Preface - kmutt

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production demand. Nevertheless, the system
conditions in general could return to normal
within a few days. With three more open ponds
connected to the system in series, the efficiency
of the entire system could reach 90% in COD
removal ability. After the AFF lagoon was
covered to collect biogas in order to generate
electricity used within the factory, the power
expense was reduced promptly about 350,000
baht a month. More importantly, the cost of
setting up this type of AFF system was
significantly cheaper and far less troublesome
compared to the normal AFF plants.
NC-352 IMPACT OF BIOGAS
RECIRCULATION ON THE
CHARACTERISTICS OF A LAB-SCALE
ANAEROBIC HYBRID REACTOR
วรกฤษ สุวจิตตานนท, ธนา จําปาทอง, อรรณพ นพรัตน
BioThailand (The 16 th Annual Meeting of the
Thai Society of Biotechnology: The Era of
Bionanotechnology), 4-5 พฤศจิกายน 2548,
ศูนยการประชุมแหงชาติสิริกิติ์, กรุงเทพฯ, หนา 119
An anaerobic hybrid reactor (AHR) is a
type of reactor relying heavily on the biofilm
formation on the supporting media. To reach its
high performance sooner, the acceleration of
biofilm growth would be necessary particularly
duiing the start up period. To increase the
amount of biornass on the media using biogas
recirculation, one of the problems that usually
might occur is the biomass washout. Therefore
proper flow rate should be carefully applied to
the system to provide more benefits than
troubles. The gas flow rates of 1.8, 2.7, and 3.6
vc/v/d were selected to study their impact on the
characteristic of the AHR system in lab scale
during the treatment of a synthetic wastewater.
The acid accumulation was found in the system
over the operation period causing the pH to drop
below 6.0 and the removal efficiency below 60%
with the low flow rate, while the highest flow
rate used caused too much wash out problem
which could deter the system performance in a
long run though the treatment ability remained
favorable at the moment. The system seemed to
work relatively well with the gas flow, rate of
2.7 v G /v/d, both in terms of treatment efficiency
and biomass accumulation. The COD removal
efficiency could be maintained above 70%
comparable to the flow rate of 3.6 v G /v/d but
much less biomass wash out.
KMUTT Annual Research Abstracts 2005
NC-353 GERMINATION AND
TRANSCRIPTIONAL REGULATION OF THE
GENES RESPONSIBLE FOR GERMINATION
OF Mucor rouxii ARE AFFECTED BY
CULTURE OR SPORE AGE
วรพงษ กีรติศักดิ์, สุภาภรณ ชีวะธนรักษ,
ทวีรัตน วิจิตรสุนทรกุล, มรกต ตันติเจริญ,
ศันสนลักษณ รัชฎาวงศ
BioThailand (The 16 th Annual Meeting of the
Thai Society of Biotechnology: The Era of
Bionanotechnology), 4-5 พฤศจิกายน 2548,
ศูนยการประชุมแหงชาติสิริกิติ์, กรุงเทพฯ, หนา 239
Morphogenetic program of Mucor rouxii
can be affected by several biological factors. In
this study, the effect of culture or spore age on
germination efficiency and transcriptional
regulation of fatty acid desaturase genes
responsible for GLA synthesis were investigated.
There was no significant difference in
germination efficiency and time of germ tube
emergence among spores harvested at 5 hours,
24 hours, and 5 days whereas a delay in both
processes were observed with 9- and 14-day-old
spores significantly. GLA content of
germinating 14-day-old spores was much lower
than that of spores of other ages suggesting a
profound effect of spore age on germination
efficiency by means of fatty acid mediated
process. Age of spore also affected the amount
of stored mRNA and the expression level of ∆ 9 ,
∆ 12 , and ∆ 6 desaturase genes. Young spores
accumulated higher level of mRNA than older
spores resulting in a prompt transcriptional
regulation of the desaturase genes during
germination process. In contrast, a sharp
increase in the rate of transcription of all
desaturase genes in germinating 14-day-old
spores was found as new mRNAs were
synthesized prior to activation of germination.
As a consequence, a delay in germination was
clearly observed. This study confirms a
significant role of GLA during germination of
M. rouxii which may be used as a target for
germination inhibition. Knowledge gained here
can serve as a basis for new drug design to
inhibit fungal infestation applicable to both
medical and agricultural purposes.
NC-354 OPTIMIZATION FOR PRODUCTION
L(+)-LACTIC ACID FROM Lactococcus lactis
IO-1
National Conference