Livestock Research for Rural Development 34 (10) 2022 LRRD Search LRRD Misssion Guide for preparation of papers LRRD Newsletter

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Amino acid and fatty acid compositions of black soldier fly larvae (Hermetia illucens) fed by Tofu by-products in Viet Nam

Pham Thi Phuong Lan, Nguyen Hai Quan, Le Duc Ngoan, Tran Thi Thu Hong and Nguyen Duy Quynh Tram

University of Agriculture and Forestry, Hue University, Viet Nam
ndqtram@hueuni.edu.vn

Abstract

The study was carried out to determine the amino acid and fatty acid compositions of black soldier fly larvae (Hertemia illucens) fed by tofu by-products (TF). This was a completely randomised design with 2 treatments and 4 replicates. The larvae were fed by TF and collected at 2 times as 2 treatments according to the change of colour as dark yellow (7 days after rearing or 12 day old larvae, namely 7D) and black yellow (9 days after rearing or 14 days old larvae, namely 9D) for amino acid and fatty acid analyses. Results show that two essential amino acids histidine and valine were higher in 7D than in 9D (P<0.05) and crude fat contains low lauric acid and high linoleic acid (w-6) and α-linolenic acids (w-3). It is concluded that proteins in the larvae were rich in lysine and methionine as in fishmeal but poor in histidine and leucine. Ether extract of the larvae contains low lauric acid and high linoleic acid and α-linolenic acid. Beside protein, it seems that larvae can be used as good source of essential fatty acid. In recommendation, black soldier fly larvae fed by tofu by-product could be collected at 7-9 days after rearing at temperature 30-35°C for supplying sources of protein and essential fatty acids.

Keywords: larvae development, linoleic acid and α-linolenic acid, lauric acid


Introduction

The black soldier fly (Hermetia illucens) has been studied in recent years as a source of animal and aquaculture feed, replacing protein-rich feed sources such as fishmeal and soybean meal (Barragan-Fonseca et al 2017; Cullere et al 2017; Spanghers et al 2017; Moula et al 2018). Black soldier fly is native to the Americas but is now widely reared around the World due to its ability to adapt to high temperature ranges (10-42oC), but at 30oC, it has a high growth potential (Lalander et al 2019). Black soldier fly larvae (BSFL) has a high nutritional content such as dry matter (DM) (35-45%), crude protein (37-63% as DM), crude fat (7-39%), crude fibre (7.0%), ash (14.6-28.4%) and 5278.49 kcal gross energy per kg DM (Barragan-Fonseca et al 2017; Sheppard et al 2008; Arango Gutierrez et al 2004; St-Hilaire et al 2007). Besides, Arango Gutierrez et al (2004) reported that larvae are rich in macro-minerals such as calcium (5-8% DM) and phosphorus (0.6-1.5% DM), and micro-minerals such as potassium (0.69% DM), sodium ( 0.13% DM), magnesium (Mg; 0.39% DM), iron (Fe; 0.14% DM), manganese (Mn; 246 mg/kg DM), zinc (Zn; 108 mg/kg DM) and copper (Cu; 6.0 mg/kg DM).

Cullere et al (2016) reported that the most abundant essential amino acid (EAA) were valine and leucine, whereas alanine and glutamic acid were rich in defatted BSF larvae meal. The AAs concentration of defatted BSF larvae meal differed from the full-fat BSF larvae meal presented by De Marco et al (2015): regarding EAAs, lysine, methionine, arginine and histidine contents were lower in defatted BSF larvae meal compared with those of the above-mentioned study, whereas for isoleucine, leu, phenylalanine, threonine and valine the situation was reversed.

The fatty acid (FA) composition of the BSF larvae depends on the FA composition of the diet. The lipids of larvae fed on cow manure contained 21% of lauric acid, 16% of palmitic acid, 32% of oleic acid and 0.2% of omega-3 FA, while these proportions were respectively 43%, 11%, 12% and 3% for larvae fed 50% fish offal and 50% cow manure (Makkar et al 2014). Total lipid content also increased from 21% to 30% DM. Feeding BSF larvae by cow manure and 22% fish offal within 24 h of their pupation was sufficient for a substantial enrichment in polyunsaturated fatty acid (PUFA), especially in docosahexaenoic acid and eicosapentaenoic acid (St-Hilaire et al 2007).

