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Fulltext A New Model of Alcoholic Fermentation under a Byproduct Inhibitory Effect

Zentou H, Zainal Abidin Z, Yunus R, Awang Biak DR, Abdullah Issa M, Yahaya Pudza M

ACS Omega, 2021 Feb 16;6(6):4137-4146.
PMID: 33644536 DOI: 10.1021/acsomega.0c04025

Despite the advantages of continuous fermentation whereby ethanol is selectively removed from the fermenting broth to reduce the end-product inhibition, this process can concentrate minor secondary products to the point where they become toxic to the yeast. This study aims to develop a new mathematical model do describe the inhibitory effect of byproducts on alcoholic fermentation including glycerol, lactic acid, acetic acid, and succinic acid, which were reported as major byproducts during batch alcoholic fermentation. The accumulation of these byproducts during the different stages of batch fermentation has been quantified. The yields of total byproducts, glycerol, acetic acid, and succinic acid per gram of glucose were 0.0442, 0.023, 0.0155, and 0.0054, respectively. It was found that the concentration of these byproducts linearly increases with the increase in glucose concentration in the range of 25-250 g/L. The results have also showed that byproduct concentration has a significant inhibitory effect on specific growth coefficient (μ) whereas no effect was observed on the half-velocity constant (Ks). A new mathematical model of alcoholic fermentation was developed considering the byproduct inhibitory effect, which showed a good performance and more accuracy compared to the classical Monod model.

Matched MeSH terms: Lactic Acid
Fulltext Fabrication and Characterization of Novel Poly(D-lactic acid) Nanocomposite Membrane for Water Filtration Purpose

Kian LK, Jawaid M, Alamery S, Vaseashta A

Nanomaterials (Basel), 2021 Jan 20;11(2).
PMID: 33498162 DOI: 10.3390/nano11020255

The development of membrane technology from biopolymer for water filtration has received a great deal of attention from researchers and scientists, owing to the growing awareness of environmental protection. The present investigation is aimed at producing poly(D-lactic acid) (PDLA) membranes, incorporated with nanocrystalline cellulose (NCC) and cellulose nanowhisker (CNW) at different loadings of 1 wt.% (PDNC-I, PDNW-I) and 2 wt.% (PDNC-II PDNW-II). From morphological characterization, it was evident that the nanocellulose particles induced pore formation within structure of the membrane. Furthermore, the greater surface reactivity of CNW particles facilitates in enhancing the surface wettability of membranes due to increased hydrophilicity. In addition, both thermal and mechanical properties for all nanocellulose filled membranes under investigation demonstrated significant improvement, particularly for PDNW-I-based membranes, which showed improvement in both aspects. The membrane of PDNW-I presented water permeability of 41.92 L/m2h, when applied under a pressure range of 0.1-0.5 MPa. The investigation clearly demonstrates that CNWs-filled PDLA membranes fabricated for this investigation have a very high potential to be utilized for water filtration purpose in the future.

Matched MeSH terms: Lactic Acid
Fulltext Supplementation of 100% Flesh Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] Juice Improves Swimming Performance in Rats

Ridwan R, Razak HRA, Adenan MI, Saad WMM

Prev Nutr Food Sci, 2019 Mar;24(1):41-48.
PMID: 31008095 DOI: 10.3746/pnf.2019.24.1.41

Nutritional intervention of fruit juice supplementation is able to maximize exercise performance. Watermelon [Citrullus lanatus (Thunb.) Matsum. and Nakai] contains high L-citrulline content and consumption of watermelon juice may promote ergogenic effects. The aim of the present study was to investigate the role of 100% flesh watermelon juice and 100% rind watermelon juice supplementation for 14 days on swimming performance in rats. Twenty four male Sprague-Dawley rats were randomly divided into four groups: Cx group of rats supplemented with filtered tap water (negative control), L-cit group of rats supplemented with L-citrulline (positive control), FR group of rats supplemented with 100% flesh watermelon juice, and RR group of rats supplemented with 100% rind watermelon juice. Each group was supplemented for 14 days ad libitum prior to swimming exercise protocol. The rats were performed swimming exercise for 3 days and swimming time until exhaustion was measured. Plasma samples were collected to measure lactate concentration, ammonia concentration, and nitric oxide production. Rats supplemented with 100% flesh watermelon juice demonstrated significantly prolonged of swimming time until exhaustion, reduction of lactate and ammonia concentrations, and increased of nitric oxide production compared to Cx and L-cit groups (P<0.05). These findings postulate that supplementation with 100% flesh watermelon juice improves endurance in swimming performance.

