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  1. Fulltext Heat stress modifies the lactational performances and the urinary metabolomic profile related to gastrointestinal microbiota of dairy goats
    Contreras-Jodar A, Nayan NH, Hamzaoui S, Caja G, Salama AAK
    PLoS One, 2019;14(2):e0202457.
    PMID: 30735497 DOI: 10.1371/journal.pone.0202457
    The aim of the study is to identify the candidate biomarkers of heat stress (HS) in the urine of lactating dairy goats through the application of proton Nuclear Magnetic Resonance (1H NMR)-based metabolomic analysis. Dairy does (n = 16) in mid-lactation were submitted to thermal neutral (TN; indoors; 15 to 20°C; 40 to 45% humidity) or HS (climatic chamber; 37°C day, 30°C night; 40% humidity) conditions according to a crossover design (2 periods of 21 days). Thermophysiological traits and lactational performances were recorded and milk composition analyzed during each period. Urine samples were collected at day 15 of each period for 1H NMR spectroscopy analysis. Principal component analysis (PCA) and partial least square-discriminant analysis (PLS-DA) assessment with cross validation were used to identify the goat urinary metabolome from the Human Metabolome Data Base. HS increased rectal temperature (1.2°C), respiratory rate (3.5-fold) and water intake (74%), but decreased feed intake (35%) and body weight (5%) of the lactating does. No differences were detected in milk yield, but HS decreased the milk contents of fat (9%), protein (16%) and lactose (5%). Metabolomics allowed separating TN and HS urinary clusters by PLS-DA. Most discriminating metabolites were hippurate and other phenylalanine (Phe) derivative compounds, which increased in HS vs. TN does. The greater excretion of these gut-derived toxic compounds indicated that HS induced a harmful gastrointestinal microbiota overgrowth, which should have sequestered aromatic amino acids for their metabolism and decreased the synthesis of neurotransmitters and thyroid hormones, with a negative impact on milk yield and composition. In conclusion, HS markedly changed the thermophysiological traits and lactational performances of dairy goats, which were translated into their urinary metabolomic profile through the presence of gut-derived toxic compounds. Hippurate and other Phe-derivative compounds are suggested as urinary biomarkers to detect heat-stressed dairy animals in practice.
    Matched MeSH terms: Lactose
  2. Enhancement of viability of a probiotic Lactobacillus strain for poultry during freeze-drying and storage using the response surface methodology
    Khoramnia A, Abdullah N, Liew SL, Sieo CC, Ramasamy K, Ho YW
    Anim Sci J, 2011 Feb;82(1):127-35.
    PMID: 21269371 DOI: 10.1111/j.1740-0929.2010.00804.x
    A rotatable central composite design (CCD) was used to study the effect of cryoprotectants (skim milk, sucrose and lactose) on the survival rate of a probiotic Lactobacillus strain, L. reuteri C10, for poultry, during freeze-drying and storage. Using response surface methodology, a quadratic polynomial equation was obtained for response value by multiple regression analyses: Y = 8.59546-0.01038 X(1)-0.09382 X(2)-0.07771 X(3)-0.054861 X(1)(2)-0.04603 X(3)(2)-0.10938 X(1)X(2). Based on the model predicted, sucrose exerted the strongest effect on the survival rate. At various combinations of cryoprotectants, the viability loss of the cells after freeze-drying was reduced from 1.65 log colony forming units (CFU)/mL to 0.26-0.66 log CFU/mL. The estimated optimum combination for enhancing the survival rate of L. reuteri C10 was 19.5% skim milk, 1% sucrose and 9% lactose. Verification experiments confirmed the validity of the predicted model. The storage life of freeze-dried L. reuteri C10 was markedly improved when cryoprotectants were used. At optimum combination of the cryoprotectants, the survival rates of freeze-dried L. reuteri C10 stored at 4°C and 30°C for 6 months were 96.4% and 73.8%, respectively. Total viability loss of cells which were not protected by cryoprotectants occurred after 12 and 8 weeks of storage at 4°C and 30°C, respectively.
    Matched MeSH terms: Lactose
  3. Fulltext Beneficial Properties of Probiotics
    Shi LH, Balakrishnan K, Thiagarajah K, Mohd Ismail NI, Yin OS
    Trop Life Sci Res, 2016 Aug;27(2):73-90.
