16 



[January, 1912. 



DRUGS AND MEDICINAL PLANTS. 



NOTE ON THE BEST SEASON FOR 

 COLLECTING MYROB ALANS AS 

 TANNING MATERIAL. 



By Mr. Puran Singh, p.c.s., 

 Chemist to the Forest Research 

 Institute. 



(From the Indian Forester, Vol. 

 XXXVII., No. 10, October, 1911.) 

 It was proposed to examine the fruits 

 of Terminalia Chebula collected at 

 different seasons from the same locality 

 to determine the best time of year for 

 collecting them so as to obtain the 

 greatest yield of tannin. The Forest 

 Chemist received the following speci- 

 mens from the Deputv Conservator of 

 Forests, South Thana. Bombay, collected 

 in different seasons of the year and at 

 different stages of their growth : — 



No. Description. 



1 Half ripe Myrobalans 



2 Nearly ripe Myrobalans 



3 Quite ripe do. 



Date of Collection. 

 . . 27th October, 1911). 

 do. 

 do. 



No. Description. Date of Collection. 



4 Half ripe Myrobalans .. 1st January, 1311. 



5 Nearly ripe do. . . do. 



6 Perfectly ripe do. ... do. 



7 Half ripe do. .. 6th March, 1911. 



8 Quite npe do. . . do. 



9 Quite ripe and dried Myrobalans do. 



The first three specimens were not 

 very different in appearance and size, 

 and of the others, the half ripe and 

 nearly ripe specimens were nearly alike, 

 while the ripe ones were larger in size 

 and deeper in colour. 



These nine specimens, after having 

 extracted and rejected the kernels which 

 contain no tannin, were reduced to a 

 fine powder and were analysed under 

 similar conditions. The results obtained 

 are given in the table below. 



The tannin was estimated by the 

 Nickel Hydroxide process proposed for 

 the first time by- the Forest Chemist. It 

 consists in the use of freshly-prepared 

 Nickel Hydroxide (washed free of alkali 

 and sulphate), in place of chromed hide 

 powder. (See the writer's Note on the 

 use of Nickel Hydroxide in Tannin 

 Estimation.) 



No. of I 

 Sample. | 



Description of Specimen. 



Date of 

 Collection. 



Proportion 

 of Pulp to 

 Kernel 



Moisture. 



Ash. 



1 



Total Solu- 

 ble Solids. 



Tannin es- 

 timated by 

 Nickel Hy- 

 droxide. 1 



. S3 



° 9 



^ as 

 -p 



1 



Half ripe Myrobalans 



27-10-10 



1-5: 1 



9-12 



3 -59 



62-08 



43 96 • 



18-10 



4 



Ditto ... 



1-1-11 



1-88: 1 



8-59 



3-92 



66-64 



49-84 



16-8 



7 



Ditto ... 



6-3-11 



2: 1 



9-26 



3 48 



67-16 



52 96 



142 



o 



Nearly ripe Myrobalans 



27-10-10 



1-53: 1 



9 06 



3-60 



60'00 



41 60 



18-4 



5 



Ditto ... 



1-1-11 



1-89: 1 



8-59 



4-11 



63-00 



46'5 



18-5 



8 



Quite ripe Myrobalans 



6-3-11 



2: 1 



9-00 



3-46 



65-88 



49 88 



16-0 



3 



Ditto ... 



27-10-10 



1-67: 1 



9-61 



3 43 



63-96 



48 01 



15-95 



6 



Perfectly ripe Myrobalans ... 



1-1-11 



2: 1 



9-31 



3-84 



6314 



50-39 



13-55 



9 



Quite ripe and dried Myro- 



















balans... 



6-3-11 



2:1 



8'75 



3-61 



66 88 



51-68 



15-20 



From the foregoing table it will be 

 seen that the ash in all the samples is 

 nearly the same, beiug a trifle more 

 on the unripe fruits. In fully ripe fruits 

 collected in November, January and 

 March respectively, the proportion of 

 pulp to kernel increases from 1'67 to 2 : 1, 

 while in half ripe fruits it increases 

 from 1*5 : 1 to 2 : 1 for the same period, 

 and in the so-called ripe fruits, it also 

 increases from 1*53 : 1 to 2 : 1. 



As for the tannin value, it ranges 

 between 44 per cent, to 53 per cent, from 

 October to March in half ripe fruits and 

 between 42 per cent, to 50 per cent, in 

 nearly ripe fruits, and between 48 per 

 cent, to 52 per cent, in ripe fruits, From 



these results the writer is of opinion that 

 the longer the fruit is allowed to remain 

 on the tree, the higher is its tannin 

 value, and it may be safely recommend- 

 ed that myrobalans should be collected 

 when they are perfectly ripe. 



Trotman in his Leather Trades Chemis- 

 try mentions that there are five chief 

 varieties of chebulic myrobalans named 

 after the district from which they come, 

 and that their price and value vary 

 considerably. It is very difficult, if not 

 impossible, to tell by inspection which 

 are the richest in tannin- Parker and 

 Blochley (Collegium, 1904, 101) have 

 shown that often the haud-picked 

 varieties which fetch a higher price on 