In Viet Nam, Tofu by-product (TF) from tofu processing is main source of agro-industrial by-products. TF has a high content of crude protein (20-25%) and crude fat (9-12%), and high crude fibre (50-65%) (Nguyen et al 2020). Recently, the use of TF to feed BSFL has been implemented in practice in some areas in the South. Nguyen Thi Bich Hao et al (2017) reported that BSFL developed well in TF substrate compared with chicken manure or mixture of chicken manure and TF. However, recent publications on chemical composition and nutritive values of BSFL fed TF are still limited, particularly amino acid and fatty acid compositions. This study, therefore, aimed at determing chemical, amino acid and fatty acid compositions of BSFL fed by Tofu by-products.


Materials and methods

The experiment was conducted at the Research and Training Centre (RTC), Faculty of Animal Husbandry and Veterinary Medicine, University of Agriculture and Forestry (HUAF), Hue University from Feb. to May 2021.

Experimental design

The larvae of 5 days old were randomly arranged in a completely randomised design with 2 treatments and 4 replicates. The larvae were collected at 2 times as 2 treatments according to the change of colour as dark yellow and black yellow at day 7th (12 days old larvae, namely 7D) and 9 th (14 days old larvae, namely 9D) after larval rearing, respectively.

Feeding and management

The larvae of 5 days old were reared in a plastic containers with a density of 2 larvae/cm2 (2,000 larvae/each box) at temperature of 30-35 oC and fed tofu by-products. They were fed daily at 100 mg/larvae (based on DM), ensuring excess feed for larvae to have maximum intake. Feed was prepared in the form of air-dry, after weighing, it was mixed with water at the ratio of 10 g of air dry feed and 17 g of water, ensuring that the substrate reaches a moisture content of about 70% suitable for the development of larvae, and was given once a day at 8:00am.

Chemical analysis

Samples of larvae were collected at day 7th and 9th after rearing for chemical analysis: DM, EE, CP and CF following AOAC (1990) procedures at the Lab of the Faculty of Animal Husbandry and Veterinary Medicine, HUAF.

Amino acid compositions were analysed by Performic Acid Oxidation with Acid Hydrolysis–Sodium Metabisulfite Method (AOAC 994.12; 1997) at the Lab of Biotechnology of the National Institute of Animal Sciences, Ha Noi. Fatty acid compositions were analysed by Gas Chromatography of Fatty Acid Methyl Esters Method (ISO 2017) at the Lab of Upscience, Ha Noi.

Data analysis

Data were presented in the form of the mean (M), standard error of the mean (SEM). The data were statistically processed by analysis of variance (ANOVA) by General Linear Model in Minitab v. 16.2 (2010). The difference between the mean values ​​was determined by the Tukey method at a confidence level of 95%. Statistical model:

Yij = µ + Ti + eij

Where: µ is the average value; Ti is the effect of growth stage; eij is the experimental error.


Results

Amino acid profile

Samples of adult larvae and pre-pupae were collected at day 7th and day 9th after rearing for amino acid and fatty acid analyses (Photo. 1A, B).

Photo 1. A 12 days old larvae (A) and 14 days old larvae (B)

Results in Table 1 on amino acid composition of 7D and 9D show no statistical difference (P<0.05) except for alanine, histidine and valine. As DM percentage, amino acids: alanine, histidine and valine concentrations are higher in 7L than those in 9L, and other amino acids are the same. However, as CP percentage, only amino acid alanine content of the 7L is higher than that of 9L, and other amino acids are not different.

