COMBINATION POTENTIAL SOAKING TEAK LEAVES (Tectona Grandis) WITH HCl ON STAINING GRAM IN Escherichia coli BACTERIA

Safranin or fuchin is a dye that is widely used in the fields of industry, textiles,
histology, cytology and bacteriology. Safranin has a very expensive price in 2019 reaching
3,565,000 / 25 grams. Thus, it is necessary to substitute dyes from natural and much cheaper
materials. Teak leaves (Tectona grandis), especially the young ones, contain the pigment
pheophitin, ß-carotene, chlorophyll and two other pigments that have not been identified as
well as several anthocyanin derivatives, namely, pelargonidin 3-glucoside, pelargonidin 3,7-
diglucoside. Anthocyanins contained in teak leaf (Tectona grandis) buds are reddish brown.
The presence of these pigments can be used in laboratory tests for staining bacteria. The
purpose of this study was to determine the soaking variation of teak leaf (Tectona grandis)
buds for 24 hours, 48 hours, 72 hours, 96 hours in 96% alcohol with concentrated HCl, and
the use of safranin as a positive control. The data of the research was in the form of scores of
observations. Based on the Kursal Wallis alpha test, it was found that there was a significant
difference in the results of staining bacteria among various soaking of teak leaf (Tectona
grandis) buds in 96% alcohol with concentrated HCl in staining gram technique. Soaking
teak leaf (Tectona grandis) buds in 96% alcohol with HCl for 72 hours and 96 hours gave the
same staining results as safranin. The results showed that soaking teak leaf (Tectona grandis)
buds in alcohol with concentrated HCl can be used as an alternative natural dye for the
method of staining Gram on Escherichia coli bacteria.