Displaying publications 41 - 60 of 118 in total

Abstract:
Sort:
  1. Efficacy of papain-based wound cleanser in promoting wound regeneration
    Ajlia SA, Majid FA, Suvik A, Effendy MA, Nouri HS
    Pak J Biol Sci, 2010 Jun 15;13(12):596-603.
    PMID: 21061910
    A new invention, papain-based wound cleanser is formulated by incorporating papain, a proteolytic enzyme extracted from Carica papaya into the formulation. This cleanser is invented to simplify the methods in wound management by combining wound cleansing and wound debridement using a single formulation. This study describes the preparation and preclinical study of papain-based wound cleanser in accelerating wound healing. In this study, papain-based wound cleanser was used to treat wound incision on Sprague-Dawley rats while distilled water and Betadine were used as negative and positive control. Twenty-seven clinically healthy white rats were randomly divided into three groups and treated accordingly until the 21st day post-incision. Wound reduction rates and histological analysis were obtained to asses the healing pattern. Rats treated with papain-based wound cleanser showed a progressive wound healing based on the wound reduction rates and histological analysis when compared with rats treated with distilled water and Betadine. Better collagen deposition and presence of skin organelles in rats treated with papain-based wound cleanser demonstrated its efficacy in promoting wound healing. In addition to its wound healing effect, papain-based wound cleanser is also integrated with antibacterial properties which make it a complete package for wound management. However, further studies should be carried out to ensure its safety for human usage.
  2. Enhancement of biodegradation of crude petroleum-oil in contaminated water by the addition of nitrogen sources
    Mukred AM, Hamid AA, Hamzah A, Yusoff WM
    Pak J Biol Sci, 2008 Sep 01;11(17):2122-7.
    PMID: 19266926
    Addition of nitrogen sources as supplementary nutrient into MSM medium to enhance biodegradation by stimulating the growth four isolates, Acinetobacter faecalis, Staphylococcus sp., Pseudomonas putida and Neisseria elongata isolated from petroleum contaminated groundwater, wastewater aeration pond and biopond at the oil refinery Terengganu Malaysia was investigated. The organic nitrogen sources tested not only supported growth but also enhances biodegradation of 1% Tapis crude oil. All four isolates showed good growth especially when peptone was employed as the organic nitrogen compared to growth in the basal medium. Gas chromatography showed that more then 91, 93, 94 and 95% degradation of total hydrocarbon was observed after 5 days of incubation by isolates Pseudomonas putida, Neisseria elongate, Acinetobacter faecalis and Staphylococcus sp., respectively.
  3. Eurycoma longifolia in Radix for the treatment of ethanol-induced gastric lesion in rats
    Qodriyah HM, Asmadi AY
    Pak J Biol Sci, 2013 Dec 01;16(23):1815-8.
    PMID: 24506055
    The effect of treatment with Radix on ethanol-induced gastric lesions was investigated. The main ingredient of Radix is Eurycoma longifolia. Twenty-four rats of the Sprague-Dawley species were randomly divided into four groups. Three groups were given 0.5 mL 100% ethanol orally. Another group was used as a control and was given only distilled water orally (control). After 6 h all the rats were fed with normal diet. One group that was administered with ethanol was only given distilled water orally (no treatment). Another two groups that were administered with ethanol were treated with oral Radix 0.128 mg g(-1) b.wt. (Radix) and oral ranitidine 21.4 mg kg(-1) b.wt. (Ranitidine), respectively. After one week, all the rats were fasted overnight and sacrificed. The stomach was isolated and examined for the presence and severity of gastric lesions. Measurements for malondialdehyde content and gastric acid concentration were also done. It is found that the ulcer index was lower in the Radix and ranitidine group compared to the no treatment group whereas in the control group there was no lesion. There was no difference in ulcer index between the Radix and ranitidine group. The gastric MDA content was significantly higher in all the groups that were induced with ethanol compared to the control group but no difference between all the ethanol-induced groups. There was no difference in the gastric acid concentration in all groups. Hence it is concluded that Eurycoma longifolia in Radix is as effective as ranitidine in the treatment of ethanol-induced gastric lesions in rats.
  4. Evaluating ligand-receptor networks of TGF-beta with membrane computing
    Muniyandi RC, Zin AM
    Pak J Biol Sci, 2011 Dec 15;14(24):1100-8.