    PMID: 27688852 MyJurnal DOI: 10.21315/tlsr2016.27.2.6
    Probiotics are live microorganisms that can be found in fermented foods and cultured milk, and are widely used for the preparation of infant food. They are well-known as "health friendly bacteria", which exhibit various health beneficial properties such as prevention of bowel diseases, improving the immune system, for lactose intolerance and intestinal microbial balance, exhibiting antihypercholesterolemic and antihypertensive effects, alleviation of postmenopausal disorders, and reducing traveller's diarrhoea. Recent studies have also been focused on their uses in treating skin and oral diseases. In addition to that, modulation of the gut-brain by probiotics has been suggested as a novel therapeutic solution for anxiety and depression. Thus, this review discusses on the current probiotics-based products in Malaysia, criteria for selection of probiotics, and evidences obtained from past studies on how probiotics have been used in preventing intestinal disorders via improving the immune system, acting as an antihypercholesterolemic factor, improving oral and dermal health, and performing as anti-anxiety and anti-depressive agents.
    Matched MeSH terms: Lactose Intolerance
  4. Fulltext Isolation of lactic acid bacteria strain Staphylococcus piscifermentans from Malaysian traditional fermented shrimp cincaluk
    Hajar, S., Hamid, T.H.T.A.
    International Food Research Journal, 2013;20(1):125-129.
    MyJurnal
    Lactic acid bacteria is well known for it uses as starter culture in various fermented food, and it functions as a good natural antimicrobial agent. Cincaluk, a Malaysian fermented shrimp product commonly found in traditional dishes is commonly enriched with LAB. Out of 50 colonies from a local cincaluk, 7 strains were successfully isolated and shown to be positive in lactose utilization and catalase tests. The majority of the isolates from cincaluk showed Gram-positive cocci morphology and belonged to the group Staphyloccoccus spp. By using agar disc diffusion method, the anti-bacterial properties of these isolates (namely isolate 1, 2, 3, 4, 5, 6, and 7) moderately inhibited the growth of several pathogenic strains, i.e., Escherichia coli, Staphylococcus aureus, Salmonella typhimurium and Bacillus subtilis which were used as indicator bacteria. Other than isolates 1, 2, 3 and 5; the 16S rRNA gene for isolate 6 and 7 were successfully amplified. The 16S rRNA gene fragment from isolate 7 was successfully cloned and sequenced. Based on rRNA sequences, both isolates 6 and 7 belonged to the group Staphylococcus piscifermentans, a rare strain previously reported to be specifically isolated exclusive from fish sources.
    Matched MeSH terms: Lactose
  5. Jaundice, pale stools and hepatomegaly: but is it biliary atresia?
    Lee, W.S., Lok, F.Y.L.
    Malaysian Journal of Paediatrics and Child Health, 1998;10(2):52-54.
    MyJurnal
    A 46 day old female Chinese infant was referred for fail-ure to thrive, jaundice, hepatomegaly and bilateral cataracts. She had vomiting,blood stained stools and severe unconjugated hyperbilirubinaemia soon after birth. The jaundice persisted. At one month of age, pale stools, firm hepatomegaly and bilateral cataracts were noted. Radionuclide hepatobiliary scintigraphy per-formed at another hospital excluded biliary atresia. Investigations showed cholestasis but a negative sero-logical screening for congenital infections. A presump-tive diagnosis of galactosaemia was made and the infant was started on lactose free formula. A deficient red blood cell galactose- 1 -phosphate uridyltransferase (GALT) activity was demonstrated later. Review eight months after the initial diagnosis showed a thriving infant with no jaundice, but persisting cataracts and firm enlarged liver. A high index of clinical suspicion, labo-ratory confirmation of a deficient GALT activity and prompt withdrawal of lactose from diet are necessary to avoid any delay in diagnosis and management of this condition.
    Matched MeSH terms: Galactose; Galactosemias; Lactose
  6. The Potential Source of B. licheniformis Contamination During Whey Protein Concentrate 80 Manufacture
    Md Zain SN, Bennett R, Flint S
    J Food Sci, 2017 Mar;82(3):751-756.
    PMID: 28135405 DOI: 10.1111/1750-3841.13633
    The objective of this study was to determine the possible source of predominant Bacillus licheniformis contamination in a whey protein concentrate (WPC) 80 manufacturing plant. Traditionally, microbial contaminants of WPC were believed to grow on the membrane surfaces of the ultrafiltration plant as this represents the largest surface area in the plant. Changes from hot to cold ultrafiltration have reduced the growth potential for bacteria on the membrane surfaces. Our recent studies of WPCs have shown the predominant microflora B. licheniformis would not grow in the membrane plant because of the low temperature (10 °C) and must be growing elsewhere. Contamination of dairy products is mostly due to bacteria being released from biofilm in the processing plant rather from the farm itself. Three different reconstituted WPC media at 1%, 5%, and 20% were used for biofilm growth and our results showed that B. licheniformis formed the best biofilm at 1% (low solids). Further investigations were done using 3 different media; tryptic soy broth, 1% reconstituted WPC80, and 1% reconstituted WPC80 enriched with lactose and minerals to examine biofilm growth of B. licheniformis on stainless steel. Thirty-three B. licheniformis isolates varied in their ability to form biofilm on stainless steel with stronger biofilm in the presence of minerals. The source of biofilms of thermo-resistant bacteria such as B. licheniformis is believed to be before the ultrafiltration zone represented by the 1% WPC with lactose and minerals where the whey protein concentration is about 0.6%.
