Xylanopectinolytic enzymes by marine actinomycetes from sediments of Sarena Kecil, North Sulawesi: high potential to produce galacturonic acid and xylooligosaccharides from raw biomass.

BACKGROUND: Actinomycetes isolated from marine habitats are known to have the potential for novel enzymes that are beneficial in the industry. In-depth knowledge is necessary given the variety of this bacterial group in Indonesia and the lack of published research. Actinomycetes isolates (BLH 5-14) obtained from marine sediments of Sarena Kecil, Bitung, North Sulawesi, Indonesia, showed an ability to produce pectinase and xylanase that have equal or even higher potential for pectic-oligosaccharides (POS) and xylooligosaccharides (XOS) production from raw biomass than from commercial substrates. This study's objective was to characterize both enzymes to learn more for future research and development. RESULTS: Pectinase had the highest activity on the 6th day (1.44±0.08 U/mL) at the optimum pH of 8.0 and optimum temperature of 50 °C. Xylanase had the maximum activity on the 6th day (4.33±0.03 U/mL) at optimum pH 6.0 and optimum temperature 60 °C. Hydrolysis and thin layer chromatography also showed that pectinase was able to produce monosaccharides such as galacturonic acid (P1), and xylanase was able to yield oligosaccharides such as xylotriose (X3), xylotetraose (X4), and xylopentaose (X5). BLH 5-14 identified as the genus Streptomyces based on the 16S rDNA sequences and the closely related species Streptomyces tendae (99,78%). CONCLUSIONS: In the eco-friendly paper bleaching industry, Streptomyces tendae has demonstrated the potential to create enzymes with properties that can be active in a wide range of pH levels. The oligosaccharides have the potential as prebiotics or dietary supplements with anti-cancer properties. Further research is needed to optimize the production, purification, and development of the application of pectinase and xylanase enzymes produced by Actinomycetes isolates.

Correction: Anopheles sundaicus complex and the presence of Anopheles epiroticus in Indonesia.

[This corrects the article DOI: 10.1371/journal.pntd.0008385.].

Anopheles sundaicus complex and the presence of Anopheles epiroticus in Indonesia.

Anopheles sundaicus s.l. is an important malaria vector primarily found in coastal landscapes of western and central Indonesia. The species complex has a wide geographical distribution in South and Southeast Asia and exhibits ecological and behavioural variability over its range. Studies on understanding the distribution of different members in the complex and their bionomics related to malaria transmission might be important guiding more effective vector intervention strategies. Female An. sundaicus s.l. were collected from seven provinces, 12 locations in Indonesia representing Sumatra: North Sumatra, Bangka-Belitung, South Lampung, and Bengkulu; in Java: West Java; and the Lesser Sunda Islands: West Nusa Tenggara and East Nusa Tenggara provinces. Sequencing of ribosomal DNA ITS2 gene fragments and two mitochondrial DNA gene markers, COI and cytb, enabled molecular identification of morphologically indistinguishable members of the complex. Findings allowed inference on the distribution of the An. sundaicus s.l. present in Indonesia and further illustrate the phylogenetic relationships of An. epiroticus within the complex. A total of 370 An. sundaicus s.l specimens were analysed for the ITS2 fragment. The ITS2 sequence alignment revealed two consistent species-specific point mutations, a T>C transition at base 479 and a G>T transversion at base 538 that differentiated five haplotypes: TG, CG, TT, CT, and TY. The TG haplotype matched published An. epiroticus-indicative sequences from Thailand, Vietnam and peninsular Malaysia. The previously described insertion event (base 603) was observed in all identified specimens. Analysis of the COI and cytb genes revealed no consistent nucleotide variations that could definitively distinguish An. epiroticus from other members in the Sundaicus Complex. The findings indicate and support the existence of An. epiroticus in North Sumatra and Bangka-Belitung archipelago. Further studies are recommended to determine the full distributional extent of the Sundaicus complex in Indonesia and investigate the role of these species in malaria transmission.

Isolation and structure elucidation of phenazine derivative from Streptomyces sp. strain UICC B-92 isolated from Neesia altissima (Malvaceae).

