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 Table of Contents  
ORIGINAL ARTICLE
Year : 2018  |  Volume : 12  |  Issue : 3  |  Page : 125-131

Physicochemical study of the homoeopathic drug, Blatta orientalis


1 Drug Standardisation Unit, Hyderabad, Telangana, India
2 Central Council for Research in Homoeopathy, New Delhi, India

Date of Submission07-Apr-2018
Date of Acceptance11-Sep-2018
Date of Web Publication27-Sep-2018

Correspondence Address:
Dr. Bibaswan Biswas
Drug Standardisation Unit [H], O.U.B-32, Vikrampuri, Road No. 4, Habsiguda, Hyderabad - 500 007, Telangana
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijrh.ijrh_24_18

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  Abstract 


Introduction: Blatta orientalis or oriental cockroach, also known as water bug or black beetle, belongs to class insecta and family Blattidae. In Homoeopathy, medicine prepared from it is used in a number of ailments, especially in the treatment of asthma. Materials and Methods: The physicochemical study includes evaluation of different parameters, namely foreign matter, moisture content, total ash, water-soluble and acid-insoluble ash values, water and ethanol extracts of the raw drug. Physicochemical studies, namely organoleptic specifications, sediment, specific gravity determination, total solids, pH measurement, thin-layer chromatography (TLC), ultraviolet-visible spectra and alcohol content have also standardised and presented for both in-house and commercial mother tinctures (finished products). Results: The study indicates that the values of the preliminary parameters of this drug are quite different from the ranges reported for plant drugs. TLC study confirms the complexity of the composition of the prepared drug. Conclusion: The physicochemical data of the drug, B. orientalis, may serve as pharmacopoeial standard for authentication, quality assurance and quality control process of the commercially available drug.

Keywords: Asthma, Blatta orientalis, Homoeopathy, Physicochemical


How to cite this article:
Biswas B, Jhansi S, Potu R, Patel S, Nagaraju M, Arya R, Sundaram E N, Khurana A K, Manchanda RK. Physicochemical study of the homoeopathic drug, Blatta orientalis. Indian J Res Homoeopathy 2018;12:125-31

How to cite this URL:
Biswas B, Jhansi S, Potu R, Patel S, Nagaraju M, Arya R, Sundaram E N, Khurana A K, Manchanda RK. Physicochemical study of the homoeopathic drug, Blatta orientalis. Indian J Res Homoeopathy [serial online] 2018 [cited 2018 Nov 21];12:125-31. Available from: http://www.ijrh.org/text.asp?2018/12/3/125/242277




  Introduction Top


It is beyond any debate that nature is the single most important source of bioactive compounds as almost all organic medicines presently available are either originated or inspired from natural products.[1],[2],[3],[4],[5],[6],[7],[8],[9],[10],[11],[12],[13],[14],[15] Among natural products, medicinal plants have caught great attention from drug discovery community.[16],[17],[18],[19] However, several medicines which are derived from animals in general or their secretions or products, such as different kinds of worms, lice, insects, beetles, flies, crabs, toads and snakes are also used in Homoeopathy for various ailments.[20],[21],[22],[23],[24],[25],[26] Homoeopathy rightly recognised the potential of animal kingdom for medicinal purpose from its origin and among them, Blatta orientalis is quite distinctive.[27],[28] The medicinal activity of B. orientalis was accidently discovered when B. orientalis-contaminated food (tea) relieved a patient from asthma by considering the 'Law of Similars'. In Homoeopathy, B. orientalis mother tincture and its dilutions are prescribed to treat asthma, bronchitis, cough and dyspnoea.[29]

