Colony Shape Research Articles

Isolation and Macroscopic Characterization of Molase and Alginate Bacteria from Mangrove Sediments in Shrimp Ponds

Bacteria are microscopic organisms capable of thriving in various environments that support their growth, including mangrove sediment. Bacterial characteristics in mangrove sediment were examined using two different media: molasses and alginate. This process included preparing solid media, diluting sediment samples, isolating bacteria, and characterizing isolates. On molasses media (both Molasses Media I and Molasses Media II), bacteria generally displayed entire, undulate, and lobate margins, with diverse shapes (round, irregular, punctiform, rhizoid), colors (opaque, clear), and elevations (convex, flat, umbonate). On alginate media (Alginat Media I and Alginat Media II), after repetition, bacteria typically had entire and lobate margins, varied shapes (round, irregular, punctiform, rhizoid), colors (opaque, clear), and elevations (convex, flat, umbonate). Bacterial isolation utilized the spread plate technique on solid agar media, revealing higher colony growth on molasses media due to richer nutrients compared to alginate. Colony counts were determined via serial dilution, and bacteria displayed diverse macroscopic traits, evaluated using a comparison table considering colony margin, color, elevation, texture, and shape.

IN VITRO STUDY OF PHYLLOSPHERE BACTERIA AS PROMISING BIOCONTROL AGENTS AGAINST BACTERIAL LEAF BLIGHT DISEASE (Xanthomonas oryzae pv. oryzae) IN RICE PLANTS

This study aimed to explore the potential of phyllosphere bacterial isolates as biological control agents against Xanthomonas oryzae pv. oryzae (Xoo). We isolated a strain exhibiting typical morphological and biochemical characteristics of Xoo, such as a yellowish, spherical colony, Gram-negative, and starch hydrolyzing ability. This isolate was shown to cause necrotic lesions on rice leaves, corroborating its pathogenic nature. Subsequently, we isolated ten diverse phyllosphere bacteria from rice plants. These isolates were characterized based on various morphological and biochemical attributes including colony shape, margin appearance, color, growth time, and the ability to fluoresce under UV light when cultivated on King's B medium. Crucially, none of these isolates induced a hypersensitive response in tobacco leaves, an initial indicator of their potential as safe biological control agents. In an antagonistic assay against Xoo, all the phyllosphere isolates demonstrated varying levels of inhibition, suggesting their potential role in biological control. Two isolates, PGM1 and PGM4, exhibited the highest antagonistic effects against Xoo. These findings provide preliminary evidence for the potential use of these phyllosphere isolates in managing bacterial leaf blight in rice, warranting further research to confirm their efficacy and safety under field conditions.

Infection of postharvest pear by Penicillium expansum is facilitated by the glycoside hydrolase (eglB) gene

The primary reason for postharvest loss is blue mold disease which is mainly caused by Penicillium expansum. Strategies for disease control greatly depend on the understanding of mechanisms of pathogen-fruit interaction. A member of the glycoside hydrolase family, β-glucosidase 1b (eglB), in P. expansum was significantly upregulated during postharvest pear infection. Glycoside hydrolases are a large group of enzymes that can degrade plant cell wall polymers. High homology was found between the glycoside hydrolase superfamily in P. expansum. Functional characterization and analysis of eglB were performed via gene knockout and complementation analysis. Although eglB deletion had no notable effect on P. expansum colony shape or microscopic morphology, it did reduce the production of fungal hyphae, thereby reducing P. expansum's sporulation and patulin (PAT) accumulation. Moreover, the deletion of eglB (ΔeglB) reduced P. expansum pathogenicity in pears. The growth, conidia production, PAT accumulation, and pathogenicity abilities of ΔeglB were restored to that of wild-type P. expansum by complementation of eglB (ΔeglB-C). These findings indicate that eglB contributes to P. expansum's development and pathogenicity. This research is a contribution to the identification of key effectors of fungal pathogenicity for use as targets in fruit safety strategies.

