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Tannins are capable of producing natural dyes with antioxidant and antibacterial propertis, while synthetic dyes are commonly used in the textile industry, causing environmental issues like water pollution. This research aims to utilize waste tannins as natural dyes as an alternative to synthetic dyes. This study examined the effect of the extraction method on tannin properties such as phenolic content, antioxidants, and antibacterial activity. In addition, Pyrolysis Gas Chromatography‒Mass Spectrometry (Py-GCMS) analysis was used to identify the effect of extraction temperature on the chemical elucidation of tannin. The effect of tannin concentration was evaluated against four bacteria that are usually found on human skin: Staphylococcus epidermidis, Bacillus subtilis, Propionibacterium acnes, and Staphylococcus aureus. Extraction temperature significantly influences the chemical composition of tannin, which leads to different antioxidant properties. The maximum antibacterial properties of tannin were obtained at 90°C with the inhibition zone in the range of 0.9–1.0 mm against four bacteria, tannin yield of 26.59%, Gallic Acid Equivalents or total phenolic content (GAE) of 40.30 mg/g, and Radical Scavenging Activity or antioxidant activity (RSA) of 89.88%. Moreover, the concentration of tannin was significantly linear with its antibacterial properties. Tannin was successfully applied to the textile by using alum as a mordanting agent to create an antibacterial textile. The textile's bacterial structure damage was analyzed under Field Emission Scanning Electron Microscopy (FESEM). After 50 washings, tannin-textiles with alum-modified properties remained stable compared to those without alum, with S. aureus and S. epidermidis being the most vulnerable bacteria, as confirmed by FESEM images. Hence, tannin is a feasible alternative to harmful and nondegradable synthetic dyes and antibacterial agents. [ABSTRACT FROM AUTHOR]

The antibacterial agent can be extracted from plants, animals, and microorganisms such as fungi. The potential antibacterial activity of laccase derived from fungi remains limited in current reports. This study aimed to investigate the characteristics of laccase from Indonesian white rot fungi (WRF) and explore its potential as an antibacterial agent. The laccases were produced by Trametes hirsuta D7, Trametes hirsuta EDN 082, Leiotrametes menziesii BRB 73, and Lentinus sajor-caju BRB 12 using oil palm empty fruit bunch as a substrate. The results showed that the Indonesian WRF tested produced brownish-yellow laccase. FTIR analysis demonstrated similar peak patterns but distinct absorption intensities among the laccases. Trametes hirsuta D7 gained 0.044 U/ml of the greatest laccase activity. Laccase, with minimal activity of 0.001 U/ml–0.026 U/ml, suppressed the propagation of Propionibacterium acnes and Staphylococcus aureus. Escherichia coli and Pseudomonas aeruginosa could be inhibited by the laccase with a minimum activity of 0.002 U/ml–0.044 U/ml. However, S. aureus and E. coli showed the Minimum Bactericidal Concentration in the laccase activity range of 0.018 U/ml–0.308 U/ml. Gram-positive and Gramnegative bacteria grow more slowly when the laccase is present, supposed the laccase as a potential antibacterial agent. [ABSTRACT FROM AUTHOR]

Chemical pesticide has been used extensively to control Spodoptera litura that attack economically important crops.The use of synthetic pesticides with high intensity is detrimental to the quality of life. The objective of this study was to evaluate the insecticidal activity of entomopathogenic fungi and neem-based biopesticide on S. litura using spraying and forced feeding method. The treatments were spore solution of Trichoderma viride, Metarhizium sp. T4.B23, Metarhizium sp. B2.2 applied at 108 spores/mL, biopesticide formulation containing neem extract (Agr1) at 10% (v/v), and water as control. Each treatment was sprayed 0.3 mL directly onto larvae of S. litura while in forced feeding method, the larvae were fed on 1 gr of treated water spinach. Entomopathogenic fungal spore solution did not show efficacy on S litura larvae in both methods, while Agr 1 caused 90 and 40% mortality in spraying and forced feeding method, respectively. Furthermore, the efficacy of Agr 1 was compared to Agr 2 that contains neem extract and wood vinegar. Agr 2 caused 100% mortality when sprayed onto S. litura larvae, and more than 90% of larvae were died when forced to feed treated water spinach. Agr2 has better potential than Agr1 to control S. litura.