B. orientalis is regarded as a harmful pest responsible for a number of diseases, including dysentery, food poisoning and diarrhoea.[30],[31],[32],[33],[34] The mother tincture of B. orientalis has been found to possess anti-asthmatic activity against acetylcholine and histamine aerosol-induced bronchospasm in guinea pigs.[35] The mother tincture has also been reported to possess anti-anaphylactic activity against passive as well as anaphylaxis models in rats.[35] Haemolymph of B. orientalis had shownin vitro antibacterial activity against Staphylococcus aureus, Proteus mirabilis,  Salmonella More Details typhi, Pseudomonas aeruginosa and  Escherichia More Details coli.[36] The reported chemical constituents of haemolymph of B. orientalis are triazoles, thiophenes, secondary sulphonamide, vinyl halides, sulphinic acid, secondary amide, bromo compounds, cyclopeptane, aldehyde/ketones group and methylene groups.[36] Considering its medicinal effect as potential anti-asthmatic drug in Homoeopathy, the present study was carried out to standardise the raw drug and homoeopathic formulation (mother tincture) of B. orientalis. The physicochemical data presented in this research article may also be used as pharmacopoeial standard to ensure the quality of commercial samples. This work upgraded already published monograph of B. orientalis at HPI.[37]


  Materials and Methods Top


Collection of B. orientalis

Live B. orientalis was collected from household manholes and corners of buildings by using sterile surgical gloves which were duly identified and authenticated with the help of Department of Zoology, Osmania University, Hyderabad.

Description of Blatta orientalis

Drug was prepared from whole live B. orientalis Linn. (synonym: Blatta lucifuga Poda; Blatta badia Saussure; Blatta castanea Blanchard; Family: Blattidae). B. orientalis is a common cockroach in India, where it inhabits human dwellings and damps moist corners. It is a dictyopteris insect, with an elongated oval rather flat body, from 18 to 30 mm in length, of a red or brown-red colour, which becomes paler under belly. Mouth parts are biting type, mandibles are strong and toothed. The prothorax is smooth, shining, with two large brown spots. In the male, the elytra reach beyond the belly. In the females, they are little shorter. The wings are striate and reticular, of the length of elytra. The antennae are filiform, longer than the body and exhibit at their base is small yellowish point. The feet are provided with black prickles and terminate in tarsus with five articulations and a pair of claws with pulvilus. In B. orientalis, the dorso plunal line of the abdomen is contained in the narrow, unfolded lateral membrane uniting the paratergites and the large ventral plates. In the male cockroach, the ventral plate of the ninth segment bears a pair of the styles. Genital segments of the female are almost entirely concealed within the seventh segment. Anal cerci (a pair) are present in both sexes.

Physicochemical studies

Physicochemical studies, namely foreign matter, moisture content, total ash, water-soluble and acid-insoluble ash values, water and ethanol extracts were done using whole body of B. orientalis in accordance with the procedure described by Homoeopathic Pharmacopoeia of India (HPI). For thin-layer chromatography (TLC), aluminium plates, pre-coated silica gel and fluorescent indicator 60F-254™ of 0.25-mm thickness manufactured by Merck were used. The spots were detected by ultraviolet (UV) lights having wavelengths 366 nm and 254 nm.

Experimental procedures

Loss on drying

Around 2 g of air-dried raw drug was kept in a well-ventilated oven for 3 h at 105°C. After removing the drug from the oven, it was allowed to cool to room temperature by keeping the dried raw drug in a desiccator for 20 min. Then, it was again weighed. The loss on drying (LOD) (moisture content) in percentage was calculated as follows:

  • Weight of emptying the  Petri dish More Details = wempty
  • Weight of the Petri dish with air-dried raw drug = w+wet
  • Weight of the air-dried raw drug = w+wetwempty= wwet
  • Weight of the oven-dried (105°C) raw drug = w+drywempty= wdry
  • % LOD = .


Preparation of mother tincture (φ)

As directed in HPI, the mother tincture was prepared according to the method described at HPI.[37]

Preparation of potencies

The solid potencies (f) were prepared according to HPI.[37]

Extractive values

Around 2.0 g of raw drug was weighed (moisture content was taken into account). To it, 50 mL of EtOH was added and kept for 24 h at room temperature. After filtering it, 10 mL was taken and evaporated on a water bath. Thereafter, it was heated at 105°C in a well-ventilated oven till constant weight was achieved. The above experiment was performed twice and an average value was reported. The ethanol extract value was calculated as follows.

