**2. Plants with antifungal activity**

The mankind has been using plants as medicine to treat different kinds of diseases, including fungal infection. *Acorus calamus* (sweet flag), one of the medicinal plants, has antifungal activity, and the compound responsible for this activity is α-asarone that was tested on *Fusarium oxysporum* [3, 4]. *Ageratum conyzoides* that belongs to the family Asteraceae is traditionally used to treat fresh cut. It accelerates the recovery of the tissue and prevents infection. The leaves are hairy consisting ordinary trichome and glandular hair containing volatile oil. The extract of *Ageratum* leaf contains antifungal compound that is active toward *Aspergillus niger*, *Pestalotiopsis theae*, *Rhizoctonia solani*, and *Candida albicans* [5, 6]. The responsible compounds for the antifungal activity are volatile oil components and chromene compound that was further identified as coumarin [6, 7]. Garlic (*Allium sativum*) is commonly used as spices and herbal medicine and used as antibacteria, antifungi, antivirus, antihyperlipidemia, antiplatelet aggregation, and blood fibrinolytic agent [8]. The extract of garlic is active toward *Fusarium oxysporum*, *Phytophthora capsici*, *Aspergillus niger*, *Aspergillus flavus*, *Trichophyton rubrum*, and *Trichoderma harzianum* [9–12]. The compound that is responsible for the antifungal activity is allicin and ajoene.

fruits produced by the plant. The mankind, however, has used secondary metabolite produced by plants since the ancient time. People use plant secondary metabolites as medicine,

66 Fusarium - Plant Diseases, Pathogen Diversity, Genetic Diversity, Resistance and Molecular Markers

Plants have been traditionally used as fungicide for various purposes such as food preservatives and treatment of skin diseases. Tofu that is made from soya curd is rinsed with yellow pigment of turmeric to make the color of tofu into yellow and to extend the shelf life of tofu. Garlic is traditionally used together with cassava starch to catch spore of yeast needed for fermentation of soya bean to make *tempeh* (fermented soya bean) and *tape* (fermented cassava). The addition of garlic is intended to inhibit the growth of microorganism, but the spore can still survive and can grow under suitable environment, when it is mixed with the appropriate substrates such as cassava, rice, soya bean, and other carbohydrate-containing materials to produce fermented products. *Alpinia galanga* rhizome is sliced, and the rough surface is rubbed on the skin infected by *Trichophyton*. *Cassia alata* leaves are boiled and used for bathing to treat itchy and ringworm caused by fungal infection. *Piper betel* leaves are boiled and used for washing vaginal area to treat and to prevent candidiasis. *Ageratum conyzoides* leaves is rolled up and patched on a new cut to protect the tissue from infection by microorganisms

Many secondary metabolites from plants have been extracted, fractionated, isolated, and studied for the antifungal activity. Volatile oil is the secondary metabolites that play many important roles in human daily life, such as perfumery, spices, essence, medicine, aromatherapy, insect repellent, and also as fungicide [1]. Many medicinal plants contain volatile oil; many of them have been traditionally used in cut healing or as natural preservatives due to their capacity to control the growth of bacteria and or fungi [2]. Coumarin is reported to be one of the antifungal compounds present in the leaves of *Ageratum conyzoides* in addition to the volatile oil components. So far not much information on the traditional use of plants as antifungi for plants infected by fungi including soil-borne pathogenic fungi such as *Fusarium* and *Phytophthora*. Plants infected by soil-borne fungi are extremely hard to eradicate. In some cases, burning of the remaining plant is the only way to eradicate the pest accompanied by replacement with different crops. The possibility of plant secondary metabolites to be developed as source for natural fungicide especially for antifusarium and antiphytophthora is explored and discussed and supported with published reports and

The mankind has been using plants as medicine to treat different kinds of diseases, including fungal infection. *Acorus calamus* (sweet flag), one of the medicinal plants, has antifungal activity, and the compound responsible for this activity is α-asarone that was tested on *Fusarium oxysporum* [3, 4]. *Ageratum conyzoides* that belongs to the family Asteraceae is traditionally used to treat fresh cut. It accelerates the recovery of the tissue and prevents infection. The leaves are hairy consisting ordinary trichome and glandular hair containing volatile oil. The

spices, perfumery, poison, pest control, etc.

and accelerate wound healing.

experimental data.

