiotics for
human consumption probiotics for animal
consumption and if you look at uh uh uh
the right side figure that uh which
organism or which products are being
utilized which cultures are you being
utilized by which industry so it's very
interesting and uh in spite of uh you
know not being used currently as a high
technology it continues to grow in
different parts of the world uh for
multiple
applications so if look at the pros and
cons when I say it continues to uh grow
for commercialization or for research
perspective in different parts of the
world and advantages you all know
because all of you have been working
into this area that uh it has a low
Capital cost it has reduced energy
requirement it has a low affluent
generation it does not have one of the
sever problem what we face in some
fermentation is foing and in fact foing
is the one which often
causes contamination in large scale
fermentation
Etc and uh also an important fact as a
researcher you uh need to know that a
question is often asked why we get high
yelds and high productivities in
solidate
fermentation so uh it's it's only a
speculation it's only hypothesis it has
uh uh been proven to certain exent
extent but not uh absolutely in not not
in absolute terms that why there are
higher uh yields and why there are
higher productivities obvious apparently
it is because in solate fermentation the
microorganism which we use naturally are
fungi or some kind of yeast and
bacterial culture and since uh their hom
Town what we often refer in our
reference that Hometown that means the
place where we are born where we are
comfortable where we where we know the
neighbors we know where we know the
people so Hometown for this culture
which we utilize are in solid state and
then it has very hetrogeneous uh you
know uh surroundings and this is what
happens in case of solist fermentation
that the substrate condition is solid
and it is very heterogeneous in nature
so apparently this could be you know
related with their better performance
for higher productivities for higher uh
title so uh in spite of the fact that
there are lot of advantages is
specifically you know the the the in the
area where we have very serious concern
that is uh uh sustainability
specifically for water and specifically
for industrial affluent and also about
the energy consumption in in uh several
parts of the world uh including uh more
specifically that developing countries
so all these uh advantages add up for
the use of solidate fermentation but
then we have several
uh uh negative point what you call
disadvantages so it has less automation
we all know and online monitoring is not
possible what is happening inside the
fermentation medium fermentation bed it
is labor intensive that means because
automation is less obviously it is a
labor
intensive mixing is difficult and this
is one of the very strong negative point
for solic fermentation specifically when
you go for scale up because then Mass
transfer uh is
uh obviously not homogeneous and there
is a heat built up and carbon dioxide
accumulation so these two are one of the
are the major negative points still not
have been able to this is in fact a very
strong chemical engineering uh uh
problem and I can tell you that I have
been collaborating still continue to
collaborate with Scientists from uh uh
one of the best institutes or
universities in the world
from us from France from Germany from UK
and so on you know and uh I've been
collaborating with chemical Engineers
trying to tell them that this is the
issue you have to take develop kinetic
models and look at heat and mass
transfer effects and try to understand
how they could go be how this could be
taken for a scale up engineering
parameters and so and so forth but then
uh none has been able to resolve this
and until and unless we are able to
understand this for scale up that how to
tackle Mass transfer and heat built up
removal without affecting the growth of
microorganism without impacting their
metabolic activity both are important is
just not the growth but then their
metabolic activity to form the desired
product is also very critical and very
important so that must uh be understood
and then only we can go for scale up and
once we are able to understand obviously
there will be drastic change in
commercialization of solid state
fermentation so related aspect in this
regard is a poor Iration because the bed
is solid bed is heterogeneous so we we
find that uh the uniform areation is
very difficult it is related with the
particle size it is related with the
interparticle space and so on so this uh
these are the related issues and uh
which ultimately
uh lead difficulties in scale up
and
uh then uh overall the process uh
becomes very laborious or uh we need to
develop large number of reactors
requiring then higher space and so
on so this is overall fermentation
process we have preparatory step we have
main fermentation
we have manufacturing stages so raw
material procurement uh normally these
are this
comprise agroindustrial residues this is
one of the advantages in fact of solate
fermentation that different kind of
agroindustrial residues coming from uh
different crops crop residues or for
example paper and Pulp industry residues
and uh uh other uh uh Industries which