    PMID: 22335049
    Ligand-Receptor Networks of TGF-beta plays essential role in transmitting a wide range of extracellular signals that affect many cellular processes such as cell growth. However, the modeling of these networks with conventional approach such as ordinary differential equations has not taken into account, the spatial structure and stochastic behavior of processes involve in these networks. Membrane computing as the alternatives approach provides spatial structure for molecular computation in which processes are evaluated in a non-deterministic and maximally parallel way. This study is carried out to evaluate the membrane computing model of Ligand-Receptor Networks of TGF-beta with model checking approach. The results show that membrane computing model has sustained the behaviors and properties of Ligand-Receptor Networks of TGF-beta. This reinforce that membrane computing is capable in analyzing processes and behaviors in hierarchical structure of cell such as Ligand-Receptor Networks of TGF-beta better than the deterministic approach of conventional mathematical models.
  5. Fecundity, embryonic and ovarian development of blue swimming crab, Portunus pelagicus (Linnaeus, 1758) in coastal water of Johor, Malaysia
    Ikhwanuddin M, Azra MN, Siti-Aimuni H, Abol-Munafi AB
    Pak J Biol Sci, 2012 Aug 01;15(15):720-8.
    PMID: 24171257
    Blue swimming crab, Portunus pelagicus is widely study and research throughout the Indo-West Pacific, but little is known of its reproductive biology in Malaysia. The present study describes the fecundity, embryonic development and ovarian development stages of the P. pelagicus from Johor coastal water, Malaysia. Carapace width range of berried crabs sampled was from 9.64 to 13.32 cm, while the body weight range was from 75 to 235 g. The mean number of egg produced by females in different sizes ranged from 105443.333 +/- 35448.075 per eggs batch. Mean egg size during embryonic development at stage 1 was 0.307 +/- 0.037, while 0.386 +/- 0.039 and 0.396 +/- 0.033 for stage 2 and stage 3, respectively. Study showed that there was significant (p < 0.05) relationship between the number of eggs and carapace width/body weight. Mean diameter oocyte during ovarian development at stage 1 was 97.732 +/- 12.391 while for stage 2 was 149.516 +/- 23.287. Stage 3 showed increasingly of size with mean diameter was 158.506 +/- 27.616 and 181.013 +/- 24.339 for stage 4.
  6. Flashing light as growth stimulant in cultivation of green microalgae, Chlorella sp. utilizing airlift photobioreactor
    Fathurrahman L, Hajar AH, Sakinah DW, Nurhazwani Z, Ahmad J
    Pak J Biol Sci, 2013 Nov 15;16(22):1517-23.
    PMID: 24511694
    One of the main limitations of productivity in photobioreactor is the inefficient conversion of the available light into biomass. Photoautotrophic cells such as microalgae only absorb a small fraction of supplied illumination due to limitation of its photosystem's (PS) absorbing rate. However, phenomenon of Flashing Light Effect (FLE) allows microalgae to utilize strong light exceptionally through intermittent exposure. Exposure of strong light at correct frequency of light and dark photoperiod would allow two pigment-protein complexes, PSI and PSII to be at the equilibrium mid-point potential to allow efficient light conversion. Narrow range of optimum frequency is crucial since overexposure to strong light would injured photosynthetic apparatus whereas longer dark period would contributed to loss of biomass due to triacylglycerol metabolism. The behaviour of microalgae towards various illumination conditions of FLE was determined at batch Photobioreactor (PBR) by varying the aeration flow rate: 16.94, 33.14 and 49.28 mL sec(-1) which yield, respectively the light exposure time of 3.99, 1.71 and 1.1 seconds per cycle. Maximum cell density in FLE-PBR was significantly higher at the exponential phase as compared to the continuously illuminated culture (p = 5.62 x 10(-5), a = 0.05) under the flow rate of 25.07 mL sec(-1). Maximum cell density yield of FLE-PBR and continuously illuminated PBR was, respectively 3.1125 x 10(7) and 2.947 x 10(7) cells mL(-1). Utilization of FLE as an innovative solution to increase the efficiency of microalgae to convert light into chemical energy would revolutionize the microalgae culture, reduce the time for cultivation and produce higher maximum biomass density.
