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The workshop on the application of Biology online (on a network) using the internet during the Covid-19 pandemic has been held at SMA Plus Al Wahid, Tasikmalaya Regency. This activity is in the context of a community service program entitled IPB lecturers to serve. The objectives of this activity are: 1) To describe the implementation of an online explanation workshop program for high school level Biology learning, especially those related to viruses and body immunity; 2) Explaining the level of understanding of the workshop participants before and after the presentation of the material; and 3) Explaining the results of the evaluation of participants' satisfaction with the delivery of workshop materials. The workshop was held on September 4, 2020 online using the Zoom application platform. The number of participants who took part in the workshop was 43 people, consisting of students in grades X, XI, and XII in the natural sciences, teachers, and the general public (non-teacher high school employees) from SMA Plus Al Wahid. Only 16 student participants who filled out the pre-test and post-test were used to evaluate this activity. Evaluation of the results of the pre-test and post-test using a one-group pre-test-post-test design using the N gain method or normalized gain analysis. The results of the workshop showed an increase in participants' understanding of the material on the application of Biology by 30.6% and participants showed a satisfaction level of 76.25%.

Sheilahrusi, Priyanto JA, Rismiyati H, Rusmana I, Budiarti S. 2021. Short Communication: The potency of lytic bacteriophage isolated from various environments to control the growth of Citrobacter braakii causing urinary tract infection. Biodiversitas 22: 5550-5554. Citrobacter braakii is one of the pathogenic bacteria causing urinary tract infection (UTI) in humans. Bacteriophages that are specifically infecting C. braakii could be the alternatives to combat antibiotics resistance cases of this bacterium. This study aimed to isolate lytic phages from various environmental samples (tofu factory wastewater, sewage water, rice field water, fishpond water, cattle farm wastewater, and goat farm wastewater), and to analyze their effectivity to reduce UTI-causing C. braakii population in vitro. Results exhibited that phages targeting this bacterium were found in goat and cattle farm wastewater and not present in other samples. Two phages, namely FC1 and FC2, had different plaque morphology characteristics. The number of phages in cattle farm wastewater was 2.8 × 105 PFU/mL and 1.32 × 104 PFU/mL in goat farm wastewater. It was observed that the phages found in these environments also indicate the presence of their host. After 8 h incubation, FC1 and FC2 phage reduced UTI-causing C. braaakii population in vitro from 0.23×108 CFU/mL to 0.03×108 CFU/mL and 0.02×108 CFU/mL, respectively. The phages isolated from these two samples can be further developed for the treatment of UTI caused by C. braakii and goat and cattle farm wastewater treatment to prevent contaminating other areas.

Wahyudi AT, Fitriansyah NG, Amri MF, Priyanto JA, Nawangsih AA. 2021. Screening of chitinase-producing rhizosphere actinomycetes and their genetic diversity. Biodiversitas 22: 4186-4192. Soil microbial community, especially rhizosphere actinomycetes, plays an important role in protecting plants from phytopathogenic fungi by producing various agroactive compounds, including mycolytic enzymes particularly chitinase. The objective of this study was to investigate chitinase activity and analyze the diversity of family 19 chitinase genes of actinomycetes isolated from maize and soybean rhizosphere. Of fivety actinimycetes, Seventeen isolates exhibited chitinolytic activities and formed a hydrolytic zone around the colony with chitinolytic index ranging from 0.49±0.01 to 2.15±0.69, qualitatively tested in 0.3% chitin agar medium. Six selected isolates (ARJ 36, ARJ 81, ARJ 15, ARK 17, ARK 143, ARK 103) showed chitinase activities ranging from 0.157±0.04 to 0.440±0.09 U/mL, based on chitinolytic index. The production of chitinase was confirmed by the presence of family 19 chitinase encoding genes from Streptomyces sp. Some conserved regions and essential amino acid residues were also detected. This study suggests that chitinolytic actinomycetes isolated from maize and soybean rhizosphere can be studied further as biological control candidates for controlling phytopathogenic fungi.

