Bottlebrush

Other Names : Callistemon viminalis, Callistemon viminalis, Melaleuca viminalis, Red bottlebrush, Metrosideros viminalis, Weeping bottlebrush
Bottle brush is a shrub to a small tree, growing to a height of 5 meters, with numerous, long, slender and drooping branches. Leaves are light green, narrow lanceolate, up to 5 centimeters long. Spikes are 7- 8 centimeters long. Flowers are bright red in dense cylindrical spikes.

• Considered antibacterial, antifungal, anthelminthic, hemostatic, diuretic.
• Studies have shown anthelmintic, anti-quorum sensing, insecticidal, anti-infective, antibacterial, molluscicidal, antioxidant, anticancer, anti-inflammatory, anti-platelet aggregation properties.
• Anti-quorum sensing: Bacterial intercellular communication or quorum sensing (QS) is believed to control the pathogenesis of many bacterial organisms. C. viminalis is one of several plants studied that showed to possess anti-QS activity, a potential new direction for the treatment of bacterial infections. Extracts of plants, including C viminalis, caused the inhibition of QS genes and QS-controlled factors with marginal effects on bacterial growth, suggesting the quorum-quenching mechanisms are unrelated to static or cidal effects.
• Anthelmintic activity: In veterinary studies: The anthelmintic activity of the essential oils of Callistemon viminalis against earthworms and tapeworms has revealed it to exhibit in vitro efficacy better than piperazine phosphate. The activity of these oils against hookworms was comparable to that of hexyle resorcinol (Garg & Kasera, 1982).
• Insecticidal: Study yielded two novel epimeric compounds, viminadione A and viminadione B, Viminadione A exhibited moderate insecticidal activity.
• Anti-infective: One of three plants screened for inhibition of opportunistic human pathogen Pseudomonas aeruginosa that showed reduction in toxin production and mortality and suggests a potential for anti-infective development. (6)
• Chemical Composition / Antibacterial: Study on chemical composition and antibacterial activity yielded 12 components from the leaves of CV. The major components were 1,8-cineole and a-pinene. The oils exhibited inhibition against S faecalis, S aureus, B cereus, S marcesens.
• Antioxidant / Hemolytic Effect / Essential Oil / Leaves: Study investigated the antioxidant potential and oil composition of leaves. A n-hexane extract yielded 40 compounds, with appreciable levels of total phenolic contents (0.27-0.85 GAE mg/g) and total flavonoid contents (2.25-7.96 CE mg/g). A methanolic extract exhibited higher TPC and TFC and scavenging power on DPPH assay. Hemolytic effect of the leaves was found in the range of 1.79-4.95%. (see constituents above)
• Antibacterial / Leaves: Study evaluated water and alcoholic extracts of leaves of C. viminalis in vitro against ten pathogenic bacteria. Results showed antibacterial activity against both Gram positive (Staphylococcus aureus, S. epidermis, Streptococcus pneumonia) and Gram negative bacteria (Klebsiella pneumonia, K. oxytaci, Proteus vulgaris, Escherichia coli).
• Essential Oil from Leaves / Antibacterial / Antioxidant: Study evaluated leaves for antibacterial and antioxidant activities. Essential oil of leaves yielded 14 compounds. Leaf essential oil exhibited the highest antioxidant activity comparable to gallic acid as standard. Essential oil also showed the highest zone of bacterial inhibition compared to standard tetracycline. Crude methanol extract and EA fraction showed significant antibacterial activity. (see constituents above)
• Antimicrobial: Various extracts were tested against eight common bacteria and one fungus. All plant extracts sowed antimicrobial activities against the selected microorganisms; the methanol extract was most effective. The aqueous extract was effective as bactericidal agent against intestinal pathogens.
• Molluscicidal: Methanol extracts of C. viminalis bark and leaves were tested for molluscicidal activity against the vector of schistosomiasis, B. alexandrina snails. C. viminalis fruit extract showed the highest effect against the tested snails. The site of action of all tested extracts was localized in the digestive system and hermaphrodite gland.
• Betulinic Acid / Anti-Platelet Aggregation: Betulinic acid isolated from Callistemon viminalis in combination with oleanolic acid from Syzygium aromaticum showed significant platelet inhibitory activity on epinephrine-induced platelet aggregation.
• Molluscicidal Activity / Fruit, Bark and Leaves: Study evaluated methanol extracts of C. viminalis fruits, bark and leaves for molluscicidal activity. Fruits, bark, and leaves showed LC50 of 6.2, 32, and 40 ppm, respectively. Fruit extract showed the highest effect against the tested snails. (16)
• Anti-Drepanocytosic Activity / Anti-Sickling: In a study of various plants for anti-drepanocytosic, ethyl acetate crude extracts of C. viminalis showed high antisickling activity. The anti-sickling activity of studied extracts was attributed to betulinic acid, betulinic acid acetate, oleanolic acid, and maslinic acid.
• Antioxidant / Anticancer Activity / Leaves: Study identified antioxidant and anticancer compounds in C. viminalis leaf extracts and its anticancer activity against liver cancer cell lines by inhibiting STAT3 protein.
• Silver Dimer Nanoparticles / Antibacterial: Study reports on the use of aqueous extract of C. viminalis leaves as bioreductant for the synthesis of silver nanoparticles. The antibacterial activity of extract reduced nanoparticles showed antibacterial activity against four strains viz. E. coli, S. aureus, K. pneumonia and S. typhimurium.
• Callistemenonone A / Antimicrobial / Leaves: Study isolated a new acyphloroglucinol including an unprecedented dearomatic dibenzofuran core, callistemenonone A, from the leaves of C. viminalis. The potent exerted potent bactericidal activity against a panel of methicillin resistance pathogenic microbes.
• Anti-Inflammatory / Anticancer / DOR and FT Inhibitors: DOR (delta-opioid receptors) and FT (farnesyl transferase) inhibitors can obstruct various intracellular pathways affecting inflammation and cell proliferation. Study reports on the in-silico studies of anti-inflammatory and anti-cancerous properties of C. viminalis derived natural compounds viz. α-terpineol, catechin, methyl gallate and ellagic acid. These compounds have shown excellent binding energy and inhibitory constant for DOR and FT.
• Inhibitory Effect on Non-Small Cell Lung Adenocarcinoma / Leaves: Study evaluated the inhibitory effect of C. viminalis crude leaf extract against A549 non-small cell lung adenocarcinoma. All concentrations of the leaf extract inhibited A549 non-small cell lung adenoCA with an IC50 of 23.21 µg/ml with percent inhibition proportional to extract concentration.
• Bunsenite NiO Nanoparticles: Study reports on P-type Bunsenite NiO powders produced via biosynthesis and heat treatment using aqueous extracts from red flowers of C. viminalis. Results suggest a cost effective and environmentally friendly alternative to preparing Nickel oxide nanosized powders with potential for a variety of energy storage applications.
• NiO Nanoparticles / Pseudocapacitor Applications / Flowers: Study reports on a cost-effective and environmentally friendly method of Nickel oxide nanoparticles synthesis using aqueous extracts of flowers from Callistemon viminalis, with potential for a variety of energy storage applications.
• Larvicidal / Repellent / Essential Oil from Leaves: Study evaluated the insecticidal, larvicidal and repellent activity of essential oils from Callistemon viminalis, M. leucadendron, and H. suaveolenss against Chrysodeixis chalcitesss and compared it to neem oil. The essential oil from leaves showed higher biological activity than neem with 100% larval mortality at 2 µg/ml for 6 h.