  7. Flow properties of ice cream mix prepared from palm oil: anhydrous milk fat blends
    Rosnani AI, Aini IN, Yazid AM, Dzulkifly MH
    Pak J Biol Sci, 2007 May 15;10(10):1691-6.
    PMID: 19086519
    Ice cream mixes containing 33.4% total solids including 10% fat, 11.1% milk solid-non fat (MSNF), 12% sugar, 0.35% commercial blend of emulsifier/ stabiliser and water were produced. The blending of PO with AMF were conducted at three different ratios 30: 70, 50: 50 and 70: 30, respectively. The experimental ice cream mixes were compared with a control ice cream mix prepared from AMF. The flow properties were measured after ageing at 0, 1, 1.5, 2 and 24 h and determined using a controlled stress rheometer (Haake RS 100). The Power Law and Casson equation was employed to estimate the yield stress of an ice cream mixes. The regression coefficients (r) was represented well by the Casson model (r > 0.99) for all the samples, indicating goodness of fit. The profiles of the consistency coefficients (K(c)) were quite similar for all experimental samples, which could be attributed to the fact that all the samples exhibited similar viscoelastic behaviour. The flow behaviour index (n) of an ice cream mix prepared from PO and their blends with AMF were less then 1.0 (range 0.04-0.08) indicating that they were psuedoplastic fluid. The eta(o) at shear rate 20(-1) indicated higher degree of viscosity in AMF.
  8. Frying performance of palm-based solid frying shortening
    Omar MN, Nor-Nazuha MN, Nor-Dalilah MN, Sahri MM
    Pak J Biol Sci, 2010 Mar 15;13(6):298-302.
    PMID: 20506718
    In order to evaluate the frying performance of palm-based solid frying shortening against standard olein, the fresh potato chips were fried in both frying media using an open fryer. After frying the chips for 40 h in an open batch fryer, it was found that the frying quality of palm-based solid frying shortening was better than standard palm olein in terms of Free Fatty Acid (FFA) values, Total Polar Content (TPC) and Total Polymeric Material (TPM). Solid shortening gave FFA, TPC and TPM values of 0.7, 15.3 and 2.67%, respectively, whilst standard palm olein gave values for FFA, TPC and TPM of 1.2, 19.6 and 3.10%, respectively. In terms of sensory mean scores, sensory panelists preferred the color of potato chips fried in solid shortening on the first day of frying, while on the third and fifth day of frying there were no significant differences (p < 0.05) in the sensory scores of fried products in both frying mediums. However, on the fifth day of frying, panelists gave higher scores in terms of taste, flavor and crispness for potato chips fried in solid shortening. These findings show that the palm-based solid shortening is better than palm olein when used for deep fat frying in terms of FFA values, total polar content and total polymeric material, especially for starch-based products such as potato chips. The result also shows that, in terms of sensory mean scores, after frying for 40 h, the sensory panelists gave higher scores in terms of taste, flavor and crispiness for potato chips fried in palm-based solid shortening.
  9. Germination and seedling development of Trapa bispinosa Roxb
    Mirani OI, Harah ZM, Sidik BJ
    Pak J Biol Sci, 2012 Jul 01;15(13):653-7.
    PMID: 24218936
    Trapa bispinosa is a freshwater macrophyte occurring in stagnant or slow moving water streams. Information on assessment of seeds storage and germination of Trapa bispinosa is less available in literature. Dependence on fresh seeds abundance only from natural environment for plant propagation or cultivation may lead to insufficient supply of seeds due to various biotic and abiotic factors. This study evaluated the viability and germination of Trapa bispinosa seeds stored in zip-lock plastic bag at low temperature of 7 degrees C for six months and fresh seeds. In addition germinating seeds progressive development to juvenile plants was recorded and described. Experiments were conducted where stored and fresh seeds were soaked in 62 x 45 x 54 cm glass tanks filled with aged tap water to the level of 15 cm depth. Stored seeds showed low percentage germination of 2.82% compared to fresh seeds which was 71.19%. Eight distinct developmental stages were identified from germinating seeds to juvenile plants. Both stored and fresh seeds produced plants of similar morphology but stored seeds progressive development from germination, seedling to juvenile plants needed longer duration to achieve. The storage of seed at low temperature at 7 degrees C for six months showed reduced viability and also vigorousity. Improved methods should be developed for Trapa seeds storage taking into account of the seeds' endurance to dryness and moisture levels in order to maintained seeds viability for future uses either for production, research purposes or even conservation and restoration programs.
