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Draft Genome Sequence of a Biosurfactant-Producing Bacillus subtilis UMX-103 Isolated from Hydrocarbon-Contaminated Soil in Terengganu, Malaysia

Abdelhafiz YA, Manaharan T, BinMohamad S, Merican AF

Curr Microbiol, 2017 Apr 17.
PMID: 28417189 DOI: 10.1007/s00284-017-1249-3

The draft genome here presents the sequence of Bacillus subtilis UMX-103. The bacterial strain was isolated from hydrocarbon-contaminated soil from Terengganu, Malaysia. The whole genome of the bacterium was sequenced using Illumina HiSeq 2000 sequencing platform. The genome was assembled using de novo approach. The genome size of UMX-103 is 4,234,627 bp with 4399 genes comprising 4301 protein-coding genes and 98 RNA genes. The analysis of assembled genes revealed the presence of 25 genes involved in biosurfactant production, where 14 of the genes are related to biosynthesis and 11 of the genes are in the regulation of biosurfactant productions. This draft genome will provide insights into the genetic bases of its biosurfactant-producing capabilities.

Matched MeSH terms: Bacillus subtilis
Fulltext Draft Genome Sequence of the Prazosin-Degrading Bacillus sp. Strain PR5, Isolated from a River Receiving Hospital and Urban Wastewater in Malaysia

Ahmad Sabri NS, Mohd Mohsi NF, Apandi A, Yusof N, Megat Mohd Noor MJ, Md Akhir FN, et al.

Microbiol Resour Announc, 2021 Mar 18;10(11).
PMID: 33737348 DOI: 10.1128/MRA.00025-21

We report the complete genome sequence of Bacillus sp. strain PR5, isolated from a river receiving hospital and urban wastewater in Malaysia, which demonstrated a high capability for degrading prazosin. This genome sequence of 4,525,264 bp exhibited 41.5% GC content, 4,402 coding sequences, and 32 RNAs.

Matched MeSH terms: Bacillus
Fulltext Effect of Javanese turmeric (Curcuma xanthorrhiza Roxb.) extract on natural microflora of oyster mushroom (Pleurotus sajur-caju) and its sensory acceptability

Lew, K.F., Goh, G.L, Son, R., Rukayadi, Y.

International Food Research Journal, 2015;22(6):2446-2451.
MyJurnal

The effects of methanolic extract of Javanese turmeric (Curcuma xanthorrhiza Roxb.) at different level of concentrations on the inactivation of Bacillus cereus, Escherichia coli, Pseudomonas spp. and Staphylococcus aureus in oyster mushroom (Pleurotus sajor-caju) were investigated. This study was conducted principally for the achievement on the best combination between the
susceptibility of C. xanthorrhiza extract on natural microflora and foodborne pathogenic bacteria with the sensory acceptability of the soaked oyster mushroom. Three different concentrations (g/ml), 0.05%, 0.50% and 5.00%, of C. xanthorrhiza extract prepared with dilution method were designed as sanitizing agent in treating the oyster mushroom at 5 minutes and 10 minutes.
There was significance reduction in the survival of microbial load between the untreated fresh oyster mushroom and those soaked with 0.05%, 0.50% and 5.00% rhizome extract (P

Matched MeSH terms: Bacillus cereus
Fulltext Effect of dried and extrudate of bitter gourd fruit on epithelial microflora in raw chicken legs meat

Rukayadi, Y., Abdulkarim, S.M., Sulaiman, R., Abdelkarim, H.

International Food Research Journal, 2017;24(5):2253-2258.
MyJurnal

Plants have been used recently to eliminate bacterial growth in food products. This study was undertaken to test the in vitro sanitizing effect of crude extract from bitter gourd (BG) fruit on the growth of native microorganisms in raw chicken leg meat. Hot air dried BG and extrudate extracts at 1% concentration and exposure times of (5, 10 and 15 min) were used to treat the samples using dilution method. Results showed that BG extrudate had a slightly stronger bactericidal activity against the microflora than the B.G. hot air drying treatment, especially, on E. coli at all exposure time. Overall, there is no significant difference between the treatments; Total Plate Count (TPC), Escherichia coli, Bacillus cereus, Staphylococcus aureus. The best reduction time of microflora by hot air dried extract was at (15 min) except for B. cereus was at (5 min) and for extrudate extract was at (5 min) except for E. coli was at (10 min). In conclusion, bitter gourd extract could be used as an important natural sanitizer for rinsing raw food matrials such chicken meat.