    Matched MeSH terms: Lactose
  7. Evaluating the Potential of Oleaginous Yeasts as Feedstock for Biodiesel Production
    Mukhtar H, Suliman SM, Shabbir A, Mumtaz MW, Rashid U, Rahimuddin SA
    Protein Pept Lett, 2018;25(2):195-201.
    PMID: 29359654 DOI: 10.2174/0929866525666180122112805
    BACKGROUND: Lipid-producing microorganisms, said to be oleaginous have been recognized since several years. We had investigated the effects of medium components and culturing situations on cell growth and lipid accumulation of oleaginous yeasts which were analytically examined so as to enhance lipid yield for biodiesel production.

    OBJECTIVE: The main objective of this study was to explore oleaginous yeast, Yarrowia lipolytica isolated from soil and optimization of culture conditions and medium components to obtained better quality microbial oil for biodiesel production.

    METHODS: Fifty yeast strains were isolated from soil from different regions of Lahore and eleven of them were selected for oil production. The isolated yeast colonies were screened to further check their lipid producing capabilities by the qualitative analysis. Five yeast strains were designated as oleaginous because they produced more than 16% of oil based on their biomass. To estimate the total lipid content of yeast cells, the extraction of lipids was done by performing the procedure proposed by Bligh and Dyer. The transesterification of yeast oils was performed by using different methods. There were three different strategies customized to transesterifying microbial oil using base catalyzed transesterification, acid catalyzed transesterification and enzyme-based transesterification. After completion of transesterification, sample was used for fatty acid methyl esters (FAMEs) were analyzed by gas-chromatograph with ionization detector type MS.

    RESULTS: The isolate IIB-10 identified as Yarrowia lipolytica produced maximum amount of lipids i.e. 22.8%. More amount of biomass was obtained when cane molasses was utilized as carbon source where it produced 29.4 g/L of biomass while sucrose and lactose were not utilized by IIB-10 and no biomass was obtained. Similarly, meat extracts showed best results when it was used as nitrogen source because it resulted in 35.8 g/L biomass of Yarrowia lipolytica IIB-10. The culturing conditions like size of inoculum, effect of pH and time of incubation were also studied. The 10% of inoculum size produced 25.4 g/L biomass at 120 h incubation time, while the pH 7 was the optimum pH at which 24.8 g/L biomass was produced by Yarrowia lipolytica IIB-10. GC-MS analysis showed that biodiesel produced by transesterification contained similar fatty acids as found in vegetable oil for this reason it is widely accepted feedstock for biodiesel production.

    CONCLUSION: The analysis of fatty acids methyl esters showed the similar composition of microbial oil as in vegetable oils and high amount of methyl esters were obtained after transesterification. Therefore, potentially oleaginous yeast could be used to generate a large amount of lipids for biodiesel production that will be the better substitute of petroleum-based diesel and will also control the environmental pollution.

    Matched MeSH terms: Lactose
  8. The effect of high lactose-isomaltulose on cognitive performance of young children. A double blind cross-over design study
    Taib MN, Shariff ZM, Wesnes KA, Saad HA, Sariman S
    Appetite, 2012 Feb;58(1):81-7.
    PMID: 21986189 DOI: 10.1016/j.appet.2011.09.004
    Changes in blood glucose are hypothesized to influence cognitive performance and these changes can be affected by certain nutrients. This double-blind 4-period cross-over study evaluated the effects of a slow-release modified sucrose (isomaltulose) in combination with a high concentration of lactose on cognitive performance of 5-6 year old children. Thirty children received a standard growing upmilk (Std GUM), reformulated growing up milk (Reform GUM), standard growing up milk with lactose-isomaltulose (Iso GUM), and a standard glucose drink (Glucose). The CDR System, a computerised cognitive assessment system, was used to assess various measures of attention and memory of the children at baseline (T=0), 60 (T=1), 120 (T=2), and 180 (T=3) minutes following the intake of test products. Overall, there was a decline in performance over the morning on almost every cognitive task. Children showed better attention following consumption of Iso GUM compared to Std GUM but attention was not significantly different than Reform GUM and glucose. Also, Iso GUM conferred a beneficial effect over both Reform GUM and glucose on sensitivity index of numeric working memory with no difference observed between Iso GUM and Std GUM. Surprisingly, glucose group showed lowest decline in the sensitivity index of spatial working memory and highest speed in picture recognition, although the latter was significantly better than Reform GUM only. For speed of spatial working memory, Reform GUM had the lowest decline but was significantly different only with Std GUM. There was, however, no significant difference among conditions for continuity of attention, speed of numeric working memory and picture recognition sensitivity. Despite the small sample size, the findings are intriguing as carbohydrate composition seems to influence some aspects of cognitive performance such as attention and memory. However, further studies are needed to confirm these findings.