Isolation, morphological characterization, and screening a virulence of Beauveria bassiana and Metarhizium robertsii as bioagents

Background: Entomopathogenic fungi exists naturally in plants as an asymptote and has the potential to reduce the population of insect pests through indirect interactions. This study was conducted to detect and characterize the endophytic fungi Beauveria bassiana and Metarhizium robertsii from the rhizosphere soil of tomato plants and their virulence effect on Galleria melonella. Methods: From the rhizosphere soil of 40 tomato fields, three Beauveria bassiana and seven Metarhizium robertsii isolates were identified using the galleria bait method. All fungi isolates were morphologically characterized by their colony color, shape, and surface texture. Isolates with the highest percentages of germination, conidial yield, and radial growth were selected, and their pathogenicity was evaluated on second instar larvae of Galleria melonella under laboratory conditions. Results: In this study, Beauveria bassiana showed white colony color and aseptate hyphae, whereas Metarhizium robertsii showed dark green to light green colony color and septate hyphal structures. Maximum spore production and conidial length were obtained by Beauveria bassiana isolate APPRC-27 with 2.67x107 spores ml-1 and 3.24 µm, respectively. Colony radial growth rates ranged from 1.73 to 3.24 mm day-1. The results revealed that the highest mortality rate of Galleria melonella (100%) was obtained by Metarhizium robertsii isolates K-61 and K-102 at a concentration of 1x108 conidial ml-1 at 7 days post-inoculation. The lowest mortality rate was registered by Metarhizium robertsii isolate RST-11. Conclusions: In the present study, isolates that produced the most spores and had the highest germination rates were the most virulent to Galleria mellonella second instar larvae. Therefore, virulent entomopathogenic fungi, Beauveria bassiana and Metarhizium robertsii, are promising bioagents for the control of pests.

Fluid-based microbial processes modeling in Trichodesmium colony formation

In tropical and subtropical ocean gyres, Trichodesmium colonies account for up to half of the total N2 fixation in the ocean, making it one of the most ecologically significant N2-fixing cyanobacteria. The processes whereby Trichodesmium colonies and large-scale surface blooms form have not been investigated thoroughly. In particular, the effects of fluid motion have not been included in previous studies. As the first step toward understanding the mechanical processes associated with Trichodesmium colony synthesis, we propose a shear-related flow-based growth model to enlighten how fluid dynamics affect bacteria colony formation and growth. To investigate the possibility that early growth characteristics are strongly dependent on the shear rate, a two-way coupled fluid-colony interaction is developed using the lattice Boltzmann method for a porous colony. This model captures the exponential growth trend during the colony formation phase found in experiments. Our results show that the flow field significantly impacts both the colony growth rate and shape. In pure shear conditions, colonies grow in circular shapes, whereas in uniform flow, they take filament-like forms. Additionally, the Reynolds number (Re) plays a crucial role in shaping the colonies, especially in uniform flow conditions where its effect is more profound.

Antibacterial Activity of Ethanol Extract of Purple Kencana Leaves (Ruellia tuberosa L.) Using TLC-Bioautography and Agar Diffusion Methods

Tunjuk Langit Plant (Helminthostachys zeylanica (L.) Hook) contains a lot of secondary metabolite compounds, one of which is found in the root which contain the flavonoids ugonin and quercetin. The purpose of this study was to determine the antibacterial activity of compound 4 isolates IFATL-05 endophytic fungi from Tunjuk Langit (Helminthostachys zeylanica (L.) Hook) root against bacterial gastrointestinal tract infection. The results of purification of endophytic fungi with IFATL-05 code on macroscopic examination showed blackish-white fungus color, round with scalloped colony shapes, wavy edges and drop-like elevation angles. The process of separating the compounds using KLTP with n-hexane:ethyl acetate (1:1) as an eluent resulted in four bands of active compounds in UV lamps of 254 and 366 nm (TL-1, TL-2, TL-3 and TL-4). Test results for compound 4 isolates of IFATL-05 endophytic fungi from Tunjuk Langit root (Helminthostachys zeylanica (L.) Hook) using the Bioautographic TLC method using n-hexane:ethyl acetate (6:1) as eluent on Escherichia coli, Salmonella thypi, Shigella dysenteriae and Vibrio cholerae with Rf value = 0.90.

