Amylase Production Research Articles

Mycobiota contaminating some market cake samples with reference to their toxin and enzyme

Fungi can spoil the majority of baked products. Spoilage of cake during storage is commonly associated with fungi. Therefore, this study aimed to assess the quality of different types of cakes sold in the market. The most predominant fungal genera in the tested cake samples (14 samples) were Aspergillus spp., and Penicillium spp. On Potato Dextrose Agar (PDA), the medium fungal total count was 43.3 colonies /g. Aspergillus was the most dominant genus and was isolated from six samples of cake. Aspergillus was represented by 3 species namely, A. flavus, A. niger, and A. nidulans, represented by 13.32, 19.99, and 3.33 colonies /g respectively. On Malt Extract Agar (MEA) Medium, the fungal total count was 123.24 colonies / g. Aspergillus was the most dominant isolated genus from 11 samples of cake and was represented by 5 species, namely, A. flavus, A. niger, A. ochraceous, A. terreus, and A. versicolor (26. 65, 63.29, 3.33, 6.66, and 3.33 colonies / g , respectively). Twenty-four isolates (88.88 %) of the total tested twenty-seven filamentous fungi showed positive results for amylase production. Ten isolates (37.03%) of the total tested filamentous fungi showed positive results for lipase production, and finally eleven isolates (40.74 %) of the total fungal isolates showed positive results for protease production. Aflatoxins B1, B2, G1, G2, and ochratoxin A were not detected in fourteen collected samples of cake. In this study, clove oil was the best choice overpeppermint oil and olive oil for preventing mold development when natural agents were compared. It might be due to the presence of a varietyof bioactive chemical compounds in clove oil, whose major bioactive component is eugenol, which acts as an antifungal reagent. Therefore, freshly baked cake should be consumed within afew days to avoid individuals experiencing foodborne illnesses.

Amylase and Cellulase Production from Newly Isolated Bacillus subtilis Using Acid Treated Potato Peel Waste.

Species belonging to the genus Bacillus produce many advantageous extracellular enzymes that have tremendous applications on a commercial scale for the textile, detergent, feed, food, and beverage industries. This study aimed to isolate potent thermo-tolerant amylolytic and cellulolytic bacterium from the local environment. Using the Box-Behnken design of response surface methodology, we further optimized the amylase and cellulase activity. The isolate was identified by 16S rRNA gene sequencing as Bacillus subtilis QY4. This study utilized potato peel waste (PPW) as the biomaterial, which is excessively being dumped in an open environment. Nutritional status of the dried PPW was determined by proximate analysis. All experimental runs were carried out in 250 mL Erlenmeyer flasks containing acid treated PPW as a substrate by the thermos-tolerant Bacillus subtilis QY4 incubated at 37 °C for 72 h of submerged fermentation. Results revealed that the dilute H2SO4 assisted autoclaved treatment favored more amylase production (0.601 IU/mL/min) compared to the acid treatment whereas high cellulase production (1.269 IU/mL/min) was observed in the dilute acid treatment and was found to be very effective compared to the acid assisted autoclaved treatment. The p-value, F-value, and coefficient of determination proved the significance of the model. These results suggest that PPW could be sustainably used to produce enzymes, which offer tremendous applications in various industrial arrays, particularly in biofuel production.

Algal Oil Mitigates Sodium Taurocholate-Induced Pancreatitis by Alleviating Calcium Overload, Oxidative Stress, and NF-κB Activation in Pancreatic Acinar Cells.