**2. Plants with antifungal activity**

*Alpinia galanga* is one of the medicinal plants that belongs to family Zingiberaceae and also used as seasoning. Zingiberaceae is a plant family by which the member of the family is widely used as spices and herbal medicines. The organ used is mostly the subterranean part of the plant known as rhizome. When the rhizome of *A. galanga* is sliced transversally, it produces a rough surface and traditionally used by rubbing on the skin infected by fungi, such as ringworm. The extract of the rhizome is active against *Fusarium oxysporum*, and one of the active compounds is acetoxychavicol [13]. *Curcuma domestica* known as turmeric is popular as the main spice in making curry, a popular cuisine in India and South East Asia. Turmeric extract is active toward *Phytophthora infestans*, *Exserohilum turicicum*, *Fusarium oxysporum*, and *Colletotrichum cassiicola* [14–16]. The active compounds are the component of volatile oil, i.e., eucalyptol, β-pinene, and camphor. Differed from *Curcuma domestica*, *Curcuma xanthorrhiza*, known as Java turmeric due to its bitter taste is mainly for herbal medicine. Java turmeric extract is active against *Candida albicans*, *Candida glabrata*, *Candida guilliermondii*, *Candida krusei*, *Candida parapsilosisi*, and *Candida tropicalis*, and the active compound is xanthorrhizol [17].

*Curcuma zedoaria* is also widely used as herbal medicine and even claimed as anticancer. The extract obtained from the rhizome of *C. zedoaria* has antifungal activity toward *Trichophyton rubrum*, *Aspergillus niger*, *Saccharomyces cerevisiae*, *Epidermophyton floccosum*, *Aspergillus fumigates*, *Penicillium purpurogenum*, *Trigonopsis variabilis*, *Microsporum gypseum*, *Sclerotium rolfsii*, *Geotricullar candiade*, *Fusarium oxysporum*, *Helminthosporium oryzae*, *Candida krusei*, and *Trichophyton mentagrophytes*, and the active compound is ethyl-p-hydroxycinnamate [18]. Ginger (*Zingiber officinale*) is mainly used as spices and also as herbal medicine. The rhizome contains volatile oil and pungent compounds gingerol and shogaol that are well recognized as antiemetic agent. Ginger extract is active toward *Aspergillus flavus*, *Aspergillus niger*, *Penicillium griseofulvum*, *Fusarium oxysporum*, and *Pyricularia oryzae* [5, 19] with zingerone as the active compound. Zingerone is one of the ginger oil components that belongs to the group of phenylpropanoid compounds.

*Cassia alata* is a shrub that belongs to the Caesalpiniaceae family. Traditionally, *C. alata* leaves are boiled and used by bathing to treat fungal infection causing skin diseases. The extract of the leaves is active toward *Trichophyton rubrum*, *Microsporum gypseum*, *Trichophyton mentagrophytes*, *Epidermophyton floccosum*, *Aspergillus niger*, *Phytophthora notatum*, and *Fusarium solani* [3, 20–22], and the active compound was identified to be anthraquinones. Cinnamomum leaves contain volatile oil that contains cinnamaldehyde and eugenol and are reported to be active toward *Candida albicans* [23–25]. *Cymbopogon nardus* leaves contain high quantity of volatile oil that is frequently used as insect repellent. The oil is also active as antifungal agent toward *Erysiphe cichoracearum*, *Aspergillus, Penicillium*, and *Erollium*, and the active antifungal compounds are citronellal and linalool [26]. *Eclipta alba* is commonly used as an ingredient in making hair tonic. The extract was reported to be active toward *Candida tropicalis* and *Candida albicans* [27]. *Garcinia mangostana* fruit is one of the most delicious tropical fruit. Garcinia fruit cortex that is rich in tannin and mangosteen is now commercially used as raw material for herbal medicine. Garcinia extract is active as antifungi toward *Candida albicans*, *Epidermophyton floccosum*, *Alternaria solani*, *Mucor* sp., *Rhizopus* sp., and *Cunninghamella echinulata* [28].

