Journal of Global Resources
Volume 6 (01)August 2019-January 2020
Page 141-147
UGC–CARE Listed Journal in Group D
ISSN: 2395-3160 (Print), 2455-2445 (Online)

22
BIOLOGICAL TREATMENT OF TANNERY EFFLUENT USING CYANOBACTERIA AND
NRK FOR SANSEVIERIA TRIFASCIATA PLANT GROWTH
Mohamed Riyaz. S. 1, Sowmya. R2, Jenifer. G. 3, Ketut Gede Dharma Putra4
Jenny. S. 5 and Malliga. P. 6*
1

Department of Biotechnology,
Pavendar Bharathidasan College of Engineering and Technology, Tiruchirappalli, India
2&3
Department of Marine Biotechnology, Bharathidasan University, Tiruchirappalli, India
4
Centre for Sustainable Development, Udayana University, Bali, Indonesia
5
Assistant Professor, Department of Microbiology, Cauvery College for Women, Tiruchirappalli, India*6
Professor & Head, Department of Marine Biotechnology, Bharathidasan University,
Tiruchirappalli, India *Email: malliga.p@bdu.ac.in

Abstract: The leather industries are regarded as one of the major contributors of industrial
pollution as the effluent discharged is highly putrescible volume and when untreated damages
the normal life of the receiving stream. The present study aims to ameliorate hazards andwaste products into applicable organic manure by the combined treatment of tannery effluent,cyanobacteria, coir pith and Nava Rasa Karaisal (NRK). The genus “Sansevieria” has beenanciently used for various health alignments (inflammation, anti-allergic reactions and antivenom) all over the world especially in China, African countries and tropical America. In recent
years, the people are encountering major health hazards and challenges due to air pollution
and pollutants released from tannery. Thus, this study aims at the plant Sansevieria trifasciata(capable of absorbing toxins from air and releases O2 at night) was grown by using manure
obtained from combined treatment as basal application. The physiochemical, biochemical andSEM analysis were done on 50th day while morphological parameters (shoot length and width,no. of leaves) at indoor and outdoor light intensity were monitored on initial and 50th day. The
obtained results showed reduction in physiochemical and heavy metal contents after combined
treatment of tannery effluent. The morphometric parameter analysis also showed increased
plant growth after combined treatment in indoor plants when compared to outdoor plants.
Key words: Tannery, Lyngbya sp., coir pith, NRK, Sansevieria trifasciata, Growth Study
Introduction
Leather industry is one of the oldest industries in India and one of the leading foreign exchange
earners for the country. But the industry is plagued by heavy pollution stress on theenvironment, thus negating some of the other societal benefits the industry has merited.
Production of leather, leather goods, boards and fur produces numerous by-product, solid
waste, and high amount of wastewater containing different loads of pollutants. Thus, theseindustries are considered to be one of the major contributors of industrial pollution(Alebelabebe, 2010). During the conversion, a series of chemical processes and physicaloperations are carried out to attain the final desired properties of leathers. Pre-tanning, tanningand post-tanning are the major steps involved in leather processing (Ganesh and Ramanujam,2009). Abirami et al. (2013) reported that majority of industry is water based and considerable
volume of waste water is discharged into the environment either untreated or inadequately
treated which leads to the problem of surface and ground water pollution. To overcome thisproblem, some physical and chemical methods, such as reverse osmosis, ion exchange,
membrane filtration and electro dialysis are used effectively for removing but they are
expensive and generating concentrated wastes that require subsequent treatment anddisposal. Biological removal may provide a suitable means for treatment from wastewater(Murali et al., 2013).There has been an increasing concern over dangerous levels of heavy
metals contaminating the environment. Increase in environmental contamination leads to a
progressive deterioration of environmental quality. This condition challenges us to find effective
measures of remediation.