Matched MeSH terms: Lactic Acid
Antiglycolytic Activities of Strobilanthes crispus Active Fraction and its Bioactive Components on Triple-Negative Breast Cancer Cells In Vitro

Muhammad SNH, Yaacob NS, Safuwan NAM, Fauzi AN

Anticancer Agents Med Chem, 2021 Apr 26.
PMID: 33906591 DOI: 10.2174/1871520621666210427104804

BACKGROUND: Survival and progression of cancer cells are highly dependent on aerobic glycolysis. Strobilanthes crispus has been shown to have promising anticancer effects on breast cancer cells. The involvement of the glycolysis pathway in producing these effects is unconfirmed, thus further investigation is required to elucidate this phenomenon.
OBJECTIVE: This study aims to determine the effect of S. crispus active fraction (F3) and its bioactive components on glycolysis in triple-negative breast cancer cells (MDA-MB-231).
METHODS: This study utilizes F3, lutein, β-sitosterol, and stigmasterol to be administered in MDA-MB-231 cells for measurement of antiglycolytic activities through cell poliferation, glucose uptake, and lactate concentration assays. Cell proliferation was assessed by MTT assay of MDA-MB-231 cells after treatment with F3 and its bioactive components lutein, β-sitosterol, and stigmasterol. The IC50 value in each compound was determined by MTT assay to be used in subsequent assays. The determination of glucose uptake activity and lactate concentration were quantified using fluorescence spectrophotometry.
RESULTS: Antiproliferative activities were observed for F3 and its bioactive components, with IC50 values of 100 µg/mL (F3), 20 µM (lutein), 25 µM (β-sitosterol), and 90 μM (stigmasterol) in MDA-MB-231 cells at 48 h. The percentage of glucose uptake and lactate concentration in MDA-MB-231 cells treated with F3, lutein, or β sitosterol were significantly lower than those observed in the untreated cells in a time-dependent manner. However, treatment with stigmasterol decreased the concentration of lactate without affecting the glucose uptake in MDA-MB-231 cells.
CONCLUSION: The antiglycolytic activities of F3 on MDA-MB-231 cells are attributed to its bioactive components.

Matched MeSH terms: Lactic Acid
Fulltext Insights into the Role of microRNAs in Colorectal Cancer (CRC) Metabolism

Wai Hon K, Zainal Abidin SA, Othman I, Naidu R

Cancers (Basel), 2020 Aug 31;12(9).
PMID: 32878019 DOI: 10.3390/cancers12092462

Colorectal cancer (CRC) is one of the most frequently diagnosed cancers, with a high mortality rate globally. The pathophysiology of CRC is mainly initiated by alteration in gene expression, leading to dysregulation in multiple signalling pathways and cellular processes. Metabolic reprogramming is one of the important cancer hallmarks in CRC, which involves the adaptive changes in tumour cell metabolism to sustain the high energy requirements for rapid cell proliferation. There are several mechanisms in the metabolic reprogramming of cancer cells, such as aerobic glycolysis, oxidative phosphorylation, lactate and fatty acids metabolism. MicroRNAs (miRNAs) are a class of non-coding RNAs that are responsible for post-transcriptional regulation of gene expression. Differential expression of miRNAs has been shown to play an important role in different aspects of tumorigenesis, such as proliferation, apoptosis, and drug resistance, as well as metabolic reprogramming. Increasing evidence also reports that miRNAs could function as potential regulators of metabolic reprogramming in CRC cells. This review provides an insight into the role of different miRNAs in regulating the metabolism of CRC cells as well as to discuss the potential role of miRNAs as biomarkers or therapeutic targets in CRC tumour metabolism.

