Orangutan Tapanuli ( Pongo tapanuliensis ) is one of the three recognized orangutan species, classified as Critically Endangered, and is found exclusively in the tropical rainforest ecosystem of Batang Toru, North Sumatra. One of the key behaviors of orangutans is daily nest-building in specific trees for resting purposes. This study aims to identify the species and structural characteristics of trees used as nesting sites by the Orangutan Tapanuli at the Camp Mayang Research Station. Data were collected through direct field observations conducted from 2023 to 2025, recording tree species, diameter at breast height (DBH), tree height, and nest height above ground level. The results show that among the 95 nests observed, 17 tree species from 15 families were used, with Palaquium hexandrum (Sapotaceae) being the most frequently used nest tree (20%). Common characteristics of selected nest trees include large DBH (>40 cm), an average height of 21.7 meters, and strong horizontal branching. These findings suggest that nest tree selection by orangutans is more strongly influenced by the functional structural traits of the trees rather than by availability or taxonomic identity alone. This result is critical to support species conservation efforts by prioritizing the protection of key tree species preferred for nesting, thereby helping to ensure the sustainability of suitable habitat for the Orangutan Tapanuli.
Listeria monocytogenes, a bacterium responsible for listeriosis, is an environmental and food-borne pathogen that poses a particular risk to pregnant women and the elderly. While traditionally associated with animal products, ready-to-eat salads are increasingly recognised as a source of Listeria outbreaks. However, little is known about the potential virulence of Listeria isolates from the fresh produce environment. This study assessed the virulence potential of nine L. monocytogenes strains from the fresh produce chain using the Galleria mellonella invertebrate infection model. Larvae were infected with 106 CFU of each strain via their circulatory system and compared to a reference strain L. monocytogenes (EGD-e) and Listeria ivanovii. Virulence was evaluated by measuring mortality rates, health index score of larvae, viable bacterial counts in the larvae, and the larvae’s immune. Significant differences in larval mortality were observed among strains. Strains NLmo4 and NLmo5 caused the highest mortality rates (98.8% and 96.7%, respectively at 7 days post-infection), while strain NLmo20 had a significantly lower mortality rate of 65% at the same time point (p<0.05). Six isolates that caused varied mortality rates were then selected and tested for their ability to replicate both in vitro and in vivo and their impact on larval haemocyte density. In vitro growth rates were not significantly different among L. monocytogenes strains or compared to Listeria ivanovii. However, L. monocytogenes strains persisted and replicated in larvae up to 7d days post-infection, whereas Listeria ivanovii was reduced by 5 logs CFU by day 7. The presence of these L. monocytogenes strains caused organ damage in larvae, indicated by increased melanisation and subsequent larval death. Haemocyte density showed insignificant fluctuations following infection. In conclusion, the results of this study suggest L. monocytogenes strains from fresh produce food chain have varying pathogenicity levels and can pose potential risk to human health.
Mangrove forests, benefitting millions of people, experience significant degradation. Global recognition of the urgency of halting and reversing this trend have initiated numerous restoration activities. Restoration success is typically evaluated by estimating mangrove survival and area restored, while diversity and structure of vegetation, as proxies for functional forests, are rarely considered. Here we assess mangrove species richness along sea‐landward transects and evaluate restoration outcomes by comparing number of mangrove species, relative species abundance, biomass, diameter, and canopy cover in “Monoculture Reforestation”, “Mixed Species Regeneration” and adjacent “Reference” forest stands, 14 (Tiwoho site) and 16 years (Likupang site) after restoration activities took place. In the “Monoculture Reforestation” plots, mangrove diversity and structure still closely reflected the original restoration actions, with only one and two “new” species having established among the originally densely planted “foundation” species. In contrast, the “Mixed Species Regeneration” plots were more similar to the “Reference” plots in terms of tree diameter and canopy coverage, but species number, abundance and biomass were still lower. The trajectory of the “Mixed Species Regeneration” plots suggests their similarity with the “Reference” stands will increase over time, whereas such “smooth” transition is unlikely to happen in the planted “Monoculture Reforestation” stands, in the foreseeable future. Implementing frequent small‐scale disturbances in restored forest management would increase stand structure and diversity, accelerating the establishment of a more natural, and likely more functional and resilient forest.