Bioremediation is an eco-friendly and natural technology targeted to eliminate heavy
metals, radionuclide, xenobiotic compounds, organic waste, pesticides etc. from contaminated141sites or industrial discharges through biological means (David and Rajan, 2012) The applicationof cyanobacteria showed immense potential in waste water and industrial effluent treatment,
bioremediation of aquatic, terrestrial habitat, chemical industries, bio fertilizers, food, feed, fueletc. Cyanobacteria also known as blue green algae are ubiquitous in nature and distributed
group of prokaryotic photoautotroph microorganism (Sanjay et al., 2011).They are gramnegative filamentous or unicellular that grows as mats on the surface of bare soil as primarycolonizers. The cyanobacteria Oscillatoria annae grows luxuriantly along with coir pith in field
condition (Anandhraj et al., 2012).
Coir pith is the by-product of coir yarn industries which constitute about 70% husk. As
coir pith has high content of lignin and it takes decades to decompose, it causes environmental
hazards because of its disposal problems (Krishnamoorthy et al., 2012).The recent researchshows that coir pith can be partially decomposed through the action of cyanobacteria and canbe used as biofertilizer for all varieties of food crops (Jenny and Malliga, 2016). Nava Rasa
Karaisal is a concoction prepared by mixing of nine products and used in traditional rituals. It
enriches the soil and provides the entire nutrient required for the growth of the plant.
Physicochemical and biological properties of Nava Rasa Karaisal revealed that they posses
almost all the macro nutrients, micro nutrients and growth hormones required for crop growth.
Nava Rasa Karaisal is a rich source of nitrogen and valuable microorganisms which naturally
enhances soil fertility. The seven species of the genus Sansevieria, monocots in the family
Asparagaceae are popular ornamental evergreen perennials characterized by verticallyelongated rigid leaves arranged in a rosette around a single growing point, with distinct darkcross-banded coloration patterns (Gautham et al., 2012).The Snake Plant, or Mother-in-Law's
Tongue, is one of the most recommended plants for improving air quality (Gargi et al.,2017).The NASA conducted a study to evaluate the uses of snake plant. According to theirresults they found out that the snake plant absorbs toxins, such as nitrogen oxides andformaldehyde. Sansevieria trifasciata is able to absorb 107 types of toxins, including the toxins
generated from air pollution, cigarette smoke (nicotine), which would make a great refresher(Julie et al., 2017).The snake plant (Sansevieria trifasciata) was also evaluated for their species
effectiveness in reducing ozone concentrations in a simulated indoor environment (Heather etal., 2009).
MATERIALS AND METHODS
Effluent Collection
The tannery effluent was collected from a tannery industrial unit situated at Sempattu,
Tiruchirappalli, Tamil Nadu, India.
Lignocellulosic Waste
Coir pith was collected from coir industries near Srirangam, Tiruchirappalli, Tamil Nadu, India.
Organism and Source
Filamentous, non-heterocystous marine cyanobacteria Lyngbya sp. was obtained from the
germplasm collections of National Facility for Marine Cyanobacteria (NFMC), Department ofMarine Biotechnology, Bharathidasan University, Tiruchirappalli, Tamil Nadu, India.
Media and Growth Conditions
The obtained cyanobacteria was cultivated and maintained under laboratory conditions withtemperature of 25±2˚C and light requirement of 1500 lux with light/dark cycle of 14/10 hr.
illuminated with fluorescent tubes, sustained in the respective ASN III medium (Rippka et al.,1979).
Treatment
In this study, water was used as control. For combined treatment, the raw tannery effluent was
inoculated with cyanobacterium and also in combination with coir pith and incubated for 20
days. After incubation, the obtained pellet was treated with Nava Rasa Karaisal and incubatedfor 10 days for further degradation and used as basal manure for plant treatment. The
physiochemical parameters, heavy metal and nutritive factor analysis were carried out on 30th
day of the study period.