Matched MeSH terms: Bacillus cereus
Fulltext Effect of extraction solvents on antioxidant and antimicrobial properties of fenugreek seeds (Trigonella foenum-graecum L.)

Norziah, M.H., Bhat, R., Ahmad, M.

International Food Research Journal, 2015;22(3):1261-1271.
MyJurnal

The present study was aimed to investigate the efficacy of fenugreek seeds as a potential natural source of antioxidants and antimicrobials. Fenugreek seed (FS) extracts were prepared using ethanol (75%), methanol (75%) and water as extraction solvents. Ethanol (E-FSP), methanol (M-FSP), water (W-FSP) and hot water (HW-FSP) extracts were obtained from ground FS, whilst water extract (W-GeFS) was obtained from germinated FS. The results revealed that all extracts of the ground FS exhibited antioxidant and antimicrobial activities and the extractability of bioactive compounds in the presence of water was higher in germinated seeds (W-GeFS). Highest phenolic (156.3 mg GAE/ g) and flavonoid (38.5 mg CE/ g) contents were found in W-GeFS. It also showed the strongest DPPH radical-scavenging activity of 68 % inhibition at a lower concentration (0.06 mg/ ml). In addition, highest vitamin C equivalent antioxidant capacity (143.28 mg vitamin C/ g) with an IC50 value of 42.1 μg/ ml were found in W-GeFS. Based on disc diffusion method, W-GeFS exhibited highest antimicrobial activity against all tested bacterial pathogens (Bacillus subtilis, Staphylococcus aureus, and Escherichia coli). Thus, it can be concluded from the results that W-GeFS extract from germinating fenugreek seeds (W-GeFS) has the potential to be used as a natural source of bioactive compounds with varied applications in food industry especially, for active film packaging purposes to prolong the shelf-life of food products.

Matched MeSH terms: Bacillus subtilis
Fulltext Effect of fennel (Foeniculum vulgare Mill.) and coriander (Coriandrum sativum L.) on microbial quality and sensory acceptability of frozen paratha

Rosli, N.A., Azilan, N A., Mahyudin, N.A., Mahmud Ab Rashid, N.K., Meon, F.N.S., Ismail, Z., et al.

International Food Research Journal, 2019;26(3):945-952.
MyJurnal

Fennel (Foeniculum vulgare Mill.) and coriander (Coriandrum sativum L.) are known to possess good antimicrobial properties. In the present work, spice-infused frozen parathas were formulated to investigate the effect of fennel and coriander on microbial (aerobic mesophilic bacteria, yeast and mould, and Bacillus cereus) reduction and sensory acceptability of frozen paratha throughout the storage at -18°C. The present work was also aimed at determining the relationship between spice concentrations and storage durations on microbiological quality of the samples. Fennel and coriander seed powder were used at concentrations of 2, 4 and 6% of wheat flour (w/w). The microbiological analysis was performed by total plate count, yeast and mould count, and Bacillus cereus count after 9, 12 and 15 weeks of storage. Sensory evaluation was conducted using hedonic scales at the end of storage durations. Results showed that spice infusion in frozen paratha significantly delayed the growth of aerobic mesophilic bacteria, yeasts and moulds, and Bacillus cereus during storage. The lowest log count was demonstrated by coriander at 6% in total plate count (3.85, 3.90 and 3.91 log10 CFU/g), and yeast and mould count (2.54, 2.59 and 2.60 log10 CFU/g) after 9, 12 and 15 weeks, respectively. Bacillus cereus was not detected throughout the storage durations. Fennel exhibited minimum activity against Bacillus cereus with no significant difference on log count reduction when compared with control. Coriander showed the highest decrease in both total plate count and Bacillus cereus count during the storage duration. Sensory evaluation result indicated that control sample exhibited the highest preference over all attributes when compared with fennel and coriander. Coriander-infused paratha was slightly darker in colour due to high concentration of 6%. Fennel yielded the lowest score in terms of taste among all samples. Fennel and coriander showed no significant difference for sensory acceptability. Overall, all frozen parathas were in good quality after 15 weeks of frozen storage. It can thus be concluded that fennel and coriander can be used as potential natural preservatives to inhibit the growth of microorganisms in paratha during frozen storage. Nevertheless, the optimum spice concentration should be determined to minimise the effects on the sensory attributes.