Matched MeSH terms: Lactic Acid
Fulltext Physicochemical properties of rambutan (Nephelium lappaceum L.) seed during natural fermentation of the whole peeled fruit

Chai, K. F., Adzahan, N. M., Karim, R., Rukayadi, Y., Ghazali, H. M.

International Food Research Journal, 2020;27(3):397-407.
MyJurnal

A novel way to reduce rambutan wastage is to ferment the fruit and valorise the seed post-fer- mentation into other food products and ingredients. Hence, the objective of this study was to investigate the physicochemical properties of rambutan seed during solid-state fermentation of the fruit. Peeled rambutan fruits were subjected to natural fermentation for ten days at 30°C. The environmental temperature, relative humidity, internal and external temperatures of the fermentation mass were measured daily. After ten days of fermentation, the seeds had higher cut test score (867.5), fermentation index (1.527), and a* value (8.20 for non-dried seeds and
9.93 for dried seeds), and lower L* (51.90 for non-dried seeds and 49.22 for dried seeds) and b* (30.52 for non-dried seeds and 30.12 for dried seeds) values; as compared to the non-fer- mented seeds (cut test score, 0.0; fermentation index, 0.856; L*, a*, and b* values, 64.52, 2.25, and 42.07 for non-dried seeds, respectively, and 61.03, 3.23 and 36.70 for dried seeds, respectively). During this time, pH, total soluble solids, fructose, glucose, sucrose, citric acid, and tartaric acid contents of the seeds decreased by 46, 44, 59, 61, 100, 85, and 100%, respec- tively, while the titratable acidity, lactic acid, acetic acid, and ascorbic acid contents of the seeds increased by 5.5, 7.8, 6.0, and 2.2-fold, respectively. Results showed that eight days of fermentation are adequate to produce well-fermented rambutan seeds that could be further processed into a cocoa powder-like product by roasting the fermented fruits in a manner similar to that of cocoa bean roasting.

Matched MeSH terms: Lactic Acid
In vitro and in vivo evaluation of drug-eluting microspheres designed for transarterial chemoembolization therapy

Wang Y, Molin DG, Sevrin C, Grandfils C, van den Akker NM, Gagliardi M, et al.

Int J Pharm, 2016 Apr 30;503(1-2):150-62.
PMID: 26965198 DOI: 10.1016/j.ijpharm.2016.03.002

Poly(d,l-lactic acid) biodegradable microspheres, loaded with the drugs cisplatin and/or sorafenib tosylate, were prepared, characterized and studied. Degradation of the microspheres, and release of cisplatin and/or sorafenib tosylate from them, were investigated in detail. Incubation of the drug-carrying microspheres in phosphate buffered saline (pH=7.4) revealed slow degradation. Nevertheless, significant release of cisplatin and sorafenib tosylate from microspheres loaded with both drugs was apparent in vitro; this can be attributed to their porous structure. Supernatants from microspheres loaded with both drugs showed strong toxic effects on cells (i.e. endothelial cells, fibroblast cells and Renca tumor cells) and potent anti-angiogenic effect in the matrigel endothelial tube assay. In vivo anti-tumor effects of the microspheres were also observed, in a Renca tumor mouse model. The poly(d,l-lactic acid) microspheres containing both cisplatin and sorafenib tosylate revealed highest therapeutic efficacy, probably demonstrating that combined local administration of cisplatin and sorafenib tosylate synergistically inhibits tumor growth in situ. In conclusion, this study demonstrates the applicability of biodegradable poly(d,l-lactic acid) microspheres loaded with cisplatin and sorafenib tosylate for local drug delivery as well as the potential of these microspheres for future use in transarterial chemoembolization.

Matched MeSH terms: Lactic Acid
Fulltext Hartman's solution or normal saline in the treatment of hyperemesis gravidarum among South East Asian population: a randomised controlled trial

Adibah, I., Khursiah, D., Ahmad, A.I., Zaki, N.N.M.