  10. Growth enhancement of effective microorganisms for bioremediation of crude oil contaminated waters
    Mukred AM, Abd-Hamid A, Hamzah A, Yusoff WM
    Pak J Biol Sci, 2008 Jul 01;11(13):1708-12.
    PMID: 18819623
    The bioremediation of polluted groundwater, wastewater aeration pond and biopond sites was investigated using bacteria isolated from these sites located at the oil refinery Terengganu Malaysia. Out of 62 isolates, only 16 isolates from groundwater (8) and wastewater aeration pond (3) and biopond (5) were chosen based on growth medium containing 1% (v/v) Tapis crude oil. Only four isolates; Acinetobacter faecalis, Staphylococcus sp., Pseudomonas putida and Neisseria elongata showed percentage biodegradation of crude oil more than 50% after 5 days using Mineral Salts Medium (MSM). The effect of physical parameters (temperature, pH and agitation) on growth by all four strains showed a maximum growth in MSM medium with 1% Tapis crude oil at 37 degrees C with pH 7 and agitation of 130 rpm.
  11. Growth optimization and organogenesis of Gerbera jamesonii Bolus ex. Hook f. in vitro
    Hasbullah NA, Taha RM, Awal A
    Pak J Biol Sci, 2008 Jun 01;11(11):1449-54.
    PMID: 18817245
    Regeneration potentials in Gerbera jamesonii Bolus ex. Hook f. from tissues culture system was studied using leaf, petiole and root explants. In vitro regeneration, callus induction and root formation were optimized by manipulation of growth regulators during organogenesis. Various kinds of plant growth regulators such as 6-Benzylaminopurine (BAP), alpha-Naphthalene acetic acid (NAA), 2, 4-Dichlorophenoxyacetic acid (2,4-D), Indole-3-acetic acid (IAA), Indole-3-Butyric acid (IBA), N6-[2-Isopentenyl]adenine (2iP), Kinetin and Zeatin were used to initiate cultures. These plant growth regulators were added to Murashige and Skoog medium in different combinations and concentrations. Adventitious shoots were obtained from petiole explants cultured on Murashige and Skoog (MS) medium supplemented with 2.0 mg L(-1) BAP and 0.5 mg L(-1) NAA. Effectiveness of shoot regeneration medium, type of growth regulator used and duration of induction period were investigated. Leaf explants cultured on MS medium supplemented with 1.0 mg L(-1) BAP and 2.0 mg L(-1) 2, 4-D showed the best results for callus induction. Root explants were found to be non-regenerative in all experiments conducted. Petiole segment was identified as the best explant for regeneration of this species. Regenerated plants were rooted on Murashige and Skoog basal medium. Plantlets were then transferred to field with 75% survival rate.
  12. Heavy metals concentration relationship with Perna viridis physical properties in Mengkabong Lagoon, Sabah, Malaysia
    Abdullah N, Tair R, Abdullah MH
    Pak J Biol Sci, 2014 Jan 01;17(1):62-7.
    PMID: 24783779
    Perna viridis (P. viridis) has been identified as a good biological indicator in identifying environmental pollution, especially when there are various types of Heavy Metals Accumulations (HMA) inside its tissue. Based on the potential of P. viridis to accumulate heavy metals and the data on its physical properties, this study proffers to determine the relationships between both properties. The similarities of the physical properties are used to mathematical model their relationships, which included the size (length, width, height) and weight (wet and dry) of P. viridis, whilst the heavy metals are focused on concentrations of Pb, Cu, Cr, Cd and Zn. The concentrations of metal elements are detected by using Flame Atomic Adsorption Spectrometry. Results show that the mean concentration of Pb, Cu, Cr, Cd, Zn, length, width, height, wet weight and dry weight are: 1.12 +/- 1.00, 2.36 +/- 1.65, 2.12 +/- 2.74, 0.44 +/- 0.41 and 16.52 +/- 10.64 mg kg(-1) (dry weight), 105.08 +/- 14.35, 41.64 +/- 4.64, 28.75 +/- 3.92 mm, 14.56 +/- 3.30 and 2.37 +/- 0.86 g, respectively. It is also found out that the relationships between the Heavy Metals Concentrations (HMA) and the physical properties can be represented using Multiple Linear Regressions (MLR) models, relating that the HMA of Zinc has affected significantly the physical growth properties of P. viridis.