Objective: This study was aimed to isolate and screen marine sponge-associated bacteria producing anti-Vibrio compounds and to identify their compounds from the bacterial extract. Methods: Sponge-associated bacteria were isolated by spread plate method. Their anti-Vibrio activity against Vibrio parahaemolyticus, V. harveyi, and V. vulnificus was determined by dual culture test. Three potential isolates were identified based on 16S-rRNA gene analysis. All isolates producing anti-Vibrio compounds was tested for their haemolytic characters in blood agar medium. Anti-Vibrio activity of the most potential isolate was also tested by using its supernatant, extract, and concentrated culture. Chemical composition of crude extract derived from that isolate was identified by GC-MS analysis. Results: 68 bacterial isolates have been isolated from the marine sponge, Spongia sp., Svenzea sp., Ircinia sp., and Igernella sp. Of 68 isolates, 15 (22%) isolates had anti-Vibrio activities in various spectra against three Vibrio species, including V. harveyi, V. parahaemolyticus, and V. vulnificus. All isolates producing anti-Vibrio compounds were non-haemolytic. Bacterial isolates coded as D6.6, D6.19, and P4.17 have broad spectra. They could inhibit at least two Vibrio species as indicated by the clear zone formed around bacterial colonies. Based on 16S-rRNA, these isolates were closely related (similarity ≥ 99%) to Brevibacterium casei strain M Sw oHS, Bacillus altitudinis strain FJAT 47750, and Bacillus altitudinis strain PgBe190, respectively. D6.6 isolate was the most potential isolate, which could inhibit three Vibrio species. Consistently, its anti-Vibrio activity also confirmed by their supernatant, concentrated culture, and crude extract of that isolate. The crude extract derived from this isolate contained 10 major compounds that are biologically active. Conclusion: This study suggests that 15 bacteria strains isolated from marine sponges were potentially could inhibit Vibrio’s growth in vitro. These isolate could be further explored as anti-Vibrio agent.

Inggraini M, Nurfajriah S, Priyanto JA, Ilsan NA. 2021. Antimicrobial susceptibility and molecular species identification of clinical carbapenem-resistant bacteria. Biodiversitas 22: 555-562. Antibiotic is the first option treatment for infectious diseases both in human and animal. However, the excessive usage and misuse of antibiotics have driven antibacterial resistances worldwide and the increasing case of antibiotic resistance leads to limited options for treatment. This study aimed to observe antimicrobial susceptibility and molecular identification of carbapenem-resistant human clinical bacteria. A total of nine isolates in this study were collected in 2020 from a teaching hospital in Indonesia. All isolates were originated from various human clinical specimens, including urine, blood, pus, and sputum. Identification using 16s rRNA-based showed that these isolates were closely related to Klebsiella pneumoniae (1/9), A. baumannii (5/9), Escherichia coli (2/9), and Lysinibacillus fusiformis (1/9). According to minimum inhibitory concentration using Vitek Automated Machine, four isolates of multi-drug resistant (MDR) bacteria were found. In contrast, five of them were categorized as extensively-drug resistant (XDR). Interestingly, all of the XDR isolates belonged to A. baumannii. These isolates were resistant to at least seven different antimicrobial classes. A comparison of partial 16s rRNA showed two E. coli had similar variance. While in A. baumannii isolates, we found one of five isolates had a different variance sequence, which suggests different clonality among this species. This study gives an insight into the prevalence of carbapenem-resistant bacteria with XDR criteria in Indonesia.