Matched MeSH terms: Bacillus cereus
Effect of signal peptides on the secretion of β-cyclodextrin glucanotransferase in Lactococcus lactis NZ9000

Subramaniam M, Baradaran A, Rosli MI, Rosfarizan M, Khatijah Y, Raha AR

J. Mol. Microbiol. Biotechnol., 2012;22(6):361-72.
PMID: 23295307 DOI: 10.1159/000343921

Cyclodextrin glucanotransferase (CGTase) is an extracellular enzyme which catalyzes the formation of cyclodextrin from starch. The production of CGTase using lactic acid bacterium is an attractive alternative and safer strategy to produce CGTase. In this study, we report the construction of genetically modified Lactococcus lactis strains harboring plasmids that secrete the Bacillus sp. G1 β-CGTase, with the aid of the signal peptides (SPs) SPK1, USP45 and native SP (NSP). Three constructed vectors, pNZ:NSP:CGT, pNZ:USP:CGT and pNZ:SPK1:CGT, were developed in this study. Each vector harbored a different SP fused to the CGTase. The formation of halo zones on starch plates indicated the production and secretion of β-CGTase by the recombinants. The expression of this enzyme is shown by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and zymogram analysis. A band size of ∼75 kDa corresponding to β-CGTase is identified in the intracellular and the extracellular environments of the host after medium modification. The replacement of glucose by starch in the medium was shown to induce β-CGTase production in L. lactis. Although β-CGTase production is comparatively low in NZ:SPK1:CGT, the SP SPK1 was shown to have higher secretion efficiency compared to the other SPs used in this study.

Matched MeSH terms: Bacillus/enzymology; Bacillus/genetics
Fulltext Effects of Bacillus subtilis on the growth performance, digestive enzymes, immune gene expression and disease resistance of white shrimp, Litopenaeus vannamei

Zokaeifar H, Balcázar JL, Saad CR, Kamarudin MS, Sijam K, Arshad A, et al.

Fish Shellfish Immunol, 2012 Oct;33(4):683-9.
PMID: 22659618 DOI: 10.1016/j.fsi.2012.05.027

We studied the effect of two probiotic Bacillus subtilis strains on the growth performance, digestive enzyme activity, immune gene expression and disease resistance of juvenile white shrimp (Litopenaeus vannamei). A mixture of two probiotic strains, L10 and G1 in equal proportions, was administered at two different doses 10(5) (BM5) and 10(8) (BM8) CFU g(-1) feed to shrimp for eight weeks. In comparison to untreated control group, final weight, weight gain and digestive enzyme activity were significantly greater in shrimp fed BM5 and BM8 diets. Significant differences for specific growth rate (SGR) and survival were recorded in shrimp fed BM8 diet as compared with the control; however, no significant differences were recorded for food conversion ratio (FCR) among all the experimental groups. Eight weeks after the start of the feeding period, shrimp were challenged with Vibrio harveyi. Statistical analysis revealed significant differences in shrimp survival between probiotic and control groups. Cumulative mortality of the control group was 63.3%, whereas cumulative mortality of the shrimp that had been given probiotics was 20.0% with BM8 and 33.3% with BM5. Subsequently, real-time PCR was employed to determine the mRNA levels of prophenoloxidase (proPO), peroxinectin (PE), lipopolysaccharide- and β-1,3-glucan-binding protein (LGBP) and serine protein (SP). The expression of all immune-related genes studied was significantly up-regulated (P

Matched MeSH terms: Bacillus subtilis/genetics; Bacillus subtilis/immunology*
Effects of Methanol Extract of Wedelia chinensis Osbeck (Asteraceae) Leaves against Pathogenic Bacteria with Emphasise on Bacillus cereus

Darah I, Lim SH, Nithianantham K

Indian J Pharm Sci, 2013 Sep;75(5):533-9.
PMID: 24403653

The antibacterial activity of the methanol extract of Wedelia chinensis leave was studied and tested against three pathogenic Gram positive bacteria (Bacillus cereus, B. subtilis and Stapylococcus aureus) and three pathogenic Gram negative bacteria (Escherichia coli, Proteus rettgeri and Pseudomonas aeruginosa) by the disk diffusion assay and broth dilution methods. The extract exhibited favourable antibacterial activity against the bacterial cells but was more potent against Gram positive bacteria with the minimum inhibition concentration of 3.12 to 6.25 mg/ml compared to the Gram negative bacteria which had minimum inhibition concentration values of 25 mg/ml. The time-kill study suggested that the extract possessed bactericidal properties at higher concentrations and eradicated the growth of bacterial cells. The major abnormalities occurred to the bacterial cells after exposed to the extract were complete alterations in their morphology and collapsed of the cells beyond repair. The methanol extract of W. chinensis may be an effective antibacterial agent to treat bacterial infections.