Ethnic empowering policies and postcolonial political exclusion in the British empire: An analysis of ethnic police recruitment and communal legislative representation

AbstractDoes ethnic empowerment under colonial rule shape ethnic power even after independence? Existing research offers mixed arguments and rarely differentiates between different types of political empowerment. Drawing on the historical observation that the parliament and the security forces were two of the major sources of political power in newly independent states, this preregistered study tests whether ethnic representation in the colonial constabulary force and the receipt of guaranteed communal representation in the colonial legislature reduces the risk of postcolonial ethnic exclusion in ex‐British colonies. It is found that the former has a strong and consistent effect on reducing the odds of postcolonial ethnic exclusion, but the latter, despite its frequent usage as a form of colonial ethnic empowerment, does not prevent political exclusion. The importance of martial vis‐à‐vis rational‐legal power in newly independent states and varying levels of diachronic continuity between the two forms of colonial empowerment may account for the diverging results.

Characterization of chitinolytic bacteria isolated from Ipomea pes caprae

Chitin has substantial benefits in several sectors including agriculture. In the plant protection field, chitin can promote the growth of certain bacteria which has possibly controlled the spread of fungal pathogens. Thus, chitinolytic bacteria producing chitinase enzymes can inhibit the growth of fungi. The purpose of this study was to examine the morphological and physiological characteristics of chitinolytic bacteria which collected from Ipomea pes caprae in Makassar and its ability to produce chitinolytic enzymes on medial culture. The method started to grow the isolates on the nutrient agar which were added to colloidal chitin. Furthermore, the bacteria were identified by its color, form, elevation and edge as well as tested its physiological characteristics with KOH 3% test and catalase test. In addition, bacterial chitinolytic index was carried out by using the disc diffusion method. The results showed that each isolate had yellowish white and grayish white colors; morphological characters: round and irregular colony shapes, colony edges smooth and choppy as well as umbonature and convex elevations. The physiological test results indicate that all isolates had a positive response in the catalase test, one of the isolates reacted positively to the gram test and the others reacted negatively to the test. Each isolate had chitinolytic activity with indices of 0.10, 0.09, 0.70, and 0.11.

First Report of Colletotrichum truncatum Causing Anthracnose in Tobacco in China.