Acute pancreatitis (AP) is characterized by elevated intracellular Ca2+ concentrations, mitochondrial dysfunction, and oxidative stress in pancreatic acinar cells. Algal oil (AO) has demonstrated antioxidant and anti-inflammatory properties. This study aims to explore the effects of algal oil on the microenvironment of AP. Rat pancreatic acinar AR42J cells were pretreated with AO containing 0, 50, 100, or 150 μM of docosahexaenoic acid (DHA) 2 h prior to AP induction using sodium taurocholate (STC). After 1 h of STC treatment, AR42J cells exhibited a significant increase in intracellular Ca2+ concentration and the production of amylase, lipase, reactive oxygen species, and pro-inflammatory mediators, including tumor necrosis factor-α and interleukin-6. These STC-induced increases were markedly reduced in cells pretreated with AO. In comparison to cells without AO, those treated with a high dose of AO before STC exposure demonstrated a significant increase in mitochondrial membrane potential and a decrease in lipid peroxidation. Furthermore, STC-activated nuclear factor kappa-B (NF-κB) was attenuated in AO-pretreated cells, as evidenced by a significant decrease in activated NF-κB. In conclusion, AO may prevent damage to pancreatic acinar cells by alleviating intracellular Ca2+ overload, mitigating mitochondrial dysfunction, reducing oxidative stress, and attenuating NF-κB-targeted inflammation.

Genomic insights into Streptomyces hygroscopicus subsp. hygroscopicus SRF1: a potential biocontrol agent against fusarium wilt with plant growth-promoting abilities in tomatoes

ABSTRACT Streptomyces sp. isolate SRF1 has previously demonstrated promising results in controlling various plant fungi under in vitro conditions. However, further exploration of its genome and its efficacy in disease control and plant growth promotion under in vivo conditions is warranted. This study aimed to utilise whole genome sequencing (WGS) to classify Streptomyces sp. isolate SRF1 at the species level and predict genes associated with antagonistic ability and plant growth promotion, thereby assessing its potential as a biocontrol agent against fusarium wilt and a promoter of plant growth. WGS was employed to elucidate the taxonomic classification of isolate SRF1 and predict genes involved in disease suppression and plant growth promotion. In vitro assays were conducted to evaluate its antagonistic activity against Fusarium oxysporum f. sp. lycopersici (Fol) and its production of cellulase, amylase, indole-3-acetic acid (IAA), and siderophores. Pot experiments were carried out using SRF1 cell suspension and culture filtrate to assess its efficacy against Fol and its impact on tomato growth. Real-time PCR analysis was performed to correlate gene expression levels with observed activities. The results showed that isolate SRF1 was classified as S. hygroscopicus subsp. hygroscopicus and demonstrated antagonism against Fol. Furthermore, WGS revealed genes or gene clusters associated with disease control, including those encoding antifungal agents such as butyrolactol A, nigericin, and hygromycin A. Additionally, genes responsible for auxin biosynthesis, siderophore production, and carbohydrate-digesting enzymes such as chitinase, cellulase, and amylase were identified, suggesting potential roles in disease suppression and plant growth promotion.

Determination of Antagonistic Activities of Endophytic Bacteria Isolated from Different Wheat Genotypes Against Fusarium culmorum

This study aimed to evaluate the physiological and biochemical properties and enzyme activities of endophytic bacteria obtained from different wheat genotypes, as well as their effectiveness against Fusarium culmorum, which causes root and crown rot in wheat. The results obtained from double culture tests of isolates against F. culmorum showed that the inhibition rate varied between 80.56% and 13.90%. The inhibition rate against F. culmorum was 80.59% for Bacillus subtilis (MM11), 69.41% for Stenotrophomonas maltophilia (EY5), and 61.10% for Enterobacter sp. (MY3) under in vitro conditions, the most effective isolates. Pseudomonas putida (EM9) and Pseudomonas orientalis (MM21) isolates gave positive results in all tests in the production of amylase, cellulase, phosphatase, ACC deaminase, and siderophore. To identify six promising isolates, 16S rRNA gene-based sequence analysis was utilized. The efficacy of bacterial strains against F. culmorum, pot experiments were conducted in a growth room (in vivo). The results demonstrated that the combination of S. maltophilia, Enterobacter sp., and B. subtilis (MY3+EY5+MM11) yielded the most favorable outcomes in terms of disease severity, plant height, wet weight, dry weight, root wet weight, and root dry weight. The combination of Stenotrophomonas rhizophila, P. putida, and P. orientalis (EY1+EM9+MM21) exhibited promising results. Utilizing effective bacterial strains is anticipated to reduce the dependence on and costs associated with chemical fertilizers and pesticides while minimizing their environmental impact. Furthermore, these strains show potential for commercial applications pending further validation procedures. The findings from this study significantly contribute to the field of biological control strategies against F. culmorum by leveraging the diverse capabilities of endophytic bacteria.

