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    Unveiling novel Neocosmospora species from Thai mangroves as potent biocontrol agents against Colletotrichum species
    Klomchit, Anthikan; Calabon, Mark S; Worabandit, Sompradtana; Weaver, Jack A; Karima, Elfina M; Alberti, Fabrizio; Greco, Claudio; Mahanil, Siraprapa (Oxford University Press, 2024)
    Aims: Neocosmospora species are saprobes, endophytes, and pathogens belonging to the family Nectriaceae. This study aims to investigate the taxonomy, biosynthetic potential, and application of three newly isolated Neocosmospora species from mangrove habitats in the southern part of Thailand using phylogeny, bioactivity screening, genome sequencing, and bioinformatics analysis. Methods and results: Detailed descriptions, illustrations, and a multi-locus phylogenetic tree with large subunit ribosomal DNA (LSU), internal transcribed spacer (ITS), translation elongation factor 1-alpha (ef1-α), and RNA polymerase II second largest subunit (RPB2) regions showing the placement of three fungal strains, MFLUCC 17-0253, MFLUCC 17-0257, and MFLUCC 17-0259 clustered within the Neocosmospora clade with strong statistical support. Fungal crude extracts of the new species N. mangrovei MFLUCC 17-0253 exhibited strong antifungal activity to control Colletotrichum truncatum CG-0064, while N. ferruginea MFLUCC 17-0259 exhibited only moderate antifungal activity toward C. acutatum CC-0036. Thus, N. mangrovei MFLUCC 17-0253 was sequenced by Oxford nanopore technology. The bioinformatics analysis revealed that 49.17 Mb genome of this fungus harbors 41 potential biosynthetic gene clusters. Conclusion: Two fungal isolates of Neocosmospora and a new species of N. mangrovei were reported in this study. These fungal strains showed activity against pathogenic fungi causing anthracnose in chili. In addition, full genome sequencing and bioinformatics analysis of N. mangrovei MFLUCC 17-0253 were obtained. © 2024 The Author(s). Published by Oxford University Press on behalf of Applied Microbiology International.
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    Transmittance Properties of Healthy and Infected Coffee Robusta Leaves with Coffee Leaf Miner (CLM) Pests
    bulan, Jejomar; Cadondon, Jumar; Lesidan, James Roy; Vallar, Edgar; Galvez, Maria Cecilia (Multidisciplinary Digital Publishing Institute (MDPI), 2023)
    Coffee Robusta (Coffea canephora) increased its total production by 73.5% during the first quarter of 2023. In this study, twenty (20) samples each of healthy and infected coffee leaves were measured for their transmittance properties in the UV-Vis and NIR regions. Coffee Leaf Miner (CLM)-infected leaves were identified based on translucent patches on the plant foliage. The results showed that a healthy coffee leaf has a mean transmittance of 41.53 µW for the NIR region, while for the infected leaves, the mean transmittance is 47.06 µW. Healthy coffee Robusta leaves showed significant differences in their transmittance properties compared to infected coffee Robusta leaves in the UV (r = −0.15, p = 0.021, F = 5.8, t = −0.286), visible (r = −0.15, p = 0.018, F = 6.11, t = −2.88), and NIR (r = −0.14, p = 0.027, F = 5.28, t = −2.99) regions. A CLM index was introduced based on the intensity ratio of green and red wavelengths. I535/575 showed positive correlation with the estimated chlorophyll-a concentration for healthy (r = 0.94, p = 0.227) and infected (r = 0.56, p = 0.622) leaves. This method leads to the development of portable sensors for the early detection of CLM pests in plants. © 2023 by the author. Licensee MDPI, Basel, Switzerland.
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    Zein nanoencapsulation enhances the antifungal activity of thymol for postharvest decay control in bananas
    Punelas–Villanueva, Dana C.; Almeda, Ronaniel A.; Chua, Mari Sherlin S.; Tabor, Rico F.; Vidallon, Mark Louis P.; Rodriguez, Evelyn B. (Springer, 2024)
    The current work describes a nanoparticle system-based approach to enhance the antifungal activity of thymol, a ubiquitous natural antifungal phenolic compound, in postharvest control against banana anthracnose. Thymol was encapsulated within the amphiphilic protein zein by high-shear emulsification, yielding highly dispersible thymol-loaded zein nanoparticles with a high encapsulation efficiency (70%). These particles have an average diameter of 300 nm with spherical morphology, smooth interface, and matrix-type internal structure, as supported by comprehensive structural characterization (dynamic light scattering, transmission electron microscopy and atomic force microscopy). Based on a 40-d storage stability test, thymol was effectively retained within the nanoparticles at 4 °C and ambient room temperature (99% and 97% retention, respectively), despite thymol’s instability and volatility. Antifungal activity assessment against Colletotrichum musae, one of the predominant pathogens that cause banana anthracnose, showed a 200- to 300-fold improvement in the in vitro antifungal activity of thymol. Moreover, the application of thymol-loaded zein nanoparticles as a spray component for banana postharvest treatment demonstrated the efficacy of thymol-loaded zein nanoparticles in preventing and delaying the formation of initial symptoms of banana anthracnose. This appears to arise from the thymol-loaded zein nanoparticles depositing as a film on the banana epidermis, as revealed by atomic force microscopy. Overall, this nanoparticle system offers a new avenue for the design of effective antifungal materials with potential applications in combatting postharvest diseases. Graphical abstract: (Figure presented.)