In July 2022, large spots were observed on the leaves of tobacco in Guangxi province, China, whose shape was round and elliptical or irregular. The margins of spots were brown or dark brown with a pale yellow centre and several small black fruiting bodies. The pathogen was isolated by tissue isolation. Diseased leaves collected were cut into small pieces, sterilized with 75% ethanol for 30s and 2% sodium hypochlorite (NaCIO) for 60s, and rinsed with sterile deionized water for three times. Each air-dried tissue segment was cultured on potato dextrose agar (PDA) and incubated at 28℃ for 5 to 7 days in the dark (Wang et al. 2022). A total of six isolates were isolated, with differences in colony shape, edge type and colony colour, and aerial mycelium morphology, with the colony shape round or subrounded, and the edge rounded crenate, dentate or sinuate. The color of the colony was initially light yellow, then gradually changed to yellow and dark yellow. After 3-4 days, white aerial mycelia gradually grew up, which was peony-like or covered the whole colony, thus the color of the colony appeared white, and then gradually changed to orange, gray or nearly black, and all six isolates rarely produced conidia, which was consistent with the description of previous reports(Mayonjo and Kapooria 2003, Feng et al. 2021, Xiao et al. 2018). Conidia were hyaline, aseptate, and falcate, with the size of 7.8 to 12.9 × 2.2 to 3.5 μm. For molecular identification, the colony PCR method was used to amplify the internal transcribed spacer(ITS), actin(ACT), chitin synthase(CHS), and beta-tubulin(TUB2) loci of the six isolates using primer pairs ITS1/ITS4, ACT-512F/ACT-783R, CHS-79F/CHS-354R, and T1/Bt2b, respectively(Cheng et al. 2014). Partial sequences were amplified, sequenced, and uploaded to GenBank (GenBank accession Nos. OP484886，OP518265，OP518266，OP756065，OP756066, and OP756067 for ITS, OP620430 to OP620435 for ACT, OP620436 to OP620441 for CHS, and OP603924 to OP603929 for TUB2). These sequences had 99 to 100% similarity with C. truncatum isolates C-118(ITS), TM19(ACT), OCC69(CHS), and CBS 120709(TUB2) in GenBank. Homology matching was performed using BLAST and a phylogenetic tree was constructed using the Neighbor-Joining (NJ) method using MEGA (7.0) software based on ITS, ACT, CHS, and TUB2 sequences, which showed that all six isolates clustered in the same score as the C. truncatum. A pathogenicity test was performed with healthy tobacco infected with mycelial plugs (about 5 mm in diameter) of six isolates of C. truncatum from a 5-day-old culture, while negative controls on the other leaves were inoculated with sterile PDA plugs. All plants were placed in a greenhouse at 25℃ to 30℃ with 90% relative humidity. The experiment was conducted three times. Five days later, all inoculated leaves had diseased spots, whereas no symptoms appeared on negative controls. The same pathogen, C. truncatum, was identified from the inoculated leaves on the basis of morphological and molecular charchseristics as described above, fulfilling Koch's postulates. In this study, it is the first time to report that the anthracnose on tobacco was caused by C. truncatum. Thus, this work provides a foundation for controlling tobacco anthracnose in the future.

Storytelling, precarity and decolonizing practices

ABSTRACT In this article, we explore the decolonial feminist's contribution to the study of precarity and explain the role of storytelling in legitimizing the knowledge of ‘the other’ in the activism/critique of decolonial feminism. The article offers a critique of the recent conceptualization of precarity that tends to ignore the history of racialized and feminized bodies, and charts decolonial feminists’ conception of storytelling, in particular through Anzaldúa's, Mohanty's and Motta's work, as a way to gain political standing and offer possibilities to deal with precarity. By revealing the colonial and racial intersections shaping universal pretensions of precarity and how storytelling is a form of resistance and healing practice, this article contributes to bringing the South's own gaze to the actions the precarious might need today: that of transformative ethics recognizing differences rather than a universal individual and expressing the relationality of time and people in communities.

Isolation and identification of gastric acid-tolerant yeast from tapai

Lactobacilli and Bifidobacteria are the most extensively employed bacterial strains in marketable probiotic supplements. However, another probiotic was recently developed from yeast screening based on tolerance against gastric acid. This research aimed to isolate yeasts from traditional Indonesian fermented food (tapai). Screening of probiotic yeasts was based on their survival in gastric acid of pH 2.0. Yeast strains were cultured in malt extract agar, and their phenotype and genotype characteristics were identified. Phenotype characteristics were based on yeast cells’ colony, microscopy, and physiology. Meanwhile, genotype characteristics were determined using the PCR-fingerprinting technique to identify the sequence homology compared to the GenBank database and the phylogenetic tree construction. The result showed that SUL and SM isolates have the highest survival on artificial gastric acid of pH 2.0. The SUL isolate from tapai brand “Sumber Madu” has a morphologically wrinkled colony, no pseudo mycelium, white surface colony, and round cell shape. In contrast, the SM isolate from tapai brand “Sari Madu” has a thin wide colony with no pseudo mycelium, turbid white surface, and oval cell shape. After 2 h incubation on gastric acid, SUL and SM isolates grew up to 6.20±0.35 CFU/mL (survival yeast of 82.71%) and 5.75±0.45 CFU/mL (survival yeast of 79.74%), respectively. The SUL isolate was identified as Kodamaea ohmeri, while the SM isolate was identified as Pichia kudriavzevii.