International Medical Journal Malaysia, 2008;7(2):21-24.
MyJurnal

Introduction: The aim of treatment for hyperemesis gravidarum is to stop vomiting, correction of dehydration, starvation and electrolytes imbalance. The common types of fluid used for fluid replacement are isotonic solutions like normal saline and hartman's solutions. The absence of potassium in normal saline makes hartman's solution superior but there is a possibility that the lactate component in hartman's solution could worsen the starvation state of the patients. This study is to evaluate which of these two solutions is more effective for fluid replacement in hyperemesis gravidarum. The objectives are to compare which solution corrects dehydration, hypokalaemia and acetonuria faster and to evaluate whether the ketosis state is aggravated by lactate component in hartman's solution. Materials and Methods: Patients with hyperemesis gravidarum were randomised to receive either Hartman's solution or normal saline at the rate of 125mls/hour. Blood urea and serum electrolytes, haematocrit, lactate and urine acetone were taken during admission and repeated every 12 hours. The volume of fluid required to correct dehydration, hypokalaemia and acetonuria were compared. Comparison of the pre and post treatment level of serum lactate were also done. Results: Both hartman's solution and normal saline are both effective in correcting dehydration (11.52Â±3.28 pints versus 11.94 Â± 2.30pints respectively) and acetonuria (11.64 Â± 2.75 pints versus 11.64 Â± 2.54 pints respectively).
A lower volume of hartman's solution was needed to correct hypokalaemia (8.34 Â± 2.44 pints versus 8.88 Â± 2.63 pints) but was not statistically significant. Ketonaemia was not made worse after treatment with hartman's solution. Conclusion: Normal saline and hartman's solution are equally effective in treating complications of hyperemesis gravidarum.

Matched MeSH terms: Lactic Acid
Fulltext Microbiological quality of freshwater prawns during storage

Abu Bakar, F.

International Food Research Journal, 2008;15(3):258-272.
MyJurnal

Microbiological quality analysis of freshwater prawns from three sampling sites in Peninsular Malaysia viz: Site 1- Kg. Jumbang, Negri Sembilan; Site 2- Kg. Cangkat Tin, Perak and Site 3- Kg. Cenderiang, Perak for total mesophilic and psychrophilic aerobic counts, proteolytic bacterial counts, histamine producing bacteria, cadaverine producing bacteria and putrescine producing bacteria in the prawns and pond water for the three sites showed that the microbiological quality of freshwater prawns is related to the microflora of pond water in which they were grown. The initial bacterial counts indicated the values were in the range of log 4+ CFU/g for all samples. Total mesophilic and psychrophilic counts of the head regions were higher than that of the body regions for all prawn samples and types of growth media tested. All samples showed an increase in counts with time and temperature of storage up to log 7+ CFU/g for mesophilic counts after 12 hours at ambient, 6 days at 10 ± 2°C and 12 days at iced storage. The samples from Site 2 had relatively higher counts compared to the other two sites which correlated well with the levels determined in the pond water. Similar trends were observed for psychrophilic counts but at lower values for the different types of media studied.
Effects of preservatives on quality changes and shelf life of shrimp during iced storage indicated that boric acid, lactic acid and sodium metabisulphite managed to inhibit psychrophilic bacteria and biogenic amines formation in prawns while maintaining the mesophilic counts at lower levels during iced storage.

Matched MeSH terms: Lactic Acid
Fulltext The mechanical, thermal and morphological properties of graphene nanoplatelets filled poly(lactic acid)/epoxidized palm oil blends

Chieng, Buong Woei, Nor Azowa Ibrahim, Wan Md Zin Wan Yunus, Mohd Zobir Hussein

Scientific Research Journal, 2014;11(2):0-0.
MyJurnal

Poly(lactic acid) (PLA)-based nanocomposites filled with graphene nanoplatelets (xGnP) that contains epoxidized palm oil (EPO) as plasticizer were prepared by melt blending method. PLA was first plasticized by EPO to improve its flexibility and thereby overcome its problem of brittleness. Then, xGnP was incoporated into plasticized PLA to enhance its mechanical properties. Plasticized and nanofilled PLA nanocomposites (PLA/EPO/xGnP) showed improvement in the elongation at break by 3322% and 61% compared to pristine PLA and PLA/EPO, respectively. The use of EPO and xGnP increases the mobility of the polymeric chains, thereby improving the flexibility and plastic deformation of PLA. The nanocomposites also resulted in an increase of up to 26.5% in the tensile strength compared with PLA/EPO blend. XRD pattern showed the presence of peak around 26.5° in PLA/EPO/xGnP nanocomposites which corresponds to characteristic peak of graphene nanoplatelets. Plasticized PLA reinforced with xGnP showed that increasing the xGnP content triggers a substantial increase in thermal stability. Crystallinity of the nanocomposites as well as cold crystallization and melting temperature did not show any significant changes upon addition of xGnP. However, there was a significant decrease of glass transition temperature up to 0.3wt% of xGnP incorporation. The TEM micrograph of PLA/EPO/xGnP shows that the xGnP was uniformly dispersed in the PLA matrix and no obvious aggregation was observed.