  • Drug weight = wdrug (moisture content was subtracted to calculate the drug weight)
  • Empty beaker weight = wempty
  • Beaker + dried extract weight = w+drug
  • % EtOH extract = .


In a closely related experiment, water extract value was determined using 50 mL of water instead of ethanol.

Ash values

Determination of total ash value

Around 2.0 g of raw drug was weighed (moisture content was taken into account) in a thermally resistant previously weighed crucible. The crucible along with its content is heated to 450°C for 30 min. The crucible was cooled in a dedicator for 15 min and weighed. This procedure was repeated till constant weight is obtained.

Then, the percentage of total ash was calculated with reference to the drug weight.

  • Empty crucible weight = wempty
  • Drug weight = wdrug
  • Crucible + ash weight = w+ash
  • Total ash= w+ashwempty= wash
  • % Total ash = .


The above experiment was performed twice and an average value was reported.

Determination of acid-insoluble ash value

The ash obtained as directed under total ash value was boiled with 25 ml of 10% HCl for 5 min. The insoluble matter was collected on an ash-less filter paper, washed with hot water, ignited for 15 min at a temperature about 450°C. The crucible was cooled in a desiccator for 15 min and weighed. The heating was repeated till a constant weight is reached. The above experiment was performed twice and an average value was reported.

  • Empty crucible weight = wempty
  • Drug weight = wdrug
  • Crucible + acid-insoluble ash weight = w+acid(i)ash
  • Acid-insoluble ash = w+acid(i)ashwempty
  • % acid-insoluble ash = = %w/w.


Determination of water-soluble ash value

The total ash obtained was boiled with 25 ml of water for 5 min. The insoluble matter was collected on an ash-less filter paper, washed with hot water and ignited for 15 min at a temperature about 450°C. The crucible was cooled in a dedicator for 15 min and weighed, repeated for constant value. The weight of insoluble matter was subtracted from the weight of total ash. The difference in weight represents the water-soluble ash. The percentage of water-soluble ash was calculated as follows. The above experiment was performed twice and an average value was reported

  • Empty crucible weight = wempty
  • Drug weight = wdrug
  • Crucible + water-insoluble ash weight = w+water(i)ash
  • Water-insoluble ash = w+water(i)ashwempty
  • Water-soluble ash = Total ash − Water-insoluble ash = washw+water(i)ash= wwater(s)
  • % Water-soluble ash= .


Determination of total solids

A 10 mL of mother tincture of the drug was heated on a water bath to remove the alcohol. After that, the water content was removed by heating it inside a well-ventilated oven. The sample was cooled in a desiccator for 15 min and weighed. The heating process was repeated till constant value is reached. The above experiment was performed twice and an average value was reported.

  • Empty beaker weight = wempty
  • Beaker + dried extract weight = w+drieddrug
  • Total solids= w+dried drugwempty
  • %Total solids=
  • Specifically in this case:
  • %Total solids= .


Weight per mL

10 mL of the mother tincture was weighed and the weight was divided by 10 to get the data.

pH

The pH was determined by a digital pH meter. The pH of the samples (authentic and commercial) was recorded only after calibration using buffer solutions each time.

λmax

The measurement was made by diluting the mother tincture by ~100 times. The diluting solvent is same as the mother tincture solvent system.

High-performance thin-layer chromatography

Around 25 mL of the mother tincture was heated on a water bath to remove alcohol. The residue thus obtained was extracted by three 20 mL portions of chloroform. The chloroform extract was then concentrated to ~2 mL by heating on a water bath. This concentrated extract was used to carry out high-performance TLC (HPTLC) on pre-coated silica gel aluminium plate 60F-254 of 0.25 mm thickness manufactured by Merck, using 9:1 CHCl3:CH3 OH mixture as the solvent system. The spots were detected by UV lights with λmax= 254 nm and 366 nm. Furthermore, the spots were detected under visible (Vis) light via derivatisation using anisaldehyde-sulphuric acid stain.