Matched MeSH terms: Bacillus cereus
Fulltext Effects of proton pump inhibitor on the human gut microbiome profile in multi-ethnic groups in Singapore

Koo SH, Deng J, Ang DSW, Hsiang JC, Lee LS, Aazmi S, et al.

Singapore Med J, 2019 Oct;60(10):512-521.
PMID: 30488079 DOI: 10.11622/smedj.2018152

INTRODUCTION: The objectives of this study were to examine the effects of ethnicity, gender and a proton pump inhibitor (PPI), omeprazole, on the human gut microbiome. PPIs are commonly used for the treatment of acid-related disorders. We hypothesised that PPI therapy might perturb microbial communities and alter the gut microbiome.
METHODS: Healthy subjects of Chinese (n = 12), Malay (n = 12) and Indian (n = 10) ancestry, aged 21-37 years, were enrolled. They provided a baseline stool sample (Day 1) and were then given a course of omeprazole at therapeutic dose (20 mg daily) for seven days. Stool samples were collected again on Day 7 and 14 (one week after stopping omeprazole). Microbial DNA was extracted from the stool samples, followed by polymerase chain reaction, library construction, 16S rRNA sequencing using Illumina MiSeq, and statistical and bioinformatics analyses.
RESULTS: The findings showed an increase in species richness (p = 0.018) after omeprazole consumption on Day 7, which reverted to baseline on Day 14. There were significant increases in the relative abundance of Streptococcus vestibularis (p = 0.0001) and Veillonella dispar (p = 0.0001) on Day 7, which diminished on Day 14. Faecalibacterium prausnitzii, Sutterella stercoricanis and Bacteroides denticanum were characteristic of Chinese, Malays and Indians, respectively. Lactobacillaceae and Bacteroides xylanisolvens were the signature taxa of male and female subjects, respectively.
CONCLUSION: The study demonstrated alterations in the gut microbiome following omeprazole treatment. This may explain the underlying pathology of increased risk of Clostridium difficile infections associated with omeprazole therapy.

Matched MeSH terms: Bacillus/isolation & purification
Fulltext Efficacy of Insecticide and Bioinsecticide Ground Sprays to Control Metisa plana Walker (Lepidoptera: Psychidae) in Oil Palm Plantations, Malaysia

Salim H, Rawi CS, Ahmad AH, Al-Shami SA

Trop Life Sci Res, 2015 Dec;26(2):73-83.
PMID: 26868711 MyJurnal

The effectiveness of the synthetic insecticides trichlorfon, lambda-cyhalothrin, cypermethrin emulsion concentrated (EC) and cypermethrin emulsion water based (EW) and a bio-insecticide, Bacillus thuringiensis subsp. kurstaki (Btk), was evaluated at 3, 7, 14 and 30 days after treatment (DAT) for the control of Metisa plana larvae in an oil palm (Elaeis guineensis) plantation in Malaysia. Although all synthetic insecticides effectively reduced the larval population of M. plana, trichlorfon, lambda-cyhalothrin and cypermethrin EC were the fastest-acting. The larval population dropped below the economic threshold level (ETL) 30 days after a single application of the synthetic insecticides. Application of Btk, however, gave poor results, with the larval population remaining above the ETL post treatment. In terms of operational productivity, ground spraying using power spray equipment was time-consuming and resulted in poor coverage. Power spraying may not be appropriate for controlling M. plana infestations in large fields. Using a power sprayer, one man could cover 2-3 ha per day. Hence, power spraying is recommended during outbreaks of infestation in areas smaller than 50 ha.