    Matched MeSH terms: Lactose/administration & dosage*
  9. Fulltext Optimization of culture conditions for flexirubin production by Chryseobacterium artocarpi CECT 8497 using response surface methodology
    Venil CK, Zakaria ZA, Ahmad WA
    Acta Biochim. Pol., 2015;62(2):185-90.
    PMID: 25979288 DOI: 10.18388/abp.2014_870
    Flexirubins are the unique type of bacterial pigments produced by the bacteria from the genus Chryseobacterium, which are used in the treatment of chronic skin disease, eczema etc. and may serve as a chemotaxonomic marker. Chryseobacterium artocarpi CECT 8497, an yellowish-orange pigment producing strain was investigated for maximum production of pigment by optimizing medium composition employing response surface methodology (RSM). Culture conditions affecting pigment production were optimized statistically in shake flask experiments. Lactose, l-tryptophan and KH2PO4 were the most significant variables affecting pigment production. Box Behnken design (BBD) and RSM analysis were adopted to investigate the interactions between variables and determine the optimal values for maximum pigment production. Evaluation of the experimental results signified that the optimum conditions for maximum production of pigment (521.64 mg/L) in 50 L bioreactor were lactose 11.25 g/L, l-tryptophan 6 g/L and KH2PO4 650 ppm. Production under optimized conditions increased to 7.23 fold comparing to its production prior to optimization. Results of this study showed that statistical optimization of medium composition and their interaction effects enable short listing of the significant factors influencing maximum pigment production from Chryseobacterium artocarpi CECT 8497. In addition, this is the first report optimizing the process parameters for flexirubin type pigment production from Chryseobacterium artocarpi CECT 8497.
    Matched MeSH terms: Lactose/metabolism
  10. Kinetic behaviour of free lipase and mica-based immobilized lipase catalyzing the synthesis of sugar esters
    Zaidan UH, Abdul Rahman MB, Othman SS, Basri M, Abdulmalek E, Rahman RN, et al.
    Biosci Biotechnol Biochem, 2011;75(8):1446-50.
    PMID: 21821960
    The utilization of natural mica as a biocatalyst support in kinetic investigations is first described in this study. The formation of lactose caprate from lactose sugar and capric acid, using free lipase (free-CRL) and lipase immobilized on nanoporous mica (NER-CRL) as a biocatalyst, was evaluated through a kinetic study. The apparent kinetic parameters, K(m) and V(max), were determined by means of the Michaelis-Menten kinetic model. The Ping-Pong Bi-Bi mechanism with single substrate inhibition was adopted as it best explains the experimental findings. The kinetic results show lower K(m) values with NER-CRL than with free-CRL, indicating the higher affinity of NER-CRL towards both substrates at the maximum reaction velocity (V(max,app)>V(max)). The kinetic parameters deduced from this model were used to simulate reaction rate data which were in close agreement with the experimental values.
    Matched MeSH terms: Lactose/metabolism*
  11. Fulltext Optimization of Protective Agents for The Freeze-Drying of Paenibacillus polymyxa Kp10 as a Potential Biofungicide
    Nasran HS, Mohd Yusof H, Halim M, Abdul Rahman N
    Molecules, 2020 Jun 04;25(11).
    PMID: 32512825 DOI: 10.3390/molecules25112618
    Anthracnose is a fungal disease causing major losses in crop production. Chemical fungicides widely used in crop plantations to combat fungal infections can be a threat to the environment and humans in the long term. Recently, biofungicides have gained much interest as an alternative to chemical fungicides due to their environmentally friendly nature. Biofungicide products in powder form can be formulated using the freeze-drying technique to provide convenient storage. Protective agent formulation is needed in maintaining the optimal viable cells of biofungicide products. In this study, 8.10 log colony-forming unit (CFU)/mL was the highest cell viability of Paenibacillus polymyxa Kp10 at 22 h during incubation. The effects of several selected protective agents on the viability of P. polymyxa Kp10 after freeze-drying were studied. Response surface methodology (RSM) was used for optimizing formulation for the protective agents. The combination of lactose (10% w/v), skim milk (20% w/v), and sucrose (27.5% w/v) was found to be suitable for preserving P. polymyxa Kp10 during freeze-drying. Further, P. polymyxa Kp10 demonstrated the ability to inhibit fungal pathogens, Colletotrichum truncatum and C. gloeosporioides, at 60.18% and 66.52% of inhibition of radial growth, respectively.