are essentially Agro based their
residues could be utilized as CD stock
for solate fermentation that is one of
the advantage because by using them
again we have two advantages that one is
the cost we have lower cost and also
second is that we help some way in
development of sustainable green process
by using
them then we have uh the second one is
the uh Water Act the microorganism
example is given of your probiotic but
depending upon the need uh to develop
what kind of product we want to study or
want to produce we have to look
microorganism very carefully each of
these are very important in fact most of
the researcher have taken both of these
aspect very casually and that is where
we even are not able to publish high
quality research paper in today's time
when we talk of solicited
fermentation because we need to put our
mind into that and go into looking uh
newer aspect and how to Define the
research in a sense that it could have
uh uh some novelty and it could have
aspect of developing a process which has
IPR POS generation possibility and which
could be uh thought by someone uh for
commercialization then water content is
uh again very important at uh uh it is
related aspect and macr growth is
directly governed by water content in
fact I will devop on these all details
little in more detail little later then
functional ingredients sorry there is a
mistake in functional functional
ingredients because depending upon kind
of microorganism we are using we may
need to provide a different kind of
nutrients specifically for some uh
products otherwise in most of the cases
since we use industrial residues which
are rich in organic uh know content and
also which have which also provide or
supplement uh uh you know uh growth
factors that is nitrogen is there
different kind of Trace metals are there
so often it has been seen that we don't
need to supplement many things in solate
uh fermentation
medium so but in certain cases we may
require to add certain things then we
have and looking at wind fermentation we
have things to worry about the
temperature of ambient temperature
obviously the better temperature we need
to motor and we need to we can try to
control but it's not easy then we have
issues of Iration and mixing as far as
possible to you know uh do the Iration
com comprising moist air as far as
possible and if
require we need to go for mixing but
then this is a difficult issue because
you know if you mix it for example if
you take
uh uh uh fungal culture it they are uh
you know they have melium and if you do
mixing along since they are uh interated
with substrate particle mixing could
lead and rather leads breaking of those
Melia
so uh and if the my are broken it it it
impacts their growth and it impacts the
product formation so usually mixing is
uh desirable but need to be controlled
at very very low rate that is could be 1
or 1.5 or
two uh RPM and so on so it has to be
done and it has to be uh thereafter uh
uh uh you know
evaluated we need to study the macral
growth that how it is being impacted and
it is not the growth only we need to
also monitor the product fermentation
and again water content as I said that
uh there are Pockets sometime there are
Pockets where there's a lot of
condensation taking place and those
places water content become very high
and that leads uh you know uh poor
growth or poor formation of product
product so that is to be very carefully
again
monitored and there could be situation
that we need to do in two
stages or single stage in some product
formation uh anerobic process becomes
secondary and the first stage we grow
the cells and thereafter in second stage
we control the uh gases environment in
order to uh produce the product in
higher
quantities then we have control as is
mentioned that we need to look about
water
content uh temperature and
mixing and then uh of course the product
is there product isolation and packaging
Etc so let us look at this uh points in
little bit more detail that uh uh as I
mentioned that previously that
microorganism selection of microorganism
is very very critical and very important
uh for solate fermentation processes and
then what we need to understand that uh
what kind of St selection is very
critical and very uh Paramount if we are
not uh simply taking any strend from
environment and simply making a study on
some product is not a scientific study
for a researcher who is intended it may
be good for a uh you know to begin with
uh someone starts master's degree look
at the microorganism try to understand
how a culture is isolated how in medium
is produced how what is the way to you
know look for a specific culture and so
on so much but then for a specifically
when you look at PS student all that
they
must first understand that even if
you're going to isolate this St from
where to isolate there are certain
governing PL principle keeping into mind
what is the main target one product is
main target or to utilize a feed stock
is main target uh or
what so uh stain selection you need to
look at at then discuss with a
microbiologist specifically someone who
is uh very ver with the taxonomy so we
have to keep into mind product
properties and taxonomy product
properties and environment product part