  13. Histological Characteristics on the Testes of Mud Spiny Lobster, Panulirus polyphagus (Herbst, 1793)
    Nor Fatihah S, Muhd-Farouk H, Amin-Safwan A, Hafiz Mahsol H, Ikhwanuddin M
    Pak J Biol Sci, 2017;20(7):365-371.
    PMID: 29023069 DOI: 10.3923/pjbs.2017.365.371
    BACKGROUND AND OBJECTIVE: Mud spiny lobsters, Panulirus polyphagus (P. polyphagus) are one of the most important fisheries resources now-a-days due to quality that it's possessed. However, there is still lack of in-depth study about this species mainly on males testicular characteristics and sexual maturity size. Therefore, the present study was carried out to investigate the histological characteristics on the testes and sexual maturity sizes of mud spiny lobster, Panulirus polyphagus.

    MATERIALS AND METHODS: The testes were dissected out and fixed in 10% buffered formalin solution for 11 h, dehydrated in 70% alcohol and lastly placed in tissue processor for 18±1 h at 60°C. The tissues blocks were cut at the thickness of 4 μm on a rotary microtome. Stained tissues were taken under Advance Microscope (Nikon Eclipse 80i Nomarski DIC). Collected data were analyzed using Microsoft Excel 2013. Data were presented as mean±standard deviation. Statistical analyses were done using one-way ANOVA using SPSS (Version 22).

    RESULTS: These lobules of mature P. polyphagus were formed via different germinative lineage cells such as spermatogonia, spermatocytes, spermatids and spermatozoa. The histological characteristics of testes showed that the process of spermatogenesis went through the stages of four testes maturation which were spermatogonia I and II, spermatocytes I and II, spermatids and spermatozoa stages within different body weight of P. polyphagus. It was found that there were significant difference between body weight and carapace length to the testicular maturation stages (one-way ANOVA and p = 0.000).

    CONCLUSION: The results of this experiment indicated that males P. polyphagus have four stages of testes maturation and can be considered to have fully mature testes that ready for fertilization at 452 g body weight (BW) and 107 mm carapace length (CL) or more.

  14. Horseshoe crab, Tachypleus gigas (Müller, 1785) spawning population at Balok Beach, Kuantan, Pahang, Malaysia
    Tan AN, Christianus A, Shakibazadeh S, Hajeb P
    Pak J Biol Sci, 2012 Jul 01;15(13):610-20.
    PMID: 24218930
    Local and regional decline of Asian horseshoe crabs has spurred a study on its spawning population at Balok Beach, Kuantan, Pahang, Malaysia. This location was identified as spawning site due to the occurrence of horseshoe crab spawning pairs and nests. Size-frequency, length-weight relationships, sex ratio and epibiont infestation of Tachypleus gigas were studied. Instar stage was estimated based on prosomal width. Condition of the horseshoe crab carapace was reported. Visual search technique of horseshoe crab was conducted during high tide of new and full moons. Prosomal, opisthosomal and telson length and weight of each horseshoe crab were measured. Largest female was recorded with mean prosomal length and width of 154.4 and 246.9 mm, respectively. About 69.8% of the males belonged to size group of 151-200 mm and 53.3% of females were grouped into 201-250 mm. All individuals were of fourteenth to sixteenth instar stages. Sex ratio varied from 0.313 to 2.5 and attributed to commercial harvest and monsoon season. Sand sediment of study site showed 93% of fine sands with grain size ranged from 120 to 250 microm. Acorn and pedunculate barnacle, conical and flat slipper shells were found on the carapace of the specimens. Most males had damaged eyes and carapaces while females with broken telsons. Body damages of about 19.9% on the specimens were likely due to nearby fishing activities. Lack of satellite male indicated low spawning population. The finding of this study showed that the species is extremely threatened by human activities and coastal development.
  15. Immobilised Sarawak Malaysia yeast cells for production of bioethanol
    Zain MM, Kofli NT, Rozaimah S, Abdullah S
    Pak J Biol Sci, 2011 May 01;14(9):526-32.