Isolation of Amylolytic Lactic Acid Bacteria from Cow, Goat and Sheep Milk in Yola Town, Adamawa State, Nigeria

In this study, lactic acid bacteria (LAB) were isolated from fresh milk samples from cow, sheep, and goat using MRS agar as a growth medium. Lactobacillusplantarum, Lactobacillusacidophilus, Lactobacillusfermentum, Enterococcusgallinarum, and Enterococcusfaecium were the species of LAB that were isolated and identified using the Vitek 2 compact system. While Lactobacillus fermentum, Enterococcus faecium, and Lactobacillus plantarum were isolated from goat milk, Lactobacillus acidophilus, Lactobacillus gallinarum, and Lactobacillus plantarum were isolated from cow milk.However, from sheep milk, only Lactobacillus plantarum and Lactobacillus acidophilus were isolated. All the isolates were subjected to amylase production test using modified MRS media and the results showed that Lactobacillus plantarum, Lactobacillusacidophilus and Lactobacillusfermentum produced amylase while Enterococcus gallinarum and Enterococcus faecium did not produce amylase.

Production and Optimization of Extracellular α-amylase From Halophilic Bacteria Cytobacillus oceanisediminis Isolated From Wadi-El-Natrun, Egypt

The current study aimed to maximize α-amylase enzyme production by halophilic bacteria Cytobacillus oceanisediminis isolated from soil of Wadi-El-Natrun, Egypt. The results showed that of 21 halophilic bacterial isolates recovered from saline soil samples, eight isolates were high amylase producers. Interestingly, the bacterial isolate AHB6 exhibited the highest extracellular amylase production and was selected for further studies. This isolate was molecularly identified based on the 16srRNA gene sequencing as Cytobacillus oceanisediminis and has the accession number OM759999. The optimum temperature for α-amylase enzyme was 45 °C and exhibited thermostability at 45 °C for 1 h and retained more than 80% of its original activity. The α-amylase enzyme was active in almost all tested pHs and reached its highest activity at pH 9. Also, the optimum culture conditions for α-amylase enzyme production were wheat bran as carbon source, 2 g/l K2HPO4 as potassium source, 6 g/l MgSO4 as magnesium source and 0.5 g/l KNO3 as nitrogen source. These findings suggest the applicability of bacterial isolate Cytobacillus oceanisediminis as a potent producer of α-amylase for industrial purposes. Keywords: Amylase; Optimization; Cytobacillus oceanisediminis; Starch hydrolysis; Thermo-halophilic bacteria.

Nutritional and Molecular Studies of Alkaliphilic Tolerant Potential Amylase Producing Lactic Acid Bacteria Isolated from Indigenous Foods and Dumpsites