Plant Growth Promoting Rhizobacteria (PGPR) is considered as the biological agent for improving plant growth. One Group of PGPR that have an important role in growth promoting of plant is Actinomycetes. The objective of this study was to isolate and screen Actinomycetes isolated from soybean rhizosphere as growth promoter of soybean in vitro. Fifty-three Actinomycetes isolates have successfully been isolated from soybean rhizosphere using two media, mainly Humic acid Vitamin Agar (HVA) and starch casein agar (SCA). Among 53 isolates, 18 (34%) isolates were able to produce IAA in range of 2.08 ppm to 16.70 ppm. Growth promotion test of soybean in vitro using Ragdoll method resulted 7 Actinomycetes isolates that significantly enhanced 3 plant growth parameters, including hypocotyl and radicular length as well as the number of lateral roots. Of those 7 isolates of Actinomycetes, 5 isolates were able to grow on nitrogen-free medium and solubilize phosphate. Those 5 isolates also were found as non-pathogenic, based on the negative reaction in hypersensitivity test. Based on 16S rRNA sequence analysis, 5 selected Actinomycetes isolates were highly homolog with Streptomyces genera in different taxa of species and strains (similarity ≥99%). Our finding reveals a potent application of 5 Actinomycetes isolates as plant growth promoter in soybean agriculture.

Sponge associated bacteria with diverse NRPS-PKS genes could be the alternative source of bioactive compounds. This study aimed to analyze the activity as well as the regulatory mechanism regarding the anticancer properties derived from these bacteria against cancer cell lines. Extraction of bacterial metabolites using ethyl acetate solvent resulted yield ranging from 0.003 to 0.016% (w/v). Six extracts of bacterial metabolites showed markedly cytotoxic activity against 8 human hematopoietic cancer cell lines, with IC50 value 27.24 to 533.73 μg mL-1 in a dose dependent response, as assessed by MTT test. Supporting those results, reduction of cell density, morphological changes including cell shrinkage and formation of the apoptotic body of cancer cells lines, were found. As it might be due to the inhibitory effect of bacterial extract treatment. Apoptosis assay determined by annexin V-FITC apoptosis analysis showed that apoptotic cells were induced by bacterial extract after 6 h of treatment. Thus suggesting that the extract could be one of the external signals that activate the signal transduction pathway of apoptosis, especially in MOLT4 cells, acute lymphoblastic leukemic cell lines. Cell cycle analysis using propidium iodide revealed that the extract HAA 01 caused cell cycle arrest, since most of the MOLT4 cells were accumulated in Sub-G1 phase after 24 h of extract treatment. Interestingly, glycerol, lactose and amylum were the more preferable carbon source to produce anticancer compounds, than glucose. Our study indicates that anticancer activity of HAA 01 (identified as Bacillus subtilis based on API identification) extract is highly correlated with NRPS-PKS gene expression which is likely regulated by the type of carbon source.

Wahyudi AT, Priyanto JA, Fijrina HN, Mariastuti HD, Nawangsih AA. 2019. Streptomyces spp. from rhizosphere soil of maize with potential as plant growth promoter. Biodiversitas 20: 2547-2553. Actinomycete is one group of rhizobacteria that plays an important role as a plant growth promoter. This study was aimed to evaluate the potential of Actinomycetes isolated from maize rhizosphere in promoting plant growth in vitro including their ability to produce IAA, promote maize sprout growth, solubilize phosphate, and grow in N-free medium. Thirty isolates have been isolated from maize rhizosphere using a spread plate method. All 30 isolates were probably not pathogenic to plants as tested by hypersensitivity reaction test on tobacco leaves. Based on the colorimetric assay, 30 isolates (100%) were able to produce IAA with concentrations ranging from 1.05 to 26.89 ppm. The highest concentration of IAA (26.89 ppm) produced by ARJ 21 and the lowest IAA concentration (1.05 ppm) produced by ARJ 12. By using the Ragdoll method, it showed that 9 isolates (30%) were able to promote maize sprout growth significantly on five growth parameters including primary root length, stem length, number of lateral roots, wet weight and dry weight. Twenty-one isolates (70%) were capable of solubilizing phosphate in Pikovskaya medium containing tricalcium phosphate. Also, 30 isolates (100%) were able to grow on N-free medium, suggesting their ability to fix nitrogen. Based on 16S-rRNA, five potential isolates with plant growth-promoting properties were highly similar to Streptomyces spp. Based on their potential characters, these Actinomycetes isolates have the potential to be further developed as a biofertilizer agent for sustainable maize farming.