properties and the presence of substrate
method of isolating uh organism it is a
enrichment or it is a negative selection
and then also we need to always keep
into mind uh since there is a human
involvement safety measures we need to
ensure that we are isolating at first
point uh generally recognize as sa grass
cultures unless and until there is very
critical need to look for some uh
organism which even if have
pathogenicity we could handle them
provided the lab is provide is in having
uh safety level two safety level three
facilities so that is the first point to
keep into mind when you start isolating
the
microorganism another important point is
about strain
development uh we know that by
adaptation is one of the very important
aspect for micro B cultures and by
adaptation we can make several changes
it is never necessary that we look only
for genetic tools or molecular tools for
modifying the
microorganism uh because you have to
keep in mind that uh again looking at uh
human behavior uh you know if somebody
is not behaving properly if child is not
behaving properly by you know love and
affection by some way or other by
teaching uh uh in a proper manner by
giving proper food by providing proper
living condition we can change the
nature of child or even of those are
grown up including the researcher
sometime we don't get every researcher
on the same platform someone is not you
know as serious as others so it is a
teacher it is a success of teacher to
adopt that uh bad boy or bad girl into
right path and this is what exactly
happens with the macrobial cultures we
need to adopt them we need to train them
we need to provide them proper feed on
right time and so on then the culture
start behaving the way you want
obviously it it is practically
impossible that the the microb is
producing product a and we want it to
produce product B that is probably not
possible unless there is a broad
relationship and then we need to adopt
molecular tools to change this
property then we also look have to look
uh methods of strain development
uh what is as I mentioned what is that
we are trying to achieve and which
method classical methods to begin are
the best methods and we don't have to in
fact keep looking uh always that for St
development we need to look at uh
molecular tools or genetic engineering
tools I would not uh suggest that
although if this collaboration is
possible it is always good to keep
running it as a parallel
stream then St stream meant main this is
again a very critical element and uh in
my uh you know knowledge all over the
world where I have been working or
collaborating with the
researcher majority of the people
absolutely ignore this point at times
often uh transfer from solid medium to
solid medium or solid medium to liquid
medium and maintaining on liquid medium
is not good and at time too long
preservation and thereafter transfer is
taking place that also is not too good
so depending upon the uh nature of
microorganism the transfer should be
uh done the stain maintenance what is
the temperature of Maintenance uh and uh
uh which kind of storage you require
shortterm longterm medium-term
accordingly the things should be
selected and this information are
normally available in classical uh
microbiology book General microbiology
book all this information one can find
or in fact today is uh you know internet
uh time if you Google it uh a lot
information you can get but of course
you also have to use your wisdom to
decide the information which has come
from Google which one is the best and
which one to be used utilized not
necessarily that uh whatever information
you find on Google is all
correct so uh it is also important that
we need to uh choose right process I'll
give a very specific example now in next
this slide and next two three slides
where a strain uh which has been uh
which have been used using some method
here example is shown by mutation and
three kind of fermentation techniques
have been utilized for them so his of
ropas as you can see that four kind of
muts were done
and this St have been referred as R35
and so on right and when this Sumer
fermentation was uh done for uh uh an
enzyme production as you can see uh the
four different strength gave four
different kind
of uh enzyme activities so the best was
by the fourth
one but then the same culture when it
was used as surface culture but in sub
much fermentation the enzyme units are
substantially high if you look at the
first culture they are almost 9 time
more and so on but the fourth one was of
course about 1.7 time more but then when
the same culture was utilized in solid
state fermentation if you look at the
yields this was approximately know few
hundred time and here if you look at the
last one it is uh more than uh uh 124s
so this is a judicious uh you know uh
decision to be taken by researcher and
uh nothing should be left unexplored and
that is what what is called basic
research so there should not be bias for
so much fermentation there should not be
bias for solic fermentation and a
researcher anyone who would want to use
one of these fermentation my strong
suggestion would be that do not leave
out any possibility any process
because you never know where there is a
brighter silver silver line right now