Matched MeSH terms: Bacillus thuringiensis
Efficacy of a Bacillus thuringiensis israelensis tablet formulation, vectobac DT, for control of dengue mosquito vectors in potable water containers

Benjamin S, Rath A, Fook CY, Lim LH

Southeast Asian J. Trop. Med. Public Health, 2005 Jul;36(4):879-92.
PMID: 16295540

VectoBac DT, a tablet formulation of Bacillus thuringiensis israelensis (Bti) was evaluated for the potential control of dengue vectors in various types of potable water containers. On introduction to containers, the tablet sinks to the bottom and the Bti toxins are found concentrated at the sides and the base, while the treated water column is free of Bti toxins within 24 hours after tablet introduction. In a simulated study, earthen, HDPE and plastic containers were kept covered and laboratory-bred larvae were introduced to determine the control by the tablet. The efficacy and persistence of the tablet, with a control of > 90%, was significantly longer in earthen containers in comparison to the HDPE and plastic containers. Efficacy and persistence were observed in earthen containers for a minimum period of 5.5 months (166 days) both without water replenishment and with weekly, 50% water volume, replenishment, and for a maximum period of 2.2 months (66 days) with daily, 50% water volume, replenishment. In plastic and HDPE containers, the tablet activity had a persistence of 2.1 months (63 days) without water replenishment and 1.8 months (54 days) with weekly water replenishment. The efficacy and persistence of the VectoBac DT was significantly longer in the earthen containers, with or without regularly treated water exchange, due to the Bti toxins being embedded in the porous earthen container surfaces, which protects them from rapid degradation. Lesser toxin amounts are removed from the water column during water exchange. The efficacy of VectoBac DT was also evaluated for the control of natural infestation of Aedes larvae which were resistant to temephos at the WHO diagnostic dosage of 0.012 mg/l. The tablet significantly reduced the pupal density by 8 fold in earthen containers for 67 days and 5 fold in HDPE containers for 55 days in comparison to untreated containers (p < 0.05). However, the tablet was effective for a shorter period of 25 days post-tablet-introduction due to fungal infestation in the treated plastic containers. There is a need to determine the capacity of the VectoBac DT to reduce the dengue vector population to a threshold which will prevent dengue outbreaks in dengue endemic areas.

Matched MeSH terms: Bacillus thuringiensis*
Encapsulation of Bacillus salmalaya 139SI using double coating biopolymer technique

Vejan P, Abdullah R, Khadiran T, Ismail S

Lett Appl Microbiol, 2019 Jan;68(1):56-63.
PMID: 30339728 DOI: 10.1111/lam.13088

Sustainable crop production for a rapidly growing human population is one of the current challenges faced by the agricultural sector. However, many of the chemical agents used in agriculture can be hazardous to humans, non-targeted organism and environment. Plant growth promoting rhizobacteria have demonstrated a role in promoting plant growth and health under various stress conditions including disease. Unfortunately, bacterial viability degrades due to temperature and other environmental factors (Bashan et al., Plant Soil 378: 1-33, 2014). Encapsulation of bacteria into core-shell biopolymers is one of the promising techniques to overcome the problem. This study deals with the encapsulation of Bacillus salmalaya 139SI using simple double coating biopolymer technique which consist of brown rice protein/alginate and 0·5% low molecular weight chitosan of pH 4 and 6. The influence of biopolymer to bacteria mass ratio and the chitosan pH on the encapsulation process, physic-chemical, morphology and bioactivity properties of encapsulated B. salmalaya 139SI have been studied systematically. Based on the analysis of physico-chemical, morphology and bioactivity properties, B. salmalaya 139S1 encapsulated using double coating encapsulation technology has promising viability pre- and postfreeze-drying with excellent encapsulation yields of 99·7 and 89·3% respectively. SIGNIFICANCE AND IMPACT OF THE STUDY: The need of a simple yet effective way of encapsulating plant growth promoting rhizobacteria is crucial to further improve their benefits to global sustainable agriculture practice. Effective encapsulation allows for protection, controlled release and function of the micro-organism, as well as providing a longer shelf life for the product. This research report offers an innovative yet simple way of encapsulating using double coating technology with environmentally friendly biopolymers that could degrade and provide nutrients when in soil. Importantly, the bioactivity of the bacteria is maintained upon encapsulation.