Matched MeSH terms: Lactic Acid
Fulltext Effect of different beverages on the physical properties of sonicfill dental composite

KV, Lee, A, Philip, Yahya NA

Ann Dent, 2015;22(1):30-37.
MyJurnal

To evaluate the effect of several beverages on the physical properties of SonicFill (Kerr Corp.,
USA), a new bulk-fill dental composite, over a period of time. Methods: A total of 28 discs (10 mm x 2
mm) were prepared and randomly assigned into 4 groups (n=7) according to the beverages they would
be immersed in. The beverages chosen were Coca-Cola©, Nescafe© coffee, Lipton tea© and distilled
water (control). Surface roughness, microhardness and colour stability were evaluated using 3D optical
surface texture analyser, Vickers microhardness tester and spectrophotometer respectively. Readings
were recorded at the time intervals of 24 hours, 1 week and 1 moth after immersion. The data obtained
were analysed using one-way ANOVA, repeated measures ANOVA and MANOVA. Results: There were
significant differences in surface roughness for only two pairs of groups (distilled water and Coca-Cola,
distilled water and coffee). However, there was no significant difference between the groups within the
chosen time. Statistical analysis showed significant difference in microhardness between time only for
Coca-Cola, with significant differences between 24 hours and 1 week; and 24 hours and 1 month. For
the colour evaluation, there was significant difference between the groups within time. Conclusions:
All the beverages chosen were able to affect the physical properties of the SonicFill. However, no
particular beverage had a higher or lower impact on the surface roughness than the other beverages.
Microhardness was affected by distilled water and Coca-Cola, in ascending order. Colour was affected
most by coffee, followed by tea and Coca-Cola.

Matched MeSH terms: Lactic Acid
Fulltext Antibacterial efficacy of triple-layered poly(lactic-co-glycolic acid)/nanoapatite/lauric acid guided bone regeneration membrane on periodontal bacteria

Saarani NN, Jamuna-Thevi K, Shahab N, Hermawan H, Saidin S

Dent Mater J, 2017 May 31;36(3):260-265.
PMID: 28111388 DOI: 10.4012/dmj.2016-177

A guided bone regeneration (GBR) membrane has been extensively used in the repair and regeneration of damaged periodontal tissues. One of the main challenges of GBR restoration is bacterial colonization on the membrane, constitutes to premature membrane degradation. Therefore, the purpose of this study was to investigate the antibacterial efficacy of triple-layered GBR membrane composed of poly(lactic-co-glycolic acid) (PLGA), nanoapatite (NAp) and lauric acid (LA) with two types of Gram-negative periodontal bacteria, Fusobacterium nucleatum and Porphyromonas gingivalis through a disc diffusion and bacterial count tests. The membranes exhibited a pattern of growth inhibition and killing effect against both bacteria. The increase in LA concentration tended to increase the bactericidal activities which indicated by higher diameter of inhibition zone and higher antibacterial percentage. It is shown that the incorporation of LA into the GBR membrane has retarded the growth and proliferation of Gram-negative periodontal bacteria for the treatment of periodontal disease.