look at this line This slide now we also
again are working need to choose right
uh process look at uh utilization of
carbon Spectrum so uh there's a culture
of
again fungi that is this time is is
tricoderma tricoderma V fermentation and
uh so suppose uh you are exploring that
you have a culture and you have been
targeting to produce alpha males you
know and that is how you started looking
at isolation of the culture that is how
you started looking at literature and
then uh did the isolation and so on so
if you have been using these the sources
for enzy production you found that in uh
uh different depending upon different
carbon Source uh enzyme uh units varied
hugely lactose which could be well
expected because trma cannot utilize
lactose but then trma definely can
utilize sucrose depending on the
concentration but it still produced only
17 units per milliliter Al amales and
when corn starch was used in the medium
the enzyme production was substantially
high that because we were looking at Tic
culture and obviously when there was
starch was there the enzyme ructions are
substantially high but
then at the same time the same culture
when used for Proteus
production if you look at lactose so
just now I said to you that we know that
tricoda cannot produce cannot utilize
substantially or in a preferred manner
lactose but when uh you look at enzyme
system and the metabolic activity of
this culture we find that it is still
produced 175 units you know uh proteas
enzyme and when sukrus was the medium
the activities were substantially high
as as high as keeping into a maltic
nature of the culture 351 units so equal
quantity of uh uh proteas was produced
whether F or the substrate was corn
starch or substrat was sucrose and in in
any case in all cases the proteas enzyme
formation was far more High except when
the maltose was substrate then the alpha
males now the the point is that we were
looking this culture for the production
of alpha males but if you look at this
enzyme formation we can understand the
major focus of metabolic activity of
trod vity was not on Alpha malus
production rather it was on protus
production an enzyme which was not not
our targeted enzyme so carbon was wasted
carbon is being wasted here metabolic
activity is diverted for some on a for a
product which we do not want to produce
so that means use of this trodd for
studies on alpha males is not worth to
carry forward even if we ended up
isolating this culture that means so uh
what is the message here or what we can
conclude from this slide that if you're
working on enzyme production at least
you must also look what are the related
Associated activities the culture which
we have isolated is go is producing this
very important to understand in enzyme
production Associated activities
sometime have much more relevance uh
than uh the main product I'll I I I'll
tell you about this a little bit more
when you move on to last part of uh the
presentation so then comes the issue of
micro organm this is one of the very
very critical uh point I have mentioned
earlier also to you uh that selection of
right kind of macro organism is very
important and how do we do it now
normally we will refer to literature and
uh suppose we are interested in
production of alpha males and then if
you look at uh literature you will find
to know that oh my God I'm sorry it has
lot of
Animation more than uh uh you know three
four dozen five dozen microorganisms are
reported into literature and several of
them in fact those which are shown in
red fun have been claimed to produce in
quantities which are commercially
feasible there are several asperous
species without any species then they
also have been reported in literature as
producing significant quantities which
are commercially feasible acceptable
quantities of Fales so this is another
slide you know we reach up to uh several
bacterial culture the previous one this
is uh if you look at uh fungal culture
normally they produce enzyme alpham
which are food application while for
other application laundry application
detergent application uh leather
industry application enzyme usually is
from bacterial culture so if you look at
here in this page also you can see at
least three cultures have been uh
defined or you can find their
description
for
commercially commercial applications we
continue the
list and then we still continue the list
so 64 micro organisms are reported or
have been reported into literature which
produce uh Alpha amales and these are
the research or patent information so
which one you are going to use if your
target is Alpha Amal so you need to
understand firstly the application if
you are primarily looking food
application then it is good to look at
uh uh fungal culture and if it is
for other application it is good to look
at at uh bacterial culture and then
thereafter we need to produce if you
look at the couple of slide which I
showed that strain selection slides that
what are the parameters we need to
consider then perhaps we would be able
to make a right
choice now we continue to this one that
need to choose right microorganism this
is one aspect I mentioned about the
formation of one product but if you look
at uh this one uh
suppose we have a
culture and we want to produce uh we
