Fungal Screening and Isolation of Cellulolytic, Mannan and Protein Degrading Enzyme Producers in Palm Kernel Cake Solid State Fermentation

Palm Kernel Cake (PKC), an agro-industrial by-product obtained after extraction of oil palm from oil palm seeds is used extensively in the animal feed industry but has limited used in poultry feed due to its high fiber and low protein contents. In this study, PKC was used as a substrate in solid state fermentation (SSF) by locally-isolated strains and their feasibility for cellulase and mannanase enzymes production were investigated. The potential isolates were obtained from various sources such as peat soil, rotten rice chaff, ‘Tanah Bakar’, rotten palm frond and raw PKC. The isolates were screened based on the clearing zone method and on selective agar media containing substrates such as locust bean gum (LBG), carboxymethylcellulose (CMC), potato dextrose, mannan and PKC. Forty-eight fungal cultures have been screened and isolated based on the selective agars. Only thirty-one isolates were able to grow well after multi-subculturing techniques. The microbial activities of the isolates were accessed through clearing zone by chromogenic substrates such as Azo-carob galactomannan and Azo-CM cellulose. The diameter of clearing zone on the agar plate was observed every 24 h until 120 h. Cultivation of the strains was carried out at 50% moisture content using shake flask and pre-germinated spores were preferred as the inoculum. The effects of cultivation conditions such as moisture level, inoculum concentration and agitation were investigated with the aim to achieve maximum production of cellulase and mannanase enzymes. Shaking at 120 rpm was found as the best agitation speed in the pre-germination process to be used as the inoculum. The samples were analyzed for neutral detergent fiber, acid detergent fiber, crude fiber and crude protein using Near Infrared Reflectance Spectroscopy analysis. The best enzymes producer was fungal isolate D1 with specific enzyme exoglucanase activity of 17.9323 U/mg, specific enzyme endoglucanase activity of 41.6008 U/mg and specific enzyme β–glucosidase activity of 79.2626 U/mg using the pre-optimized conditions on the fifth day of fermentation process. About 50.1036 U/mg of specific enzyme mannanase activity was achieved on the fourth day of fermentation process using PKC as the substrate. The fibre degradation increased significantly. Neutral and acid detergent fibers were reduced from 85.16 to 21.72% on the sixth day and 45.18 to 17.18% at eighth day of fermentation process, respectively. The protein content increased from 13.31 to 31.53% on the eighth day. Lower cellulase and mannanase enzymes activities were obtained in other isolates. The highest cellulolytic and mannan-degrading enzymes producer was identified using microscopic. Under the microscopic view, isolate D1 was identified as Aspergillus sp. The identity of the isolate was further confirmed and belongs to Aspergillus sp. after observation under Scanning Electron Microscope (SEM). As a result, isolate D1 was identified as Aspergillus sp

Isolation and characterization of caffeine-degrading bacteria from coffee plantation areas in Malaysia

Decaffeination by microbial degradation is currently the most optimal and low-cost approach, involving only microbial cells and/or their enzymes. The bacterium was characterized using a series of biochemical tests. Positive results were obtained from carbohydrate fermentation, citrate utilization, and catalase tests, while negative results were obtained from Voges-Proskauer (VP) and indole tests. Three different caffeine concentrations of 0.25%, 0.4%, and 2% were tested and measured through Gas Chromatography-Mass Spectrophotometry (GC-MS) analysis. The highest caffeine reduction (89.25%) was found when 0.25% caffeine was used in the media. Only a small amount of caffeine was reduced to 0.4% and 2%, with 34.78% and 46.16%, respectively. Under microscopic observation, the shape of the isolated bacteria was rod bacilli and was stained with a pink color, which indicates Gram-negative bacteria. Comparing the results with previous research and observing the color of the pure culture, which revealed a yellow color, bacteria isolated from the coffee plantation area can be concluded to be a partially identified Pseudomonas sp

Magnesium Sulphate and β-Alanine Enhanced the Ability of Kluyveromyces marxianus Producing Bioethanol Using Oil Palm Trunk Sap

