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Osano, A.

Publications and source records attributed to Osano, A..

7 recordsLinked to original sources
bioRxiv2026

GC-MS Profiling of Compounds produced by endophytic fungi ex-situ and from their host plants, Azadirachta indica and Melia azedarach collected in Kenya, Africa

Endophytic fungi residing within medicinal plants are emerging as prolific sources of structurally diverse bioactive secondary metabolites with applications in drug discovery. Azadirachta indica (Neem) and Melia azedarach (Melia), members of the Meliaceae family, are renowned for their rich phytochemical composition; however, the contribution of their endophytic fungi communities to this chemical diversity remains largely unexplored. Herein, endophytic fungi were isolated from leaves and bark of Neem and Melia collected in Kenya and cultured under distinct physical conditions, solid (plates) and liquid (broth) media to assess how culture environment influences compound production. Compounds were extracted and analyzed using gas chromatography-mass spectrometry (GCMS) to profile the chemical diversity associated with each endophytic fungi, physical culturing state and host plant. GCMS analysis revealed that while the host plant identity influences the presence of specific compounds, the dominant determinant of chemical diversity was intrinsic biosynthetic capacity of the endophytic fungi themselves. Several compounds were unique to endophytic fungi cultures, highlighting their role as independent sources of bioactive compounds. Culture conditions moderately influence metabolite profiles, demonstrating the importance of optimizing growth environments in experimental design and natural product bioprospecting. From the Neem samples, we found 53 compounds uniquely present in the broth samples (consisting of Neem powder and endophytic fungi), 22 found exclusively with the endophytic fungi from the Neem, and 31 compounds shared between the broth and the endophytic fungi samples. In Melia samples, 109 compounds were uniquely present in broth samples from Melia plant (consisting of Melia powder and endophytic fungi), 22 compounds were found exclusively with the endophytic fungi from the Melia, and 55 were shared between the broth and the endophytic fungi samples. Our comparative analysis assessed the Neem and Melia endophytic fungi exclusive samples and reported 12 shared compounds. 10 compounds were unique to Neem and 10 unique to Melia; however, their identities varied between the two categories. While GCMS enabled the identification of volatile and semi-volatile metabolites, future studies employing complementary metabolomic approaches, such as liquid chromatography-mass spectrometry (LCMS), ultra-high-performance liquid chromatography MS/MS (UHPLC MS/MS), or nuclear magnetic resonance (NMR) spectroscopy, would expand coverage to non-volatile, polar, and high molecular weight compounds, providing a more comprehensive understanding of endophyte-derived chemical diversity. These findings provide insights into the interplay between medicinal plants and their endophytes and establish a foundation for leveraging endophytic fungi from Neem and Melia as scalable sources of structurally complex natural products for pharmaceutical and biotechnological applications while minimizing ecological impact.

plant biology↗
bioRxiv2026

GC-MS Based Comparative Metabolomics of Host Plants and Insect Gut Extracts

Herbivorous insects exhibit pronounced metabolic plasticity, enabling adaptation to diverse host plants which complicates pest management strategies. Understanding how plant metabolites are transformed during insect digestion is critical for elucidating plant-insect interactions. We combined gas chromatography-mass spectrometry (GC-MS)-based untargeted metabolomics with UV-Vis quantification of total phenols and flavonoids to compare host plant tissues and insect gut extracts in three systems: fall armyworm (Spodoptera frugiperda) larvae on maize (Zea mays), silkworm (Bombyx mori) on mulberry (Morus alba) and desert locust (Schistocerca gregaria) on wheatgrass (Triticum aestivum). UV-Vis analysis revealed consistent enrichment of total phenols in insect gut relative to host plants ([~]1.4-.35-fold), while flavonoids were reduced ([~]2-7-fold). GC-MS analyses showed clear separation of gut and plant metabolomes, with <35% shared metabolites and the majority unique to insect guts. Insect extracts were enriched in hydrocarbons, fatty acids, sterols, and terpenoid derivatives, reflecting extensive biochemical transformation. Sex-specific metabolite differences were observed in silkworm and desert locust guts despite identical diets. These findings indicate that herbivorous insect guts act as dynamic biochemical reactors, selectively restructuring plant metabolomes through flavonoid turnover, phenolic enrichment, sterol bioconversion, and lipid assimilation. This conserved metabolic strategy across phylogenetically distinct insects underscores adaptive mechanisms for nutrient acquisition and detoxification, a pathway that can be exploited in plant pest control.

plant biology↗
bioRxiv2025

Gravity-Dependent Metabolomic Responses in Starbor Kale Brassica oleracea: Comparisons With Simulated Microgravity Versus Gravity Grown