Table 1. Amino acid composition of full-fat larvae fed tofu by-products collected at day 7th and 9th after rearing (n=4)

Amino acids

% dry matter

Source
#

% crude protein

7D

9D

SEM

p

7D

9D

SEM

p

Alanine

2.42a

2.02b

0.059

0.009

2.33

4.13a

3.70b

0.105

0.045

Arginine

2.19

1.97

0.281

0.598

2.05

7.74

7.16

0.314

0.839

Aspartic acid

4.54

3.92

0.189

0.081

3.63

7.74

7.16

0.313

0.260

Cystine

0.56

0.66

0.059

0.290

-

0.95

1.21

0.107

0.163

Glycine

2.42

2.12

0.239

0.429

1.78

4.12

3.88

0.443

0.720

Glutamic acid

6.88

6.07

0.378

0.202

4.52

11.73

11.09

0.675

0.540

Histidine

0.98a

0.74b

0.055

0.038

3.16

1.67

1.35

0.102

0.094

Isoleucine

2.21

1.63

0.342

0.301

1.56

3.77

3.00

0.608

0.421

Leucine

3.53

3.10

0.312

0.382

2.71

6.02

5.67

0.557

0.681

Lysine

3.63

3.56

0.096

0.645

2.32

6.18

6.51

0.191

0.289

Methionine

2.08

2.03

0.161

0.812

2.24

3.56

3.71

0.278

0.721

Phenylalanine

1.74

1.59

0.122

0.428

1.86

2.97

2.91

0.212

0.837

Proline

3.11

2.42

0.342

0.225

2.19

5.31

4.43

0.609

0.361

Serine

2.21

1.72

0.184

0.133

1.60

3.77

3.14

0.321

0.240

Threonine

2.49

2.50

0.089

0.947

1.84

4.25

4.57

0.143

0.185

Valine

3.91a

3.22b

0.148

0.030

1.87

6.66

5.88

0.269

0.110

ab : means in the same row for each parameter with different superscripts are significantly different (p <0.05)
# Amino acid profile of 14 day old larvae fed commercial broiler chicken feed (Liu et al 2017)

Recently, not very much publications on amino acid composition of the BSFL are found. In this study, protein of BSFL contain 17 amino acids as previous reports of Rawski et al (2020) and Vedkamp and Bosch (2015). The authors reported that BSFL with full-fat contained 17 amino acids. In this study, however, amino acid tryptophan could not determined. Many authors indicated that BSFL proteins contained almost essential and non-essential amino acids, and the ratio of amino acids was also affected by the substrate.

In this study, the lysine and methionine contained in the 7D and 9D 3.56-3.63% and 2.03-2.08% as DM, respectively and 6.18-6.51 g/16 g N and 3.56-3.71 g/16 g N, respectively (Table 1). Vedkamp and Bosch (2015) reported also that lysine contents of larvae and pre-pupae were 6.5 and 5.7 g/16 g N, respectively, and methionine of 1.9 and 1.7 g/16 g N. Therefore, data in this study are relevant to above previous publications.

Table 2. Amino acid profile of black soldier fly larvae (BSFL) as comparison with fish meal (FM), soybean meal (SBM) and ideal protein (IP) (g/160 g N)

Amino acid

BSFL#

FM##

SBM##

IP###

Lysine

63.5

67.1

57.2

70

Methionine

36.4

24.7

13.8

18

Met + Cys

47.2

34.8

29.2

36

Threonine

41.1

36.9

37.4

45

Tryptophan

-

10.2

14.7

12

Isoleucine

33.9

34.9

41.0

40

Leucine

58.5

66.9

74.7

80

Valine

62.7

42.2

43.2

52

Histidine

15.1

24.1

26.3

25

Phenyalanine

29.4

27.5

43.6

40

Phe + Tyr

-

52.7

74.6

80

# Mean of larvae collected at day 7th and 9 th; ##: La Van Kinh et al 2019; ### Boisen 1997

Amino acid profile of BSFL, fishmeal and soybean meal are comparable (Table 2), particularly, two common limiting amino acids lysine and methionine. In this study, lysine and methionine concentrations in BSFL are 63.5 and 36.4 g/160 g N, respectively and are not limiting amino acids, however, concentrations of histidine and leucine are two. This results are relevant to previous reports that BSLF proteins are rich in two limiting amino acids, lysine and methionine (Rawski et al 2020). The authors indicated that lysine and methionine contents in BSFL were of 68.2 g/160 g N and 21.2 g/160 g N, respectively.