BACKGROUND AND OBJECTIVES: Endophytic actinomycetes have been known as a promising source for new antibiotics discovery against susceptible and resistant forms of pathogenic microorganisms. This study was aimed at determining antibacterial compound from Streptomyces sp. strain B-92 isolated from a medicinal plant Neesia altissima. MATERIALS AND METHODS: Streptomyces sp. strain UICC B-92 was endophytic actinomycetes of N. altissima that obtained from Universitas Indonesia Culture Collection (UICC). Isolation and determination of bioactive compound were carried out using thin layer chromatography (TLC), nuclear magnetic resonance spectroscopy (NMR), and liquid chromatography mass spectrometry (LC-MS) analyses. An in vitro antibacterial assay of pure bioactive compound from the endophytic actinomycetes strain was performed against Bacillus cereus strain ATCC 10876, Escherichia coli strain ATCC 25922, Salmonella typhimurium strain ATCC 25241, Shigella flexneri strain ATCC 12022 and Staphylococcus aureus strain ATCC 25923. RESULTS: The bioactive compound was identified as 4-((3S,4R,5S)-3,4,5-trihydroxy-6-(hydroxymethyl) tetrahydro-2H-pyran-2-yloxy) phenazine-1-carboxylic acid. In vitro antimicrobial assay showed that bioactive compound of Streptomyces sp. strain UICC B-92 exhibited antagonistic activities against two Gram-positive bacteria, viz, B. cereus strain ATCC 10876 and S. aureus strain ATCC 25923. CONCLUSION: The findings of this research showed that, bioactive compound of Streptomyces sp. strain UICC B-92 is suggested a new compound based on glycoside structure and its position.

Antibacterial compound produced by Pseudomonas aeruginosa strain UICC B-40, an endophytic bacterium isolated from Neesia altissima.

This study's aim was to determine the identity of antibacterial compounds produced by Pseudomonas aeruginosa strain UICC B-40 and describe the antibacterial compounds' mechanisms of action for damaging pathogenic bacteria cells. Isolation and identification of the compounds were carried out using thin layer chromatography (TLC), nuclear magnetic resonance (NMR) spectroscopy and liquid chromatography mass spectrometry (LC-MS) analyses. Antibacterial activity was assayed via minimum inhibitory concentration (MIC) and the antibacterial compound mechanism was observed morphologically through scanning electron microscopy (SEM). This study successfully identified the (2E,5E)-phenyltetradeca-2,5-dienoate antibacterial compound (molecular weight 300 g/mol), composed of a phenolic ester, fatty acid and long chain of aliphatic group structures. MIC values for this compound were determined at 62.5 µg/ml against Staphylococcus aureus strain ATCC 25923. The mechanism of the compound involved breaking down the bacterial cell walls through the lysis process. The (2E,5E)-phenyltetradeca-2,5-dienoate compound exhibited inhibitory activity on the growth of Gram-positive bacteria.

Diversity and distribution of culturable lactic acid bacterial species in Indonesian Sayur Asin.

BACKGROUND AND OBJECTIVES: Lactic acid bacteria (LAB) play important roles in processing of Sayur Asin (spontaneously fermented mustard). Unfortunately, information about LAB in Indonesian Sayur Asin, prepared by traditional manufactures which is important as baseline data for maintenance of food quality and safety, is unclear. The aim of this study was to describe the diversity and distribution of culturable lactic acid bacteria in Sayur Asin of Indonesia. MATERIALS AND METHODS: Four Sayur Asin samples (fermentation liquor and fermented mustard) were collected at harvesting times (3-7 days after fermentation) from two traditional manufactures in Tulung Agung (TA) and Kediri (KDR), East Java provinces, Indonesia. LAB strains were isolated by using MRS agar method supplemented with 1% CaCO 3 and characterized morphologically. Identification of the strains was performed basedon 16S rDNA analysis and the phylogenetic tree was drawn to understand the phylogenetic relationship of the collected strains. RESULTS: Different profiles were detected in total count of the plates, salinity and pH of fermenting liquor of Sayur Asin in TA and KDR provinces. A total of 172 LAB isolates were successfully isolated and identified based on their 16S rDNA sequences. Phylogenetic analysis of 27 representative LAB strains from Sayur Asin showed that these strains belonged to 5 distinct species namely Lactobacilus farciminis (N=32), L. fermentum (N=4), L. namurensis (N=15), L. plantarum (N=118) and L. parafarraginis (N=1). Strains D5-S-2013 and B4-S-2013 showed a close phylogenetic relationship with L. composti and L. paralimentarius, respectively where as the sequence had slightly lower similarity of lower than 99%, suggesting that they may be classified into novel species and need further investigation due to exhibition of significant differences in their nucleotide sequences. Lactobacillus plantarum was found being dominant in all sayur asin samples. CONCLUSION: Lactobacilli were recognized as the major group of lactic acid bacteria in Sayur Asin including 5 known and 2 novel candidate species. The distribution of LAB species was associated with the manufactures where Sayur Asin is produced.