*Piper betel* leaf is traditionally chewed together with limestone and gambier by Melanesian to stain teeth and protect from infection. The leaf is also used to treat and to prevent vagina and mouth cavity from candidiasis. Betel leaf extract is reported to be active as antifungal agent for *Colletotrichum gloeosporioides*, *Botryodiplodia theobromae*, *Rhizoctonia solani*, *Aspergillus* sp., *Penicillium* sp., and *Fusarium* sp. Hydroxychavicol and eugenol were reported to be the responsible antifungal compounds [29]. *Piper crocatum* is locally named as red betel; it has more bitter taste than the ordinary betel. It is considered to be more potent as herbal medicine compared to the ordinary betel; however, the volatile oil content and the antimicrobial activity were lower. The extract of red betel is active toward *Candida albicans*, *Colletotrichum gloeosporioides*, and *Botryodiplodia theobromae* [30, 31]. *Syzygium aromaticum* flower bud and leaves contain volatile oil with eugenol as the major component. The oil content of the flower bud is much higher compared to the leaves and so the eugenol content [32]. The flower bud is usually used as seasoning in cigarette-making. It is also used as local anesthesia for dental illness. The extract of clove is an active antifungi and is also active toward *Fusarium oxysporum* [4, 33, 34]. Eugenol is one of the clove oil components that has antifungal activity [35, 36].

material. The individual active compound may be very active but present only at low concentration; consequently, the activity becomes low when the sample concentration is calculated based on the plant material. The flower bud of *Syzygium polyanthum* contains approximately 15% with eugenol content that can reach 80%. Coumarin in *Ageratum conyzoides* on the other hand only presents at very low concentration. However, for the application purpose, clove is considered potential to be used as source of antiphytophthora from plants. The rhizome of *C. xanthorrhiza*, *C. zedoaria*, *C. domestica*, and *Cassia alata* leaves can be used as alternatives. The

Note: Extract was made by maceration in methanol: +: 1–25% inhibition; ++: 26–50% inhibition; +++: 51–75% inhibition;

**No. Plant Plant organ Concentration**

 *Ageratum conyzoides* Linn. Aerial part + ++ *Cassia alata* L. Leaves + +++ *Piper betel* L. Leaves ++ ++ *Allium sativum* L. Bulb ++ ++ *Alpinia galanga* L. Rhizome ++ ++ *Curcuma domestica* Val. Rhizome ++ +++ *Curcuma xanthorrhiza* Roxb. Rhizome +++ +++ *Curcuma zedoaria* (Berg.) Roscoe. Rhizome +++ +++ *Zingiber officinale* Rosc. Rhizome ++ ++ *Cymbopogon nardus* L. Leaves ++ ++ *Syzygium aromaticum* L. Flower bud ++++ ++++

**0.5% 1.0%**

69

http://dx.doi.org/10.5772/intechopen.71552

Plant Secondary Metabolites for Antifusarium and Antiphytophthora

Compared to *P. palmivora*, *F. oxysporum* is less susceptible toward the extract of antifungal plant. Higher concentration of plant extract is needed to observe the growth inhibition of the *F. oxysporum* culture by the extract. On *P. palmivora*, culture growth inhibition can be observed at extract concentration lower than 0.5%, whereas on culture of *F. oxysporum*, the inhibition can be observed at higher than 1%. Seven of 17 plants reported or traditionally used as antifungal agents inhibit the growth of *F. oxysporum* (**Table 2**). High inhibition activity is demonstrated by clove bud extract, and relatively high activity is shown by clove leaf extract. Inhibition by the extract of *Piper betel*, *Curcuma domestica*, *Curcuma xanthorrhiza*, *Zingiber offici-*

**Tables 1** and **2** show that clove bud and clove leaves are potential source of secondary metabolite for antifusarium and antiphytophthora. Clove bud contains 15–20% volatile oil with major components consisting eugenol (80–90%), eugenol acetate (10–15%), and caryophyllene (3%). Clove leaves also contain volatile oil, but the composition is different, and the content is much lower

price of the plant materials are much cheaper compared to clove bud.

*nale*, and *Acorus calamus* can be considered to be low [31].

**Table 1.** Activity of 11 antifungal plants on *Phytophthora palmivora*.

++++: 76–100% inhibition.

The antifungal plants described above were extracted using methanol, and the extract obtained were tested toward *Fusarium oxysporum* and/or *Phytophthora palmivora*. The relative activities were compared, and the results are described in Section 3.