Matched MeSH terms: Bacillus/metabolism*
Fulltext Endophytic Bacteria Isolated from Citrus Plants for Biological Control of Citrus Canker in Lime Plants

Daungfu O, Youpensuk S, Lumyong S

Trop Life Sci Res, 2019 Jan;30(1):73-88.
PMID: 30847034 DOI: 10.21315/tlsr2019.30.1.5

Citrus canker caused by Xanthomonas citri subsp. citri is a disease affecting the yield and fruit quality of lime (Citrus aurantiifolia). This research investigated endophytic bacteria obtained from six healthy Citrus spp. to inhibit the pathogen and to control citrus canker on lime plants. Numbers of the endophytic bacteria isolated from C. aurantifolia, C. hystrix, C. maxima, C. nobilis, C. reticulata and C. sinensis were 28, 25, 29, 42, 12 and 34 isolates, respectively. The selected endophytic bacteria that were effective against X. citri subsp. citri were Bacillus amyloliquefaciens LE109, B. subtilis LE24 and B. tequilensis PO80. The optimum culture medium for an antagonistic effect on the pathogen in B. amyloliquefaciens LE109 and B. tequilensis PO80 was yeast extract peptone dextrose broth, and in B. subtilis LE24 was modified soluble starch broth. To control citrus canker in lime, young expanded leaves of lime plants were aseptically punctured and inoculated with 30 μl of bacterial suspension of the pathogen (108 CFU/ml in 0.85% NaCl) per punctured location. After the pathogenic inoculation for 24 h, the leaves were then inoculated with 30 μl of the selected endophytic bacteria (108 CFU/ml in 0.85% NaCl), and treated with 30 μl of the culture media containing bioactive compounds produced by the selected endophytic bacteria. The leaves inoculated with cell suspensions of B. amyloliquefaciens LE109 or B. subtilis LE24 could completely control citrus canker. However, the leaves inoculated with B. tequilensis PO80 displayed 10% disease incidence. Additionally, the leaves treated with the crude bioactive compounds of B. amyloliquefaciens LE109 or B. subtilis LE24 could completely control citrus canker. Notably, the leaves treated with the crude bioactive compounds of B. tequilensis PO80 displayed 5% disease incidence. The results of this study showed that the Bacillus strains play important roles in the biocontrol of citrus canker in lime.

Matched MeSH terms: Bacillus; Bacillus subtilis; Bacillus amyloliquefaciens
Enhancement of thermostable lipase production by a genotypically identified extremophilic Bacillus subtilis NS 8 in a continuous bioreactor

Olusesan AT, Azura LK, Abubakar F, Mohamed AK, Radu S, Manap MY, et al.

J. Mol. Microbiol. Biotechnol., 2011 Apr;20(2):105-15.
PMID: 21422764 DOI: 10.1159/000324535

Bacillus strain NS 8, a lipase-producing bacterium isolated from a Malaysian hot spring, is able to tolerate a broad range of temperature and pH, which makes it beneficial for this study. It generated PCR products with molecular weight of 1,532 bp, and the 16S rRNA sequence analysis identified it as Bacillus subtilis with accession number AB110598. It showed a 71% similarity index with B. subtilis using Biolog Microstation System. Its lipase production was optimized using a shake flask system by changing the physical (agitation speed, pH and temperature) and nutritional (nitrogen, carbon and minerals) factors. The most suitable combination of the basal medium for lipase production was 2.5% olive oil (carbon), 1.5% peptone (nitrogen), 0.1% MgSO(4) (mineral) at an optimum temperature of 50°C, pH 7.5 and 150 rpm agitation, giving an enzyme yield of 4.23 U/ml. Statistical optimization using response surface methodology was carried out. An optimum lipase production of 5.67 U/ml was achieved when olive oil concentration of 3%, peptone 2%, MgSO(4)·7H(2)O 0.2% and an agitation rate of 200 rpm were combined. Lipase production was further carried out inside a 2-liter bioreactor, which yielded an enzyme activity of 14.5 U/ml after 15 h of incubation.

Matched MeSH terms: Bacillus subtilis/classification; Bacillus subtilis/enzymology*; Bacillus subtilis/growth & development*; Bacillus subtilis/isolation & purification
Fulltext Enhancement of β-Mannanase Production by Bacillus subtilis ATCC11774 through Optimization of Medium Composition

Norizan NABM, Halim M, Tan JS, Abbasiliasi S, Mat Sahri M, Othman F, et al.