Fatty acid composition

Data in Table 3 show that Omega-6, Omega-9 fatty acid and PUSFA concentrations are higher in the larvae that those in pre-pupae as percentage of crude fat (P<0.05). However, Omega-3 and MUSFA concentrations as DM percentage are higher in the pre-pupae than in the larvae (P<0.05).

Table 3. Fatty acid profile of the larvae fed Tofu by-products collected at day 7th and 9th after rearing (n=4)

Fatty acids

% relative fat

g per 100 g dry matter

Sources# (%
as crude fat)

7D

9D

SEM

p

7D

9D

SEM

p

Capric acid

0.30

0.34

0.028

0.400

0.05b

0.07a

0.004

0.027

0.3-3.2

Lauric acid

12.95

15.39

1.131

0.202

2.28

3.31

0.346

0.103

19.2-58.5

Myristic acid

2.81

3.32

0.242

0.209

0.48

0.69

0.064

0.075

3.1-8.8

Palmitic acid

19.69

19.17

0.370

0.372

3.31b

3.92a

0.146

0.042

11.2-14.8

Palmitoleic acid

3.11b

3.47a

0.039

0.003

0.52b

0.71a

0.043

0.036

1.3-11.6

Stearic acid

4.36a

3.74b

0.091

0.009

0.72

0.76

0.032

0.472

1.4-3.6

Oleic acid

22.69a

20.68b

0.394

0.023

3.72

4.14

0.164

0.146

7.2-23.7

Linoleic acid

29.70

27.57

0.697

0.096

4.84

5.47

0.217

0.109

5.8-22.1

α-Linolenic acid

1.89

2.04

0.069

0.201

0.31b

0.40a

0.016

0.017

0.04-2.2

Arachidic acid

0.38a

0.266b

0.039

0.115

0.06

0.05

0.005

0.772

0.04-0.05

Eicosadienoic acid

0.26b

0.38a

0.039

0.110

0.04b

0.07a

0.003

0.001

-

Omega-3

1.67

1.80

0.047

0.116

0.31b

0.40a

0.016

0.017

-

Omega-6

26.13a

24.37b

0.310

0.016

4.84

5.49

0.222

0.105

-

Omega-9

20.67a

19.00b

0.388

0.039

3.84

4.31

0.165

0.119

-

SFA##

39.03

40.90

0.805

0.176

0.16

0.21

0.016

0.072

-

MUSFA##

31.27

30.83

0.585

0.628

5.82b

7,00a

0.265

0.031

-

PUSFA##

29.70a

28.27b

0.322

0.035

5.49

6.36

0.269

0.084

-

Total fatty acid

100

100

18.86b

22.90a

1.094

0.049

-

ab : means in the same row for each parameter with different superscripts are significantly different (p <0.05) # Li et al 2011; Nguyen et al 2017; Abduh et al 2020 ##SFA: Saturated fatty acids; MUSFA: monounsaturated fatty acids; PUSFA: Polyunsaturated fatty acids

Lauric acid has been shown to act as a prebiotic on the micro-biota of animals (Mohana Devi and Kim 2014) and as an antibiotic against gastrointestinal pathogens (Skrivanova et al 2006). In this study, lauric acid contents are not significant in the larvae and pre-pupae and range 12.95-15,39% as total fatty acid or 2.28-3.31% as DM, and these data are lower than previous publications. Rawski et al (2020) and Cullere et al (2017) reported that BSFL contained lauric acid of 21% and 23.4-49.3% as total fatty acid, respectively. Therefore, BSFL can be considered as an alternative to antibiotics which are increasingly banned for use in animal feed.

In addition, the concentrations of two essential fatty acids (linoleic and α-linolenic acid) in 7D and 9D in this study are not different (P>0.05) and are 27.57-29.7% and 1.89-2.04% as total fat, respectively. The data in this experiment are higher than previous publications (Rawski et al 2020; Sealey et al 2011; Cullere et al 2017). Rawski et al (2020) reported that BSFL contained linoleic acid of 3.8% and α-linolenic acid of 0.5% as crude fat. Sealey et al (2011) showed that two essential fatty acids were both presented in the fat of the larvae although in small concentrations (linoleic acid: 3.6-9.4% and α-linolenic: 0.1-0.8% of total fat). The authors concluded that the fatty acid content of the larvae depends on the substrate they feed on. In this study, Tofu by-products are used, or layer’s commercial feeds in other studies (Sealey et al 2011; Cullere et al 2017) or avocado or mixture of avocado and tofu by-product (Abduh et al 2020) were utilised, etc. Further, more studies on the effects of substrates feeding BSFL on their fatty acid profile are needed.


