Exploring the Flora of South Sulawesi, Forest Vegetation, and Karst Areas as Bundle Dyeing on Silk Fabrics

e development of dyeing frm natural substances for silk fabrics has been rapidly growing in recent years. is study aimed to explore the plant species prodsucing unique dyes and patterns on silk fabrics.e owers and leaves of some plant species found at the research sites were assayed for their color and shape expression on the fabrics. e dyeing technique applied was the bundle dyeing or ecoprinting technique on the fabric’s surface with mordant alum and myrobalan. We obtained 297 plants consisting of 95 families and 181 genera. e plant species producing colors were trees (48.4%), shrubs (30.5%), and herbs, vines, ferns, and lycopods (21.1%). e plant species samples obtained were 213 (71.7%) producing color and 84 (28.3%) species not expressing color. e leaves and owers producing colors and patterns on the fabrics suitable for bundle dyeing were 126 species and 19 species, respectively. e leaves produce colors without shape patterns; thus, they have potential roles as dyes for the dipping technique.


Introduction
Natural dyes for fabrics are dyeing substances extracted from natural resources, such as plants, animals, and minerals. Most natural dyes are vegetable dyes from plants' parts, that is, roots, rinds, seeds, bark, owers, and wood, as well as other organic resources, such as fungi, lichens [1], and Serratia marcescens SB08 bacterium [2]. Even with organic waste, living organisms, and by-products from food, beverage, wood, agricultural, and other industries can be utilized as natural dyes [3]. ese natural dyes then go through several processes, namely, boiling, burning, bruising, pounding, or being directly used. e communities in developed countries and their textile industries have widely acknowledged the utilization of natural dyes for fabrics. Examples of plants for natural dyes are Indigofera or Isatis tinctoria in North Europe and England. Red colors on the textile are from madder (Rubia tinctorum), Manjistha or Indian madder (Rubia cordifolia), Brazilwood (Caesalpinia echinata), Sappan wood (Caesalpinia sappan), and Indian mulberry (Morinda citrifolia) [4]. Natural dyes can be easily obtained locally from several plant parts, such as leaves, bark, wood, or roots, so the cost is very cheap with several advantages [5]. Likewise, Indonesian tribes have been using natural materials for years as yarn dyes for woven fabrics.
e Iban Dayak tribe in Kapuas Hulu Regency, Kalimantan, uses plants as natural dyes: M. citrifolia L., Pandanus amaryllifolius, Curcuma domestica, Morinda tinctoria, and Psychtoria sp. [6]. In Sintang and Sambas Regencies, West Kalimantan, the traditional cloth weavers generate natural dyes from 36 plant species [7]. Additionally, some tribes in Indonesia have used these substances for dyeing the weave and batik fabrics that they become local wisdom. However, they have only applied dipping techniques for yarn and nished fabrics.
Fabric dyeing using natural dyes has undergone some developments, including direct contact dyeing techniques, better known as bundle dyeing or contact dyeing or ecoprint techniques. It is a simple technique by applying the plant part directly to the pretreated fabric. Contact dyeing is a creative method widely exerted by graphic art designers, textile designers, and artists [3].
is technique can be performed on fabrics; natural fibers: cotton, canvas, linen, and silk [3,8], and synthetic fibers: viscose, tencel, and polyester [3]. It also can be combined with the batik dyeing technique using plant leaves [9]. e silk dyeing raises the exclusive value of the artwork, and eventually, the purchase price will be very high. e prices of plain silk fabric range from IDR 60,000.00 to 115,000.00 (the equivalent of 4.24-8.13 USD in 2019) per meter, depending on the silk fibers. Nevertheless, after dyeing and patterning the bundle dyeing technique, the price will reach IDR 1,500,000.00 for 2.5 meters per piece of silk fabric [10]. us, it might be a profitable business opportunity.
Natural dyeing with bundle dyeing has become very popular because of its unique aesthetic value and limited product. e plant species are still limited to those that can express colors well. e most commonly used plant species in the ecoprint technique are ginkgo leaves, eucalyptus, willow, teak, and so on. e finding will inform new dyes of bundle dyeing or ecoprint for the practitioners. Samples were collected using the exploration method: exploring the entire forests and karsts areas and selecting representative plant species. e samples were trees, shrubs, bushes, vines, ferns, and herbs that had grown and/or were saplings. e selected leaves are shoots and mature leaves but before turning yellow. Flower samples were found according to flowering time. e collected plants were recorded with their scientific names, and the identification was performed for unknown species. e selected parts of the plant were from the shoot up to the 7 th -10 th leaves and flowers (if available). All plant parts were taken if it is the herb, sapling, or bush. e samples were immediately assayed before they were wilt. Samples assayed at the previous site were not reassayed at the following site but were recorded.