Isolation, morphological characterization, and screening virulence of Beauveria bassiana and Metarhizium robertsii fungal isolates on Galleria mellonella.

Entomopathogenic fungi exists naturally in plants as an asymptote and have the potential to reduce the population of insect pests through indirect interactions. This study was conducted to detect and characterize the endophytic fungi Beauveria bassiana and Metarhizium robertsii from the rhizosphere soil of tomato plants and their virulence effect on Galleria melonella. From the rhizosphere soil of 40 tomato fields, three Beauveria bassiana and seven Metarhizium robertsii isolates were isolated using the galleria bait method. All fungi isolate were morphologically characterized by their colony color, shape, and surface texture. Isolates with the highest percentages of germination, conidial yield, and radial growth were selected, and their virulence was evaluated on second instar larvae of Galleria melonella under laboratory conditions. In this study, Beauveria bassiana showed white colony color and aseptate hyphae, whereas Metarhizium robertsii showed dark green to light green colony color and septate hyphal structures. Maximum spore production and conidial length were obtained by Beauveria bassiana isolate APPRC-27 with 2.67x10 7 spores ml -1 and 3.24 µm, respectively. Colony radial growth rates ranged from 1.73 to 3.24 mm day -1. The results revealed that the highest mortality rate of Galleria melonella (100%) was obtained by Metarhizium robertsii isolates K-61 and K-102 at a concentration of 1x10 8 conidial ml -1 at 7 days post-inoculation. The lowest mortality rate was registered by Metarhizium robertsii isolate RST-11. In the present study, isolates that produced the most spores and had the highest germination rates were the most virulent to Galleria mellonella second instar larvae. Therefore, virulent entomopathogenic fungi, Beauveria bassiana and Metarhizium robertsii, are promising bioagents for the control of insect pests.

Establishment of a 3D Model to Characterize the Radioresponse of Patient-Derived Glioblastoma Cells.

Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor in adults. Despite modern, multimodal therapeutic options of surgery, chemotherapy, tumor-treating fields (TTF), and radiotherapy, the 5-year survival is below 10%. In order to develop new therapies, better preclinical models are needed that mimic the complexity of a tumor. In this work, we established a novel three-dimensional (3D) model for patient-derived GBM cell lines. To analyze the volume and growth pattern of primary GBM cells in 3D culture, a CoSeedisTM culture system was used, and radiation sensitivity in comparison to conventional 2D colony formation assay (CFA) was analyzed. Both culture systems revealed a dose-dependent reduction in survival, but the high variance in colony size and shape prevented reliable evaluation of the 2D cultures. In contrast, the size of 3D spheroids could be measured accurately. Immunostaining of spheroids grown in the 3D culture system showed an increase in the DNA double-strand-break marker γH2AX one hour after irradiation. After 24 h, a decrease in DNA damage was observed, indicating active repair mechanisms. In summary, this new translational 3D model may better reflect the tumor complexity and be useful for analyzing the growth, radiosensitivity, and DNA repair of patient-derived GBM cells.

The Combating Impact of Biogenic Silver Nano Particles and Antibiotics on Combating Multidrug-Resistant Pseudomonas