Due to the climate change and global warming, the biodiversity database has gained the attention of the government. In line with the Indonesian Biodiversity Strategy and Action Plan (IBSAP), we have collected plants with insecticidal activity based on the local wisdom. This program aimed to protect Indonesian biodiversity from deforestation along with the loss of the number of species. This research's goal was to evaluate termiticidal and antifungal properties from some plant extracts collected from the Turgo forest area, Mt. Merapi National park, Java. Three potential plants were evaluated. Based on specimen identification, the three plant samples were Kina (Cinchona sp.), Kamadoh (Dendrocnide stimulans (L.f.) Chew), and Keremi (Homalanthus populneus (Geiseler) Pax). The phytochemical test showed that Kina contained alkoloid, falvonoid, saponin, and tannin, whereas Kamadoh and Keremi contained saponin and tanin, respectively. Overall, all plant extracts have the termiticidal activities and able to inhibit wood-decay fungi with the inhibition percentage around 60% - 100%. Leaf extracts of Kina (Cinchona sp) and Keremi (Homalanthus populneus (Geiseler) showed the highest activity as wood-decay fungi inhibitor. The disclosure of the potential of bioinsecticides from some plants originating from Mount Merapi is very important before being lost due to deforestation and the Mount Merapi disaster. Thus, the potential bioinsecticide in these plants can increase its economic value as a substitute for synthetic insecticides that are friendly to the environment. [ABSTRACT FROM AUTHOR]

Actinomycetes are Gram positive bacteria that have been detected in diverse ecological niches. Their member species are known to be a main source of various bioactive compounds. The discovery of Actinomycetes from diverse and unexplored resources has also been linked to increased opportunities to obtain novel bioactive compounds. Insect nest material is being investigated as a new source of novel antimicrobial producing Actinomycetes, which could be harnessed for therapeutic potential. A total of 10 Actinomycetes isolates were collected from the nest of Nasutitermes sp. in Pananjung Pangandaran Nature Reserve. These isolates were evaluated for antimicrobial activity against the challenge bacteria (Eschericia coli, Staphylococcus aureus, Bacillus subtilis, Serratia marcescens) and fungi (Fomitopsis palustris, Fusarium oxysporum, Trichoderma viridae) by dual culture method. The result revealed that several isolates were active against fungi and bacteria. Isolate Pn-TN2 showed the highest level of antibacterial inhibition and the highest antifungal inhibition with Inhibition Rate value more than 80%. By morphological and 16S rRNA gene sequence analysis strongly suggested that the isolate Pn-TN2 belonged to Streptomyces prasinopilosus. We suggested that termite nest is a potential source of bioactive strains of cultivable Actinomycetes for future biotechnological needs. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to develop antimicrobial bioplastics based on Poly Lactic Acid (PLA) with the addition of chitosan-ZnO, and chitosan-TiO2 to improve antimicrobial properties.For the preparation of the bioplastics, PLA with chitosan-ZnO or chitosan-TiO2 were used. The antimicrobial activity, mechanical and thermal properties, and water vapor permeability of bioplastics were evaluated.PLA-chitosan-ZnO indicated a robust antimicrobial activity against bacteria such as Salmonella typhi, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, yeast such as Candida albicans, and fungus Aspergillus niger. No formation of new functional groups in PLA-chitosan-ZnO composites. In comparison to other PLA-based bioplastics, this bioplastic has medium tensile strength, tensile modulus, and elongation percentages with low barrier ability to water vapor. Chitosan-ZnO itself has a greater tensile strength compared to chitosan-TiO2. These two compounds undergo 2 stages of decomposition in a temperature range of 43 °C to 265 °C. The addition of PLA into chitosan-ZnO or chitosan TiO2 causes the bioplastics decomposed in a single stage. It also increases the decomposition temperature of bioplastic. However, compared to chitosan-ZnO or TiO2, the PLA-chitosan-ZnO or TiO2 bioplastics tend to produce a fragile composite indicating by decrease in their tensile strength.In general, the addition of chitosan-ZnO into in PLA-based bioplastic produces better antimicrobial properties compared to TiO2.Methods: The purpose of