    PMID: 22032081
    Bioethanol production using yeast has become a popular topic due to worrying depleting worldwide fuel reserve. The aim of the study was to investigate the capability of Malaysia yeast strains isolated from starter culture used in traditional fermented food and alcoholic beverages in producing Bioethanol using alginate beads entrapment method. The starter yeast consists of groups of microbes, thus the yeasts were grown in Sabouraud agar to obtain single colony called ST1 (tuak) and ST3 (tapai). The growth in Yeast Potatoes Dextrose (YPD) resulted in specific growth of ST1 at micro = 0.396 h-1 and ST3 at micro = 0.38 h-1, with maximum ethanol production of 7.36 g L-1 observed using ST1 strain. The two strains were then immobilized using calcium alginate entrapment method producing average alginate beads size of 0.51 cm and were grown in different substrates; YPD medium and Local Brown Sugar (LBS) for 8 h in flask. The maximum ethanol concentration measured after 7 h were at 6.63 and 6.59 g L-1 in YPD media and 1.54 and 1.39 g L-1in LBS media for ST1 and ST3, respectively. The use of LBS as carbon source showed higher yield of product (Yp/s), 0.59 g g-1 compared to YPD, 0.25 g g-1 in ST1 and (Yp/s), 0.54 g g-1 compared to YPD, 0.24 g g-1 in ST3 . This study indicated the possibility of using local strains (STI and ST3) to produce bioethanol via immobilization technique with local materials as substrate.
  16. In vitro anti-oxidant and anti-cancer activity of methanolic extract from Sanchezia speciosa leaves
    Paydar M, Wong YL, Moharam BA, Wong WF, Looi CY
    Pak J Biol Sci, 2013 Oct 15;16(20):1212-5.
    PMID: 24506026
    Sanchezia speciosa, is a bushy shrub from Acanthaceae family which commonly grows in tropical areas of South and Central America. In this study, we employed MTT assay to test the cytotoxicity of that methanolic fraction of S. speciosa leaves on MCF-7 human breast cancer, SK-MEL-5 human malignant melanoma and human umbilical vein endothelial cells, HUVEC cells. The extract showed highest activity on MCF-7 and moderate cytotoxicity towards SK-MEL-5. In contrast, the extract demonstrated lowest cell growth inhibition activity on HUVEC cells, indicating better selectivity compare to standard drug, doxorubicin. In addition, we also performed ORAC assay to determine the radical scavenging capacity of methanolic extract of S. speciosa leaves. The extract exhibited nearly similar anti-oxidant activity as quercetin, suggesting S. speciosa leaves as a potential source of natural anti-oxidant. To the best of our knowledge, this is the first report on anti-oxidant and cytotoxic activity of S. speciosa.
  17. Investigation of biogas production and its residue with fertilization effect from municipal waste
    Bee ST, Nithiyaa M, Sin LT, Tee TT, Rahmat AR
    Pak J Biol Sci, 2013 Oct 15;16(20):1104-12.
    PMID: 24506009
    This study was aimed to investigate the production of methane gas from three different types of food waste (vegetables waste, fruit waste and grain waste) using batch type anaerobic digestion method. The digestion process was conducted by using temperature range of 27 to 36 degrees C and pH 6.5 to 7.5 to yield an optimum condition for the digestion process. The digestion was continued for a period of two weeks with the aid of cow dung as the inoculums. It was found that the grain waste yielded the highest methane 2546 mL due to the high content of carbohydrate. At the mean time, the fruit waste produced the second highest methane gas with 2000 mL as well as the vegetable waste generated the lowest methane gas with volume of 1468 mL. The vegetable waste produced the lowest methane gas because the vegetables waste contains high fibres and cellulose walls but low in glucose amount. For the fertilization test, fruit waste demonstrated the best observation for the growth of plant due to high content of potassium and followed by vegetable waste. The least effective fertilizer was grain waste due to less content of nutrients essential for plants growth.
  18. Isolation of Potential Bacteria as Inoculum for Biofloc Formation in Pacific Whiteleg Shrimp, Litopenaeus vannamei Culture Ponds
    Kasan NA, Ghazali NA, Ikhwanuddin M, Ibrahim Z
    Pak J Biol Sci, 2017;20(6):306-313.