This study aimed to assess the synergistic effect of silver nanoparticles (AgNPs) in combination with different antibiotics against multidrug-resistant Pseudomonas aeruginosa (MDR P. aeruginosa) infections. A total of 120 surgical or burn wound samples were collected from a tertiary care hospital. The samples were cultured on cetrimide agar plates and then heated to 370 degrees Celsius. The isolates were identified based on colony shape, Gram's staining, and various biochemical tests. The antibiotic susceptibility profile was determined using the Kirby-Bauer disc diffusion technique according to CLSI 2022 recommendations. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were also determined. The antibacterial activity of AgNPs was evaluated using the agar well diffusion technique and the microdilution method. The synergistic effect of antibiotics and AgNPs was assessed using the Checkerboard method. Out of the 120 samples, 46 (38.8%) were confirmed as positive for P. aeruginosa, and among them, 33 were identified as MDR P. aeruginosa. Seven representative isolates were selected for further analysis. The antibacterial activity of AgNPs showed a maximum zone of inhibition of 12mm at 4mg/ml and a minimum of 2.5mm at 1mg/ml using the agar well diffusion method. The MIC and MBC of AgNPs indicated that all isolates were inhibited at a concentration of 250mg/ml. The Checkerboard results revealed that colistin and gentamicin exhibited complete synergism with AgNPs, while ciprofloxacin showed partial synergism with AgNPs.

Isolation, morphological characterization, and screening a virulence of Beauveria bassiana and Metarhizium robertsii as bioagents

Background: Entomopathogenic fungi exists naturally in plants as an asymptote and has the potential to reduce the population of insect pests through indirect interactions. This study was conducted to detect and characterize the endophytic fungi Beauveria bassiana and Metarhizium robertsii from the rhizosphere soil of tomato plants and their virulence effect on Galleria melonella. Methods: From the rhizosphere soil of 40 tomato fields, three Beauveria bassiana and seven Metarhizium robertsii isolates were identified using the galleria bait method. All fungi isolates were morphologically characterized by their colony color, shape, and surface texture. Isolates with the highest percentages of germination, conidial yield, and radial growth were selected, and their pathogenicity was evaluated on second instar larvae of Galleria melonella under laboratory conditions. Results: In this study, Beauveria bassiana showed white colony color and aseptate hyphae, whereas Metarhizium robertsii showed dark green to light green colony color and septate hyphal structures. Maximum spore production and conidial length were obtained by Beauveria bassiana isolate APPRC-27 with 2.67x107 spores ml-1 and 3.24 µm, respectively. Colony radial growth rates ranged from 1.73 to 3.24 mm day-1. The results revealed that the highest mortality rate of Galleria melonella (100%) was obtained by Metarhizium robertsii isolates K-61 and K-102 at a concentration of 1x108 conidial ml-1 at 7 days post-inoculation. The lowest mortality rate was registered by Metarhizium robertsii isolate RST-11. Conclusions: In the present study, isolates that produced the most spores and had the highest germination rates were the most virulent to Galleria mellonella second instar larvae. Therefore, virulent entomopathogenic fungi, Beauveria bassiana and Metarhizium robertsii, are promising bioagents for the control of pests.

Haitian Mawonaj, the “Picaroons,” and Re-centering the Maritime Dimensions of Maroon History

The memory and language of colonial marronage shape the zeitgeist and the wider history of Haiti as nation. This essay takes as its point of departure the recent use of small boats by armed gangs in Haiti to revisit the shipboard dimensions of marronage and the country’s history of “picaroon” warfare. Attempting to consider the condition of instability and ungovernability and the current crises of Haiti in light of Maroon histories poses the question of whether the concept of “social banditry” has any value when generalized banditry comes to permeate an entire country amid the widespread breakdown of society itself.

Pyocyanin is the Microbial Blue-green Pigment: A Review on its History, Virulence, and Therapeutic Use