This paper presents a pioneering experimental proof-of-concept study to validate a novel concept of prestress technology that used only pure bio-based composite materials while achieved consistent prestressed stress distribution within the structure member, and provided in-situ flexibility, improved structural performance, and maximised the rate of utilisation of each material. Industrial level of facilities were used during this development. The prestress is achieved by pressurised/forced lamination of multiple components with different materials and geometrical properties. The prestressing process is activated during the pressure release stage during which the components are interacting with each other, creating different stress statuses that would favour the weaker and adverse the stronger components to maximise the strength exploitation of different materials. Using laminated bamboo and timber as an example pair, twenty-two glulam, non-prestressed and prestressed laminated bambootimber composite beams were manufactured, tested, and analysed to provide an in-depth understanding of the structural behaviours of these novel structural members. Failure modes, yielding, ultimate and serviceability limit loads, and corresponding deflections, as well as the histories of strain development at key positions of the specimens were examined. The experimental study confirmed the feasibility, effectiveness and industrial scal-ability of the proposed technology. The novel concept provides a new approach for developing the prestress technology for bio-based materials, and this experimental study laid the foundation for its future analytical development and numerical studies.
Mangroves are complex, unique, and dynamic ecosystems that host organisms that have special physiological adaptations to fluctuations in salinity, temperature, and pH. Gastropods have an important role in the mangrove ecosystem for food cycles and webs by helping to provide nutrients and micro-habitats for microbes. Micro-fungi isolated from mangrove ecosystems are productive sources of enzymes and bioactive compounds such as antibacterial and antifungal. In this study a explored the enzymatic and anti-vibrio activity of fungi associated with the marine gastropod Cerithidea cingulata and Lottia scabra. collected in three mangrove forests in North Sulawesi, Indonesia. The fungi associated with the specimens were inoculated on malt extract agar (MEA) using the tapping method. Enzymatic and anti-vibrio assays were conducted applying the plug method. Positive effects of the fungal compounds on Vibrio were indicated by clear zones formed around the isolates. A total of 13 fungal species were isolated from C. cingulata (19MB-C5 and 19MBa-A4) and L. scabra (19MT-07 and 19MT-18). Most fungal isolates have moderate growth rate. The isolate with highest cellulolytic, proteolytic, and anti-vibriosis activity (Vibrio parahaemolyticus, V. harveyi, V. vulnificus, and V. alginolyticus), derived from C. cingulata 19MB-C5 was closely related to Aspergillus niger, as revealed by molecular analysis using the universal primers ITS1 and ITS4 (similarity value 99%). A. niger 19MB-C5-3 has potential as a bioremediation and anti-vibrio agent that can be applied in aquaculture.
The objective of this work was to identify microbial communities associated with the surfaces of alkali feldspars and to determine whether these microbes might be involved in the weathering of these rocks for agronomic benefit. Samples were taken from weathering profiles and soils developed on a syenite, considered as a raw material for agromineral production, located in the municipality of Triunfo, in the state of Pernambuco, Brazil. Molecular microbiological techniques (qPCR and 16S rRNA gene sequencing) were used, and data were interpreted by the analysis of variance, hierarchical cluster analysis, and principal coordinates analysis. In addition, scanning electron microscopy was used to image mineral surfaces. Similar bacterial communities were observed in all samples, showing that the bacteria found in soil are present at the earliest stages of rock weathering and are available to play a role in nutrient release. In particular, Actinobacteria and, within this phylum, Actinomycetales were proportionally more abundant than other taxa in rock-dominated soil samples, i.e., in thin soils on or between fractured or broken syenite. The analysis of rock dust used as a remineralizer, crushed with no further treatment, shows that Actinobacteria play a role in the early stages of weathering of feldspar-bearing rocks.