    Matched MeSH terms: Lactose/pharmacology
  12. Fulltext Towards producing novel fish gelatin films by combination treatments of ultraviolet radiation and sugars (ribose and lactose) as cross-linking agents
    Bhat R, Karim AA
    J Food Sci Technol, 2014 Jul;51(7):1326-33.
    PMID: 24966426 DOI: 10.1007/s13197-012-0652-9
    Developing novel fish gelatin films with better mechanical properties than mammalian gelatin is a challenging but promising endeavor. Studies were undertaken to produce fish gelatin films by combining treatments with different sugars (ribose and lactose) followed 'by' 'and' ultraviolet (UV) radiation, as possible cross-linking agents. Increase in tensile strength and percent elongation at break was recorded, which was more significant in films without sugars that were exposed to UV radiation. Films with added ribose showed decreased solubility after UV treatment and exhibited higher swelling percentage than films with added lactose, which readily dissolved in water. FTIR spectra of all the films showed identical patterns, which indicated no major changes to have occurred in the functional groups as a result of interaction between gelatin, sugars and UV irradiation. The results of this study could be explored for commercial use, depending on industrial needs for either production of edible films or for food packaging purposes.
    Matched MeSH terms: Lactose
  13. Fulltext Formulation development and optimization of sustained release matrix tablet of Itopride HCl by response surface methodology and its evaluation of release kinetics
    Bose A, Wong TW, Singh N
    Saudi Pharm J, 2013 Apr;21(2):201-13.
    PMID: 23960836 DOI: 10.1016/j.jsps.2012.03.006
    The objective of this present investigation was to develop and formulate sustained release (SR) matrix tablets of Itopride HCl, by using different polymer combinations and fillers, to optimize by Central Composite Design response surface methodology for different drug release variables and to evaluate drug release pattern of the optimized product. Sustained release matrix tablets of various combinations were prepared with cellulose-based polymers: hydroxy propyl methyl cellulose (HPMC) and polyvinyl pyrolidine (pvp) and lactose as fillers. Study of pre-compression and post-compression parameters facilitated the screening of a formulation with best characteristics that underwent here optimization study by response surface methodology (Central Composite Design). The optimized tablet was further subjected to scanning electron microscopy to reveal its release pattern. The in vitro study revealed that combining of HPMC K100M (24.65 MG) with pvp(20 mg)and use of LACTOSE as filler sustained the action more than 12 h. The developed sustained release matrix tablet of improved efficacy can perform therapeutically better than a conventional tablet.
    Matched MeSH terms: Lactose
  14. First Report of Pantoea anthophila Causing Soft Rot Disease in Clausena lansium (Wampee) in China
    Zhou JN, Liu SY, Chen YF, Liao LS
    Plant Dis, 2015 Mar;99(3):416.
    PMID: 30699721 DOI: 10.1094/PDIS-10-14-1025-PDN
    Clausena lansium, also known as wampee (Clausena wampi), is a plant species native to China, Vietnam, the Philippines, Malaysia, and Indonesia, where it is widely cultivated, and also grown in India, Sri Lanka, Queensland, Florida, and Hawaii, but less frequently (3). The fruit can be consumed fresh or made into juice, jam, or succade. In summer to fall 2014, a soft rot disease was found in a wampee planting region in Yunan County, Guangdong Province, China. On Sept. 18, we collected diseased samples from a wampee orchard with about 20% disease incidence. The infected fruit initially showed pinpoint spots on the peel, water-soaked lesions, and light to dark brown discoloration. Spots expanded in 2 days, and tissues collapsed after 5 days. Severely affected fruit showed cracking or nonodorous decay. Five diseased samples were collected, and causal agents were isolated from symptomatic tissues 1 cm under the peel after surface sterilization in 0.3% NaOCl for 10 min and rinsing in sterile water three times. Tissues were placed on a Luria Bertani (LB) plate for culture. Ten representative isolates were selected for further characterization. No colony was isolated from healthy tissues. Colonies were round, smooth, with irregular edges, and produced a yellow pigment in culture. Biolog identification (Version 4.20.05) showed that all strains were gram negative, negative for indole production, and utilized glucose, maltose, trehalose, sucrose, D-lactose, and pectin but not sorbitol or gelatin. The isolates were identified as Pantoea agglomerans (SIM 0.69). Multilocus sequence analysis (MLSA) was conducted for rapid classification of the strains. Sequences of atpD, gyrB, infB, and rpoB were amplified using corresponding primers (2). All sequences of the 10 isolates were identical in each gene. BLASTn was performed, and maximum likelihood trees based on the concatenated nucleotide sequences of the four genes were constructed using MEGA6. Bootstrap values after 1,000 replicates were expressed as percentages. Results showed that the tested strain named CL1 was most homologous to P. anthophila, with 98% identity for atpD (KM521543), 100% for gyrB (KM521544), infB (KM521545), and rpoB (KM521546). The 16S rRNA sequence (KM521542) amplified by primers 27f and 1492r shared 99% identity with that of P. anthophila M19_2C (JN644500). P. anthophila was previously reclassified from P. agglomerans (3); therefore, we suggest naming this wampee pathogen P. anthophila. Subsequently, 10 wampee fruits were injected with 20 μl of bacterial suspension (1 × 108 CFU/ml) of strains CL1 and CL2, respectively, and another 10 were injected with 20 μl of LB medium as controls, all kept at 28°C for 4 days. Symptoms similar to those of natural infections were observed on inoculated fruits but not on the negative controls. Bacteria were isolated from diseased tissues and further identified as P. anthophila by gyrB sequencing. P. anthophila was reported to naturally infect balsam and marigold (1,2). To our knowledge, this is the first report of P. anthophila naturally causing soft rot disease and cracking on C. lansium (wampee). References: (1) C. Brady et al. Syst. Appl. Microbiol. 31:447, 2008. (2) C. Brady et al. Int. J. Syst. Evol. Microbiol. 59:2339, 2009. (3) J. Morton. Fruits of Warm Climates. Echo Point Books & Media, Miami, FL, 1987.