    PMID: 29023055 DOI: 10.3923/pjbs.2017.306.313
    BACKGROUND AND OBJECTIVE: A new green technology to reduce environmental damages while optimizing production of Pacific Whiteleg shrimp, Litopenaeus vannamei was developed known as "Biofloc technology". Microbial communities in biofloc aggregates are responsible in eliminating water exchange and producing microbial proteins that can be used as supplemented feed for L. vannamei. This study aimed to isolate and identify potential bioflocculant-producing bacteria to be used as inoculum for rapid formation of biofloc.

    MATERIALS AND METHODS: For the purpose of this study, bacterial communities during 0, 30 and 70 days of culture (DOC) of L. vannamei grow-out ponds were isolated and identified through phenotypic and 16S rDNA sequences analysis. Phylogenetic relationships between isolated bacteria were then evaluated through phylogenetic tree analysis. One-way analysis of variance (ANOVA) was used to compare the differences of microbial communities at each DOC.

    RESULTS: Out of 125 bacterial isolates, nine species of bacteria from biofloc were identified successfully. Those bacteria species were identified as Halomonas venusta, H. aquamarina, Vibrio parahaemolyticus, Bacillus infantis, B. cereus, B. safensis, Providencia vermicola, Nitratireductor aquimarinus and Pseudoalteromonas sp., respectively. Through phylogenetic analysis, these isolates belong to Proteobacteria and Firmicutes families under the genera of Halomonas sp., Vibrio sp., Bacillus sp., Providencia sp., Nitratireductor sp. and Pseudoalteromonas sp.

    CONCLUSION: In this study, bioflocculant-producing bacteria were successfully identified which are perfect candidates in forming biofloc to reduce water pollution towards a sustainable aquaculture industry. Presence of Halomonas sp. and Bacillus sp. in all stages of biofloc formation reinforces the need for new development regarding the ability of these species to be used as inoculum in forming biofloc rapidly.

  19. Karyotype of Malayan Gaur (Bos gaurus hubbacki), Sahiwal-Friesian cattle and Gaur x cattle hybrid backcrosses
    Adbullah MH, Idris I, Hilmi M
    Pak J Biol Sci, 2009 Jun 15;12(12):896-901.
    PMID: 19777782
    Interspecific hybridization has been reported for a wide variety of vertebrate species either spontaneous or by organized crossing of bovine species. The hybrids were often carrying intermediate characters genetically and phenotypically of the parents. Thus, status information of both aspects is valuable in animal production for selection and breeding management. The Gaur-cattle hybrids was reported to be superior in production value compared to their parent cattle but fertility status was still questionable. The project was abandoned due to their fertility issue and the hybrids were kept within the cattle in a dairy farm. Cytogenetic status and breeding record of the remaining herd were unavailable since then. The herd was then translocated to a deer farm (PTH Lenggong) and kept freely in the paddock. Recently, two female calves were born via inter se mating. Peripheral blood cultures of Malayan Gaur, Sahiwal-Friesian cattle and Gaur x cattle hybrid backcrosses were analyzed via Giemsa stained metaphase. The Gaur and cattle were having diploid chromosome number (2n) of 56 and 60, respectively. Interestingly, the backcrosses from the hybrids by cattle bulls were found to have two chromosome arrangements, which are 2n = 58 and 2n = 60.
  20. Large-scale culture of a tropical marine microalga Chaetoceros calcitrans (Paulsen) Takano 1968 at different temperatures using annular photobioreactors
    Lai JI, Yusoff FM, Shariff M
    Pak J Biol Sci, 2012 Jul 01;15(13):635-40.
    PMID: 24218933
    Outdoor mass culture of microalgae in the tropical area is important to minimize its production cost. This study evaluates the growth of Chaetoceros calcitrans in 120 L annular photobioreactors at indoor temperature (Treatment I, 25 +/- 2 degrees C) and outdoor tropical ambient temperature, (Treatment II, 30 +/- 6 degrees C). Each treatment was done in duplicates. For both treatments, C. calcitrans was first grown in starter columns of 10 L capacity for a period of 7 days at 25 +/- 2 degrees C. After 7 days, the 9 L culture was transferred to the annular photobioreactors and subsequently brought to a final volume of 100 L by adding 20 L fresh medium every 5 days. There was no significant difference (p > 0.05) in the dry weight of microalgae grown in natural light and those grown indoor. The results suggest that C. calcitrans can be grown in outdoor conditions, hence, saving time and microalgae production cost for the larviculture industry.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links