this study was to develop antimicrobial bioplastics based on Poly Lactic Acid (PLA) with the addition of chitosan-ZnO, and chitosan-TiO2 to improve antimicrobial properties.For the preparation of the bioplastics, PLA with chitosan-ZnO or chitosan-TiO2 were used. The antimicrobial activity, mechanical and thermal properties, and water vapor permeability of bioplastics were evaluated.PLA-chitosan-ZnO indicated a robust antimicrobial activity against bacteria such as Salmonella typhi, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, yeast such as Candida albicans, and fungus Aspergillus niger. No formation of new functional groups in PLA-chitosan-ZnO composites. In comparison to other PLA-based bioplastics, this bioplastic has medium tensile strength, tensile modulus, and elongation percentages with low barrier ability to water vapor. Chitosan-ZnO itself has a greater tensile strength compared to chitosan-TiO2. These two compounds undergo 2 stages of decomposition in a temperature range of 43 °C to 265 °C. The addition of PLA into chitosan-ZnO or chitosan TiO2 causes the bioplastics decomposed in a single stage. It also increases the decomposition temperature of bioplastic. However, compared to chitosan-ZnO or TiO2, the PLA-chitosan-ZnO or TiO2 bioplastics tend to produce a fragile composite indicating by decrease in their tensile strength.In general, the addition of chitosan-ZnO into in PLA-based bioplastic produces better antimicrobial properties compared to TiO2.Results: The purpose of this study was to develop antimicrobial bioplastics based on Poly Lactic Acid (PLA) with the addition of chitosan-ZnO, and chitosan-TiO2 to improve antimicrobial properties.For the preparation of the bioplastics, PLA with chitosan-ZnO or chitosan-TiO2 were used. The antimicrobial activity, mechanical and thermal properties, and water vapor permeability of bioplastics were evaluated.PLA-chitosan-ZnO indicated a robust antimicrobial activity against bacteria such as Salmonella typhi, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, yeast such as Candida albicans, and fungus Aspergillus niger. No formation of new functional groups in PLA-chitosan-ZnO composites. In comparison to other PLA-based bioplastics, this bioplastic has medium tensile strength, tensile modulus, and elongation percentages with low barrier ability to water vapor. Chitosan-ZnO itself has a greater tensile strength compared to chitosan-TiO2. These two compounds undergo 2 stages of decomposition in a temperature range of 43 °C to 265 °C. The addition of PLA into chitosan-ZnO or chitosan TiO2 causes the bioplastics decomposed in a single stage. It also increases the decomposition temperature of bioplastic. However, compared to chitosan-ZnO or TiO2, the PLA-chitosan-ZnO or TiO2 bioplastics tend to produce a fragile composite indicating by decrease in their tensile strength.In general, the addition of chitosan-ZnO into in PLA-based bioplastic produces better antimicrobial properties compared to TiO2.Conclusion: The purpose of this study was to develop antimicrobial bioplastics based on Poly Lactic Acid (PLA) with the addition of chitosan-ZnO, and chitosan-TiO2 to improve antimicrobial properties.For the preparation of the bioplastics, PLA with chitosan-ZnO or chitosan-TiO2 were used. The antimicrobial activity, mechanical and thermal properties, and water vapor permeability of bioplastics were evaluated.PLA-chitosan-ZnO indicated a robust antimicrobial activity against bacteria such as Salmonella typhi, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, yeast such as Candida albicans, and fungus Aspergillus niger. No formation of new functional groups in PLA-chitosan-ZnO composites. In comparison to other PLA-based bioplastics, this bioplastic has medium tensile strength, tensile modulus, and elongation percentages with low barrier ability to water vapor. Chitosan-ZnO itself has a greater tensile strength compared to chitosan-TiO2. These two compounds undergo 2 stages of decomposition in a temperature range of 43 °C to 265 °C. The addition of PLA into chitosan-ZnO or chitosan TiO2 causes the bioplastics decomposed in a single stage. It also increases the decomposition temperature of bioplastic. However, compared to chitosan-ZnO or TiO2, the PLA-chitosan-ZnO or TiO2 bioplastics tend to produce a fragile composite indicating by decrease in their tensile strength.In general, the addition of chitosan-ZnO into in PLA-based bioplastic produces better antimicrobial properties compared to TiO2. [ABSTRACT FROM AUTHOR]