    Matched MeSH terms: Lactose
  15. First Report of Pectobacterium wasabiae Causing Soft Rot of Cabbage in Malaysia
    Golkhandan E, Sijam K, Meon S, Ahmad ZAM, Nasehi A, Nazerian E
    Plant Dis, 2013 Aug;97(8):1110.
    PMID: 30722504 DOI: 10.1094/PDIS-01-13-0112-PDN
    Soft rot of cabbage (Brassica rapa) occurs sporadically in Malaysia, causing economic damage under the hot and wet Malaysian weather conditions that are suitable for disease development. In June 2011, 27 soft rotting bacteria were isolated from cabbage plants growing in the Cameron Highlands and Johor State in Malaysia where the economic losses exceeded 50% in severely infected fields and greenhouses. Five independent strains were initially identified as Pectobacterium wasabiae based on their inability to grow at 37°C, and elicit hypersensitive reaction (HR) on Nicotiana tabaccum and their ability to utilize raffinose and lactose. These bacterial strains were gram-negative, rod-shaped, N-acetylglucosaminyl transferase, gelatin liquefaction, and OPNG-positive and positive for acid production from D-galactose, lactosemelibiose, raffinose, citrate, and trehalose. All strains were negative for indole production, phosphatase activity, reducing sucrose, and negative for acid production from maltose, sorbitol, inositol, inolin, melezitose, α-methyl-D-glucoside, and D-arabitol. All the strains exhibited pectolytic activity on potato slices. PCR assays were conducted to distinguish P. wasabiae from P. carotovorum subsp. brasiliensis, P. atrosepticum, and other Pectobacterium species using primers Br1f/L1r (2), Eca1f/Eca2r (1), and EXPCCF/EXPCCR, respectively. DNA from strains did not yield the expected amplicon with the Br1f/L1r and Eca1f/Eca2r, whereas a 550-bp amplicon typical of DNA from P. wasabiae was produced with primers EXPCCF/EXPCCR. ITS-RFLP using the restriction enzyme, Rsa I, produced similar patterns for the Malaysian strains and the P. wasabiae type strain (SCRI488), but differentiated it from P. carotovora subsp. carotovora, P. atrosepticum, P. carotovorum subsp. brasiliensis, and Dickeya chrysanthemi type strains. BLAST analysis of the 16S rRNA DNA sequence (GenBank Accession No. KC445633) showed 99% identity to the 16S rRNA of Pw WPP163. Phylogenetic reconstruction using concatenated DNA sequences of mdh and gapA from P. wasabiae Cc6 (KC484657) and other related taxa (4) clustered Malaysian P. wasabiae strains with P. wasabiae SCRI488, readily distinguishing it from other closely related species of Pectobacterium. Pathogenicity assays were conducted on leaves and stems of four mature cabbage plants for each strain (var. oleifera) by injecting 10 μl of a bacterial suspension (108 CFU/ml) into either stems or leaves, and incubating them in a moist chamber at 80 to 90% relative humidity at 30°C. Water-soaked lesions similar to those observed in the fields and greenhouses were observed 72 h after injection and bacteria with similar characteristics were consistently reisolated. Symptoms were not observed on water-inoculated controls. The pathogenicity test was repeated with similar results. P. wasabiae was previously reported to cause soft rot of horseradish in Japan (3). However, to our knowledge, this is the first report of P. wasabiae infecting cabbage in Malaysia. References: (1) S. H. De Boer and L. J. Ward. Phytopathology 85:854, 1995. (2) V. Duarte et al. J. Appl. Microbiol. 96:535, 2004. (3) M. Goto and K. Matsumoto. Int. J. Syst. Bacteriol. 37:130, 1987. (4) B. Ma et al. Phytopathology 97:1150, 2007.