want to use it example is sh enzymes
produced by it's very strange kind of
Animation
sorry so asperous Niger has been uh if
you look at literature again has been
reported to produce at least 21 kinds of
enzyme and those which are shown in red
fun in the slide are the one where there
are patients claiming that it produces
commercially feasible or commercially
acceptable uh quantities of
uh uh enzymes these enzymes so how do we
make a selection suppose we have a
strain and if you start working only on
um uh tnis production possibly it may
produce better zenes or
suppose our focus is z xenes production
and we have a culture of as pilous Niger
and we think that yes it is producing
good quantities those that good is very
in fact dangerous word in scientific
research writing good
significant High quantity these are very
relative terms and unless we Define that
how do we claim this good comparing with
literature unless we Define this
significant quanti is comparing with
literature sorry it's not very good idea
so
again if you have taken into
consideration that what is our main
targeted product and if you try to
keeping this slide into mind also
evaluate at least Associated activities
being produced by Asus Niger then
perhaps you would be able to decide that
whether my strain of asparagus Niger is
good to produce xylon or
not okay
so we move next now we have uh uh
understood all those Point very well so
we look at process uh methodology
now preparation of solid substrate
sterilization
process rising of suitable
inoculum then inoculation of the moist
substrate incubation in appropriate
culture vessels or reactors maintenance
maintenance of optimal
conditions primarily the pH temperature
Iration flow method Etc then harvesting
of fermented
solid drying extraction of product and
further down string processing if
necessary so selection of microorganism
I have already uh gone into great detail
and then we have uh substrate as I
mentioned that uh it uh depends upon but
normally agroindustrial residues should
be taken are utilized as a
uh P stock then we go on to process
optimization looking at the basic aspect
of
process uh and then product isolation
and purification in case of enzyme
largely we feel that it should not be uh
necessary at many time uh to to isolate
the enam for example in talk of biofuel
production the enzyme which are uh which
are produced in ssf the W substrate
medium directly should be mixed with uh
the
the pre-treated substrate for hydrolysis
and and we are able to show it that it
is far more effective and obviously it
is far far more economical large number
of process steps have been removed large
number of losses have been uh the enzyme
losses have been removed and uh uh
obviously the cost have been removed and
and then uses of water and the time Etc
everything uh such uh everything has
been
removed so preparation of solid
substrate we know that uh uh we need to
add uh uh
water and when you go for scale up we
should try to avoid using even uh
distill water depends upon if uh you
have uh uh the Water property what is
available from Municipal Supply your uh
Institute what your pallet plant
whatever if it has
a pH desirable pH and much more than if
it has uh not any heavy metallic
impurities heavy metals or
calcium and so much so on then uh we
simply can
utilize boiled hot
water ization of substrate
as say that we can go
for normal aut caving method we require
longer time uh because uh compared to
liquid fermentation because it's a solid
bed and depending upon the bed height
the time
of
sterilization is fixed in fact this is
one of the uh negative Point suppose we
would like to or to CL a bed of 1 meter
there are reactors one of the first such
reactor was developed uh in France where
they claim that they can do calization
without having uh unsized Pockets uh
effectively uh but then it could not
still get commercialized because of some
of the uh problems and of course one of
them has been the high cost involved
into its uh
Fabrication in ulum uh preparation and
this is again one of the uh uh positive
point because uh uh most of the time
when we use a fungal culture we you can
utilize spores and in fact spores can be
produced in large quantities and stored
at uh uh you know low temperature so in
lesser volume we can produce uh High
High number of spores High number of
inoculum store it and utilize depending
upon as and when required even if it is
a direct M inoculum this is also
achievable in much easier way when
compared to other
processes then inoculation of the moist
substrate so when it is a product
formation for example enzyme or organic
acid or estro Etc it is always good to
use spores
and their uh mixing is not a uh
difficult issue it has been well
achieved at larger
scale but when it is a for example
single cell protein usually then
use or cage the normally we use inoculum
of fungal Mycelia and then at times this
also poses some issues in the Sens some
places the M spread is not uniform
because of the heterogenous nature
of uh substrate then optimal condition
uh pH is one point that must be taken
very proper care because you know that
if you use agroindustrial residu
specifically if you use uh uh
uh uh Solid State uh
bed there is
a there is a this this uh
medium have very strong buffering
