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The Rafflesiaceae family consists of three genera of parasitic plants -- Rafflesia, Rhizanthes, and Sapria -- with purported ethnobotanical and ethnomedicinal properties. In this study, the inhibitory properties of 21 characterized metabolites associated with Rafflesia and Sapria were tested against eight proteins linked to human diseases -- including seven pathogenic-associated HMGCR, VEGFR2, acetylcholinesterase, NMT, H1N1 neuraminidase, GSK3-β, and estrogen receptor α, and one plant-pathogenic associated Colletotrichum chitin deacetylase. Each metabolite was tested using drug-likeness screening, screening metabolite activity, and molecular docking to eight diseases and microbial physiological processes. Hydrogen bonds and hydrophobic interactions between metabolite ligands and protein residues were characterized. Molecular dynamics were also assessed to analyze the stability of the protein-ligand interaction. Our results indicate that the gallotannins and flavonol phenolics from Rafflesia and Sapria display high inhibitory potential against disease proteins. All metabolite-protein pairs displayed stable fluctuations. However, some compounds disobeyed LRO5 drug-likeness and displayed moderate bioavailability and synthetic accessibility, so an improved drug delivery method is required. All 21 metabolites are available in other popular edible plants (mainly tea and certain berries) and could be used to create artificially mixed metabolite-based medicine to prevent the exploitation and endangerment of wild Rafflesia and Sapria populations. Our activity likelihood screening and molecular docking data indicate that Rafflesia and Sapria metabolites possess considerable potential as anti-cholesterol, respiratory antiviral, wound-healing, and antifungal properties. To protect Rafflesiaceae plants in the wild, metabolites can be assessed from other plant sources and combined as an artificial herbal mix. [ABSTRACT FROM AUTHOR]

This study is the first report on the distribution of Rhipsalis baccifera (J.S.Muell) Stearn in Bandung, West Java, Indonesia. R. baccifera is an epiphyte cactus that generally grows on the vertical substrate of tree barks. The distribution of R. baccifera was examined by tagging the tree hosts using a global positioning system (GPS). Additionally, the organs and growth stages of the cactus, as well as the interactions of the cactus with the host plants, were photographed. The results show that R. baccifera is distributed unevenly in Bandung, as the population density is higher in the northern area of the city than in the south. This uneven distribution suggests that frugivorous birds and human activities in the area play an important role in the distribution of R. baccifera. The cactus has spines during its early stage, which is greatly reduced upon reaching its mature stage. However, within the same region, the cactus appears to selectively grow on specific hosts, mainly on trees with rough barks or grown by moss. In Bandung, the cactus is mostly found growing on mahogany trees (Swietenia macrophylla King). Not all trees adjacent to the host trees have the cactus growing on them, which further suggests the cactus' preference for specific host trees. [ABSTRACT FROM AUTHOR]

Tetrastigma (Vitaceae) are a genus of tropical lianas that are hosts for parasitic plants in the family Rafflesiaceae. Since the stem of Tetrastigma is creeping and often devoid of leaves, it is often mistakenly visually identified as a root. Rafflesia flowers at the ground level (i.e. terrestrial flowers) have been documented to grow on Tetrastigma roots, but it is unclear whether those that arise aerially emerge from host root or stem organs. In this study, we present a new, less-destructive means of sampling Tetrastigma leucostaphylum, which is a host of many Rafflesia species. Histological observation of two 250 cm above-ground aerial samples confirmed that both were stems, as shown by distinct anatomical features (compactly arranged vascular bundles with simple phloem bundles) in contrast to roots, which had loosely arranged vascular bundles with ramified phloem bundles. Clearer identification of Tetrastigma vine infected with aerial Rafflesia is needed to confirm whether the parasitic flower grows on a stem or on an erect aerial root to better understand the biology of this enigmatic Rafflesia species that have evaded cultivation and ex situ conservation efforts. This new sampling method may be a useful way to identify the Tetrastigma vine in the future due to its less invasive nature compared to severing the whole vine. [ABSTRACT FROM AUTHOR]