    Matched MeSH terms: Galactose; Lactose
  16. Manipulation of nanofiber-based β-galactosidase nanoenvironment for enhancement of galacto-oligosaccharide production
    Misson M, Dai S, Jin B, Chen BH, Zhang H
    J Biotechnol, 2016 Mar 20;222:56-64.
    PMID: 26876609 DOI: 10.1016/j.jbiotec.2016.02.014
    The nanoenvironment of nanobiocatalysts, such as local hydrophobicity, pH and charge density, plays a significant role in optimizing the enzymatic selectivity and specificity. In this study, Kluyveromyces lactis β-galactosidase (Gal) was assembled onto polystyrene nanofibers (PSNFs) to form PSNF-Gal nanobiocatalysts. We proposed that local hydrophobicity on the nanofiber surface could expel water molecules so that the transgalactosylation would be preferable over hydrolysis during the bioconversion of lactose, thus improve the galacto-oligosaccharides (GOS) yield. PSNFs were fabricated by electro-spinning and the operational parameters were optimized to obtain the nanofibers with uniform size and ordered alignment. The resulting nanofibers were functionalized for enzyme immobilization through a chemical oxidation method. The functionalized PSNF improved the enzyme adsorption capacity up to 3100mg/g nanofiber as well as enhanced the enzyme stability with 80% of its original activity. Importantly, the functionalized PSNF-Gal significantly improved the GOS yield and the production rate was up to 110g/l/h in comparison with 37g/l/h by free β-galactosidase. Our research findings demonstrate that the localized nanoenvironment of the PSNF-Gal nanobiocatalysts favour transgalactosylation over hydrolysis in lactose bioconversion.
    Matched MeSH terms: Lactose
  17. Fulltext Critical physicochemical attributes of chitosan nanoparticles admixed lactose-PEG 3000 microparticles in pulmonary inhalation
    Alhajj N, Zakaria Z, Naharudin I, Ahsan F, Li W, Wong TW
    Asian J Pharm Sci, 2020 May;15(3):374-384.
    PMID: 32636955 DOI: 10.1016/j.ajps.2019.02.001
    Chitosan nanoparticles are exhalation prone and agglomerative to pulmonary inhalation. Blending nanoparticles with lactose microparticles (∼5 µm) could mutually reduce their agglomeration through surface adsorption phenomenon. The chitosan nanoparticles of varying size, size distribution, zeta potential, crystallinity, shape and surface roughness were prepared by spray drying technique as a function of chitosan, surfactant and processing conditions. Lactose-polyethylene glycol 3000 (PEG3000) microparticles were similarly prepared. The chitosan nanoparticles, physically blended with fine lactose-PEG3000 microparticles, exhibited a comparable inhalation performance with the commercial dry powder inhaler products (fine particle fraction between 20% and 30%). Cascade impactor analysis indicated that the aerosolization and inhalation performance of chitosan nanoparticles was promoted by their higher zeta potential and circularity, and larger size attributes of which led to reduced inter-nanoparticulate aggregation and favored nanoparticles interacting with lactose-PEG3000 micropaticles that aided their delivery into deep and peripheral lungs.
    Matched MeSH terms: Lactose
  18. Fulltext Lactococcus Lactis Strain A5 Producing Nisin-like Bacteriocin Active against Gram Positive and Negative Bacteria
    Azhar NS, Md Zin NH, Hamid THTA
    Trop Life Sci Res, 2017 Jul;28(2):107-118.
    PMID: 28890764 MyJurnal DOI: 10.21315/tlsr2017.28.2.8
    In this study, a Lactic acid bacteria (LAB) strain was isolated on MRS medium from gastro-intestinal tissues of Broadhead catfish (Clarias macrocephalus). Out of 50 isolates, 25 isolates were found to be positive on lactose utilisation test and were identified to be gram positive cocci. Using disc diffusion methods, one out of 22 isolates, i.e., a strain A5 demonstrated inhibitions against three indicator organisms; Bacillus cereus, Staphylococcus aureus and Salmonella thyphimurium. Partial 16S rDNA sequencing identified isolate A5 as a member of Lactococcus lactis, with 100% DNA homology. Cell free supernatant fluid from Lactococcus lactis A5 showed inhibitory activities against both gram positive pathogens (Bacillus cereus and Staphylococcus aureus) and gram negative pathogens (Salmonella thyphimurium). Chloroform precipitated bacteriocin retained antagonistic activities in the presence of catalase and lysozyme; and was completely inactivated by Proteinase K treatment. The bacteriocin has a molecular weight of 3.4 kDa, based on SDS-PAGE analysis and the extract was heat stable at 37°C and 65°C, for 15 minutes. The antibacterial activity was suppressed with the addition of EDTA but was significantly increased with the addition of SDS, Triton X-100, Tween 20 and Tween 80. This bacteriocin belongs to class 1 bacteriocin, which was shown to have a nisin-like properties. This strain can be used as potential probiotics in animal or aquaculture feeding; and the bacteriocin it produces will be useful in food preservative.
