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Higher floral and faunal biodiversity is expected in multi-species-covered mountainous forests than in mono-typic agricultural plantations. To verify this supposition for cryptogamic species like the plasmodial slime molds, a rapid field survey was conducted for myxomycetes and substrates in forest floor litter and agricultural plantation were collected in Negros Occidental, Philippines. Morphological characterization identified a total of 28 species belonging to the genera Arcyria, Ceratiomyxa, Collaria, Comatricha, Craterium, Cribraria, Diderma, Didymium, Hemitrichia, Lamproderma, Physarum, Stemonitis, Trichia and Tubifera. The myxomycete species Arcyria cinerea was the only abundant species found both in the agricultural and forested areas. The majority of collected species were rarely occurring. In terms of species composition, more myxomycetes were recorded in the mountainous forest (27) compared to agricultural sites. Furthermore, aerial leaf litter collected in the forests had the highest number of records for fruiting bodies but in terms of species diversity, twigs yielded higher value based on Shannon index. Findings in this study verify that a habitat with more heterogenous plant communities yields higher species of myxomycete assemblages. This research is the first study to report myxomycetes from Negros Occidental.

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The use of graphical illustration in lecture presentations can make a seemingly boring lesson more attractive and enticing to students. Creating science-themed illustrations and science-based narratives can also lead to creative and critical thinking among students. We used writing editorials and creating editorial cartoons as a learning activity to promote critical thinking and creative skills that are essential in communicating scientific information. This activity can be used with a range of audiences, at various educational levels and in basic to advanced courses.

Purple nonsulfur bacteria (PNSB) are phenotypically diverse group of microorganisms and are known for their biological nitrogen fixation in flooded rice paddies. Our research study, then, aimed to isolate and characterize PNSB and determine their population count. Rice paddy soil samples were collected from San Jose del Monte, Bulacan, and were inoculated into completely filled culture vials pre-filled with different enrichment media, e.g. Larsen's medium, Van Niel's medium, and Acetate Yeast Extract (AYE) medium. Following incubation for 4 weeks under an incandescent bulb, only the AYE medium resulted to bright "red bloom" indicating growth of PNSB. Morphological and cultural characterization of the isolated PNSB showed pinpoint, red colonies and Gram negative, non-spore forming, thin, elongated (0.5 x 2.0 µm) rods. In vivo absorption spectrum using spectrophotometer showed the presence of bacteriochlorophyll a and carotenoids. The isolated PNSB utilized pyruvate, malate, glucose, lactate, citrate and soluble starch as its carbon sources, and ammonium sulfate, peptone and yeast extract as nitrogen sources. Preliminary identification identified the PNSB isolates as Rhodopseudomonas sp. MPN estimated low number of PNSB (2 cells per ml) in the collected rice paddy soil.

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Canarium ovatum Engl. (Pili), a locally grown plant in the Philippines, bears highly pigmented fruits. In this research study, the deeply pigmented fruit exocarp was evaluated for phytochemical contents, functional properties and possible application to yogurt as a colorant. Spectrophotometric analysis of the extract revealed high phenolic and flavonoid content, particularly anthocyanins (17.5 mg CE/g DW of the sample). The pigment extract also exhibited potential antioxidant activities as determined by DPPH and FRAP assays and did not show any inhibitory activity against gut normal flora, Escherichia coli, but also failed to express cytotoxic activity against HCT116 colon cancer cell line. Stability tests showed decreased redness with increasing temperature or pH. The pigment exhibited excellent color retention in yogurt during the two-week storage at 4 o C. Sensory evaluation showed a slight difference in over-all acceptability between natural and synthetic-colored yogurt. Thus, Pili exocarp extract can be used as a functional food colorant in yogurt.

Endophytic fungi as biological control agents pose a novel and promising alternative for plant disease management. Thus, our research study aimed to test whether locally isolated banana root endophytes (BRE) can be used as potential biocontrol agents against Fusarium oxysporum (Foc). Seventy-five BREs were isolated from roots samples of banana cultivars collected from different sites in Manila and Quezon City. High species richness was observed from the plants collected in Quezon City. Twenty-five selected isolates were screened for their antagonistic interactions against F. oxysporum using the dual-culture method, but only three of them inhibited the test fungus either on contact (BRE 18 & BRE 71) or at a distance (BRE 14). Morphocultural characterization identified them as belonging to the genus Aspergillus. Further antagonistic testing showed that the three BREs significantly reduced the colony radial growth of F. oxysporum, particularly when the BREs were grown 15 days prior to Foc inoculation. Extraction of secondary metabolites was done to test the antifungal properties of the three BREs. The crude culture extracts failed to inhibit the fungus using the paper disk diffusion assay, though they were able to remarkably decrease spore germination. Thus, the isolated banana root endophytes showed potential application for biological control.