Background: P. aeruginosa, has been frequently connected to immune-compromised individuals. Dynamic electrochemical metabolite assists in the creation of biofilms, the production of genes, and the maintenance of bacterial cells. The bacteria produce several phenazine derivatives, as well as the blue-green pigment pyocyanin, which works as a signalling molecule in quorum signalling and virulence factors. Objective: This review paper intends to give information on the compound's history, virulence mechanism, current biological horizon opened, as well as antagonism and bio-control actions in other bacteria. Current industrial trends and the prospects of pyocyanin-based development were also analysed. Methods: A bibliographic search of scientific literature published up to 2020 was conducted using scientific databases and search engines. Pyocyanin, phenazine, Pseudomonas, virulence, quorum signalling, health, in vivo, and clinical investigations were among the keywords used in various combinations. The data were retrieved independently from eligible papers using the usual data extraction approach. Results: Due to pyocyanin's antibacterial properties, the pharmaceutical industry is predicted to grow faster than other businesses. P. aeruginosa which has had its respiratory chain altered by protonated 3,5-dichlorophenol in water can be used as a biosensor. Cellular systems exposed to the chemical experience increased oxidative stress, which leads to gradual apoptosis. Pyocyanin is engaged in bacterial signalling processes, influencing colony shape and alarming innate immune cells. Conclusion: Focused research on the virulence factor is required, as the specific contribution remains unknown. The link between biological and therapeutic features needed well description to determine the precise action mechanism(s) to design novel medications.

Isolation and identification of microorganisms from bitumen, and soil around bitumen deposit site

Isolation of microorganisms from hydrocarbon and oil polluted environment has been reported over the years. This study focused on the isolation and identification of microorganisms from bitumen, and soil around bitumen deposit site. Microorganisms were isolated from soil sample collected around bitumen deposit and bitumen itself using pour plate method. The cultural and morphological characteristics of each bacteria isolates such as colony shape, elevation, pigmentation, colour, cell shape, gram reaction, motility, and endospore test were carried out. From the result, the following bacteria were identified; Acinetobacter sp (soil and bitumen), Pseudomonas Aeruginosa (soil), Bacillus subtilis (soil and bitumen), Staphylococcus aureus (soil). Mould isolation was carried out by cutting a small portion of mycelium, stained it with cotton blue in lactophenol and the examined carefully under light microscope with x40 0bjective. The result revealed the following mould isolates; Aspergillus niger and Arthrobotrys oligospora both isolated from the soil. The result showed the isolation of microorganisms from bitumen and soil around bitumen deposit, thus their potential usefulness in remediation of bitumen polluted environment if the exploitation of the resource commenced.

Identification and count of bacteria on the palms of fried food sellers

The palm is the part of the body that is most often used daily to carry out various activities, which makes hands very easily contaminated by bacteria. This causes the palm of the hand can act as a medium for transmission of various types of diseases. This study aims to identify and count the number of bacteria on the palms of fried food sellers. This research technique was carried out by laboratory observation with the object of research being the palms of 10 fried food sellers in Rappocini District, Makassar City. Based on the results of research that has been carried out from 10 samples, it has been identified microscopically the form of gram-negative bacilli is red and clustered and macroscopic identification shows the shape of bacterial colonies is round, jagged with small to large sizes, while the results of calculating the number of bacteria for all samples obtained the number of bacteria in large numbers (TBUD). It can be concluded that the palms of fried food sellers in Rappocini District, Makassar City are positive for gram-negative bacilli with an amount that cannot be counted (TBUD).

Influence of Different Temperature Regimes and Culture Media on the Growth and Sporulation of Alternaria brassicae Causing Alternaria Blight of Mustard

Mustard (Brassica juncea L.) is the second most important oilseed commodity in India. Alternaria blight (Alternaria brassicae) is one of the devastating fungal pathogen, resulting in severe yield losses to the crop. The present study is conducted in-vitro to know the effect of different temperature regimes and various culture media on the mycelial growth and sporulation of A. brassicae. It is clearly evident from the results that all the tested temperature regimes and culture media showed variation in the colony diameter and other cultural characteristics. The temperature of 25°C significantly encouraged mycelial growth (85.00 mm) and exhibited excellent sporulation of A. brassicae compared to 15 and 35°C. In case of culture media, Potato Dextrose Agar was found to be significantly superior over the other media and registered maximum mycelial growth (82.00 mm) with excellent sporulation. However, Oat Meal Agar supported the minimum mycelial growth (45.00 mm) with fair sporulation. The variation in cultural characteristics (colony color, growth, appearance, and shape etc.) was also observed with various culture media.