Alkaliphilic organisms are important in industries but most of these organisms are obtained from Bacillus species and the like that require special scrutiny before use in fermentation of food related products. Lactic acid bacteria are generally regarded as safe (GRAS) and are therefore readily applied in industrial fermentation with confidence. Due to high demand for the products of alkaliphilic organisms and industrial acceptability of lactic acid bacteria, there is a need to source for GRAS microorganisms that can withstand pH ranges. The aim of this study was to isolate alkaliphilic tolerant lactic acid bacteria from fermented cassava mash, `ogi` and dump site samples with a view to determining their nutritional requirement as well as molecular identity. Lactic acid bacteria were isolated from the samples using standard methods. The isolates were subsequently characterized morphologically, biochemically and molecularly. Effects of different carbon, nitrogen sources, initial temperature and pH as well as metal ions (Na+, Ca2+, Mg2+, Zn2+ and Cu2+) on the growth of the isolates were examined. Data obtained were analyzed using one-way analysis of variance (ANOVA). Results obtained indicate that extracted DNA sequence of A3, A7, A8 and A10 were related to those of Lactobacillus brevis FJ476121.1, Pediococcus acidilactici CP096031.1, Pediococcus pentasaceus AB362605.1 and Pediococcus acidilactici CP053421.1 respectively with the sequences within the GenBank. 1% fructose elicited growth for all the bacteria detected except Lactobacillus brevis and ammonium nitrate was most preferred by all the bacteria detected apart from Pediococcus pentasaceus strain. Lactobacillus brevis FJ476121.1 and Pediococcus acidilactici CP053421.1 were the most alkaliphilic tolerant bacteria detected with OD of 0.285±0.04 and 0.198±0.04 respectively. Different metal ions significantly influenced the growth of isolates in this study. The results in this study indicate potential applicability of the detected bacteria for industrial processes.

Biochemical Characterization of Microsymbionts Associated with Zornia gibbosa Span. in Central Aravalli Range

In current scenario, with increasing world population there is a strong demand to enhance crop productivity to feed the population. Characterization of indigenous rhizobia is very crucial for developing biofertilizers tailored to local climatic conditions, with the goal of increasing food production without excess use of chemical fertilizers. In the present investigation 44 root nodule bacterial strains or microsymbionts were isolated from root nodules of Zornia gibbosa growing in Central Aravalli region. These isolated RNB strains were examined for their phenotypic and biochemical activities such as salt tolerance, pH tolerance, bromo thymol blue (BTB) reaction, catalase activity, oxidase activity, cellulase activity, amylase production, indole production, citrate utilization and gelatin hydrolysis. All tested isolates showed significant diversity in their phenotypic and biochemical activities. The majority of the strains were limited to a tolerance of up to 3% NaCl concentration; however, strains Z2, Z13, Z14, Z15, Z21, and Z22 demonstrated tolerance up to a 5% NaCl concentration. A total of 29 isolates were able to grow within the pH range of 5-10. Few isolates showed positive results for citrate utilization (Z4, Z18, Z22, Z32 and Z44) and amylase production (Z4, Z6, Z21, Z25 and Z42). In this study only one isolate Z22 showed indole production. Conversely, when assessing various enzyme activities such as cellulase, catalase, protease, and gelatinase, all the isolates demonstrated considerable diversity. This type of study is essential for developing superior biofertilizers containing indigenous bacterial strains to enhance production.

Isolation and Identification of Soil-Derived Amylase-Producing Bacteria

Soil is a vital ecosystem for various life forms, including bacteria. Bacteria are the main group of soil microbes, mostly because of their ability to produce various extracellular enzymes. Amylases are the enzymes that break down starch, which are essential in biotechnology industries such as food, fermentation, textiles, and paper manufacturing. The demand for amylase is often high since many enterprises do not have access to local supplies of the enzyme. The objective of the current investigation is to isolate and identify bacterial isolates that can produce the enzyme amylase from soil samples. Soil samples were collected from the unexplored Biligiriranga hills (11.9988° N, 77.1398° E) in south-western Karnataka Bacterial isolates were isolated from soil samples and were primarily screened on starch agar medium to determine the amylase production. Three out of fifteen bacterial isolates that produced amylase were selected based on the highest clear zone around the bacterial colony. These three bacterial isolates were identified both microscopically and biochemically. Gram staining demonstrated that the isolates are rod-shaped and gram-positive organisms. Biochemical studies indicated that the isolates were positive for the catalase and starch hydrolysis tests, whereas negative for the potassium hydroxide and methyl red tests. Besides, 16S rRNA gene amplification and sequencing confirmed the isolate as Bacillus subtilis. The 16S rRNA sequence of B. subtilis strain B has been deposited in the NCBI GenBank. The optimal growth conditions observed in B. Subtilis. The optimal growth conditions observed in B. Subtilis were 37° C temperature at pH 7 and incubation period for 37h. Thus, the isolation and identification of soil-derived amylase-producing bacteria are crucial for understanding their potential applications in various industrial processes, such as bioremediation, waste management, and the production of enzymes for food, pharmaceuticals, and biofuel industries.