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    Characterization of porcine skin using a portable time-domain optical coherence tomography system
    Galvez, Maria Cecilia; Cadondon, Jumar; Mandia, Paulito; Macalalad, Ernest; Vallar, Edgar; Shiina, Tatsuo (Multidisciplinary Digital Publishing Institute (MDPI), 2023)
    Optical coherence tomography (OCT) is an imaging tool used to visualize the cross-section of a sample. Additionally, this device can measure the sample’s physical properties. This experiment used a portable version to measure the epidermal thickness and dermal extinction coefficient of porcine skin obtained from different anatomical sites. The thinnest epidermis was found to be from the ear region, while the thickest is from the leg. Meanwhile, the lowest dermal extinction coefficient was from the ear, while the highest was from the belly. These measured properties can be used as aids for diagnosing various skin conditions in humans and animals.
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    Building leaders for the UN Ocean Science Decade: A guide to supporting early career women researchers within academic marine research institutions
    Shellock, R.J.; Cvitanovic, C.; McKinnon, M.C.; Mackay, M.; van Putten, I.E.; Blythe, J.; Kelly, R.; Tuohy, P.; Maltby, K.M.; Mynott, S.; Simmonds, N.; Bailey, M.; Begossi, A.; Crona, B.; Fakoya, K.A.; Ferreira, B.P.; Ferrer, A.J.G.; Frangoudes, K.; Gobin, J.; Goh, H.C.; Haapasaari, P.; Hardesty, B.D.; Häussermann, V.; Hoareau, K.; Hornidge, A.-K.; Isaacs, M.; Kraan, M.; Li, Y.; Liu, M.; Lopes, P.F.M.; Mlakar, M.; Morrison, T.H.; Oxenford, H.A.; Pecl, G.; Penca, J.; Robinson, C.; Selim, S.A.; Skern-Mauritzen, M.; Soejima, K.; Soto, D.; Spalding, A.K.; Vadrot, A.; Vaidianu, N.; Webber, M.; Wisz, M.S. (Oxford University Press, 2023)
    Diverse and inclusive marine research is paramount to addressing ocean sustainability challenges in the 21st century, as envisioned by the UN Decade of Ocean Science for Sustainable Development. Despite increasing efforts to diversify ocean science, women continue to face barriers at various stages of their career, which inhibits their progression to leadership within academic institutions. In this perspective, we draw on the collective experiences of thirty-four global women leaders, bolstered by a narrative review, to identify practical strategies and actions that will help empower early career women researchers to become the leaders of tomorrow. We propose five strategies: (i) create a more inclusive culture, (ii) ensure early and equitable career development opportunities for women ECRs, (iii) ensure equitable access to funding for women ECRs, (iv) offer mentoring opportunities and, (v) create flexible, family-friendly environments. Transformational, meaningful, and lasting change will only be achieved through commitment and collaborative action across various scales and by multiple stakeholders.
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    Dominant bacterial pathogens in a river receiving swine farm effluent
    Malaya, Michaela Marie D.; Gito, Mary Ann G.; De la Cruz, Kyla Kris A.; Caipang, Christopher Marlowe A. (Parnam Publication Co., 2024)
    Swine production dominates the livestock sector in the Philippines, providing 60% of the nation’s meat supply. Some of the swine industry’s challenges include waste management, resulting in environmental issues such as air pollution, water contamination, and the spread of pathogens that can affect human health. Severe impacts of swine waste on water bodies can lead to eutrophication and render water systems unproductive. This study aimed to isolate and characterize the dominant bacterial pathogens in swine waste effluent in a municipality in southern Iloilo, Philippines. Water samples from the receiving river were collected and cultured to isolate bacteria, followed by genetic identification and phylogenetic analysis to understand the microbial contamination in rivers impacted by the swine farm. Four dominant bacterial strains were isolated and identified using 16S rRNA gene sequencing. All strains, confirmed as Gram-negative, belong to the Enterobacteriaceae family, specifically Klebsiella pneumoniae and Enterobacter cloacae. K. pneumoniae, highly resistant and associated with significant health risks, is found in diverse environments and causes severe infections. E. cloacae, an opportunistic pathogen, contributes to water contamination and antibiotic resistance. The study underscores the environmental and public health concerns linked to these bacteria, emphasizing the need for stringent waste management and infection control strategies. © 2024, Parnam Publication Co.. All rights reserved.