As science continues to push the frontiers on the length of space flight, we begin to experience an enhanced need for food that is nutritionally dense. Nasa-grants have worked to explore the ability of growing superfoods in space on aircrafts. However, it is paramount to ensure the physiological health of the plants being grown in space flight, perform relatively similar to the plants that grow on earth. An aspect which needs to be further probed is the comparison of microgravity and gravity on the plants seeking to be grown in space flight. Within this NASA-funded research, we grew a superfood vegetable, Kale. The kale was grown in simulated microgravity environments to mimic life in outer space. This simulation was induced by means of a 2-D clinostat. Additionally, kale was grown in gravity conditions as well. We used multivariate statistical tools such as Principal Component Analysis (PCA), together with differential-expression visualizations like volcano plots, to summarize complex data rendered from LC-MS. In this study, we used these approaches to examine how horizontal and vertical orientations both in static and rotating configurations simulate aspects of simulated-microgravity and influence metabolic responses; this combined analysis provided a broad perspective on gravity-related metabolic adaptations and points to potential molecular markers that could guide future research on spaceflight health and countermeasure development.

plant biology↗
bioRxiv2025

A Multi-lensed Comparative Analysis of Select Secondary Metabolites Produced by Kale, Brassica oleracea, in Simulated Microgravity Versus Gravity Conditions

Extended journeys through space are a goal of NASA. Yet, astronauts will face elevated health risks from microgravity and radiation as journeys continue for longer time periods. Approaches to combatting these health risks consist of growing fresh super foods in space for astronaut consumption while in flight. However, while a great deal is known about the effects of microgravity of humans, little is known about its effects on the nutrient profiles of plants. Endeavors towards understanding more about these effects are currently funded by NASA grants. Kale, a metabolite and specifically a flavonoid-rich crop, stands as a promising candidate for growth on space flights. We observed the effects of simulated microgravity broadly on the F1 cultivar, Starbor Kale metabolomics, and further focused on flavonoid content, using a 2-D clinostat. Extracts of kale were analyzed by proton nuclear magnetic resonance (1H NMR), and high-performance thin layer chromatography (HPTLC). 1H NMR spectra of clinostat-grown kale showed that samples from simulated microgravity conditions had an increased number of peaks in the aromatic region (6.5 to 8.5 ppm) when compared with gravity grown kale. HPTLC confirmed greater banding in medium- and high-polarity solvent systems, while low-polarity extracts showed no differences. Overall, we noted that the microgravity grown kale had greater amounts of bands present. These results signal that microgravity stressors may be connected to the increased secondary metabolite production in kale. Our findings underscore kale to be a prospective crop to be grown in space flight to combat effects of microgravity.

plant biology↗
bioRxiv2022

Virtually the same? Evaluating the effectiveness of remote undergraduate research experiences

In-person undergraduate research experiences (UREs) promote students integration into careers in life science research. In 2020, the COVID-19 pandemic prompted institutions hosting summer URE programs to offer them remotely, raising questions about whether undergraduates who participate in remote research can experience scientific integration. To address this, we investigated indicators of scientific integration for students who participated in remote life science URE programs in summer 2020. We found that these students experienced gains in their scientific self-efficacy and scientific identity similar to results reported for in-person UREs. We also found that these students perceived high benefits and low costs of doing research at the outset of their programs, and their perceptions did not change despite the remote circumstances. Yet, their perceptions differed by program, indicating that programs differentially affected students perceptions of the costs of doing research. Finally, we observed that students with prior research experience made greater gains in self-efficacy and identity, as well as in their perceptions of the alignment of their values with those of the scientific community, in comparison to students with no prior research experience. This finding suggests that additional programming may be needed for undergraduates with no prior experience to benefit from remote research.

scientific communication and education↗
bioRxiv2021

"How do we do this at a distance?!" A descriptive study of remote undergraduate research programs during COVID-19

The COVID-19 pandemic shut down undergraduate research programs across the U.S. Twenty-three sites offered remote undergraduate research programs in the life sciences during summer 2020. Given the unprecedented offering of remote research experiences, we carried out a study to describe and evaluate these programs. Using structured templates, we documented how programs were designed and implemented, including who participated. Through focus groups and surveys, we identified programmatic strengths and shortcomings as well as recommendations for improvements from the perspectives of participating students. Strengths included the quality of mentorship, opportunities for learning and professional development, and development of a sense of community. Weaknesses included limited cohort building, challenges with insufficient structure, and issues with technology. Although all programs had one or more activities related to diversity, equity, inclusion, and justice, these topics were largely absent from student reports even though programs coincided with a peak in national consciousness about racial inequities and structural racism. Our results provide evidence for designing remote REUs that are experienced favorably by students. Our results also indicate that remote REUs are sufficiently positive to further investigate their affordances and constraints, including the potential to scale up offerings, with minimal concern about disenfranchising students.

scientific communication and education↗