    Matched MeSH terms: Lactose
  19. Fulltext Amount and types of sugars in selected commercial and traditional kuih in Klang Valley, Malaysia
    Sharifah Azizah, T.N., Nik Shanita, S., Hasnah, H.
    International Food Research Journal, 2015;22(6):2642-2649.
    MyJurnal
    The aim of this study was to determine the specific content and type of sugars in selected commercial and traditional kuih in Klang Valley. The selection of the kuih was based on the validated Food Frequency Questionnaire (FFQ) for sugar. The selected commercial kuih was doughnut coated with sugar (Big Apple) while the ten traditional kuih samples consisted of kuih bingka ubi, kuih kasui, kuih keria, kuih koci, kuih lapis, kuih lopes, kuih onde-onde, kuih sagu, kuih seri muka and kuih talam. The doughnut coated with sugar (Big Apple) was purchased from Big Apple Donuts and Coffee franchise at two different locations, while the traditional kuih were randomly bought from stalls, cafeterias and restaurants around Kuala Lumpur and Rawang. The types and amount of sugar were determined using High Performance High Chromatography (HPLC) with a refractive index (RI) detector. Results showed that doughnut coated with sugar (Big Apple) has the highest starch content (22.6±0.3 g/100g) and kuih keria contained the highest available carbohydrate (41.5±1.7 g/100g), comprising of 24.2±2.4 g/100g total sugar and 17.3±0.7 g/100g of starch. The least available carbohydrate content was found in kuih talam (20.0±0.5 g/100g), which was 50% lower than the one in kuih keria. Major individual sugars detected in all kuih samples were consisted of sucrose (60.0%), glucose (16.2%), fructose (14.0%), maltose (9.5%) and lactose (0.3%). Majority of the kuih samples (90.9%) in this study can be categorized as medium sugar while only kuih keria was categorized as high sugar. Based on the two main ingredients (sugar and flour) used in the preparation of kuih, results showed that all kuih samples can be categorized as medium sugarmedium starch. In conclusion, this study served as a guideline by locals in selecting kuih of
    different sugar levels.
    Matched MeSH terms: Lactose
  20. Fulltext Kinetic modeling of bacteriocin-like inhibitory substance secretion by Pediococcus acidilactici Kp10 and its stability in food manufacturing conditions
    Abbasiliasi S, Tan JS, Ibrahim TAT, Ramanan RN, Kadkhodaei S, Mustafa S, et al.
    J Food Sci Technol, 2018 Apr;55(4):1270-1284.
    PMID: 29606741 DOI: 10.1007/s13197-018-3037-x
    This paper deliberates the modelling and validation of bacteriocin-like inhibitory substance (BLIS) secretion by Pediococcus acidilactici Kp10 at different agitation speeds in a stirred tank bioreactor. A range of models namely the re-parameterised logistic, Luedeking-Piret and maintenance energy were assessed to predict the culture performance of the said bacterium. Growth of P. acidilactici Kp10 was enhanced with increased agitation speed up to 600 rpm while BLIS secretion was maximum at 400 rpm but decreased at higher agitation speed. Growth of P. acidilactici aptly subscribed to the re-parameterised logistic model while BLIS secretion and lactose consumption fitted well with the Luedeking-Piret model. The models revealed a relationship between growth of the bacterium and BLIS secretion. Bacterial growth and BLIS secretion were largely affected by the agitation speed of the stirred tank bioreactor which regulated the oxygen transfer to the culture. BLIS secretion by P. acidilactici Kp10 was however enhanced in oxygen-limited culture. The study also assessed BLIS from the perspective of its stability when subjected to factors such as temperature, pH and detergents. Results showed that BLIS produced by this strain was not affected by heat (at 25-100 °C for 20 min and at 121 °C for 15 min), surfactant (Tween 40, 60 and 80 and urea), detergents (up to 1% SDS), organic solvents (50% each of acetone, methanol and ethanol) and stable in a wide range of pH (2-10). The above information are pertinent with reference to commercial applications of this bacterial product in food manufacturing which invariably involve various sterilization processes and subjected to a wide pH range.
    Matched MeSH terms: Lactose
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