The abundance of oil palm trunk waste generated each year has encouraged research in using its sap for fermentation to produce value-added products. One of these value-added products is bioethanol production using yeast strains. In this study, the ability of Kluyveromyces marxianus ATCC 46537 to produce bioethanol using oil palm trunk sap (OPTS) was examined. The nutrients (ammonium sulphate, di-ammonium hydrogen phosphate, magnesium sulphate, b-alanine, calcium chloride and potassium dihydrogen phosphate) required to enhance production were screened and optimised. The concentrations of bioethanol and sugars were monitored with high performance liquid chromatography. The results showed that K. marxianus could attain maximum bioethanol concentration at 16 h with a higher productivity as compared to S. cerevisiae. Magnesium sulphate and b-alanine were found to increase bioethanol production. When 7.93 g/L of magnesium sulphate and 0.90 g/L of b-alanine were supplemented to OPTS, bioethanol production increased 20% with a bioethanol yield of 0.47 g/g and a productivity of 2.22 g/L.h. Therefore, minimum supplementation of OPTS with inorganic nutrients could enhance the bioethanol production of Kluyveromyces marxianus

Preliminary assessment on pretreatment methods for landfill waste utilization in biohydrogen production

Landfill waste consists of a mixture of components that have high potential as a substrate for hosting various microorganisms’ growth. Utilizing this waste as a fermentation substrate is seen as an economical solution for the management of the waste. Treating this waste is crucial to remove unnecessary components for the growth of specific organisms to ensure a high reaction yield. Fermentative hydrogen production from this waste specifically requires the hydrogen-consuming bacteria to be reduced. In this work, heat, ultraviolet (UV) radiation, acid, and alkaline pretreatment were conducted on the landfill waste. The changes in the reduced sugar content and appearance of bacterial colonies were observed and compared. Heat pretreatment at 65 °C was found to give among the best increase (74 – 88%) in reducing sugar content and reduction (50 – 85%) in the number of aerobic bacterial colonies detected. Global warming potential and eutrophication potential recorded from simulated heat pretreatment plant was comparable to other heat-based pretreatment reported by other researchers with a potential reduction in severity as the plant size increased

Preliminary assessment on pretreatment methods for landfill waste utilization in biohydrogen production

Landfill waste consists of a mixture of components that have high potential as a substrate for hosting various microorganisms’ growth. Utilizing this waste as a fermentation substrate is seen as an economical solution for the management of the waste. Treating this waste is crucial to remove unnecessary components for the growth of specific organisms to ensure a high reaction yield. Fermentative hydrogen production from this waste specifically requires the hydrogen-consuming bacteria to be reduced. In this work, heat, ultraviolet (UV) radiation, acid, and alkaline pretreatment were conducted on the landfill waste. The changes in the reduced sugar content and appearance of bacterial colonies were observed and compared. Heat pretreatment at 65 °C was found to give among the best increase (74 – 88%) in reducing sugar content and reduction (50 – 85%) in the number of aerobic bacterial colonies detected. Global warming potential and eutrophication potential recorded from simulated heat pretreatment plant was comparable to other heat-based pretreatment reported by other researchers with a potential reduction in severity as the plant size increased

Probiotic growth pattern and physicochemical evaluation of water kefir fermentation

Probiotics are live-friendly microorganisms that can confer a health benefit on the host if it is consumed in sufficient amounts. Water kefir is a probiotic-rich fermented beverage that contains multi-species of live cultures. Brown sugar and palm sugar were used for water kefir fermentation due to their high sucrose and mineral contents. The objective of this study was to determine the probiotic growth pattern of water kefir and to evaluate the physicochemical parameters, including the pH changes, lactic acid content, reducing sugar content, and total soluble solids. The fermented water kefir was collected at every 6-hour interval, until the end of 72 hours of fermentation. The growth curve was determined by enumerated probiotics on De Man, Rogosa, and Sharpe (MRS) agar, Yeast ExtractPeptone-Dextrose (YPD) agar, and Gluconobacter (GM) agar plates, respectively. MRS, YPD, and GM agar plates were used to enumerate lactic acid bacteria, yeast, and acetic acid bacteria, respectively. The result showed increased probiotic growth as fermentation time increased with different phases observed from the growth curve. The stationary phase of probiotics was recorded at 30-42 h and was recommended as the optimal harvesting point. Besides, longer fermentation time produced lower pH values and lower total soluble solids while higher lactic acid and higher reducing sugars. At the end of fermentation, the concentration of lactic acid and reducing sugars were 2.16 ± 0.09 g/L and 13.66 ± 0.14 mg/mL, respectively. In conclusion, probiotics from water kefir fermentation are suggested to be best harvested between 30-42 hours and can be used for self-consume or downstream processing