Matched MeSH terms: Lactic Acid
Fulltext True mechanical behaviour and the associated structure morphology of Poly(Lactid Acid) polymer in strain induced crystallisation by in-situ time resolved x-ray diffraction and scattering technique

Muhammad Rawi Mohamed Zin, Mahendrasingam, Arumugam, Konkel, Chris, Narayanan, Theyencheri

Jurnal Sains Nuklear Malaysia, 2011;23(2):53-59.
MyJurnal

Changes in molecular structure configuration during strain induced crystallisation of an amorphous Poly(Lactic Acid) (PLA 4032D) polymer was monitored in-situ by simultaneously recording the wide angle x-ray scattering (WAXS) and small angle x-ray scattering (SAXS) patterns together with polymer deformation images and force data. The amorphous chain orientation from the beginning of deformation until the onset of crystallisation was studied from the WAXS patterns. The true mechanical behaviour described by the true stress-true strain curve related to an amorphous chain orientation exhibited a linear behaviour. Approaching critical amorphous orientation, the true stress-true strain curve deviated from linear into non-linear behaviour. After the onset of crystallization, when the deformed polymer became a semicrystalline state, the true mechanical behaviour exhibited true strain hardening which greatly affected by the formation of the morphology. The gradual true strain hardening was associated with the formation of micro-fibrillar structure containing thin crystallite morphology whilst sharp increased in true strain hardening was associated with the formation of stacked lamellar morphology in the form of macro-lattice structure. The study was accomplished by the application of high brilliance synchrotron radiation at beamline ID2 of ESRF, Grenoble in France and the usage of the high contrast resolution of WAXS and SAXS charge-couple device (CCD) camera as well as 40 milliseconds temporal resolution of data acquisition system.

Matched MeSH terms: Lactic Acid
Fulltext The 28-day mortality prediction in sepsis patients using static lactate concentration and early lactate clearance: an observational study

Noor Asmidar, A., Tan, T.L., Ong, W.J., Ahmad Fuad Fahmi, M.N., Chieng, Z.L., Noor Akmal, S.I.

Medicine & Health, 2014;9(2):124-133.
MyJurnal

Sepsis causes high mortality and morbidity. Static lactate concentration and early lactate clearance are cited to be a predictor for sepsis survival. This study examined the clinical utility of static lactate concentration and early lactate clearance within the first six hours of admission in Emergency Department (ED) to predict 28-day mortality rate in sepsis patients. Patients who presented with sepsis, severe sepsis or septic shock and admitted to ED of Universiti Kebangsaan Malaysia Medical Centre were recruited. Blood lactate concentrations were measured upon admission (H0), at 1st hour (H1) and 6th hour (H6), respectively. Either standard treatment of sepsis or early goal directed therapy was initiated according to sepsis severity. A follow-up report was conducted at 28 days via telephone call, e-mail or case notes. Patients were later classified into survivor and non-survivor as final outcome. Static lactate concentration appeared to be significantly higher for non-survivor as compared to the survival group at H0, H1 and H6 (p

Matched MeSH terms: Lactic Acid
Fulltext Response of Streptococcus Zooepidemicus to oxidative stress in hyaluronic acid fermentation

Mashitah, M.D., Masitah, H., Ramachandran, K.B.

Pertanika Journal of Science & Technology, 2009;17(1):-.
MyJurnal

Streptococcus zooepidemicus (SZ) is an aerotolerant bacteria and its ability to survive under reactive oxidant raises the question of the existence of a defense system against oxidative stress. As a characteristic of lactic acid bacteria, Streptococcus lacks an ordinary anti-oxidative stress enzyme, catalases and an electron transport chain. Whether this bacterium resists oxidative stress prior to an exposure to a higher level of an oxidizing agent H2O2 in hyaluronic acid fermentation is not known. This paper describes that Streptococcus cells, once treated with lower concentrations of H2O2 (i.e. 0.25, 0.50 and 1.0 mM) at least, were prepared for a subsequent higher concentrations of H2O2 such as 20.5 and 100 mM. At low concentrations (i.e. 0.25, 0.50 and 1.0 mM), H2O2 was found to act as a stimulant for HA synthesis, but it became toxic if presented at a very high level (100 mM H2O2). The highest HA yield to glucose consumed (YHAtotal/glu) was 0.017 gg-1 for the cells pre-treated with 0 mM of H2O2, and then exposed to 20.5 mM H2O2. Thus, this implied that this bacteria might possess a defense mechanism against oxidative stress and that this system was inducible.