Conclusions

In recommendation, black soldier fly larvae fed by Tofu by-products can be harvested 7-9 days after rearing under environmental temperature of 30-35oC for protein and essential fatty acid feed sources.


Acknowledgements

The authors acknowledge the financial support of the Strong Research Group Program of Hue University (06/HĐ-ĐHH) and Scientific Research Program of Hue University (DHH2021-02-149).


Reference

Abduh M Y, Tejo F, Hidya G M S, Joseph R, Putra R E, Manurung R, Permmana A D and Mandasari M I 2020 Production of protein hydrolsyate and biodiesel from black soldier fly larvae cultivating using Rotten avacana and Tofu residue.London Journal of Research in Science:: Natural and Formal; 20(8): 25-38.

AOAC 1990 Official Methods of Analysis. 15th ed. Association of Official Analytical Chemists, Arlington, VA, USA: AOAC International.

AOAC 1997 Official Method 994.12 Amino Acids in Feeds.

Arango Gutiérrez G P, Vergara Ruiz R A and Mejía Vélez H 2004 Compositional, microbiological and protein digestibility analysis of the larva meal of Hermetia illuscens L. (diptera: Stratiomyiidae). at Angelópolis-Antioquia, Colombia, Revista Facultad Nacional de Agronomía, Medellín, 57, 2491-2500.

Barragan-Fonseca K B, Dicke M and van Loon J J A 2017 Nutritional value of the black soldier fly (Hermetia illucens L.) and its suitability as animal feed – a review. Journal of Insects as Food and Feed, 3(2): 105-120. doi 10.3920/JIFF2016.0055

Boisen S 1997 Ideal protein – and its suitability to characterize protein quality in pig feeds. A Review. Acta Agriculturae Scandinavica, Section A - Animal Science 47: 31-38. https://doi.org/10.1080/09064709709362367.

Cullere M, Tasoniero G, Giaccone V, Miotti-Scapin R, Claeys E, DeSmet S, Dalle Zotte A 2016 Black soldier fly as dietary protein source for broiler quails: apparent digestibility, excreta microbial load, feed choice, performance, carcass and meat traits. Animal,12(3):640-647, 1–8. DOI: 10.1017/S1751731117001860

Cullere M, Tasoniero G, Giaccone V, Acuti G, Marangon A and Dalle Zotte A 2017 Black soldier fly as dietary protein source for broiler quails: Meat proximate composition, fatty acid and amino acid profile, oxidative status and sensory traits. Animal, 10(12):1923-1930.doi: 10.1017/S1751731116001270.

De Marco M, Martínez S, Hernandez F, Madrid J, Gai F, Rotolo L, Belforti M, Bergero D, Katz H and Dabbou S 2015 Nutritional value of two insect larval meals (Tenebrio molitor and Hermetia illucens) for broiler chickens: apparent nutrient digestibility, apparent ileal amino acid digestibility and apparent metabolizable energy. Animal Feed Science Technology, 209:211–218, DOI: 10.1016/j.anifeedsci.2015.08.006

Mohana Devi S and Kim I H 2014 Effect of medium chain fatty acid (mcfa) and probiotic (Enterococus faecium) supplementation on the growth performance, digestibility and blood profiles in weaning pigs.Veterinari Medicina, 59:527-535.

ISO 2017 ISO 12966-2:2017: Animal and vegetable fats and oils-Gas Chromatography of fatty acid methyl esters.