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Determination of pH
The pH of the sample was determined using pH meter which has been initially standardized bybuffer solution of known value before analysis.
Determination of COD and BOD
The COD and BOD were measured according to the standard methods (APHA, 1998).
Estimation of Heavy Metals
The heavy metals like Iron, Chromium, Nickel, Cadmium, Lead, Selenium, Arsenic, Fluoride,
Copper, Manganese, Mercury and Zinc were estimated according to the standard methods(AOAC, 2000)
Estimation of Nutritive Factor
The NPK levels were estimated using standard methods; Nitrogen (Jackson et al., 2001),
Potassium (Hald, 1947) and phosphorous (APHA, 1998).
SEM Analysis
The SEM analysis was performed to identify the adherence of particles (size 10µm and 2µm)
on the untreated and treated tannery effluent on 30th day of the study period.
Pot Experiment
The pot experiment was conducted to analyze the growth of the plant Sansevieria trifasciata.
The 1 kg pot was prepared with combination of manure, coir pith and soil in 1: 2: 2 ratio. One
set of plants were kept in outdoor at a light intensity about 15,000 lux and the other set of plants
were kept at indoor light intensity about 500 lux. The plants were washed thrice to remove all
the traces of extra leaf of the plant. The initial and final (50th day study) morphometricparameters (shoot length and width, No. of leaves) were monitored for both set of plants. Thus,
the aim of this study was to investigate the effect of untreated and treated tannery effluent onplant growth and its morphometric parameters.
RESULT AND DISCUSSION
Determination of Physiochemical Parameters
The pH was observed to be mild acidic in nature and on 30th day, the pH of untreated (TN) andtreated tannery effluent (TN+CP+CB+NRK) value showed as 8.87 and 6.56. The BOD and
COD levels were greatly reduced in combined treatment (TN+CP+CB+NRK) on 50th day
analysis when compared with untreated tannery effluent. The BOD levels were 356mg/l (TN),
290mg/l (T.TN) while COD levels were observed to be 1.98 g/l (TN), 1.404 g/l (T.TN)
respectively (Fig.1). The findings were similar to the observations of Anamika et al. (2013)
which showed that the values of BOD and COD of untreated tannery effluent to be 1.2 g/l and2.3 g/l respectively and levels of BOD and COD were reduced after treatment with
Pseudomonas sp. to 0.9 g/l and 0.3 g/l respectively on 20th day. The BOD and COD levels
were recorded as 340 and 610 mg/l respectively with untreated tannery effluent but after
inoculation with Pseudomonas sp. the levels were reduced to 90 and 220 mg/l respectively on
15th day (Srinivas and Estari, 2012).
Figure 01: Effect of Basal Treatment on (a) BOD (b) COD
2500
Values (mg\g\l)

1980
2000
1404

1500
1000
500

356

290

0
BOD
TN – Untreated Tannery
T.TN – Treated Tannery Effluent

COD

Parameters

TN

T.TN (basal)

Estimation of Heavy Metals
The presence of heavy metals like Iron (20.5mg/l), Chromium (84.6mg/l), Lead (10.3mg/l) andNickel (6.7mg/l) were observed in untreated tannery effluent. But after combined treatment(TN+CB+CP+NRK), a reduction in the levels of heavy metals like Iron (14.68mg/kg), Chromium143(2.73mg/kg), Lead (2.2mg/kg) and Nickel (3.72mg/kg) were observed (Fig. 2a). Similarly, thepresence of heavy metals like Mercury (1.20mg/l), Cadmium (10.0mg/l), Copper (25.0mg/l) andZinc(12.4mg/l) in untreated tannery effluent were reduced into Mercury 0.56mg/kg, Cadmium(3.98mg/kg), Copper (0.85mg/kg)
and Zinc (2.22mg/kg) in combined treatment(TN+CB+CP+NRK) (Fig. 2b). The levels of Arsenic (2.8mg/l), Fluoride (12.0mg/l), Manganese(5.6mg/l) and Selenium (5.5mg/l) in untreated tannery effluent were reduced as Arsenic(1.16mg/kg), Fluoride (11.5mg/kg), Manganese (2.85mg/kg) and Selenium (1.84mg/kg) whentreated with the microbial consortium (Fig. 2c).
Sharma and Malaviya (2011) revealed that high level of chromium (9.86 mg/l) waspresent in untreated tannery effluent but after treatment with Fusarium chlamydosporium, thelevel was reduced (0.00 mg/l) respectively on 6th day. Selvi et al. (2012) also reported higher
reduction of Pb (90%), Cu (85%), Zn (80%), Cr (70%) and Hg (80%) from tannery effluent using
isolated strains of Pseudomonas sp. All heavy metals were found to be reduced with all thetreatments notably with the combined treatment of Lyngbya sp. with coir pith in tannery effluent
due to absorption of heavy metal particles on the surface of Lyngbya sp. and coir pith (Lakshmi
et al., 2015)
Figure 02: Effect of Basal Treatment on Heavy Metals
30