The evaluation of next-generation probiotics on broiler growth performance, gut morphology, gut microbiome, nutrient digestibility, in addition to enzyme production of Bacillus spp. in vitro

Considerable research has been conducted into the efficacy of individual probiotics in broiler production, however information on the most effective combinations of synergistic Bacillus probiotic is lacking. This study investigated the impact of different Bacillus strain combinations in broiler chickens, as well as in vitro enzyme production. In experiment one, a total of 576 Ross 308 broilers at 1 d old were grown for 21 d across 6 treatments of maize-soybean diets (n = 12 pens per treatment) to compare three different strain combinations (formulation 1 [F1]: 3 strains Bacillus amyloliquefaciens; F2: Bacillus coagulans and 2 strains B. amyloliquefaciens; F3: B. coagulans, Bacillus licheniformis and 2 strains B. amyloliquefaciens; F5: Bacillus subtilis, B. licheniformis and 2 strains B. amyloliquefaciens), positive control (PC), and a negative control antibiotic treatment group (NC). In Exp. 2, a total of 360 one-day-old ROSS308 broilers were used to test five treatments (n = 9) including PC, NC, F1 and F5 (selected from Exp. 1), and F4 (Bacillus pumilis and 2 strains B. amyloliquefaciens) in a maize-soybean diet. B. amyloliquefaciens F1 demonstrated a significant improvement in feed conversion ratio (FCR) compared to F2 at d 14 (1.49 vs 2.10; P = 0.038) and the body weight (BW) at d 21 (847.0 g vs 787.4 g) compared to other combinations (P = 0.027). The FCR at d 21 tended to be lower in birds fed F1 (1.46 vs 1.66) compared to the control (P = 0.068). Probiotic treatments had significantly improved nutrient digestibility compared to the PC and NC. Also, probiotic treatments supported the growth of Streptococcus, a common commensal genus and reduced the abundance of genera that correlated with low weight gain such as Akkermansia. Experiment two revealed that F4 improved FCR (P < 0.001) and BW at 28 d (P = 0.014). In vitro testing showed a high production of protease and amylase by Bacillus. Thus, the addition of Bacillus probiotics, particularly containing B. amyloliquefaciens strains and Bacillus pumilus, into the diet of broiler chickens improves production performance, nutrient digestibility, and allows the proliferation of beneficial gut microbiota.

Response surface methodology as an approach for optimization of alpha amylase production by using bacterial consortium under submerged fermentation

The present study aims to isolate amylolytic bacteria and later the formation of a bacterial consortium for alpha-amylase production. The potent amylolytic strains in a selected consortium were identified as B. subtilis and B. licheniformis on the basis of 16S rRNA sequencing. Initially cultural conditions for alpha amylase were optimized in Plackett–Burman design, followed by the central composite design. Analysis of Variance (ANOVA) of the optimization study indicated pH 7, 0.05 %CaCl2 and 24 h incubation time were the significant variables that mainly effect the alpha amylase production. After the process of statistical optimization, the enzyme was then partially purified by means of ammonium sulfate precipitation at a 60% saturation level, resulting in a 2-fold purification with 1.4 U/mg specific activity. Enzyme kinetics studies showed that the maximum velocity of the reaction (Vmax) and Michaelis constant (Km) were 47.4 mg/ml and 13.2 mM, respectively. Current results suggest the newly isolated bacterial consortium could be considered as a promising candidate for industrial applications.