Molecules, 2020 Jul 31;25(15).
PMID: 32752106 DOI: 10.3390/molecules25153516

Palm kernel cake (PKC) has been largely produced in Malaysia as one of the cheap and abundant agro-waste by-products from the palm oil industry and it contains high fiber (mannan) content. The present study aimed to produce β-mannanase by Bacillus subtilis ATCC11774 via optimization of the medium composition using palm kernel cake as substrate in semi-solid fermentation. The fermentation nutrients such as PKC, peptone, yeast extract, sodium chloride, magnesium sulphate (MgSO2), initial culture pH and temperature were screened using a Plackett-Burman design. The three most significant factors identified, PKC, peptone and NaCl, were further optimized using central composite design (CCD), a response surface methodology (RSM) approach, where yeast extract and MgSO2 were fixed as a constant factor. The maximum β-mannanase activity predicted by CCD under the optimum medium composition of 16.50 g/L PKC, 19.59 g/L peptone, 3.00 g/L yeast extract, 2.72 g/L NaCl and 0.2 g/L MgSO2 was 799 U/mL. The validated β-mannanase activity was 805.12 U/mL, which was close to the predicted β-mannanas activity. As a comparison, commercial media such as nutrient broth, M9 and Luria bertani were used for the production of β-mannanase with activities achieved at 204.16 ± 9.21 U/mL, 50.32 U/mL and 88.90 U/mL, respectively. The optimized PKC fermentation medium was four times higher than nutrient broth. Hence, it could be a potential fermentation substrate for the production of β-mannanase activity by Bacillus subtilis ATCC11774.

Matched MeSH terms: Bacillus subtilis/growth & development; Bacillus subtilis/metabolism*
Fulltext Enhancing food waste biodegradation rate in a food waste biodigester with the synergistic action of hydrolase-producing Bacillus paralicheniformis GRA2 and Bacillus velezensis TAP5 co-culture inoculation

Roslan MAM, Jefri NQUA, Ramlee N, Rahman NAA, Chong NHH, Bunawan H, et al.

Saudi J Biol Sci, 2021 May;28(5):3001-3012.
PMID: 34012331 DOI: 10.1016/j.sjbs.2021.02.041

Food waste (FW) minimization at the source by using food waste biodigester (FWBs) has a vast potential to lower down the impact of increasing organic fraction in municipal solid waste generation. To this end, this research sought to check the performance of locally isolated hydrolase-producing bacteria (HPB) to improve food waste biodegradation rate. Two under-explored HPB identified as Bacillus paralicheniformis GRA2 and Bacillus velezensis TAP5 were able to produce maximum amylase, cellulase, protease and lipase activities, and demonstrated a significant hydrolase synergy in co-culture fermentation. In vitro biodegradation analysis of both autoclaved and non-autoclaved FW revealed that the HPB inoculation was effective to degrade total solids (>62%), protein (>19%), total fat (>51), total sugar (>86%), reducing sugar (>38%) and starch (>50%) after 8-day incubation. All co-culture treatments were recorded superior to the respective monocultures and the uninoculated control. The results of FW biodegradation using batch-biodigester trial indicated that the 1500 mL and 1000 mL inoculum size of HPB inoculant reached a plateau on the 4th day, with gross biodegradation percentage (GBP) of >85% as compared to control (66.4%). The 1000 mL inoculum was sufficient to achieve the maximum GBP (>90%) of FW after an 8-day biodigestion in a FWB.

Matched MeSH terms: Bacillus
Enhancing photosynthesis and root development for better fruit quality, aroma, and lessening of radioactive materials in key lime (Citrus aurantifolia) using Trichoderma harzianum and Bacillus thuringiensis

Salem A, Khandaker MM, Mahmud K, Alsufyani SJ, Majrashi AA, Rashid ZM, et al.

Plant Physiol Biochem, 2024 Jan;206:108295.
PMID: 38154296 DOI: 10.1016/j.plaphy.2023.108295