Preparation of Silk Fabric and Mordanting.
e silk fabric used was 150 × 200 cm. e fabric was soaked for 30 minutes in a 14 g/l TRO (Turkish Red Oil) solution. e fabric was rubbed, rinsed, and then squeezed. e fabric was drained until the water was no longer dripping, and then it was ready to be mordanted. e mordant solution consisted of 17 g/l alum (KAl (SO 4 ) 2 ·12H 2 O), 7 g/l myrobalan tannins, and 3 ml/l vinegar. e silk fabric was soaked in the mordant solution for 30 minutes. After that, the fabric was wrung out and drained until there was no more dripping solution.

Sample Arrangement on Silk Fabric.
e approach method used is to directly print the patterns using the shapes of plants on fabrics [11]. A damp fabric that has been mordant spread out on a flat surface. Samples of leaves/ flowers were arranged on the fabric and sorted according to the code. Each sample species was tested for mature shoots and leaves. e position of the leaf stomata was placed facing the fabric and vice versa. Samples that have been arranged were covered with plastic and then rolled and tied. Samples were steamed for two hours.

Data Collection.
Each plant sample was observed to express the color of the leaves or flowers on the fabric. e resulting colors were grouped without distinguishing the strength of the color. e leaf/flower motif depicted was described as "formed" or "unformed" on the silk fabric. Leaf samples consist of shoots and mature leaves but are not yet yellowed. e leaf sample is placed on fabric with the stomata facing down and vice versa e leaf sample is placed on fabric with the stomata facing down and vice versa.

Plant Species at Produce
Color. Samples collected from the educational forest of Hasanuddin University (site II) had more plants (97 plants) than other sites. is site has an area of 1,300 ha comprising natural forest with original vegetation. Kara and Lhotka [12] stated that unmanaged forests or natural forests possess higher biodiversity levels than managed forests, such as planted forests. As many as 53 species were found at site I in Hasanuddin University and its surroundings. At site III, the samples found were 92 species. Site IV-VI are karst areas with vegetation of no more than 60 species at each site. Most of the species at site VII were already found at the other sites. e samples obtained were 297 species consisting of 213 (71.7%) producing color and 84 (28.3%) species not expressing color.
ere are 95 families, 181 genera, 213 species of colored leaves, and 29 species of 16 families of colored flowers (Table 1). Exploration by Prigioniero et al. [13] in Southern Italy, Mediterranean Basin, identified 64.31% of plant species producing colors that were 25.2% of leaves and 18.5% of flowers. e expressed colors were divided into groups based on the percentage producing yellow, green, brown, orange, grey, red, black, faded blue, and pink (Figure 2(a)), and the life-forms were trees, bushes, herbs, vines, ferns, and lycopods that produce colors from their leaves (Figure 2(b)). e leaves and flowers that produced colors and patterns on the fabrics were 126 (59, 15%) species and 19 species, respectively. Eighty-four species that do not produce color in leaves and flowers are the families Poaceae, Arecaceae, Pinaceae, and Arecaceae. e families with leaves that expressed the greenest color and formed patterns were Euphorbiaceae, Fabaceae, and Malvaceae. e other seven families only had one species whose leaves produced green color. Genus of Malvaceae expressed green only in its shoots (genus Senna). e leaves of families Fabaceae, Myrtaceae, Lamiaceae, Bignoniaceae, Vitaceae, Asteraceae, and Meliaceae produced yellow color and patterns.
ree species from the families Fabaceae, Euphorbiaceae, and Lamiaceae expressed brown rust color. Syzygium guajava, Canarium decumanum, Aganosma marginata, Amorphophallus paeoniifolius, Spigelia, anthelmia, and Oroxylum indicum were the species from di erent families that produced orange color and patterns on the fabric of their leaves. Two species from the family Rubiaceae, Co ea spp., and Nauclea orientalis were also generated orange color, but the motif unformed on the fabric. us, those species are potential as dipping dyes. Family Rubiaceae generates reddish to dark orange dyes in the dipping technique [16]. Moreover, the owers generally used in dyeing are Cosmos sp. for orange dye [20] and Tagetes erecta for light brown [21]. e well-printed samples but unformed leaves or owers according to the sample, such as the owers of Hibiscus rosa sinensis L. and leaves of N. orientalis L. (Figures 3(h) and 3(i)). Bundle dyeing is a natural technique that transfers colors and shapes to produce patterns from natural substances, such as leaves or owers, to the fabric. Transferring colors and shapes to the fabric works well if it can display the original color and texture of the natural substance's surface in detail. e natural substances used must have sensitive pigments that can be expressed with the help of speci c triggers. e trigger in the fabric dyeing is called the mordant.Özen et al. [22] explained that the mordants that can be applied are potassium aluminum sulfate (alum), iron (II) sulfate, copper (II) sulfate, and tin chloride. In this research, we utilized alum and added myrobalan tannin to strengthen the color expression of the tested samples. Myrobalan is a plant species containing high tannin content, so it is used as a natural mordant [5]. Myrobalan will increase the a nity International Journal of Forestry Research   [23]. e application of alum mordant and natural myrobalan mordant is still relatively safe or nontoxic [24]. e color of each plant on the fabric may differ from the original color due to the used mordant types. e option of using alum as the mordant produces a color that is stronger and closer to the color without the mordant, as in G. dulcis produces a beige shade if without mordant and becomes a yellow shade using alum [17]. e iron (II) sulfate as mordant generates the natural color becoming darker (dark brown, grey, or even black) [17,[25][26][27]. It is the main reason for alum mordant and tannin application as preliminary research on natural substance dyeing.