Optimization of the Production Process of Clinical-Grade Human Salivary Gland Organoid-Derived Cell Therapy for the Treatment of Radiation-Induced Xerostomia in Head and Neck Cancer.

Head and neck cancer is a common cancer worldwide. Radiotherapy has an essential role in the treatment of head and neck cancers. After irradiation, early effects of reduced saliva flow and hampered water secretion are seen, along with cell loss and a decline in amylase production. Currently, there is no curative treatment for radiation-induced hyposalivation/xerostomia. This study aimed to develop and optimize a validated manufacturing process for salivary gland organoid cells containing stem/progenitor cells using salivary gland patient biopsies as a starting material. The manufacturing process should comply with GMP requirements to ensure clinical applicability. A laboratory-scale process was further developed into a good manufacturing practice (GMP) process. Clinical-grade batches complying with set acceptance and stability criteria were manufactured. The results showed that the manufactured salivary gland-derived cells were able to self-renew, differentiate, and show functionality. This study describes the optimization of an innovative and promising novel cell-based therapy.

A multifaceted analysis of spent mushroom substrate of selected oyster mushrooms for enzymatic activity, proximate composition, and antimicrobial activity

The global market for mushrooms is growing due to its nutritional enrichment, potential usage as a bioremediation, enzyme production, and functional food development. However, the leftover post-harvest mushroom substrate (SMS) generates certain environmental concerns. This study aimed to investigate the potential of SMS obtained from two oyster mushroom species—Pleurotus ostreatus and Pleurotus djamor. These were examined regarding sustainability by analyzing their lignocellulosic enzyme production, cellulose yield, antimicrobial properties, and proximate composition. The findings for both P. ostreatus and P. djamor showed higher activity of amylase, that is, 0.3 U (μmol/min) and 0.7 U (μmol/min), respectively, compared to activity of cellulase, which showed 0.3 U (μmol/min) and 0.5 U (μmol/min), respectively. SMS showed the highest activity of lignocellulosic enzymes, compared to non-SMCs and controls at p ≤ 0.00 and ≤0.01), proving fungual mycelia as the precursor of enzymes activity, as no mushroom is cultivated due to least enzymatic activity. The results for proximate analysis of SMCs showed a significant difference from non-SMCs. The findings for P. djmor revealed protein (1.23%), fats (1.3%), and ash (8.11), which were significantly higher than in P. ostreatus. A positive co-relation of 52% was established between SMCs with amylase, while a correlation of 20% was observed with cellulase, depicting an impact of mycelia in the breakdown of protein for amylase production. The SMC samples were also subjected to antibacterial analysis against Staphylococcus aureus, E. coli, and Xanthomonas. A higher minimum inhibition concentration (MIC) was recorded for P. djamor, that is, 8.80 mm, 11.66 mm, and 9.04 mm, compared to P. ostreatus, which showed its highest MIC as 9.18 mm, 9.30 mm, and 9.28 mm for S. aureus, E. coli, and Xanthomonas, respectively. It was evident from the study that SMC has a potential of being utilized for bioremediation, as it is therapeutically active against pathogens. Additionally, Pleurotus spp. is of great interest because of its ability to produce high nutritive value, cellulose yield, and a vast amount of lignocellulosic enzymes. The current experiment recommends the use of distilled water for mushroom farming, as enzymatic activities can significantly be affected by pH and buffers. Furthermore, the spent compost, being rich nutritionally, can be used for soil enrichment or as a biofertilizer.

Screening the Rumen of Balochi Camel (Camelus dromedarius) and Cashmere Goat (Capra hircus) to Isolate Enzyme-Producing Bacteria as Potential Additives for Animal Feed.