  Results and Discussion Top


The results of the physicochemical study of the raw drug are summarised in [Table 1]. The LOD was found to be 76.85% which is important to gauge the amount of raw wet drug needed for the mother tincture. Furthermore, the value is quite high compared to the plant-based drug. This is quite expected considering the nature of the raw drug. Besides LOD, the ash values (particularly total ash) are considerably low compared to corresponding plant based drugs. As acid-insoluble and water-soluble ash values do not differ much from the total ash value, it could be argued that the ash value measurements could effectively be used for approximate measurements of the heavy and alkali metals. Considerably high values of the water and ethanol extracts indicated that the raw drug has considerable amount of polar constituents.
Table 1: Raw drug parameters

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In [Table 2] (column 2), the parameters of the authentic finished product (mother tincture) have been given including the organoleptic profile. As the total solid value is considerably high, it is fair to infer that the chosen solvent system for mother tincture preparation is quite effective to extract active pharmaceutical ingredients from the raw drug. The pH of the mother tincture is close to the neutral pH. This measurement indicates that lower potencies are indeed safe for oral administration. The UV-spectra of the mother tincture showed absorptions in far UV region, indicating that highly conjugated or complex metallic complexes could be absent in the finished products. HPTLC study was performed on the chloroform extract of the mother tincture. Interestingly, spot at baseline for pure mother tincture indicates that the drug contains considerable amount of highly polar constituents. Thus, further analytical studies could be undertaken to resolve the spot. Considering the rules set by HPI, the Rf values have been solely calculated for chloroform extract of the mother tincture.
Table 2: Finished product parameters

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Comparative study

The study was further extended towards a comparative study of our in-house, authentic mother tincture with a commercial mother tincture.

The data of the comparative study have been summarised in [Table 2]. The data clearly showed that the characteristics of the commercial mother tincture are quite different from the authentic in-house mother tincture prepared in accordance with the procedure set by HPI. This comparative study is quite important as this study is first of its kind. From the data, it is quite evident that the two samples differ considerably in terms of organoleptic data, which is considered as the most preliminary data related to quality assurance. Even though sediments are absent in both the cases, this parameter solely cannot be used to authenticate. Surprisingly, total solid is quite high in case of commercial sample. This might be due to the inclusion of foreign matters during the preparation of the mother tincture. The lower value of specific gravity could be attributed to the presence of low-density components. Even though pH of the samples seems quite comparable, this is not quite the case as pH = −log10[H+]. Using this equation, the [H+] concentration authentic sample is found to be ~ 1.5 times more than that of the commercial one. The pH value is not only important for safe oral administration but also is important for bioavailability and bioequivalence of orally administrated drugs. UV-Vis measurements showed that the samples have different λmax values. Even though identical UV-Vis measurements could not be directly translated to the authenticity difference in spectra certainly indicated that the samples possess different chemical composition. In order to verify this, we explored a comparison of the chemical composition of the samples by HPTLC [Figure 1]. From the HPTLC plates, it is quite evident that the compositions of the samples are appreciably different. Considering the results, we could infer that the commercial differs substantially from the authentic sample [Figure 2]. However, the origin of this disparity could not be ascertained without further study.
Figure 1: AB: Authentic in-house; BC: Commercial. Left: 254 nm, Middle: 366 nm, anisaldehyde-sulphuric acid stain

Click here to view
Figure 2: Authentic in-house (A) and commercial (C) mother tincture

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  Conclusion Top


This novel study provides the physicochemical standard of the homoeopathic drug B. orientalis. Hence, the measured parameters furnished standards of the drug. These could be used for quality control and quality assurance of the drug, B. orientalis under industrial setup. Besides, the different results of the parameters for the in-house authentic sample and the commercial sample are evidently indicative of the necessity of the study. Overall, this in-depth study generated the physicochemical data of the homoeopathic drug B. orientalis for the first time.

Acknowledgement

The authors are thankful to Prof. H. Ramakrishna and all the supporting staffs of DSU (H), CCRH, Hyderabad, Telangana, India.

Financial support and sponsorship

Nil.

Conflicts of interest

None declared.

 
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    Figures

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    Tables

  [Table 1], [Table 2]



 

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