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Background The hydrophobic nature of hydrocarbons make them less bioavailable to microbes, generally leading to low efficiency in biodegradation. Current bioremediation strategies for hydrocarbon contamination, uses induced mixed microbial cultures. This in-vitro study demonstrates the utilization of naturally occurring communities in suitable habitats for achieving highly efficient, synergistic degradation of hydrocarbons in a simple community structure without additives. Methods Enrichment media supplemented with 1% (7652.53 mg/L) hexadecane (HXD) as the sole carbon source were inoculated with samples of soil with waste polythene, collected from a municipal landfill in order to isolate microbial communities. Gas Chromatography-Mass Spectrometry (GC-MS) analysis was performed on HXD grown co-cultures and individual counterparts after 14 days incubation and percentage degradation was calculated. Microbes were identified using 16S rRNA gene and Internal Transcribed Spacer region sequencing. Biofilm formation was confirmed through scanning electron microscopy, in the most efficient community. Results Three mixed communities (C1, C2 and C3) that demonstrated efficient visual disintegration of the HXD layer in the static liquid cultures were isolated. The C1 community showed the highest activity, degrading > 99% HXD within 14 days. C1 comprised of a single fungus and a bacterium and they were identified as a Bacillus sp. MM1 and an Apsergillus sp. MM1. The co-culture and individual counterparts of the C1 community were assayed for HXD degradation by GC-MS. Degradation by the fungal and bacterial monocultures were 52.92 ± 8.81% and 9.62 ± 0.71% respectively, compared to 99.42 ± 0.38% by the co-culture in 14 days. This proved the synergistic behavior of the community. Further, this community demonstrated the formation of a biofilm in oil-water interface in the liquid medium. This was evidenced from scanning electron microscopy (SEM) showing the Bacillus cells attached on to Aspergillus mycelia. Conclusions This study demonstrates the utilization of naturally formed fungal-bacterial communities for enhanced biodegradation of hydrocarbons such as hexadecane and reports for the first time, synergistic degradation of hexadecane through biofilm formation, by a community comprising of Bacillus cereus group and Aspergillus flavus complex. Electronic supplementary material The online version of this article (10.1186/s12866-019-1460-4) contains supplementary material, which is available to authorized users.

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INTRODUCTIONForensic art is a technique used by law enforcement in order to identify a suspect towards apprehension or conviction of wanted persons and composite art is one branch. A "facial composite" is a graphical representation of a human face according to eyewitnesses' description. The failure rate of suspect identification through manual facial composite sketch was reportedly quite high in 2014 in Sri Lanka 1 . In addition, international software available for face identification may not be the best approach for Sri Lankan population. OBJECTIVETo develop an automated, image processing based computer software solution using 2D facial feature templates for suspect identification in Sri Lanka. STUDY DESIGNFacial feature templates were constructed by analyzing a dataset from Sri Lankan young adult population focusing on most occurring facial indices and commonly available facial feature shapes. Anthropometric proportion indices measurements and shape classification for eyes, nose, face, upper vermilion and lower vermilion of 140 undergraduates of both sexes between 20-25 age were identified and categorized according to BMI (Body Mass Index). Face Software Development Kit library (Face SDK library) was used for index measurements and domain expert knowledge from aesthetic and forensic art fields were utilized in identifying facial feature shapes. These parameters were incorporated to construct 2D facial feature templates for major facial feature. Then these templates were transferred into the system to be used for composite construction purpose. Finally face visualization process will perform iteratively until the eyewitness is satisfied with the ultimate image. Evaluation of this solution with face pool technique and anthropometric index evaluation techniques obtained 70.19% accuracy and average of 84% respectively. CONCLUSIONA significant accuracy level in composite images has been obtained by using anthropometric indices measurements. Hence, this computerized solution will significantly enhance the currently used manual facial composite procedure for suspect identification in Sri Lanka ensuring justice to the victim of crime. FORENSIC ART: 2D FACIAL COMPOSITE THROUGH IMAGE PROCESSING TECHNIQUES IN SRI LANKA

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Efficient degradation of alkanes in crude oil by the isolated Aspergillus flavus MM1 alluded to the presence of highly active alkane-degrading enzymes in this fungus. A long-chain alkane-degrading, LadA-like enzyme family in A. flavus was identified, and possible substrate-binding modes were analyzed using a computational approach. By analyzing publicly available protein databases, we identified six uncharacterized proteins in A. flavus NRRL 3357, of which five were identified as class LadAα and one as class LadAβ, which are eukaryotic homologs of bacterial long-chain alkane monooxygenase (LadA). Computational models of A. flavus LadAα homologs (Af1-Af5) showed overall structural similarity to the bacterial LadA and the unique sequence and structural elements that bind the cofactor Flavin mononucleotide (FMN). A receptor-cofactor-substrate docking protocol was established and validated to demonstrate the substrate binding in the A. flavus LadAα homologs. The modeled Af1, Af3, Af4, and Af5 captured long-chain n-alkanes inside the active pocket, above the bound FMN. Isoalloxazine ring of reduced FMN formed a π–alkyl interaction with the terminal carbon atom of captured alkanes, C16–C30, in Af3–Af5 and C16–C24 in Af1. Our results confirmed the ability of identified A. flavus LadAα monooxygenases to bind long-chain alkanes inside the active pocket. Hence A. flavus LadAα monooxygenases potentially initiate the degradation of long-chain alkanes by oxidizing bound long-chain alkanes into their corresponding alcohol.