Rumen microbiology has made a significant contribution to the discovery of biodegradation processes, which convert nutrients into energy for ruminants. Therefore, understanding the enzymatic potential in the rumen of different animal species is essential for developing efficient microbial feed additives. The aim of this study was to isolate enzyme-producing bacteria (EPBs) from the rumen of the Balochi camel (Camelus dromedarius) and Cashmere goat (Capra hircus) as potential additives for animal feed. The EPBs were screened based on the hydrolysis of carboxyl methyl cellulose, tannin, starch, and bovine serum albumin. The isolates were then subjected to enzyme activity assays and molecular characterization. Additionally, they were evaluated for their antagonistic effects, antibiotic susceptibility, and growth in acidic, bile, and saline media. Thirteen enzyme-producing strains were identified in the rumen of the camels and goats, belonging to the genera Klebsiella, Escherichia, Raoultella, Enterobacter and Pectobacterium. The highest and lowest tannase activities were recorded for Escherichia coli GHMGHE41 (10.46Um/l-1) and Raoultella planticola GHMGHE15 (1.83Um/l-1), respectively. Enterobacter cloacae GHMGHE18 (2.03U/ml) was the most effective cellulolytic isolate, compared to Klebsiella strains (1.05Um/l-1). The highest protease producer was Klebsiella pneumoniae GHMGHE13 (3.00U/ml-1), while Escherichia coli GHMGHE17 (1.13U/ml-1) had the lowest activity. Klebsiella pneumoniae GHMGHE13 (1.55U/ml-1) and Enterobacter cloacae GHMGHE19 (1.26U/ml-1) were the highest and lowest producers of amylase, respectively. The strains exhibited mixed responses to antibiotics and remained stable under stressful conditions. These findings indicate that ruminal EPBs have the potential to be used in animal feed, pending further in vivo studies.

Characterization and Identification of Thermophilic Bacteria Isolated from Different Sites Located in Al-Jouf Region, Saudi Arabia

This study aims to investigate the morphological and biochemical characteristics of thermophilic bacteria isolated from thermophilic biotopes in the Al-Jouf region of Saudi Arabia for the first time. Additionally, the production of thermostable bacterial enzymes (proteases, amylases, cellulases, gelatinases, and lipases) was investigated. Six main bacterial species were identified via 16S rRNA sequencing and phylogenetic analysis. Twenty water and soil samples were collected from several thermophilic sites in the Dumat Al-Jandal and Al-Qurayyat cities. In total, 28 bacterial strains were isolated and biochemically characterized. Most isolated strains showed high protease and amylase production. 46 and 28% of isolated strains showed the production of cellulase and gelatinase, respectively. However, lipase production was not observed in any isolated bacteria. Four Bacillus licheniformis and two Bacillus subtilis strains exhibited high GC content (55%). Our findings suggest thermophilic bacteria as a source of thermostable enzymes for pharmaceutical and industrial applications.

Screening and characterization of thermostable enzyme-producing bacteria from selected hot springs of Ethiopia.

Thermostable microbial enzymes play an important role in industries due to their stability under harsh environmental conditions, including extreme temperatures. Despite their huge application in different industries, however, the thermostable enzymes of thermophilic microorganism origin have not yet been fully explored in Ethiopia. Here, we explored thermophilic bacteria and their enzymes from selected hot spring water and sediment samples. Accordingly, thermophilic bacteria were isolated and screened for the production of extracellular hydrolytic enzymes. Promising numbers of isolates were found as producers of the enzymes. The potent enzyme producers were further identified using matrix-assisted laser desorption/ionization time-of-flight-mass spectrometry analysis and 16S rRNA gene sequencing. The findings revealed the presence of potential hydrolytic enzyme-producing thermophilic bacteria in hot springs of Ethiopia and necessitate further comprehensive study involving other extreme environments. Our findings also revealed the potential of Ethiopian hot springs in the production of thermostable enzymes of significant application in different industries, including food industries.