In the previous study, we examined the effect of silver nanoparticles (AgNPs) on beneficial soil fungus including Trichoderma harzianum (T22), and pathogenic soil-borne fungus, Rhizoctonia solani (AG3-PT). The result exhibited that T. harzianum (T22) is tolerance towards AgNPs. On the other hand, the pathogenic fungi, R.solani (AG3-PT), is more sensitive to AgNPs. T. harzianum is well known as biocontrol agent to suppress R. solani. Therefore, in this study we investigated the combination of T. harzianum (T22) and AgNPs at low concentration to control two strains of R. solani (AG3-PT and AG2-1). The effect of AgNPs at two different levels (20 mg L-1 and 50 mg L-1) was examined over the growth of the two strains of R. solani and T. harzianum (T22) using dual culture technique. The results shows that this combination have a potential to reduce colony growth of R. solani (AG2-1) at higher AgNPs concentration. However, it was not the case for R. solani (AG3-PT). It can be concluded that AgNPs toxicity depend on several factors including species strain and the size of AgNPs particle.
Abstract. Trianto A, Radjasa OK, Subagiyo, Purnaweni H, Bahry MS, Djamaludin R, Tjoa A, Singleton I, Diele K, Evan D. 2021. Potential of fungi isolated from a mangrove ecosystem in Northern Sulawesi, Indonesia: Protease, cellulase and anti-microbial capabilities. Biodiversitas 22: 1717- 1724. The high and relatively unexplored diversity of fungi present in the mangrove ecosystem represents a source of novel biotechnological importance. This study explored the potential of fungi isolated from the mangrove ecosystems to produce proteases and cellulases (commercially important enzymes) and their ability to inhibit pathogenic Vibrio species. Random samples of root, branch, leaf, sediments and litters were collected from 5 different mangrove sites in Manado, North Sulawesi, as a source of fungal isolates. The fungi were isolated on malt extract agar (MEA) and potato dextrose agar (PDA). The isolates were identified mainly based on the molecular methods (18S gene sequence) and examined for their ability to produce proteases, cellulases, and activity against several Vibrio species. Altogether 288 species of fungi were isolated from all samples. The fungi, isolated from leaves showed the highest diversity. A fungal isolate 19 Mba-C2-1 Fusarium equiseti from Avicennia sp. leaf showed the highest protease activity. While, the isolate 19 MT-05-3 Hypocrea sp. from sediment had the highest cellulase activity. From the root of Rhizophora sp., the isolate 19 MT-04-3 identified as Trichoderma viride had the strongest activity against a range of Vibrio species. This work indicates the high potential of fungi isolated from mangrove ecosystems as a source of commercially important enzymes and novel antimicrobial compounds.
Silver nanoparticles (AgNPs) have known anti-microbial properties and therefore have the potential to be used to control fungal plant pathogens. In this study we investigated the growth of a plant pathogenic fungus, Rhizoctonia solani (AG3-PT) in the presence of AgNPs. The effect of AgNPs at two different levels (20 and 50 mg L-1) on hyphal growth and sclerotium production and viability in R. solani was investigated. The results showed that at 20 mg AgNPs L-1 R. solani hyphal growth was reduced along with the production of sclerotia. The results indicate that AgNPs have the potential to control R. solani growth and subsequent development of plant disease symptoms.
Silver nanoparticles (AgNPs) are widely used in industry due to their anti-microbial properties. Despite of its beneficial, they may potentially affect the activity of beneficial soil microorganisms. Trichoderma harzianum was used in this to investigate the effect of AgNPs on beneficial soil fungi. Colony diameter and spore production of T. harzianum were observed in the presence of three levels of AgNPs (200, 600, 1000 mg L−1) in growth media. The results showed that the application of AgNPs at high levels reduced colony diameter and spore production of the tested fungi. The findings indicate that AgNPs have the potential to damage beneficial soil fungi.
The increasing use of silver nanoparticles (AgNPs) due to its excellent antimicrobial activity in commercial products prompting concerns about their fate in the environment. The toxicity of AgNPs is mainly the result of Ag+ ions. In this study, soil was experimentally contaminated with 100 mg kg-1 of AgNO3 to investigate its effect on fungal soil community. Deoxyribonucleic acid (DNA) from the soil was extracted at the 6th, 12th, and 24th month of observation and assessed by Illumina Next Generation Sequencing (NGS). The results show that, the pollutant change fungal community in soil. After 12 months incubated the number of fungal species in the soil reduced significantly and 40% of the community was dominated by one species.
