This page respects the original work's rights terms and independently introduces its bibliography, abstract, main results, and limitations. It is not a full translation.
About this resource
This is a detailed introduction to a 2015 paper that orally administered a methanol extract of Tabernaemontana sananho leaves to rats and measured responses in 2 animal models related to inflammation and nociceptive stimuli. The research also isolated 2 candidate alkaloids from the same leaf extract and proposed structures from spectral information.
The study material was not sananga eye drops. It was concentrated after extracting dried leaves with an organic solvent and was administered through the rats’ mouths. Every relevant feature—the plant part, extraction solvent, route, and tissue assessed—differed from an aqueous root- or bark-derived liquid for the eye. This was not a clinical trial in humans and is not evidence of human clinical efficacy for sananga eye drops.
Study design
Leaves were collected in July 2009 in Gangakhed, Parbhani district, Maharashtra, India, and reportedly identified and authenticated by the Department of Botany at Bangalore University. Dried leaf powder was macerated first with petroleum ether and then methanol. Acid-base processing, chloroform extraction, and a silica-gel column separated alkaloid fractions. Structures of isolates TS1 and TS2 were examined using mass spectrometry, infrared, and NMR data.
Animal experiments used male and female albino rats and were reported as approved by an institutional ethics committee. In the formalin-induced paw-licking test, there were 4 groups of 6 animals each. Saline, indomethacin 10 mg/kg, and methanol leaf extract at 150 mg/kg or 300 mg/kg were compared. Paw flinches were repeatedly observed for 60 minutes after formalin injection.
The carrageenan-induced paw-edema test used 5 groups of 6 animals each: normal control, carrageenan control, diclofenac sodium 10 mg/kg, extract 150 mg/kg, and extract 300 mg/kg. Paw volume was measured at multiple times. Results were reported as mean ± standard error and analyzed using 1-way analysis of variance and Dunnett’s test.
Content
The formalin test counts rat behavior associated with an acute phase and a later inflammatory response. The carrageenan test measures changes in the volume of experimentally induced paw edema. Both are models for exploring the basic pharmacology of a candidate extract; neither directly measures human pain, ocular inflammation, infection, or visual function.
Chemical separation yielded 10 fractions and purified 2 compounds. The authors proposed TS1 as an ervatamine subtype and TS2 as a new compound belonging to the monoterpene indole alkaloids. Spectral tables in the paper support those structural proposals, but the study did not include subsequent confirmation through independent total synthesis, crystal structure, or reanalysis.
Results
In the formalin test, tables showed fewer flinches in the extract groups at 150 mg/kg and 300 mg/kg than in controls. The authors reported statistical differences across multiple phases and interpreted the findings as dose-dependent antinociceptive and anti-inflammatory activity. In the carrageenan test, extract groups also showed paw-edema values in the direction of reduction relative to carrageenan controls, with a larger change reported at 300 mg/kg.
Chemical analysis yielded TS1 and TS2, for which the authors presented molecular formulae and spectral findings. Their conclusion was that the methanol leaf extract showed activity in animal models and that 2 alkaloids had been isolated.
Some p-value symbols and group labels in the tables are difficult to interpret, and the abstract’s strong conclusion cannot be extended directly to clinical effects. The reported statistical differences were differences in behavior and paw volume among small groups of rats under specific conditions. They do not mean that sananga eye drops improved symptoms in people.
Limitations
Each group contained 6 animals, and details of random allocation, assessor blinding, and sample-size planning are unclear from the text. Both sexes were included, but results were not presented separately by sex. There was no replication experiment, independent-laboratory reproduction, broad dose–response study, or chronic toxicity assessment. Inconsistencies in notation and statistical annotations and the absence of raw data limit precise evaluation of effect size and reproducibility.
The research material was a methanol leaf extract and cannot be generalized to an aqueous liquid from roots or bark or a marketed eye product. Systemic responses to oral administration also cannot be extrapolated to local exposure of the ocular surface. Animal models do not establish treatment effects for human disease, and the study included no human participants, clinical diagnosis, control eye drops, visual-function measures, or safety follow-up.
Safety
The paper was not designed to provide a detailed toxicity profile and did not assess ocular toxicity, corneal epithelium, intraocular pressure, infection, or vision. Findings after oral administration to rats do not predict irritation or injury from applying liquid to the eye. No human safety range was shown for the isolated alkaloids.
Methanol, chloroform, acid-base processing, and column purification were laboratory extraction and identification procedures, not instructions for use. This resource recommends no preparation, dose, or administration method. Basic animal research cannot be used as evidence for self-administration or treatment.
Source and rights
Original source: Rohini RM, Mahesh D. Evaluation of anti-inflammatory and antinociceptive activity and isolation of two new alkaloids from leaves extract of Tabernaemontana sananho. Journal of Chemical and Pharmaceutical Research. 2015;7(1):31–36. No DOI was identified on the article page or PDF.
The publisher provides the full text, but no article-specific Creative Commons statement was identified in the 2015 PDF, and current site policy was not assumed to apply retrospectively. This page independently summarizes the methods, tables, and conclusions without reproducing a full translation, tables, chemical-structure figures, or spectra.