Screening and characterization of endophytic bacteria isolated from celery with the potential to promote plant growth

Abstract. Nuriyanah, Widowati T, Masnang A, Nurjanah L, Novilasari D, Lekatompessy SJR, Simarmata R. 2023. Screening and characterization of endophytic bacteria isolated from celery with the potential to promote plant growth. Biodiversitas 24: 6897-6904. Endophytic bacteria that inhabit plant tissue contribute to the enhancement of host plant growth by producing secondary metabolites. They can improve plant growth by phytohormone modulation and nutrient uptake. In addition, endophytic bacteria can increase plant health and tolerance by antibiotic and hydrolytic enzyme production. This study aims to screen and characterize endophytic bacteria of celery as plant growth promoter agents. Thirty endophytic bacteria were isolated successfully from part of the celery plant using the spread plate and plant piece method which grew at Nutrient Agar media. Based on the characterization assay, 30 isolates may produce IAA with various concentrations of 0.21-7.18 mg/L. In addition, 3 of 30 isolates had phosphate solubilizing activity, in different indexes ranging from 0.71-1.43. Twenty-one isolates were able to grow in an N-free medium, indicating the capability of isolates to fix nitrogen qualitatively. The hydrolytic enzymes assay resulted in 14 amylolytic, 17 proteolytic, and 12 cellulolytic activities. In addition, nine of 30 isolates show multi-activity in amylase, protease, and cellulase enzyme production. Based on the screening results, there are four potential isolates (SLBg 1.2; SLBg 1.5; SLAg 1.1, and SLAg 1.5) as promising plant-growth promoters and were molecularly identified as members of the Bacillus genus. These isolates can be developed as biofertilizers for supporting the cultivation of celery plants.

Statistical Optimization of α-Amylase Production from Novel Local Isolated Bacillus spp. NRC1 and Its Textile Applications

By employing Plackett–Burman design (PBD) to investigate the qualitative interactions between eleven parameters [potato shell weight, incubation time, glucose, lactose, baker's yeast, peptone, (NH4)2SO4, CuSO4, FeSO4, CaCl2, KCl], and central composite design (CCD), the production of α-amylase by a local bacterial isolate Bacillus spp. NRC1 using agro-industrial wastes was improved. Using a variety of waste materials, including corn cobs (CC), onion peels (OP), rice straw (RS), potato shells (PS), Molokhia stem (MS), okra suppression (OS), lemon peels (LP), and pea peels (PP), Bacillus spp. NRC1 was tested in the production of amylase. Out of the eight agro-industrial wastes tried, the highest amylase yield (6.99 U/ml) was reached using potato peels. The statistical optimization of enzyme production was carried out using PBD followed by CCD design, causing 2.06-fold and 1.51-fold increase, respectively. The overall increase was 3.11-fold. In PBD design, potato peels, peptone and (NH4)2SO4 were positive factors for amylase production. The crude enzyme was tested for its ability to desize cotton fabric and subsequently studying its effect on fabric dyeability. The produced amylase proved its potentials in textile industry.Graphical

Linkage-Editing Pseudo-Glycans: A Reductive α-Fluorovinyl-C-Glycosylation Strategy to Create Glycan Analogs with Altered Biological Activities.

The acetal (O-glycoside) bonds of glycans and glycoconjugates are chemically and biologically vulnerable, and therefore C-glycosides are of interest as more stable analogs. We hypothesized that, if the O-glycoside linkage plays a vital role in glycan function, the biological activities of C-glycoside analogs would vary depending on their substituents. Based on this idea, we adopted a "linkage-editing strategy" for the creation of glycan analogs (pseudo-glycans). We designed three types of pseudo-glycans with CH2 and CHF linkages, which resemble the O-glycoside linkage in terms of bond lengths, angles, and bulkiness, and synthesized them efficiently by means of fluorovinyl C-glycosylation and selective hydrogenation reactions. Application of this strategy to isomaltose (IM), an inducer of amylase expression, and α-GalCer, which activates iNKT cells, resulted in the discovery of CH2-IM, which shows increased amylase production ability, and CHF-α-GalCer, which shows activity opposite that of native α-GalCer, serving as an antagonist of iNKT cells.