We developed a top-down strategy to characterize an antimicrobial, oxidizing sanitizer, which has diverse proposed applications including surface-sanitization of fresh foods, and with benefits for water resilience. The strategy involved finding quenchers of antimicrobial activity then antimicrobial mode of action, by identifying key chemical reaction partners starting from complex matrices, narrowing down reactivity to specific organic molecules within cells. The sanitizer electrolyzed-water (EW) retained partial fungicidal activity against the food-spoilage fungusAspergillus nigerat high levels of added soils (30-750 mg mL(-1)), commonly associated with harvested produce. Soil with high organic load (98 mg g(-1)) gave stronger EW inactivation. Marked inactivation by a complex organics mix (YEPD medium) was linked to its protein-rich components. Addition of pure proteins or amino acids (<= 1 mg mL(-1)) fully suppressed EW activity. Mechanism was interrogated further with the yeast model, corroborating marked suppression of EW action by the amino acid methionine. Pre-culture with methionine increased resistance to EW, sodium hypochlorite, or chlorine-free ozonated water. Overexpression of methionine sulfoxide reductases (which reduce oxidized methionine) protected against EW. Fluoroprobe-based analyses indicated that methionine and cysteine inactivate free chlorine species in EW. Intracellular methionine oxidation can disturb cellular FeS-clusters and we showed that EW treatment impairs FeS-enzyme activity. The study establishes the value of a top-down approach for multi-level characterization of sanitizer efficacy and action. The results reveal proteins and amino acids as key quenchers of EW activity and, among the amino acids, the importance of methionine oxidation and FeS-cluster damage for antimicrobial mode-of-action.
A Delorme's procedure perineal surgical repair was performed in a wild adult male Sumatran orangutan (Pongo abelii) with a chronic persistent rectal prolapse that had been unsuccessfully treated by 6 previous surgeries. The rectal prolapse did not recur, and the orangutan was successfully released to the wild, 6 weeks later.
Designed as a new method to facilitate the reintroduction and post-release monitoring of orangutans and other apes, implanted radio-telemetry (IRT) was developed and first deployed in 2009. Since that time, it has been necessary to collate and review information on its uptake and general efficacy to inform its ongoing development and that of other emerging tracking technologies. We present here technical specifications and the surgical procedure used to implant miniaturized radio transmitters, as well as a formal testing procedure for measuring detectable transmission distances of implanted devices. Feedback from IRT practitioners (veterinarians and field managers) was gathered through questionnaires and is also presented. To date, IRT has been used in at least 250 individual animals (mainly orangutans) from four species of ape in both Asia and Africa. Median surgical and wound healing times were 30 min and 15 days, respectively, with implants needing to be removed on at least 36 separate occasions. Confirmed failures within the first year of operation were 18.1%, while longer distances were reported from positions of higher elevation relative to the focal animal. IRT has been a transformational technology in facilitating the relocation of apes after their release, resulting in much larger amounts of post-release data collection than ever before. It is crucial however, that implant casings are strengthened to prevent the requirement for recapture and removal surgeries, especially for gradually adapting apes. As with all emerging technological solutions, IRT carries with it inherent risk, especially so due to the requirement for subcutaneous implantation. These risks must, however, be balanced with the realities of releasing an animal with no means of relocation, as has historically been, and is still, the case with orangutans and gorillas.
Global food security remains one of the most important challenges that needs to be addressed to ensure the increasing demand for food of the fast growing human population is satisfied. Fruits and vegetables comprise an essential component of a healthy balanced diet as they are the major source of both macro- and micronutrients. They are particularly important for communities in developing countries whose nutrition often relies solely on a plant-based diet. Recent advances in agriculture and food processing technologies have facilitated production of fresh, nutritious and safe food for consumers. However, despite the development of sophisticated chemical and physical methods of food and equipment disinfection, fresh-cut produce and fruit juice industry still faces significant economic losses due to microbial spoilage. Furthermore, fresh produce remains an important source of pathogens that have been causing outbreaks of human illness worldwide. This chapter characterizes common spoilage and human pathogenic microorganisms associated with fresh-cut produce and fruit juice products, and discusses the methods and technology that have been developed and utilized over the years to combat them. Substantial attention is given to highlight advantages and disadvantages of using these methods to reduce microbial spoilage and their efficacy to eliminate human pathogenic microbes associated with consumption of fresh-cut produce and fruit juice products.