Matched MeSH terms: Lactic Acid
Fulltext Fatigue onset through oxidative stress, dehydration and lactic acid accumulation and its in vivo study using experimental animals

Hani Hafeeza Halim, Mohd Sabri Pak Dek, Azizah Abdul Hamid, Ahmad Haniff Jaafar

Journal of Advanced Review on Scientific Research, 2017;35(1):1-12.
MyJurnal

Among athletes, endurance is one of the key elements to victory. In addition to
training, athletes normally used supplement to prevent fatigue during the event. With
prolonged and intense activity, our body started to experience decrease in muscle
performance due to several factors such as oxidative stress, dehydration and
accumulation of lactic acid in the body fluids. The free radicals generated during
intense exercise will expose the cells to oxidative damages. In the event of
dehydration, there will be significant losses of water and functional electrolytes during
intense exercise which affected the body fluid balance. Fatigue will also occur during
reduced oxygen in aerobic metabolism which later caused accumulation of lactic acid
in the muscle. This will change the pH balance toward more acidic and caused the
muscles to lose contractile efficiency. In addition, fatigue can also be studied using rats
as model organism. Results from this activity can be useful to analyse cellular
metabolism and physiology effects of the tested rats toward physical exercise.
Therefore, this review aims to discuss the causes of fatigue through oxidative stress,
dehydration and lactic acid accumulation. In addition, the effectiveness of using rats as
a model system in measuring fatigue is also included in illustrating examples on fatigue
assessment in vivo.

Matched MeSH terms: Lactic Acid
Fulltext Docking Based 3D-QSAR Study of Tricyclic Guanidine Analogues of Batzelladine K As Anti-Malarial Agents

Ahmed N, Anwar S, Thet Htar T

Front Chem, 2017;5:36.
PMID: 28664157 DOI: 10.3389/fchem.2017.00036

The Plasmodium falciparum Lactate Dehydrogenase enzyme (PfLDH) catalyzes inter-conversion of pyruvate to lactate during glycolysis producing the energy required for parasitic growth. The PfLDH has been studied as a potential molecular target for development of anti-malarial agents. In an attempt to find the potent inhibitor of PfLDH, we have used Discovery studio to perform molecular docking in the active binding pocket of PfLDH by CDOCKER, followed by three-dimensional quantitative structure-activity relationship (3D-QSAR) studies of tricyclic guanidine batzelladine compounds, which were previously synthesized in our laboratory. Docking studies showed that there is a very strong correlation between in silico and in vitro results. Based on docking results, a highly predictive 3D-QSAR model was developed with q(2) of 0.516. The model has predicted r(2) of 0.91 showing that predicted IC50 values are in good agreement with experimental IC50 values. The results obtained from this study revealed the developed model can be used to design new anti-malarial compounds based on tricyclic guanidine derivatives and to predict activities of new inhibitors.

Matched MeSH terms: Lactic Acid
Incorporation of Human-Platelet-Derived Growth Factor-BB Encapsulated Poly(lactic-co-glycolic acid) Microspheres into 3D CORAGRAF Enhances Osteogenic Differentiation of Mesenchymal Stromal Cells

Mohan S, Raghavendran HB, Karunanithi P, Murali MR, Naveen SV, Talebian S, et al.

ACS Appl Mater Interfaces, 2017 Mar 22;9(11):9291-9303.
PMID: 28266827 DOI: 10.1021/acsami.6b13422

Tissue engineering aims to generate or facilitate regrowth or healing of damaged tissues by applying a combination of biomaterials, cells, and bioactive signaling molecules. In this regard, growth factors clearly play important roles in regulating cellular fate. However, uncontrolled release of growth factors has been demonstrated to produce severe side effects on the surrounding tissues. In this study, poly(lactic-co-glycolic acid) (PLGA) microspheres (MS) incorporated three-dimensional (3D) CORAGRAF scaffolds were engineered to achieve controlled release of platelet-derived growth factor-BB (PDGF-BB) for the differentiation of stem cells within the 3D polymer network. Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and microtomography were applied to characterize the fabricated scaffolds. In vitro study revealed that the CORAGRAF-PLGA-PDGF-BB scaffold system enhanced the release of PDGF-BB for the regulation of cell behavior. Stromal cell attachment, viability, release of osteogenic differentiation markers such as osteocalcin, and upregulation of osteogenic gene expression exhibited positive response. Overall, the developed scaffold system was noted to support rapid cell expansion and differentiation of stromal cells into osteogenic cells in vitro for bone tissue engineering applications.