capacity for example if you take wheat
brand if you take rice straw rice brand
all these have very strong buffering
capacity so it will not be possible
suppose unlike liquid fermentation where
we
take for one normal sodium hydroxide or
one normal uh hydrochloric acid and set
the pH of the medium in case of solidate
fermentation that is not possible if you
add one normal
uh hydrochloric acid and thinking that
by this formula uh adding this much uh
uh quantity will bring the pH of the
fermenting bed to medium to 4.5 that is
not possible because of the buffering
capacity of this uh agroindustrial
residues primarily the crop residues so
in this case if you have it is if it is
essential to to change the pH we need to
look at uh the
pH solution for example if the idea is
to make the pH of the uh with brand
medium 5 maybe we have to prepare a pH
solution of one and then add in some
quantities and then see if the pH has
changed or not same thing is if you want
to check take pH to 9 fermenting medium
that is solid bed medium then we have to
use a very high alkaline solution to set
the pH so in fact this should be taken
as one point in favor of ssf and that is
effectively what happens when you are
concerned with fungal growth in uh
medium for enzyme production Etc we
don't have to precisely we don't have to
worry about pH temperature is important
aspect and temperature of fermenting bed
is much more important and we we need to
understand that there could be Pockets
because of accumulation of carbon
dioxide there is a uh because of the uh
aerobic nature there is a respirometric
action and then we uh today we know very
clearly that how it happens and then uh
depending upon the efficienty of the uh
you know Iration the temperature could
be well controlled limiting factor
obviously is the bed height bed
thickness and we cannot go uh in fact
something like 7.5 cm today is
considered as the maximum which could be
utilized in a normal tree kind of
fermentor and so on then harvesting of
the fermented solids depends upon
suppose if it is a single cell uh
protein nutrient Rich protein for Cle
feed Etc nothing is to be isolated for
enzymes as I said to you today for
biofuel application it is highly you
know uh desirable that we use the solid
wet fermented material that means the
enzyme production should be carried out
at in C2 wherever the P the plant itself
should have a in module to produce
enzyme and the fermented Mass should be
directly added used for added into
hydrolyzing
medium then uh uh there are again
situation where drying and extraction of
product is required uh for example you
want to produce enzyme and enzyme should
be you know extracted using a different
uh way normally water or with saline and
they should be dried uh you there could
be some filling material Etc these are
commercial secret and nobody would like
to uh know share
them so normally uh these are the four
cultures which are predominantly so far
have been reported in uh product
different prodct formation except some
patented specific processes where they
would not like to reveal the specific
name or uh uh of the culture because by
Patent regulation it is never necessary
you can say biological agent specific
biological agent property describes
property and give its ACC number in
patent
depositories so uh now let us start with
specific example that is we know that Co
fermentation uh in fact it became so
much phenomenal that for large number of
years people have been talking ssf as a
CO
fermentation so all of you must be
knowing that what is uh Co fermentation
how it takes place and uh it is one of
the very common in East Asian uh
countries and uh commercialized uh
centuries before and so on so the what
are the processes the kind of setup some
other details are given here and enzymes
involved are essentially alpha males
glucal and acid prote but then there are
several Associated activities and that
is how Koji from one industry to other
industry is very different and the
product is also very different and some
product are are become very famous or
liked much by uh the consumers and it is
only because the associated activities
which I mentioned in the beginning to
you are very different and some are able
to
utilize are utilizing some cultures
which produce very desirable Associated
activities associated activi means
production of different other enzymes in
a small uh
quantities so kif fermentation again uh
uh that uh what are the other steps and
uh uh more
details refinement is also considered as
one of the very very important aspect
including what kind of fermentation or
filtration process we are
employing so in fact people still
believe much more in Co process the
traditional way rather than uh uh going
for looking at for some uh uh newer
aspect there are moderation there are
developments but then uh it it is
primarily governed by the traditional uh
factors so if you look at this one the
fermentation process creates over 200
different flavor compounds so this is
what is very important for uh you know
the successful production and
commercialization commercialization of
uh Ki
so process parameters uh if you look at
which are the process parameters we need
to control at chemical factors as
mentioned that nutrients very important