84.6

80

Values (mg\kg)

Values (mg\kg)

100

60
40
20

20.5
14.68

10.3
2.25

2.23

6.73.72

20
15

12.4

10

10
5

3.98

0.85

2.22

Cadmium
CopperParameters
TN
T.TN (basal)

Zinc

1.20.56

0

0
Iron

a)

25

25

Chromium

Lead

Parameters
TN
T.TN (basal)b)

15
Vlues (mg\kg)

Mercury

Nickel12 11.5

10
5.6
5

5.5
2.85

2.8
1.16

1.84

0
Arsenic
TNc)

Fluoride

Manganese

Selenium

T.TN (basal) Parameters

TN – Untreated Tannery
T.TN – Treated Tannery Effluent

Estimation of Nutritive Factor
The NPK levels of the untreated tannery effluent showed 18.84mg/l, 290mg/l and 2.25mg/l
respectively. However, these levels were reduced as N (1.5mg/kg), P (5.98g/kg) and K(2.7g/kg) respectively after treatment (Fig. 3). Shurky (2001) reported increase in soluble
nitrogen content in wheat grains when irrigated with industrial effluents. Chhonkar et al. (2000)
reviewed that addition of tannery effluent caused deflocculation of soil particles and increase in
the N, P and K levels of soil.
Figure 03: Effect of Basal Treatment on NPK Levels

Values(mg\kg)

400
290

300
200
100
0

18.84 1.5
Nitrogen

TN – Untreated Tannery
T.TN – Treated Tannery Effluent

5.98

2.25 2.7

Phosphorus

Potassium

Parameters
TN

T.TN (basal)

Scanning Electron Microscopic view of treated tannery effluent (TN+CB+CP+NRK) on
30thday
Scanning Electron Microscope (SEM) is an eminent technique that can be used to investigate
binding of metals to algae (Yan and Pan, 2002). In this study, the SEM was analysed on
untreated and treated tannery effluent with basal application at 10µm (Plate 1a & 1c) and 2µm
144

(Plate 1b & 1d)) particle size on 30th day. The obtained results showed that the treated tannery
effluent showed more smoothened surface modifications at both 10µm and 2µm particle sizes
when compared to untreated tannery effluent. This could be due to the degradation of tannery
and coir pith residue by cyanobacteria and the microbial consortia present in Nava Rasa
Karaisal. SEM micro-graphs showed that, the algal cell before treatment had a normal shapewith smooth and transparent external layer outside cell surface. After treatment, the cell withheavy metal adsorbed become slightly rough and corrugated textures and some particles were
found on the surface of the cell wall (Kayil et al., 2015). Lombardi et al. (2002) described thatcell wall is the first barrier to uptake of metals and that surface adsorption is an importantmechanism of defense that eventually permits microalgae to tolerate high levels of toxic
metals into the surrounding medium. SEM results revealed that most heavy metals wereaccumulated on the cell surface of the microalgae. SEM was performed to analyze themorphological changes (20 μm) of organic manure and this could be due to the degradation oflignin like substances has been enhanced by the activity of microorganisms during incubation
because of increased surface area and aeration.
thPlate 01: SEM Images of Treated Tannery Effluent on 30 day (10 and 2µm particle size)a) TN at 10µmb) TN at 2µmc) T.TN at 10µmd) T.TN at 2 µm