Matched MeSH terms: Lactic Acid
Fulltext Effects of method and duration of restraint on stress hormones and meat quality in broiler chickens with different body weights

Ismail SN, Awad EA, Zulkifli I, Goh YM, Sazili AQ

Asian-Australas J Anim Sci, 2019 Jun;32(6):865-873.
PMID: 30381751 DOI: 10.5713/ajas.18.0354

OBJECTIVE: The study was designed to investigate the effects of restraint method, restraint duration, and body weight on stress-linked hormones (corticosterone, adrenaline, and noradrenaline), blood biochemical (namely glucose and lactate), and the meat quality in broiler chickens.
METHODS: A total of 120 male broiler chickens (Cobb 500) were assigned to a 2×3×2 factorial arrangement in a completely randomized design using two restraint methods (shackle and cone), three durations of restraint (10, 30, and 60 s), and two categories of live body weight (1.8±0.1 kg as lightweight and 2.8±0.1 kg as heavyweight).
RESULTS: Irrespective of the duration of restraint and body weight, the coned chickens were found to have lower plasma corticosterone (p<0.01), lactate (p<0.001), lower meat drip loss (p<0.01), cooking loss (p<0.05), and higher blood loss (p<0.05) compared with their shackled counterparts. The duration of restraint had significant effects on the meat initial pH (p<0.05), ultimate pH (p<0.05), and yellowness (p<0.01). The lightweight broilers exhibited higher (p< 0.001) blood loss and lower (p<0.05) cooking loss compared to the heavyweight broilers, regardless of the restraint method used and the duration of restraint. However, the interaction between the restraint method, duration of restraint, and body weight contributed to differences in pre-slaughter stress and meat quality. Therefore, the interaction between the restraint method and the duration of restraint affected the meat shear force, lightness (L*) and redness (a*).
CONCLUSION: The duration of restraint and body weight undoubtedly affect stress responses and meat quality of broiler chickens. Regardless of the duration of restraint and body weight, the cone restraint resulted in notably lower stress, lower meat water loss, and higher blood loss compared to shackling. Overall, the findings of this study showed that restraint method, duration of restraint, and body weight may affect the stress response and meat quality parameters in broilers and should be considered independently or interactively in future studies.

Matched MeSH terms: Lactic Acid
Fulltext Growth Enhancement of Probiotic Pediococcus acidilactici by Extractive Fermentation of Lactic Acid Exploiting Anion-Exchange Resin

Othman M, Ariff AB, Kapri MR, Rios-Solis L, Halim M

Front Microbiol, 2018;9:2554.
PMID: 30420842 DOI: 10.3389/fmicb.2018.02554

Fermentation employing lactic acid bacteria (LAB) often suffers end-product inhibition which reduces the cell growth rate and the production of metabolite. The utility of adsorbent resins for in situ lactic acid removal to enhance the cultivation performance of probiotic, Pediococcus acidilactici was studied. Weak base anion-exchange resin, Amberlite IRA 67 gave the highest maximum uptake capacity of lactic acid based on Langmuir adsorption isotherm (0.996 g lactic acid/g wet resin) compared to the other tested anion-exchange resins (Amberlite IRA 410, Amberlite IRA 400, Duolite A7 and Bowex MSA). The application of Amberlite IRA 67 improved the growth of P. acidilactici about 67 times compared to the control fermentation without resin addition. Nevertheless, the in situ addition of dispersed resin in the culture created shear stress by resins collision and caused direct shear force to the cells. The growth of P. acidilactici in the integrated bioreactor-internal column system containing anion-exchange resin was further improved by 1.4 times over that obtained in the bioreactor containing dispersed resin. The improvement of the P. acidilactici growth indicated that extractive fermentation using solid phase is an effective approach for reducing by-product inhibition and increasing product titer.

Matched MeSH terms: Lactic Acid

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