The local knowledge of medicinal plants trader and diversity of medicinal plants in the Kabanjahe traditional market, North Sumatra, Indonesia.

ETHNOPHARMACOLOGICAL RELEVANCE: Market is the main place for transactions of medicinal plants and traditional ingredients by local community in the Karo regency, North Sumatra, Indonesia. This is the first study to document the local knowledge of traders on and the diversity of the medicinal plants. The investigation was carried out in the Kabanjahe traditional market, in the Karo regency. The research goal was to reveal the local knowledge, diversity and utilization of medicinal plants, which have been traded in the Kabanjahe traditional market, as a basis for conservation efforts. MATERIALS AND METHODS: The study was conducted through ethnobotanical approach using market surveys. All traders of medicinal plants were surveyed applying in-depth interviews and participative observations. Data were analyzed qualitatively using descriptive statistics. The diversity of medicinal plants was expressed in term of the Shannon-Wiener diversity index (H'), whereas the similarity among traders was indicated by Jaccard index (Ji). RESULTS: Traders of medicinal plants stored the simplicia of medicinal plants in chest of drawers, plastic baskets, plastic bags, and in the air by suspending them from the the stall ceilings. We recorded 344 species, 217 genera and 90 families of medicinal plants. Those that were sold mostly belong to Zingeberaceae (20 species), Poaceae (19 species), and Asclepiadaceae (17 species), and the species received high consumers demand, mostly belong to Zingiberaceae, Rutaceae, and Asclepidiaceae. Asclepidiaceae was used to treat diseases like cancer and heart problems. The Shannon-Wiener diversity index of medicinal plants at the Kabanjahe traditional market was high (H'= 5.637). The high Jaccard similarity index (Ji>0.56) suggested that the traders were trading similar species of medicinal plants. CONCLUSION: Kabanjahe traditional market is the center for the sale of of medicinal plants as traditional ingredients. Several species are well known for their pharmacological properties but others, [such as: Dischidia imbricata (Blume) Steud., Dischidia nummularia R.Br., Hoya macrophylla Blume, and Hoya coriacea Blume] have been used for cancer treatment by local communities, but pharmacologically unknown, hence they are promising candidates for further investigation.

Existence of the rdl mutant alleles among the anopheles malaria vector in Indonesia.

BACKGROUND: The gamma-aminobutyric acid (GABA) receptor-chloride channel complex is known to be the target site of dieldrin, a cyclodiene insecticide. GABA-receptors, with a naturally occurring amino acid substitution, A302S/G in the putative ion-channel lining region, confer resistance to cyclodiene insecticides that includes aldrin, chlordane, dieldrin, heptachlor, endrin and endosulphan. METHODS: A total of 154 mosquito samples from 10 provinces of malaria-endemic areas across Indonesia (Aceh, North Sumatra, Bangka Belitung, Lampung, Central Java, East Nusa Tenggara, West Nusa Tenggara, West Sulawesi, Molucca and North Molucca) were obtained and identified by species, using morphological characteristic. The DNA was individually extracted using chelex-ion exchanger and the DNA obtained was used for analyses using sequencing method. RESULTS: Molecular analysis indicated 11% of the total 154 Anopheles samples examined, carried Rdl mutant alleles. All of the alleles were found in homozygous form. Rdl 302S allele was observed in Anopheles vagus (from Central Java, Lampung, and West Nusa Tenggara), Anopheles aconitus (from Central Java), Anopheles barbirostris (from Central Java and Lampung), Anopheles sundaicus (from North Sumatra and Lampung), Anopheles nigerrimus (from North Sumatra), whereas the 302 G allele was only found in Anopheles farauti from Molucca. CONCLUSION: The existence of the Rdl mutant allele indicates that, either insecticide pressure on the Anopheles population in these areas might still be ongoing (though not directly associated with the malaria control programme) or that the mutant form of the Rdl allele is relatively stable in the absence of insecticide. Nonetheless, the finding suggests that integrated pest management is warranted in malaria-endemic areas where insecticides are widely used for other purposes.