TN – Tannery effluent, CB- Cyanobacteria, CP- Coir Pith, NRK – Nava Rasa Karaisal
TN – Untreated Tannery; T.TN – Treated Tannery Effluent

Pot Experiment and Plant Growth
The pot experiment was conducted to study the Sansevieria trifasciata plant growth at two
different conditions and light intensities (Indoor plants at 500 lux light intensity, Outdoor plants
at 15,000 lux light intensity) with fertilizer obtained from combined treatment as basal
applications. The basal fertilizer was applied to pots as 20g conc./pot and the plant growth wasmonitored on initial and 50th day in terms of morphological parameters such as shoot width,shoot height and no. of leaves of the plant. On initial day, the morphometric parameters likewidth, height and no. of leaves were monitored for both indoor and outdoor plants. The
obtained results showed that there was an increase in the morphometric parameters of theindoor plants when compared to outdoor plants. However, application of basal fertilizer showed
better growth on 50th day (Table 1 & 2).

CN

TTN

Indoor

CN

TTN

CN

Outdoor

TTN

IndoorPlant growth – 0th day

CN

TTN

OutdoorPlant growth - 50th day
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Table 01: Morphometric Parameter Analysis on Initial Day#
1.
2.

Experimental
Condition
OUTDOOR(15,000LUX)INDOOR(500LUX)

Treatment
CN
TTN
CN
TTN

Morphometric parameters
Shoot width(cm)Shoot height(cm)No. of leaves
4.85±0.14
26.57±2.354.88±0.16
27.57±2.354.91±0.13
27±3.254.91±0.11
27.85±2.85Table 02: Morphometric Parameter Analysis on 50th day#
1.
2.

Experimental
condition
OUTDOOR(15,000LUX)INDOOR(500LUX)

Treatment
CN
TTN
CN
TTN

Morphometric parameters
Shoot width (cm)Shoot height (cm) No. of Leaves
5.18±0.16
29±2.355.31±0.16
32.14±2.375.18±0.16
29.5±2.1255.31±0.1332.8±2.42
8
CN-Control; TTN – Treated Tannery Effluent

Conclusion
The adverse effect of tannery waste water is a challenging process for tannery industry and thesurrounding environment. Therefore, to reduce the adverse effect of tannery industry discharge
to the environment, an alternative, cost-effect and eco-friendly methods are a priority
requirement. Thus in this study, the tannery effluent treated with coir pith, Nava Rasa Karaisal(NRK) and Lyngbya sp. (combined treatment) and untreated tannery effluent studied withrespect to physiochemical parameters (BOD and COD) and heavy metals showed reduction in
their levels. The SEM analysis (10µm and 2 µm particle size) also showed surface
modifications and smoothening of the surface after treatment due to the degradation ofparticles present in the effluent by cyanobacteria and microbial population present in NRK. The
morphometric characteristics and plant growth of Sansevieria trifasciata at 20% concentrationas basal fertilizer in indoor pot experiment at 500 lux intensity showed increased plant growth interms of plant height, width and no. of leaves on 50th day when compared with outdoor plants at
15,000 lux light intensity. Thus from the above results, it can be concluded that the pollutantspresent in untreated tannery effluent can be reduced after combined treatment of
cyanobacteria, coir pith and the microbial consortia (from NRK) and the biomass obtained fromcombined treatment can be used as a organic manure for plant growth.
Acknowledgement
The authors are grateful to Model Organic Farm (MOF), Bharathidasan University,
Tiruchirappalli, Tamilnadu for the facility and completion of this work.
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