growth factors temperature and oxygen
and then biological factor microorganism
we have already
uh uh discussed this points and in uh in
the process if you look at a specific
characterization at solid Matrix
different kind of f stock and uh of
course rice BR wheat brand is the most
common then we have liquid medium
basically it is a mineral medium
sometime nitrogen
is uh also supplemented and depending
upon the nature of rice BR is different
saw dust is different sugar be p is
different so depending upon their
chemical composition about their
minerals content we need to add
additional uh uh uh nutrients
inoculation that depends upon what kind
of process you're using product
formation using then uh uh uh we need to
uh decide doses of
inoculation temperature again depending
on the product formation it could be as
slow as 5 to 95°
and also it is directly related with the
microorganism which are using the
moisture content 50 to 85% these are you
know range given not necessary that
everything will be primarily defined by
these parameters only agitation it could
be inter intermittent it could be no
agitation and it could be a constant
rotation depending on the kind of
reactor system we are using then if you
go for uh Iration 0.5 to to five
vvm and uh duration could be up to 24
hour or fungal foration for example if
you're looking some enzyme it could be
as high as five days also it depends
directly the kind of microorganism and
product cellules production takes longer
time and xinis by bacterial culture
takes much shorter time and so
on D stream processing or
centrifugation uh for many
applications process parameters so the
size of substrate particle in fact this
is one of the very important aspect
because we have to keep into mind that
when you use a smaller particle uh they
provide larger surface area in solidate
fermentation whatever microorganism we
use they normally grow on the surface of
the substrate part
particle and so larger the surface area
larger will be space available for uh
the growth of those
microorganism but
then smaller particles even if they
provide larger surface area they also
create a compact bed and if the bed is
compact there will be difficulty in
Iration so it is uh not very good uh
situation then then if you are not able
to do
Iration uh so air penetration will be
one uh very big issue but then if you
use uh bigger particle size the bed
would be much more you
know porous vo volume will be uh larger
and Iration would be easier but then
there will be lesser surface area
available that means uh the space
available for the uh growth of
[Music]
microorganism will be less so both are
contradictive we want as large as
possible surface area but then we also
want proper Iration to take place so so
from this we understand that uh we need
to make a compromise and this is again
one of the very critical scientific and
wise decision to be taken by the
investigator that what kind of substrate
particle we have to use it has to be a
mix of uh small to smaller and then big
to bigger and this is where you have to
do the experimentation and understand
that uh
uh the level of particle size and
they're
mixing we also have uh uh to understand
substrate characteristic that excessive
water tends to aggregate on solid
particle making Iration difficult and
when the Iration is difficult the growth
will be impacted and low moisture
environment fce growth and Eastern fungi
so this could be well understood if you
keep into mind the aspect of water
activity if you look at Water activity
of microorganism that is scale water
activity is theoretically one of pure
water and uh uh the the water activity
Factor required for the fungal uh growth
is uh much lower than
uh bacteria so normally bacterial growth
is well around 0.9 water activity that
means the water should be free flowing
and this is how the basic information or
basic definitions and thoughts of solate
mation were there in the olden time that
bacterial cultures are usually not uh
good for solic fermentation but then uh
in science nothing is impossible and we
have proven that uh by adaptation and by
manipulating the growth condition and
Engineering the medium we can very well
cultivate bacterial culture into medium
and produce different kind of products
we have shown it for lactic acid product
and we have sh it for different kind of
other products uh uh using
uh bacterial
cultures so the yeast and uh uh fungal
culture depending upon the the kind of
strain we using the water activity could
be Z between 0.5 to
0 7 or even uh in certain cases uh
0.8 or
0.85 is specifically we are looking at
uh the
uh cultures fungal cultures which grow
on
uh cellic feed stock rice straw uh wheat
straw sugar can bagas and so on so in
this kind of f fungal cultures have
higher water reactivity requirement
compared to the cultures fungal cultures
which grow on a starch if it is St and
same is true for East normally East 0.5
to
0.6 uh water
activity so water control in the medium
is important and this uh in fact is done
by a uh spring uh
intermittently water and if there is a
mixing also then uh it can be well
controlled and together both of them uh
remove the heat as well as with foration
we also remove moist Iration we also
remove carbon di