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    Lactational changes in Filipino human milk oligosaccharides reveal maternal secretor status
    Albaladejo, Anthony Salvador B.; Nacario, Ruel C.; Navarro, Baby Richard R.; Lebrilla, Carlito B.; Completo, Gladys C. (Wiley, 2023)
    Background: Breast milk contains human milk oligosaccharides (HMOs), which are the third most abundant solid component and are considered indigestible with no nutritional value to infants. However, HMOs provide protection against pathogens, support gut bacteria, and aid in brain development. This study investigated the relationship between HMOs and secretor status and tracked changes in HMO levels throughout lactation. The study employed a rapid-throughput extraction method, nano-HPLC Chip/TOF-MS analysis, and an annotated HMO structure library for oligosaccharide analysis. Results: Results from the study revealed that 81% of Filipino mothers (N = 155) are secretors, while 19% are non-secretors. The total HMO abundance significantly decreased (p = 0.0001) throughout lactation but was significantly (p = 0.0390) higher in colostrum compared with mature milk. The total fucosylated HMOs had a significantly (p = 0.0460) lower absolute abundance, while the total sialylated HMOs showed a significantly (p = 0.0012) higher abundance in colostrum relative to mature milk. Non-fucosylated neutral HMOs showed no significant (p = 0.1040) difference in abundance between colostrum and mature milk. Conclusion: This is the first comprehensive data on the maternal secretor status of Filipino mothers, showing the decrease in total HMO abundance throughout lactation and differences in the abundances of various oligosaccharide types between colostrum and mature milk.
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    Seafarers’ mental health during the COVID-19 pandemic: An examination of current supportive measures and their perceived effectiveness
    Tang, Lijun; Abila, Sanley; Kitada, Momoko; Malecosio, Serafin; Montes, Karima Krista (Elsevier, 2022)
    As the current COVID-19 pandemic and the resulting crew change crisis exacerbates the mental health problem faced by seafarers, various maritime stakeholders have mobilised their resources and strengths to provide a variety of supportive measures to address the issue. This paper aims to find out what measures have been adopted in the industry and how widely they have been experienced/received by seafarers and evaluate their effectiveness. To achieve this aim, this research employed a mixed methods design involving qualitative interviews with 26 stakeholders and a quantitative questionnaire survey of 817 seafarers. The research identified a total number of 22 mental health support measures, all of which were perceived to have contributed positively to seafarers’ mental health. However, not all of them were widely available to or utilised by seafarers. The findings also highlighted the importance of family, colleagues, shipping companies, and government agencies, as they are associated with the most effective support measures, namely communication with family, timely crew changes, being prioritised for vaccination, being vaccinated, and a positive and collegial atmosphere on-board. Based on the findings, recommendations are provided.
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    Stock market returns and climate risk in the U.S.
    Chen, Yiyang; Mamon, Rogemar; Spagnolo, Fabio; Spagnolo, Nicola (Elsevier, 2025)
    Using a data set for all companies forming the S&P 500 index, we investigate the stock price responses to acute physical risks, chronic physical risks, and transition risks. Our findings reveal that certain sectors are more vulnerable to climate risks, whereas others appear to be relatively unaffected. In addition, our results show that listed firms with poor environmental performance scores are more exposed to climate risk, as indicated by their stock returns being negatively affected, compared to firms with higher environmental performance scores. This suggests that improving environmental performance may help companies to better cope with climate risks and improve their financial performances. Our analysis provides evidence that the short-term systematic risk is more vulnerable to the climate risk events, whereas effects on long-term systematic risk do not appear to be statistically significant. These findings indicate that investors and firms should pay a particular attention to short-term systematic risk when considering the potential impact of climate risk on stock market performances.
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    Algal organic matter fluorescence analysis of Chlorella sp. for biomass estimation
    Cadondon, Jumar; Lesidan, James Roy; Bulan, Jejomar; Vallar, Edgar; Shiina, Tatsuo; Galvez, Maria Cecilia (Multidisciplinary Digital Publishing Institute (MDPI), 2023-11-15)
    Algal Organic Matter (AOM) is derived from the dissolved organic matter composition of the algal species being observed. In this study, excitation–emission fluorescence spectroscopy was used to determine Chlorella sp.’s AOM and pigment characteristics in varying algal biomass concentrations. The AOM and pigment characteristics were observed at 400–600 nm and 600–800 nm fluorescence emission, respectively, with an excitation spectrum of 300–450 nm. F450/680 was computed based on the ratio between the dissolved organic matter contribution at 450 nm and chlorophyll-a at 680 nm. F450/680 positively correlated with algal biomass (r = 0.96) at an excitation wavelength of 405 nm. This study is a good reference for those interested in algal biomass estimation and production in natural waters.