e Color Expression on the
ere is no visual indication of plant species that can be used as a fabric dye base. Morphologically, there are no definite indications that the leaves can be used as fabric dyes. Leaf shape, rough or smooth leaf surface, many or few trichomes, and producing a sharp odor are not good indicators of color production. No characteristic of the lifeform groups (trees, shrubs, vines, or herbs) can be used as dyes. Likewise, under the position of the leaves on the surface of the fabric, two species of upper surface leaves produce color (A. leptopus and G. arboreum), and twentyfour species produce color in shoots. e printed color variations are highly dependent on the color pigments contained in the dyes used. e phytochemicals responsible for the dyeing are from the flavonoid group [20,28,29]. Organic dyes are divided into chemical classes: anthraquinone-to none, indigoid, naphthoquinone, carotenoids, flavones, dihydropyran, anthocyanidin, and flavonol [16]. e colors produced by teaks' (Tectona grandis) leaves are orange, red, bloody red, and dark brown with very strong and bright venation due to β-carotene pigment, pheophytin, pelargonidin 3-glucoside, pelargonidin 3,7-diglucoside, and anthocyanin [30]. At the same time, the green color is expressed from leaves rich in chlorophyll and other colors from indigotin [13].
e strength of the sample colors on the fabrics also depends on the presence of hydroxyl or carbonyl groups in the structure of the color pigment, which can be bound by the positively charged metal complex of the mordant. e dyes' metal anions and cations have a strong affinity for positively charged amino groups on the negatively charged carboxyl groups of silk fiber. us, ionic bonds are formed between the dye with the mordant and fiber, between metal and fiber, and eventually between the dye and metal ions. A dye molecule can only form a fabric fiber bond, while a mordant molecules bond with two or more plant color pigment molecules [25]. In addition to the pigment bonding to the mordant, the mordants' type and concentration also determine the color strength [31] and are not determined by the temperature at the time of dying [32]. e natural dyeing of the fabric depends on not only the mordant used but also the dyeing technique [33]. e highly vivid, sharp, and impressive visual effects are produced using a minimum amount of mordant plants for optimal application to obtain unique and nonrepeatable results [22]. e contact dyeing technique tends to produce random patterns or high concentrations of color in particular areas. ese unique colors and/or patterns cannot be duplicated, resulting in highly creative products. Preparation of substances is from various plants for dyes and patterns. e dyes' substances and textile types produce a variation in color strength in the contact dying technique [34]. Plant parts expressing strong color and providing detailed visualization of leaf venation are the best material for the bundle dyeing technique. e genus Leea, G. arboreum, A. leptopus, and O. indicum produce strong colors from yellow to orange groups. Young teak (T. grandis) leaves have the most robust red color and clear venation in the red group.
e dye leaves with a clear venation pattern can also be used as dyes for the dipping technique. Natural dyeing with the dipping technique can be implemented as a basic dye on fabrics as a combination before bundle dyeing. Fresh or dried coffee leaves can be a suitable fabric dye by extracting dyeing solution [35]. Eighty-seven species that produced colors but were unformed can produce color by dipping technique, for example, H. rosa sinensiss' flowers and N. orientaliss' leaves. As the Bidayuh Dayak Tribe, Sanggau, West Kalimantan, uses the ground flower of H. rosa sinensis (Malvaceae) and produces green color with the addition of calx [15]. Meanwhile, H. sabdariffa contains anthocyanin pigment, an important dye-producing plant [36]. Anthocyanins give red, purple, and blue colors produced by flowers or fruits [37].

Conclusion
is study expects to find alternative dyes for silk fabrics to meet the consumer demand for environmentally friendly products increasing lately. Exploration of the color-producing plant species that are found around us has not been revealed yet. Several species of plants can be an alternative to dye silk cloth, especially the leaves.
ere are 126 species of plants that can be used as dyes using the bundle dyeing technique and 87 species that produce colors without patterns formed but have the potential as dyes for yarn or fabric. e colors investigated in this study can still be described differently by trying other types of mordant.
Data Availability e vegetation-enumerated data used to support the findings of this study are included within the article. Disclosure e funding agency did not influence the design of the study; the collection, analyses, or interpretation of data; and the writing of the manuscript.

Conflicts of Interest
e authors declare no conflicts of interest.