Simon V. Averya,*, Ian Singletonb, Naresh Maganc, Gustavo Goldmand Affiliations: aUniversity of Nottingham, School of Life Sciences, University Park, Nottingham NG7 2RD, UK bEdinburgh Napier University, School of Applied Sciences, Sighthill Court, Edinburgh EH11 4BN, UK cCranfield University, Applied Mycology Group, Cranfield MK43 0AL, UK dUniversity of São Paulo, Dept. Ciencias Farmaceut., BR-14040903 Ribeirão Preto, SP, Brazil
Listeria monocytogenes is sporadically detected on a range of ready to eat fresh produce lines, such as spinach and rocket, and is a threat to public health. However, little is known about the diversity of L. monocytogenes present on fresh produce and their potential pathogenicity. In this work, fifteen Listeria monocytogenes isolates from the UK fresh produce supply chain were characterised using whole genome sequencing (WGS). Additionally, isolates were characterised based on their ability to form biofilm. Whole genome sequencing data was used to determine the sequence type of isolates based on multi-locus sequence typing (MLST), construct a core single nucleotide polymorphism (SNP) phylogeny and determine the presence of virulence and resistance associated genes. MLST revealed 9 distinct sequence types (STs) spanning 2 lineages (I & II) with one isolate belonging to the ST6 subtype, strains from which have been recently implicated in two large, food-associated L. monocytogenes outbreaks in South Africa and across Europe. Although most of the 15 isolates were different, comparison of core genome SNPs showed 4 pairs of 'indistinguishable' strains (<5 SNPs difference). Virulence profiling revealed that some isolates completely lacked the Listeria pathogenicity island-3 (LIPI-3) amongst other virulence factors. Investigation of the inlA gene showed that no strains in this study contained a premature stop codon (PMSC), an indicator of attenuated virulence. Assessment of biofilm production showed that isolates found in the fresh produce supply chain differ in their ability to form biofilm. This trait is considered important for L. monocytogenes to persist in environments associated with food production and processing. Overall the work indicates that a genetically diverse range of L. monocytogenes strains is present in the UK fresh produce supply chain and the virulence profiles found suggests that at least some of the strains are capable of causing human illness. Interestingly, the presence of some genetically indistinguishable isolates within the 15 isolates examined suggests that cross-contamination in the fresh produce environment does occur. These findings have useful implications in terms of food safety and for informing microbial surveillance programmes in the UK fresh produce supply chain.
Fungi threaten the security of food supply to human populations on several fronts. They destroy up to 30 % of crop products through disease and spoilage processes, while mycotoxin-producing fungi and opportunistic pathogens endanger food safety. Control of these fungi is vital for improving food security, but current measures are inadequate and further challenges due to human-population growth and climate change are escalating. Investment and innovation in research on strategies to control fungal growth, harnessed through international, inter-disciplinary collaboration across socio-economic boundaries, provides one key to rising to this challenge.
Listeria monocytogenes is an intracellular human pathogen which enters the body through contaminated food stuffs and is known to contaminate fresh leafy produce such as spinach, lettuce and rocket. Routinely, fresh leafy produce is grown and processed on a large scale before reaching the consumer through various products such as sandwiches and prepared salads. From farm to fork, the fresh leafy produce supply chain (FLPSC) is complex and contains a diverse range of environments where L. monocytogenes is sporadically detected during routine sampling of produce and processing areas. This review describes sources of the bacteria in the FLPSC and outlines the physiological and molecular mechanisms behind its survival in the different environments associated with growing and processing fresh produce. Finally, current methods of source tracking the bacteria in the context of the food supply chain are discussed with emphasis on how these methods can provide additional, valuable information on the risk that L. monocytogenes isolates pose to the consumer.