The present study was conducted to investigate the effects of Trichoderma harzianum and Bacillus thuringiensis alone or with gradual levels of NPK on photosynthesis, growth, fruit quality, aroma improvement and reduced radionuclides of key lime fruits. The lemon seedlings were treated with (T0) without fertilizers as control, (T1) 100g of NPK at 100%, (T2) 5 g of Trichoderma. harzianum at 50% + 50 g of NPK at 50%, (T3) 5 g of Bacillus thuringiensis at 50% + 50 g of NPK at 50 %, (T4) 7.5 g of Trichoderma harzianum at 75% + 25 g of NPK at 25 %, (T5) 7.5 g of Bacillus thuringiensis at 75% + 25 g of NPK at 25 %, (T6) 10 g of Trichoderma harzianum at 100 % and (T7)10 g of Bacillus thuringiensis at 100 %. The results showed that T2 increased net photosynthetic rate, stomatal conductance, transpiration rate, internal CO2 concentration, fresh and dry root biomass by 209%, 74%, 56%, 376%, 69.4% and 71.6%, while, T5 increased root volume, root length, and root tip number by 27.1%, 167%, and 67%, respectively over the control trees. The microbial treatments developed cortex, vascular cylinder and tracheal elements of the root. Fruit number, length, diameter, weight, pulp thickness, pulp/peel ratio, juice, total soluble solids (TSS), pigment contents and antioxidant activity increased significantly in the T2 treatment. Vitamin C, total phenols, total flavonoids, and total sugar content increased by 1.59-, 1.66-, 1.44- and 2.07- fold in T5 treated fruits compared to the control. The two microbes increased volatile compounds and decreased radionucleotides in the fruit, moreover, 27 identified and 2 (two) unmatched volatile compounds were identified by GCMS analysis. It is concluded that T. harzianum and B. thuringiensis with 25-50 g NPK treatments improved photosynthesis, root structure, fruit growth, fruit quality, aroma and lessened radionuclides in key lime fruits.

Matched MeSH terms: Bacillus thuringiensis*
Entrapment of porous cross-linked enzyme aggregates of maltogenic amylase from Bacillus lehensis G1 into calcium alginate for maltooligosaccharides synthesis

Nawawi NN, Hashim Z, Rahman RA, Murad AMA, Bakar FDA, Illias RM

Int J Biol Macromol, 2020 May 01;150:80-89.
PMID: 32035147 DOI: 10.1016/j.ijbiomac.2020.02.032

Maltooligosaccharides (MOSs) are emerging oligosaccharides in food-based applications and can be synthesized through the enzymatic synthesis of maltogenic amylase from Bacillus lehensis G1 (Mag1). However, the lack of enzyme stability makes this approach unrealistic for industrial applications. The formation of cross-linked enzyme aggregates (CLEAs) is a promising tool for improving enzyme stability, and the substrate accessibility problem of CLEA formation was overcome by the addition of porous agents to generate porous CLEAs (p-CLEAs). However, p-CLEAs exhibited high enzyme leaching and low solvent tolerance. To address these problems, p-CLEAs of Mag1 (Mag1-p-CLEAs) were entrapped in calcium alginate beads (CA). Mag1-p-CLEAs-CA prepared with 2.5% (w/v) sodium alginate and 0.6% (w/v) calcium chloride yielded 53.16% (17.0 U/mg) activity and showed a lower deactivation rate and longer half-life than those of entrapped free Mag1 (Mag1-CA) and entrapped non-porous Mag1-CLEAs (Mag1-CLEAs-CA). Moreover, Mag1-p-CLEAs-CA exhibited low enzyme leaching and high tolerance in various solvents compared to Mag1-p-CLEAs. A kinetic study revealed that Mag1-p-CLEAs-CA exhibited relatively high affinity towards beta-cyclodextrin (β-CD) (Km = 0.62 mM). MOSs (300 mg/g) were synthesized by Mag1-p-CLEAs-CA at 50 °C. Finally, the reusability of Mag1-p-CLEAs-CA makes them as a potential biocatalyst for the continuous synthesis of MOSs.

Matched MeSH terms: Bacillus/enzymology; Bacillus/metabolism*
Evaluation of Bactimos wettable powder, granules and briquets against mosquito larvae in Malaysia

Sulaiman S, Jeffery J, Sohadi AR, Yunus H, Busparani V, Majid R

Acta Trop, 1990 May;47(4):189-95.
PMID: 1973019

There was high mortality in late larval instars of Aedes albopictus (Skuse) from laboratory and field populations in the 24 h after application of three Bactimos formulations of Bacillus thuringiensis H-14. Mortalities were higher and residual effects longer in field populations than in laboratory ones. Briquets were the most effective formulation (mortality 96-100% after five weeks; 76-92% after eight weeks). Culex quinquefasciatus Say larvae were tested only against the briquet formulation. In the laboratory, 100% mortality of late instars persisted for six weeks and dropped to 48-88% after eight weeks. In the field, late instars were reduced by 62-87% after 24 h and 69-72% after one week compared to increases in an untreated population of 160% and 176% respectively.

Matched MeSH terms: Bacillus thuringiensis*

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