Evaluation of pre-treated healthcare wastes during COVID-19 pandemic reveals pathogenic microbiota, antibiotics residues, and antibiotic resistance genes against beta-lactams

The disposal of healthcare waste without prior elimination of pathogens and hazardous contaminants has negative effects on the environment and public health. This study aimed to profile the complete microbial community and correlate it with the antibiotic compounds identified in microwave pre-treated healthcare wastes collected from three different waste operators in Peninsular Malaysia. The bacterial and fungal compositions were determined via amplicon sequencing by targeting the full-length 16S rRNA gene and partial 18S with full-length ITS1–ITS2 regions, respectively. The antibiotic compounds were characterized using high-throughput spectrometry. There was significant variation in bacterial and fungal composition in three groups of samples, with alpha- (p-value = 0.04) and beta-diversity (p-values <0.006 and < 0.002), respectively. FC samples were found to acquire more pathogenic microorganisms than FA and FV samples. Paenibacillus and unclassified Bacilli genera were shared among three groups of samples, meanwhile, antibiotic-resistant bacteria Proteus mirabilis, Enterococcus faecium, and Enterococcus faecalis were found in modest quantities. A total of 19 antibiotic compounds were discovered and linked with the microbial abundance detected in the healthcare waste samples. The principal component analysis demonstrated a positive antibiotic-bacteria correlation for genera Pseudomonas, Aerococcus, Comamonas, and Vagococcus, while the other bacteria were negatively linked with antibiotics. Nevertheless, deep bioinformatic analysis confirmed the presence of blaTEM-1 and penP which are associated with the production of class A beta-lactamase and beta-lactam resistance pathways. Microorganisms and contaminants, which serve as putative indicators in healthcare waste treatment evaluation revealed the ineffectiveness of microbial inactivation using the microwave sterilization method. Our findings suggested that the occurrence of clinically relevant microorganisms, antibiotic contaminants, and associated antibiotic resistance genes (ARGs) represent environmental and human health hazards when released into landfills via ARGs transmission

FIST's postgraduates during the 6th UMP convocation

OCT 10, GAMBANG : UMP's 6th Convocation was held on 1st October 2.011 at UMP's Sports Complex which witnessed 1 ,2.90 graduates receiving their doctoral, master and bachelor degrees and diplomas

Biosensor technology

Biosensor ia an analytical device..

Prevalence of antibiotic resistance in E. coli in leachate

Landfill is one of the common practices for the disposal of municipal solid waste and may include possible contaminants such as antibiotics and heavy metals. The leachate produced from landfill has the potential to become a reservoir of antibiotic residues and heavy metals, leading to the dissemination of antibiotic resistance to the nearby environment. Not only that, enteric bacteria like Escherichia coli (E. coli) may be exposed to these contaminants. E. coli tended to survive in such stressful conditions due to the activation of the stress response. Therefore, this study was conducted to investigate the antibiotic susceptibility of E. coli in leachate. The E. coli was isolated in a landfill in Jabor, Kuantan, Pahang from three sampling points which were garbage hill, leachate pond, and river. The concentration of heavy metals was analyzed using ICP-MS while the antibiotic susceptibility test was performed using the disc diffusion method. Four out of six parameters measured have exceeded the standard permitted range where TSS was 110–580 mg/mL, BOD was 28–176 mg/mL, COD was 447–5100 mg/mL and NH3-N was 9–22 mg/mL. There were five elements (chromium, zinc, copper, manganese, and iron) were detected in leachate where the concentration of iron was the highest (0.158 ± 0.0203–2.287 ± 0.0706 mg/mL) among all metals measured. Besides, the colonies of E. coli were successfully isolated from each sampling point. In this study, all isolated E. coli from garbage hill and leachate pond show resistance towards three antibiotics tested (sulfamethoxazole, tetracycline, and erythromycin). However, isolated E. coli from the river shows intermediate sensitivity to sulfamethoxazole but is resistant to tetracycline and erythromycin. Based on the results, we can conclude that the landfill has the potential to retain pollutants such as TSS, COD, BOD, NH3-N, and antibiotic resistance even though the concentration of heavy metals decreased and meet the standard permitted limit. It shows that the landfill and leachates may act as an important reservoir of heavy metals and antibiotic resistance and potentially affect the environment