oxide so from this once we have
understood that the microorganism the
fedus RO that is substrate and the
process parameters now I'll take uh
another few minutes to talk about design
of bioreactor and then we'll come to the
last part of my talk about what we have
been doing as briefly telling you what
we did and where we have
reached so uh ssf is mostly you know the
process we know at least commercial
skill are batch processes and different
kind of Bio reactors have been utilized
but then uh uh mostly uh it is a tree
kind of ferment the concept still
evolves around that it's a very
traditional uh design of stay fermentor
you can see here and this another one
that uh usually small often simple
reactors and small or medium scale
because as I mentioned that we still do
not know how to
tackle uh heat built up carbon dioxide
removal in
larger bed size and also the still the
issue of sterilization continues with
larger bed
size so Tre Bor is one of the most
common common reactor we utilize an
ssf uh also there are large number of
react reports and uh uh this also has
been uh commercialized in fact uh uh for
food processes and other uh spefically
food processes that is a kind of pad bed
reactor we have been working in
different kind of paded reactor
horizontal vertical and so on and uh
although there has been always issue
even in this um uh reactor uh about the
scalability in this mixing is uh very
well possible and uh the traditional
drum kind of reactor which resembles
like a pack bed reactor I'll I'll talk
about that also little later but then
the biggest weakness is that bed depth
we cannot go much High even in uh large
reactors cylindrical
uh drum kind of fermenter is the one
which I mentioned and it has been uh
also commercialized for multiple
application in fact specifically for uh
development of uh uh single cell protein
and uh as you can see as the visual
figure is there rotating drum and state
drum this state drum kind of reactor we
have you know air flow we have rotation
uh and we have material
so this ensures that with this pedals
which are present into this system that
uh the medium
keeps uh moving and then there is no
aeration of the medium particle and also
there is no uh
uh blocked of carbon dioxide
Etc uh here we have two ways to control
the temperature one is that we keep uh
running in a in a jacket cooling or hot
water and the other one is that we keep
passing in this Central pipe where there
is there moist and sterile air so that
also takes care of bed drying so this
has some automation that you have
possibility to keep reading at what is
the relative humidity at real time and
what is the uh know temperature
temperature of bed can be monitored
continuously temperature of the gases uh
environment in the chamber can be
monitored and those gases can be you
know uh can be
uh utilized for determining the growth
of the culture using respir
respirometric principle which are very
common today to determine the growth in
solate
fermentation so some other that is
primarily what we refer as Eed erated
Biore reactors that uh we have uh the
first one is looked at estad Ed bi
reactor the gas solid fluidized bio
reactor uh and then we have a rocking
drop kind of bi reactor and on all of
them there could be possibility of force
areation with moisture which can take
care of heat accumulation carbon di
accumulation and
also uh possibility of sprinkling the uh
water in the sense that uh
uh the can be moined and so
on this are other example that bi
reactors that rocking drum bi reactor
this is also available commercially in a
small size the first one is uh usual
that how it is there and then second one
is um uh you know uh what is happening
inside that rollers Etc are there and so
this is also this being manufactured but
only on uh a specific order given by the
client and this is very compact as you
can see this is how it uh looks like so
uh when we want some Automation and we
want to move from laboratory process to
some level of uh
scale up this is one of the important uh
development and this reactor could be
utilized for enzyme production for other
product formation
Etc this basic design in all kind of uh
uh this 34 uh reactor I showed to you
that uh and with much more automation we
have exhaust gas analysis uh no
possibility online monitoring we have
liquid Supply possibility we can spray
it we can pass through the uh Mo then we
have in the center pedal type for mixing
because this is the one which is
considered most efficient even not to
damage The Melia and if it is a uh in
fact in real time we can also continue
to uh extract the product when it is
formed into the medium by you know
simple passing through the liquid that
it could be s plan it could be just
water and then uh uh monitoring
of growth monitoring of uh temperature
monitoring of uh uh uh
medium
uh humidity can be
online so this in a setup how it looks
like that what are the things we require
in a laboratory that we require a
obviously to stock the culture in a cold
we require cold room for fedock ETC
clean bench for a septic work incubator
and then different kind of other
fermentor Etc and uh
uh what kind of fermentor you can you
would want to buy and what are the
Avenues for you to procure it several P
kind of P