Kinh L V, Ngoan L D and Quan N H 2019 Nutrition and feeding pigs. Vietnam Agriculture Publishing House. ISBN: 978-604-60-3050-8

Lalander C, Diener S, Zurbrugg C, Vinneras B 2019 Effects of feedstock on larval development and process efficiency in waste treatment with black soldier fly (Hermetia illucens). Journal of Cleaner Production 208: 211-219. https://doi.org/10.1016/j.jclepro.2018.10.017

Li Q, Zheng L, Cai H, Garza E, Yu Z and Zhou S 2011 From organic waste to biodiesel: Black soldier fly, Hermetica illucens, makes it feasible. Fuel 90: 1545-1548

Liu X, Chen X, Wang H, Yang Q, ur Rehamn K, Li W, Cai M, Li Q, Mazza L, Zhang J, Yu Z and Zheng L 2017 Dynamic changes of nutrient composition throughout the entire life cycle of black soldier fly. PLOS one from https://doi.org/10.1371/journal.pone.0182601

Makkar H, Tran G, Heuze V and Ankers P 2014 State-of-the-art on use of insects as animal feed, Animal Feed Science and Technology, 197 (0), 1-33.

Minitab 2010 Minitab Inc. US. Licensing 16.2.0.0

Moula N, Scippo M, Douny C, Degand G, Dawans E, Cabaraux J, Hornick J, Medigo RC, Leroy P, Francis F and Detilleux J 2018 Performances of local poultry breed fed black soldier fly larvae reared on horse manure. Animal Nutrition, 4, 73-78.DOI: 10.1016/j.aninu.2017.10.002

Nguyen H C, Liang S H, Doan TT, Su C H and Yang P C 2017 Lipase-catalysed synthesis of biodiesel from black soldier fly ( Hermetica illucens): Optimisation bu using response surface methodology. Energy Conversion and Management. 145: 335-342

Nguyen Thi Bich Hao, Pham Thi Thuy and Nguyen Hai Hoa 2017 Feeding black soldier fly (Hermeria illucens) by different substrates for the purpose of organically domestic solid-waste treatment Forestry Science and Technology Journal of Vietnam National University of Forestry,20/10 : 88-93.

Nguyen Q H, Than T T T, Le N D, Le P D and Fievez V 2020 Effect of increasing inclusion rates of tofu by-product in diets of growing pigs in nitrogent balance and ammonia emission from manure. Animal 14(6), 1176-1175.Doi :10.1017/S175173 1119003070.

Rawski M, Mazurkiewicz J, Kieronczyk B and Józefiak D 2020 Black soldier Fly full-fat larvae meal as an alternative to fish meal and fish oil in Siberian Sturgeon nutrition: The effects on physical properties of the feed, animal growth performance, and feed acceptance and utilization. Animals 2020, 10(11), 2119; doi:10.3390/ani10112119

Sealey W M, Gaylord T G, Barrows F T, Tomberlin J K, McGuire M A, Ross C and St-Hilaire S 2011 Sensory analysis of rainbow trout, Oncorhynchus mykiss, fed enriched black soldier fly prepupae, Hermetia illucens. Journal of the World Aquaculture Society, 42, 34–45.

Sheppard D C, Newton G L and Burtle G 2008 Black soldier fly prepupae: a compelling alternative to fish meal and fish oil.Public comment on alternative feeds for aquaculture, NOAA 15/11//2007 - 29/2/2008.

Skrivanova E, Marounek M, Benda V and Brezina P 2006 Susceptibility of Escherichia coli, Salmonella sp. And clostridium perfringens to organic acids and monolaurin. Veterinarni Medicina, 51 2006 (3), 81–88.

Spranghers T, Noyez A, Schildermans K and De Clercq P 2017 Cold hardiness of the black soldier fly (diptera: Stratiomyidae). J. Econ. Entomol., 110, 1501–1507.

St-Hilaire S, Sheppard C, Tomberlin J K, Irving S, Newton L, McGuire M A, Mosley E E, Hardy R W and Sealey W 2007 Fly prepupae as a feedstuff for rainbow trout (Oncorhynchus mykiss). Journal of the World Aquaculture Society, 38, 59–67.

Vedkamp T and Bosch G 2015 Insects: a protein-rich feed ingredient in pig and poultry diets. Animal Frontiers. 5(2): 45-50.https://doi.org/10.2527/af.2015-0019